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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(7): 968-975, 2023 Jul 06.
Artículo en Chino | MEDLINE | ID: mdl-37482733

RESUMEN

In recent years, the incidence of chest malignant tumors in China has increased year by year, which has seriously threatened the health problems of people. Among them, early screening and intervention of patients with chest malignancies is the key to cancer prevention. Early detection, early diagnosis, and early treatment as the "three early prevention" of clinical practice are conducive to improve the survival rate of tumor patients. As a non-invasive and real-time reflection of tumor status, liquid biopsy has gradually received attention in clinical diagnosis and treatment. Circulating tumor cells (CTCs), circulating tumor DNA (ctDNA) and exosomes as liquid biopsy "Three carriages" are not only widely used in the diagnosis, monitoring and prognostic evaluation of chest malignancies, but also face many unknown challenges. In this article, the application of liquid biopsy in chest malignancies in recent years is elaborated in detail, which provides a reference for the formulation of clinical tumor prevention and diagnosis and treatment strategies.


Asunto(s)
ADN Tumoral Circulante , Células Neoplásicas Circulantes , Humanos , ADN Tumoral Circulante/genética , Biopsia Líquida/métodos , Células Neoplásicas Circulantes/patología , China , Biomarcadores de Tumor
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(5): 685-690, 2021 May 06.
Artículo en Chino | MEDLINE | ID: mdl-34034412

RESUMEN

To explore the expression of p62 protein in lung adenocarcinoma (LUAD). In this study, a cross-sectional study was adopted. From December 2011 to May 2013, 60 patients with lung adenocarcinoma who were diagnosed and treated in Tongji Hospital of Tongji University, Shanghai were selected for paraffin embedding and tissue chip preparation, and immunohistochemistry (IHC) technology was used to detect the expression of p62 in lung adenocarcinoma patients' cancer tissues and adjacent tissues, and analyze the relationship between p62 expression and the clinicopathological characteristics and survival prognosis of patients with lung adenocarcinoma; at the same time, 6 cases of lung adenocarcinoma were selected by random sampling cancer tissues and adjacent tissues were detected by Western Blot (WB) to detect p62 protein and analyzed by gray value. Preoperative examination specimens of inpatients with lung adenocarcinoma diagnosed from April 2018 to early October 2019, and plasma specimens of healthy subjects were collected, and enzyme linked immunosorbent assay (ELISA) was used to detect lung adenocarcinoma patients and healthy patients. The expression of p62 in the plasma of the subjects was statistically analyzed using SPSS 22.0 software. The results of IHC showed that the positive expression rate of p62 in cancer tissues was significantly higher than that in adjacent tissues, and the difference was statistically significant (t=5.593, P<0.001). Similarly, WB results showed that the expression of p62 protein in cancer tissues was significantly higher than that in adjacent tissues. It is statistically relevant (t=2.238, P=0.049). The expression of p62 was statistically correlated with tumor size, clinicopathological stage and lymph node metastasis in patients with lung adenocarcinoma (all P<0.05). The overall survival of patients with lung adenocarcinoma with high p62 expression was worse than that of patients with low p62 expression (95%CI was 0.238-0.870, P=0.028), suggesting that the high expression of p62 is related to the poor prognosis of patients with lung adenocarcinoma. The level of p62 protein in the plasma of patients with lung adenocarcinoma was significantly higher than that in the healthy control group. The difference was statistically significant (t=8.533, P<0.001). The area under the receiver operating characteristic curve was 0.835 (95%CI was 0.779-0.891, P<0.001), which is significantly higher than CEA, CA125, CA153 and other single traditional indicators, and the combined detection of four indicators has the highest diagnostic efficiency. p62 was strongly expressed in cancer tissues and serum, which is related to the poor prognosis and overall survival rate of LUAD patients.


Asunto(s)
Adenocarcinoma del Pulmón , Adenocarcinoma , Neoplasias Pulmonares , Biomarcadores de Tumor , China , Estudios Transversales , Humanos
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 50(3): 553-559, 2018 Jun 18.
Artículo en Chino | MEDLINE | ID: mdl-29930429

RESUMEN

OBJECTIVE: To evaluate the effect of the vacuum-formed retainer on preventing the proximal contact loss between the implant supported crown and its adjacent natural teeth. METHODS: Forty-six posterior implant crowns in the mandible including 92 interproximal contacts in 46 patients (19 men, 27 women) aged from 25 to 66 years were included. The participants in experimental group (22 cases) were vacuum-formed retainers at night, while participants in control group (24 cases) only received routine examination. The two groups were not different in age, gender, the time interval of the tooth loss and tooth position at baseline. Mesial and distal proximal contact tightness was measured using the orthodontic dynamometer and metallic articulating film immediately after crown delivery, and 1-month, 3-month, 6-month, and 1-year follow-up respectively. The articulating film was inserted interdentally from the occlusal direction, and then it was slowly removed in the buccallingual direction by the dynamometer. Increasing the number of films (N) piece by piece until the frictional force (F) was great than 0, and the number of films (N) was recorded. At each follow-up, proximal contact between implant crown and its adjacent teeth was considered to be loss if the number of films (N) used at immediate crown delivery passed without frictional force (F=0). Besides, the periodontal conditions [scored according to the probing depth (PD), bleeding index (BI), mobility (M)] and complaint of food impaction were recorded. The mesial and distal proximal contact loss rates were compared between the two groups at different times. Chi-square test or Fisher's exact test was used for statistical analysis. RESULTS: The proximal contact loss rate on the mesial surface of the implant supported crown continuously increased over the follow-up periods. At the end of the 1-, 3-, and 6-month follow ups, 18.2%, 22.7% and 27.3% were identified for the contact loss rates on the mesial surface of the implant supported crown in the experimental group, respectively. Meanwhile in control group, the rates were 20.8%, 37.5% and 45.8%. No significant differences were observed at the end of the 1-, 3-, and 6-month follow ups(1-month: χ2=0.000, P=1.000; 3-month: χ2=1.183, P=0.277; 6-month: χ2=1.697, P=0.193). The proximal contact loss rate on the mesial surface in control group (62.5%) was significantly higher than that in the experimental group (31.8%, χ2=4.330, P=0.037) at the end of the 1-year follow-up. However, no statistical difference was found on the distal surfaces between the two groups during the whole follow-up periods. The first open contact was noted 1 month after crown insertion. CONCLUSION: By wearing vacuum-formed retainer for one year, the incidence of open contacts between the posterior implant prostheses and mesial adjacent teeth in the mandible has been reduced.


Asunto(s)
Coronas , Prótesis Dental de Soporte Implantado , Boca Edéntula , Implantes Dentales de Diente Único , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mandíbula , Enfermedades Periodontales , Diente , Pérdida de Diente , Vacio
4.
Insect Mol Biol ; 24(5): 551-60, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26174044

RESUMEN

The Spodoptera litura sterol carrier protein x (SlSCPx) gene is expressed in various tissues throughout the life cycle and plays important role in sterol absorption and transport. In this study, the effects of insect hormones (20-hydroexcdysone and juvenile hormone) and lipids (arachidonic acid, cholesterol) on the expression of SlSCPx was analysed by reverse-transcriptase PCR. The results showed that none of these substances significantly induced the expression of SlSCPx in Spodoptera litura-221 (Spli-221) cells. To identify the transcription factors responsible for regulation of SlSCPx expression, a 3311-bp promoter sequence of the gene was cloned. Transcriptional activity of the promoter was studied using an in vivo promoter/reporter system and a 29-bp sequence between -1000 and -1029 nucleotides (nt) upstream of this gene was found to be responsible for the up-regulation of the gene. Over-expression of CAAT/enhancer-binding protein (C/EBP) in Spli-221 cells increased the promoter activity 5.57-fold. An electrophoretic mobility shift assay showed that two nuclear proteins bound to this sequence. Recombinant C/EBP specifically bound with a putative cis-regulatory element (CRE). Mutation of the C/EBP CRE abolished the binding of the C/EBP with the CRE. These results suggest that the transcription factor C/EBP may regulate the expression of SlSCPx by binding to the CRE in the promoter of this gene.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas Portadoras/metabolismo , Spodoptera/metabolismo , Animales , Ácido Araquidónico/farmacología , Secuencia de Bases , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Portadoras/genética , Línea Celular , Colesterol/farmacología , Ecdisterona/farmacología , Metopreno/farmacología , Datos de Secuencia Molecular , Mutación , Regiones Promotoras Genéticas , Elementos Reguladores de la Transcripción , Spodoptera/efectos de los fármacos , Activación Transcripcional
5.
J Comp Pathol ; 150(2-3): 253-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24309906

RESUMEN

GM2 gangliosidosis (Tay-Sachs disease) was diagnosed in 6- to 8-month-old pedigree Jacob lambs from two unrelated flocks presenting clinically with progressive neurological dysfunction of 10 day's to 8 week's duration. Clinical signs included hindlimb ataxia and weakness, recumbency and proprioceptive defects. Histopathological examination of the nervous system identified extensive neuronal cytoplasmic accumulation of material that stained with periodic acid--Schiff and Luxol fast blue. Electron microscopy identified membranous cytoplasmic bodies within the nervous system. Serum biochemistry detected a marked decrease in hexosaminidase A activity in the one lamb tested, when compared with the concentration in age matched controls and genetic analysis identified a mutation in the sheep hexa allele G444R consistent with Tay-Sachs disease in Jacob sheep in North America. The identification of Tay-Sachs disease in British Jacob sheep supports previous evidence that the mutation in North American Jacob sheep originated from imported UK stock.


Asunto(s)
Gangliosidosis GM2/veterinaria , Enfermedades de las Ovejas/patología , Animales , Gangliosidosis GM2/genética , Gangliosidosis GM2/patología , Mutación , Ovinos , Enfermedades de las Ovejas/genética , Cadena alfa de beta-Hexosaminidasa/genética
6.
Biochemistry (Mosc) ; 78(7): 721-5, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24010835

RESUMEN

The lysosomal storage disorders (LSD) represent a heterogeneous group of inherited diseases characterized by the accumulation of non-metabolized macromolecules (by-products of cellular turnover) in different tissues and organs. LSDs primarily develop as a consequence of a deficiency in a lysosomal hydrolase or its co-factor. The majority of these enzymes are glycosidases and sulfatases, which in normal conditions participate in degradation of glycoconjugates: glycoproteins, glycosaminoproteoglycans, and glycolipids. Significant insights have been gained from studies of animal models, both in understanding mechanisms of disease and in establishing proof of therapeutic concept. These studies have led to the introduction of therapy for certain LSD subtypes, primarily by enzyme replacement or substrate reduction therapy. Animal models have been useful in elucidating molecular changes, particularly prior to onset of symptoms. On the other hand, it should be noted certain animal (mouse) models may have the underlying biochemical defect, but not show the course of disease observed in human patients. There is interest in examining therapeutic options in the larger spontaneous animal models that may more closely mimic the brain size and pathology of humans. This review will highlight lessons learned from studies of animal models of disease, drawing primarily from publications in 2011-2012.


Asunto(s)
Enfermedades por Almacenamiento Lisosomal/metabolismo , Aminopeptidasas/genética , Aminopeptidasas/metabolismo , Aminopeptidasas/uso terapéutico , Animales , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/genética , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/uso terapéutico , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Enfermedad del Almacenamiento de Glucógeno Tipo II/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo II/patología , Humanos , Enfermedades por Almacenamiento Lisosomal/tratamiento farmacológico , Enfermedades por Almacenamiento Lisosomal/patología , Enfermedad de Niemann-Pick Tipo C/tratamiento farmacológico , Enfermedad de Niemann-Pick Tipo C/metabolismo , Enfermedad de Niemann-Pick Tipo C/patología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapéutico , Serina Proteasas/genética , Serina Proteasas/metabolismo , Serina Proteasas/uso terapéutico , Tripeptidil Peptidasa 1 , alfa-Glucosidasas/genética , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/uso terapéutico
7.
Small ; 9(22): 3736-42, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-23606503

RESUMEN

A new class of targeted and immune-evading nanocarrier made using only biological components and facile processes is assembled in a bottom-up fashion. Simple top-down sequential addition of immune-evading or receptor-specific antibody elements conjugated to biosurfactant protein DAMP4 promotes self-assembly at an interface previously formed in the presence of peptide surfactant AM1, leading to a functional display at the interface through non-covalent molecular self-assembly.


Asunto(s)
Antígenos/metabolismo , Células Dendríticas/metabolismo , Emulsiones/química , Proteínas/metabolismo , Animales , Antígenos/química , Línea Celular , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Proteínas/química , Agua/química
8.
Vet Pathol ; 48(4): 807-13, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21123862

RESUMEN

The G(M2) gangliosidoses are a group of lysosomal storage diseases caused by defects in the genes coding for the enzyme hexosaminidase or the G(M2) activator protein. Four Jacob sheep from the same farm were examined over a 3-year period for a progressive neurologic disease. Two lambs were 6-month-old intact males and 2 were 8-month-old females. Clinical findings included ataxia in all 4 limbs, proprioceptive deficits, and cortical blindness. At necropsy, the nervous system appeared grossly normal. Histologically, most neurons within the brain, spinal cord, and peripheral ganglia were enlarged, and the cytoplasm was distended by foamy to granular material that stained positively with Luxol fast blue and Sudan black B stains. Other neuropathologic findings included widespread astrocytosis, microgliosis, and scattered spheroids. Electron microscopy revealed membranous cytoplasmic bodies within the cytoplasm of neurons. Biochemical and molecular genetic studies confirmed the diagnosis of G(M2) gangliosidosis. This form of G(M2) gangliosidosis in Jacob sheep is very similar to human Tay-Sachs disease and is potentially a useful animal model.


Asunto(s)
Gangliosidosis GM2/veterinaria , Enfermedades de las Ovejas/patología , Animales , Cerebelo/citología , Cerebelo/patología , Cerebro/patología , Femenino , Gangliosidosis GM2/genética , Gangliosidosis GM2/patología , Regulación de la Expresión Génica , Masculino , Ovinos , Enfermedades de las Ovejas/genética , Médula Espinal/patología
9.
Mol Genet Metab ; 95(1-2): 59-65, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18693054

RESUMEN

Tay-Sachs disease (TSD) is a progressive neurodegenerative disorder due to an autosomal recessively inherited deficiency of beta-hexosaminidase A (Hex A). Deficiency of Hex A in TSD is caused by a defect of the alpha-subunit resulting from mutations of the HEXA gene. To date, there is no effective treatment for TSD. Animal models of genetic diseases, similar to those known to exist in humans, are valuable and essential research tools for the study of potentially effective therapies. However, there is no ideal animal model of TSD available for use in therapeutic trials. In the present study, we report an animal model (American flamingo; Phoenicopterus ruber) of TSD with Hex A deficiency occurring spontaneously in nature, with accumulation of G(M2)-ganglioside, deficiency of Hex A enzymatic activity, and a homozygous P469L mutation in exon 12 of the hexa gene. In addition, we have isolated the full-length cDNA sequence of the flamingo, which consists of 1581 nucleotides encoding a protein of 527 amino acids. Its coding sequence indicates approximately 71% identity at the nucleotide level and about 72.5% identity at the amino acid level with the encoding region of the human HEXA gene. This animal model, with many of the same features as TSD in humans, could represent a valuable resource for investigating therapy of TSD.


Asunto(s)
Proteínas Aviares/metabolismo , Aves/metabolismo , Modelos Animales de Enfermedad , Hexosaminidasa A/metabolismo , Enfermedad de Tay-Sachs/enzimología , Animales , Proteínas Aviares/genética , Aves/genética , Encéfalo/enzimología , Encéfalo/metabolismo , Encéfalo/patología , Femenino , Expresión Génica , Hexosaminidasa A/genética , Humanos , Metabolismo de los Lípidos , Masculino , Mutación , Enfermedad de Tay-Sachs/genética , Enfermedad de Tay-Sachs/metabolismo , Enfermedad de Tay-Sachs/patología
10.
Mol Genet Metab ; 89(1-2): 156-63, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16854607

RESUMEN

Canavan disease (CD), an autosomal recessive neurodegenerative disorder, is caused by mutations in the aspartoacylase (ASPA) gene. In the present study, the ASPA gene was analyzed in 24 non-Jewish patients with CD from 23 unrelated families. Within this cohort, we found three large novel deletions of approximate 92, 56, and 12.13 kb in length, using both self-ligation of restriction endonuclease-digested DNA fragments with long-distance inverse PCR and multiplex dosage quantitative PCR analysis of genomic DNA. The 92 kb large deletion results in complete absence of the ASPA gene in one homozygous and one compound heterozygous patient, respectively. The 56 kb large deletion causes absence of the majority of the ASPA gene except for exon 1 alone in a compound heterozygous patient. The 12.13 kb deletion involves deletion of the ASPA gene from intron 3 to intron 5 including exons 4 and 5 (I3 to E4E5I5) in a compound heterozygous patient. Patients with the three large deletions clinically manifested severe symptoms at birth, including seizures. Our study showed that the combined use of long-distance inverse PCR and multiplex dosage quantitative PCR analysis of genomic DNA is a helpful and rapid technique to search for large deletions, particularly for detection of large deletions in compound heterozygous patients.


Asunto(s)
Amidohidrolasas/genética , Enfermedad de Canavan/diagnóstico , Pruebas Genéticas/métodos , Reacción en Cadena de la Polimerasa/métodos , Estudios de Casos y Controles , Estudios de Cohortes , Eliminación de Gen , Genoma Humano , Humanos , Análisis de Secuencia de ADN/métodos , Eliminación de Secuencia
11.
J Inherit Metab Dis ; 25(7): 557-70, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12638939

RESUMEN

Canavan disease, an inherited leukodystrophy, is caused by mutations in the aspartoacylase (ASPA) gene. It is most common among children of Ashkenazi Jewish descent but has been diagnosed in many diverse ethnic groups. Two mutations comprise the majority of mutant alleles in Jewish patients, while mutations in the ASPA gene among non-Jewish patients are different and more diverse. In the present study, the ASPA gene was analysed in 22 unrelated non-Jewish patients with Canavan disease, and 24 different mutations were found. Of these, 14 are novel, including five missense mutations (E24G, D68A, D249V, C152W, H244R), two nonsense mutations (Q184X, E214X), three deletions (923delT, 33del13, 244delA), one insertion mutation (698insC), two sequence variations in one allele ([10T>G; 11insG]), an elimination of the stop codon (941A>G, TAG-->TGG, X314W), and one splice acceptor site mutation (IVS1 - 2A>T). The E24G mutation resulted in substitution of an invariable amino acid residue (Glu) in the first esterase catalytic domain consensus sequence. The IVS1 - 2A>T mutation caused the retention of 40 nucleotides of intron 1 upstream of exon 2. The results of transient expression of the mutant ASPA cDNA containing these mutations in COS-7 cells and assays for ASPA activity of patient fibroblasts indicated that these mutations were responsible for the enzyme deficiency. In addition, patients with the novel D249V mutation manifested clinically at birth and died early. Also, patients with certain other novel mutations, including C152W, E214X, X314W, and frame shift mutations in both alleles, developed clinical manifestations at an earlier age than in classical Canavan disease.


Asunto(s)
Amidohidrolasas/genética , Enfermedad de Canavan/enzimología , Enfermedad de Canavan/genética , Mutación , Secuencia de Bases , Codón sin Sentido , Análisis Mutacional de ADN , ADN Complementario/genética , Exones , Genotipo , Humanos , Lactante , Recién Nacido , Judíos/genética , Mutación Missense , Fenotipo , Eliminación de Secuencia
12.
J Lipid Res ; 39(4): 845-60, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9555948

RESUMEN

Chylomicron remnants transport cholesterol from the intestine, and are removed from the circulation principally by the liver. While hepatic receptors, including the low density lipoprotein (LDL) receptor account for endocytosis, heparan sulfate proteoglycans (HSPG) participate in the initial binding of remnants to liver cells. To explore the interactions between HSPG and endocytosis of remnants, in the present study the expression of HSPG was inhibited in HepG2 cells transfected by a synthetic antisense oligodeoxynucleotide SYN5. Immunofluorescent staining by a monoclonal anti-syndecan antibody showed significant reduction in the expression of syndecan in SYN5-treated cells compared with control cells. Remnant binding decreased by about 50-70% in SYN5-transfected cells. Monoclonal antibodies to either heparan sulphate or the LDL receptor decreased binding by about 60-65%. The glycosylation inhibitor beta-nitrophenylxylopyranoside inhibited remnant uptake by 25%, whereas 4-nitrophenyl-beta-D-galactopyranoside had no effect on remnant binding. Heparinase completely abolished binding at appropriate concentrations. Heparitinase was less effective than hep arinase in inhibiting remnant binding. Suramin completely abolished the remnant binding. Poly-arginine, poly-lysine, and protamine all reduced remnant uptake by the cells, as did polybrene, a synthetic polycation, suggesting a role of cation-anion interactions in remnant binding. Brefeldin A, colchicine, and monensin caused the fluorescence associated with remnants to persist within the cells, confirming that blockers of tubulovesicular processes and Golgi function inhibit the intracellular transport and degradation of the remnants. Our results show that remnant binding to liver cells depends on the LDL receptor, on the expression of HSPG core proteins, and on the functionality of heparan sulfate in HSPG.


Asunto(s)
Quilomicrones/metabolismo , Endocitosis , Proteoglicanos de Heparán Sulfato/metabolismo , Hígado/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteoglicanos/metabolismo , Animales , Anticuerpos Monoclonales , Apolipoproteínas/análisis , Transporte Biológico/efectos de los fármacos , Colorantes Fluorescentes , Glicósidos/farmacología , Glicosilación/efectos de los fármacos , Proteoglicanos de Heparán Sulfato/genética , Liasa de Heparina/farmacología , Lípidos/análisis , Hígado/citología , Masculino , Glicoproteínas de Membrana/genética , Oligonucleótidos Antisentido , Polisacárido Liasas/farmacología , Proteoglicanos/genética , Ratas , Ratas Wistar , Receptores de LDL/inmunología , Receptores de LDL/metabolismo , Suramina/farmacología , Sindecanos
13.
Neuroendocrinology ; 66(3): 203-11, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9380278

RESUMEN

To explore the antitumor effect of insulin-like growth factor 1 (IGF-I) antisense RNA and the interaction of IGF-I with insulin-like growth factor-binding proteins (IGFBPs) in glioma cells, a recombinant retrovirus expressing IGF-I antisense RNA was constructed and introduced into C6 glioma cells. IGF-I antisense RNA reverses the transformed phenotype in glioma cells and inhibits glioma cell growth by blocking overexpression of endogenous IGF-I. Expression of IGFBP-2 is increased in glioma cells as compared with normal adult glial cells. IGF-I antisense RNA also inhibits expression of IGFBP-2 in glioma cells, but does not influence expression of the other IGFBPs. Although IGFBP-2 in conditioned medium from wild-type C6 cell cultures itself does not directly influence glioma cell growth, it synergistically enhances exogenous IGF-I-mediated DNA synthesis in IGF-I-negative C6 cells. These findings indicate the inhibitory effect of IGF-I antisense RNA on growth and development of glioma cells. IGF-I-dependent glioma cell growth may, in some circumstances, require IGFBP-2 as a cofactor. The antitumor effect of IGF-I antisense RNA is also associated with inhibition of IGFBP-2 expression.


Asunto(s)
Glioma/terapia , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/genética , ARN sin Sentido/uso terapéutico , Animales , División Celular/fisiología , Línea Celular Transformada , Supervivencia Celular , Medios de Cultivo Condicionados , ADN de Neoplasias/biosíntesis , Vectores Genéticos , Glioma/patología , Fenotipo , Ratas , Ratas Sprague-Dawley , Retroviridae/genética , Células Tumorales Cultivadas
14.
Clin Exp Pharmacol Physiol ; 24(3-4): 281-5, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9131298

RESUMEN

1. In vivo and in vitro gene-manipulated models were used to study the metabolism of chylomicron remnants. Transgenic mice expressing human apolipoprotein (Apo) A1 or E4, gene knockout mice deficient in ApoE or low density lipoprotein (LDL) receptors and antisense gene inhibition in HepG2 cells were used to evaluate the effect of gene manipulations on the metabolism of chylomicron remnants. 2. Mice transgenic for human ApoE4 showed accelerated clearance of chylomicron-like emulsions when animals were fed a low-fat diet. When challenged by a high-fat diet, remnant clearance in ApoE4 transgenic mice was delayed, as in normal or non-transgenic controls. However, unlike normal nontransgenic controls, in ApoE4 transgenic mice high density lipoprotein (HDL)-cholesterol levels remained high after high-fat feeding, which probably protected the animals from the development of atherosclerosis. In contrast, clearance of chylomicron-like lipid emulsions was not affected by the over-expression of human ApoAI in transgenic mice. 3. Gene knock-out mice deficient in ApoE or deficient in the LDL receptor were used to show that ApoE and LDL receptors are both essential for the normal, fast catabolism of chylomicron remnants by the liver. In the absence of the LDL receptor, an alternative ApoE-dependent pathway operates to clear chylomicrons from the plasma, with significantly delayed catabolism. 4. Antisense gene inhibition techniques were used to suppress the expression of syndecan, a core protein of heparan sulfate proteoglycan, in HepG2 cells. Remnant uptake in cells transfected with the antisense oligodeoxynucleotide complementary to a 20 nucleotide sequence upstream of the initiation site of syndecan cDNA markedly reduced the uptake of chylomicron remnant.


Asunto(s)
Quilomicrones/metabolismo , Animales , Apolipoproteína A-I/deficiencia , Apolipoproteína E4 , Apolipoproteínas E/deficiencia , Arteriosclerosis/etiología , Arteriosclerosis/metabolismo , Transporte Biológico/genética , Quilomicrones/sangre , Grasas de la Dieta/administración & dosificación , Humanos , Ratones , Ratones Noqueados , Ratones Transgénicos , Mutación , Oligonucleótidos Antisentido/genética , Receptores de LDL/deficiencia , Células Tumorales Cultivadas/metabolismo
15.
Res Vet Sci ; 61(3): 199-205, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8938847

RESUMEN

Two Carter type B Pasteurella multocida isolates, Izatnagar 52 and 25, isolated from cases of haemorrhagic septicaemia (HS), were used in a modified subtractive hybridisation technique with the specific aim of cloning unique DNA sequences related to the pathogenesis of HS. Biochemical and protein analyses have shown these isolates to be similar, but reports indicate that they have differences in pathogenicity. The subtracted inserts were screened against genomic DNA from a wide range of P multocida isolates, with two distinct fragments demonstrating specific hybridisation with Carter type B isolates that cause HS. No identity was observed with either Carter type E isolates or non-HS type B strains. The clones were sequenced and a search of the GenBank database revealed significant identity of the clone A3b (296 nt) to P haemolytica lipoprotein, whereas there was no significant identity with 6b (956 nt). Both these fragments had a high level of identity (72.8 to 76.9 per cent) to the H influenzae Rd genome.


Asunto(s)
Infecciones por Pasteurella/veterinaria , Pasteurella multocida/clasificación , Pasteurella multocida/genética , Animales , Secuencia de Bases , Búfalos , Bovinos , Enfermedades de los Bovinos , Pollos , Clonación Molecular , ADN Bacteriano/análisis , Genoma Bacteriano , Humanos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Infecciones por Pasteurella/microbiología , Pasteurella multocida/aislamiento & purificación , Enfermedades de las Aves de Corral , Ovinos , Enfermedades de las Ovejas , Porcinos , Enfermedades de los Porcinos , Regiones Terminadoras Genéticas , Pavos
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