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1.
Zhonghua Bing Li Xue Za Zhi ; 49(2): 156-161, 2020 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-32074729

RESUMEN

Objective: To evaluate the expression of p-AKT and p-mTOR, the key proteins in PI3K/AKT/mTOR pathway in pediatric Burkitt lymphoma (BL), and to investigate the clinical and prognostic significance. Methods: Fifty-eight cases of pediatric BL and thirty cases of reactive hyperplastic lymphadenitis (RH) were collected at Children's Hospital of Fudan University from September 2011 to July 2018. Paraffin sections of tissues were immune stained for p-AKT and p-mTOR, and the expression was assessed and correlated with the clinical features and prognosis. Results: A total of 58 cases were diagnosed and 6 cases lost the follow-up. Of the remaining 52 BL patients including 43 males and 9 females, the median age was 5 years (range: 2 to 14 years). Regarding to the correlation between the two biomarkers, Spearman test showed that p-mTOR was positively associated with the expression of p-AKT (r=0.759, P<0.001). Of all BL patients, the positive rates of p-AKT and p-mTOR were 62.1% (36/58) and 60.3%(35/58) respectively, both significantly higher than control group (P=0.011, P=0.035 respectively). The presence of p-AKT was significantly associated with higher lactate dehydrogenase (LDH≥573 IU/L) level in patients of the disease (P=0.006), while p-mTOR was increased both in the higher LDH and lower ratio of albumin to globulin (A/G) group (P=0.006, P=0.034 respectively). Expression of p-AKT and p-mTOR did not show any statistical correlation with sex, age, St.jude stage, tumor size, B-symptom present or not, number of extra-nodal sites or international prognostic index (IPI) (P>0.05). Fifty-two patients had a median follow-up of 40 months (range: 5-87 months). Univariate analysis showed that p-AKT expression was significant in predicting both inferior OS (5-year estimate, 72.7% vs. 94.7%, χ(2)=4.123, P=0.042) and PFS (5-year estimate, 66.7% vs. 94.7%, χ(2)=5.822, P=0.016). The 5-year OS rate was 71.0% (22/31) for the p-mTOR positive cohort of patients compared to 95.2% (17/21) for p-mTOR negative group (χ(2)=4.881, P=0.027); however, there was no statistical significance in 5-year PFS rate (P>0.05). Especially, the 5-year OS and PFS rate of p-AKT/p-mTOR double-positive group were significantly lower than negative control group (including absence of single p-AKT or p-mTOR expression, and absence of both) (OS: 69.0% vs. 95.7%, χ(2)=6.285, P=0.012; PFS: 65.5% vs. 91.3%, χ(2)=5.405, P=0.020). The results of multivariate COX proportional risk regression analysis indicated that p-AKT/p-mTOR double-positive, higher LDH and IPI score 3-5 were independent prognostic factors for both OS and PFS, and the bulky tumor (>10 cm) for PFS of pediatric BL. Conclusion: The expression of p-AKT and p-mTOR may be a potential reference for diagnosis and the independent prognostic indicators of pediatric BL.


Asunto(s)
Linfoma de Burkitt , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Fosfatidilinositol 3-Quinasas , Pronóstico , Proteínas Proto-Oncogénicas c-akt , Estudios Retrospectivos , Serina-Treonina Quinasas TOR
2.
Asian-Australas J Anim Sci ; 30(8): 1143-1149, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28111445

RESUMEN

OBJECTIVE: The objective of the present study was to determine whether mango saponin (MS) could be used as a feed additive in broiler chicks by evaluating growth performance, carcass characteristics, meat quality, and plasma biochemical indices. METHODS: A total of 216 1-d-old Arbor Acres male broiler chicks were randomly assigned into three dietary treatments supplemented with 0 (control), 0.14% (MS 0.14%), or 0.28% (MS 0.28%) MS. Each treatment had six replicates (cages) with 12 chicks each. The feeding trial lasted for six weeks. RESULTS: Compared with the control, dietary supplemented with 0.14% or 0.28% MS increased average daily weight gain of chicks in the grower (22 to 42 d) and the whole (1 to 42 d) phases, and the final body weight of chicks on d 42 was higher in MS supplemented groups (p<0.05). Lower L45 min* (lightness) and L24 h* values, lower b24 h* (yellowness) value, and higher a45 min* (redness) and a24 h* values of the breast muscle were observed in chicks fed with 0.28% MS on d 42 (p<0.05). The total antioxidant capacity in plasma increased in MS 0.14% group on d 21 (p<0.001). Lower contents of plasma total cholesterol and triglyceride were observed in chicks fed with 0.28% MS on d 21 and d 42, whereas the group supplemented with 0.14% MS only decreased plasma triglyceride content on d 21 (p<0.05). The glucose content in plasma decreased in MS 0.28% group on d 42 (p<0.001). CONCLUSION: Overall, MS could be used as a feed additive in broiler chicks, and the supplemental level of 0.28% MS in diet could improve growth performance, meat quality, and plasma lipid metabolism in broiler chicks.

3.
Zhonghua Yi Xue Za Zhi ; 97(48): 3787-3791, 2017 Dec 26.
Artículo en Chino | MEDLINE | ID: mdl-29325337

RESUMEN

Objective: To observe the effect of low dose naloxone combinewith ropivacaine for supraclavicular brachial plexus block. Methods: Seventy patients undergoing elective upper limb surgery were randomly divided into two groups, ropivacaine group (Group R, n=35) and naloxone group (Group N, n=35). An ultrasound guided technique was used in both two groups.The onset and duration time of sensory and motor blockade, visual analog score(VAS)of 3, 6, 12, 18, 24 h postoperatively, time of first request fordezocine, total amount of dezocine needed, incidence of nausea and vomiting postoperatively(PONV) and patients' satisfaction score for analgesia in 24 h after surgery were measured.At the same time, blood samples were taken before anesthesia, 6 h, 24 h after operation for inspecting the concentration of ß-endorphin(ß-EP)in plasma. Results: The duration of sensory and motor blockade, time of first request for dezocine in Group N were 736.0(713.5, 836.5), 514.5(491.3, 572.8), 708.5(683.2, 877.0)min, which were all prolonged compared to Group R(522.0(469.5, 606.5), 401.0(370.0, 458.5), 570.0(435.0, 618.5)min)(Z=-6.844, -6.758, -6.700, all P<0.01). The 6, 12, 18 h postoperatively VAS of Group N were 0, 5.0(3.0, 5.8), 5.0(5.0, 6.0)point. Among which the 6, 12 h postoperatively VAS of Group N were lower than that of Group R(1.0(1.0, 3.5), 6.0(6.0, 7.0)point)(Z=-6.596, -4.864, all P<0.01), while the 18 h postoperatively VAS was higher than that of Group R (5.0(4.0, 5.0)point)(Z=-2.603, P<0.01). Total amount of dezocine needed in Group N in 24 h after surgery was 7.5(5.0, 10.0)mg, which was lower than that of Group R(10.0(10.0, 15.0)mg)(Z=-3.449, P<0.01). The incidence of PONV after surgery in Group N was 21.9%, which was lower than that of Group R(45.5%)(χ(2)=4.034, P<0.05). Ptients' satisfaction score for analgesia in 24 h after surgery in Group N was 8.0(7.0, 8.0)point, which was higher than that of Group R(7.0(6.0, 7.0)point)(Z=-3.509, P<0.01). At 6 h postoperatively , the concentration of plasma ß-EP in Group N was(113.34±12.36)µg/L, lower than that of Group R((147.14±11.65)µg/L)(t=-7.694, P<0.01). Conclusion: Low dose naloxone combine with ropivacaine for supraclavicular brachial plexus block, prolong the duration of sensory and motor blockade without affecting the onset time.


Asunto(s)
Amidas/administración & dosificación , Anestésicos Locales/administración & dosificación , Bloqueo del Plexo Braquial , Naloxona/administración & dosificación , Brazo/cirugía , Plexo Braquial , Humanos , Dolor Postoperatorio , Ropivacaína
4.
Eur J Clin Microbiol Infect Dis ; 29(5): 551-4, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20213256

RESUMEN

This study was conducted to determine whether electrolysed acid water (EAW) increased the antibacterial effect of irrigating solution used in the management of chronic rhinosinusitis (CRS). One hundred CRS patients were recruited from April 2008 to February 2009. Four swab specimens were taken from the ipsilateral middle meatus of each patient and one was placed in a Thanswab tube, while the other three were each placed randomly in one of three glass tubes containing either 5 ml of EAW, distilled water or 70% alcohol. They were immediately sent to the laboratory for aerobic and anaerobic cultures. Bacteria grew from 36 specimens when they were placed in a Thanswab tube, from four when placed in a tube with EAW, 30 when placed in distilled water and two when placed in alcohol. The culture rate was significantly lower when the specimens were placed in a tube with EAW as compared with distilled water or in a Thanswab tube, but was not different compared with alcohol. The bacteria that grew from four specimens after first being processed by EAW were all anaerobes. This study showed that EAW exhibited an increased antibacterial effect on bacteria grown from the nasal discharge of CRS patients.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Cavidad Nasal/microbiología , Rinitis/microbiología , Sinusitis/microbiología , Adulto , Distribución de Chi-Cuadrado , Enfermedad Crónica , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad
5.
J Food Sci ; 73(7): H179-85, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18803715

RESUMEN

Mycelia of Antrodia cinnamomea (AC), an edible fungus native to Taiwan, were produced by submerged fermentation with various fermentation times in 250 mL, 5 and 500 L fermentors and were evaluated for the effect of fermentation products on the viabilities of Hep3B and HepG2 hepatoma cells and normal primary rat hepatocytes. The results showed that the ethanolic extracts of AC mycelia (from 250 mL fermentation for 8 wk and 5 and 500 L fermentations for 4 wk) possessed high antihepatoma activity. The IC(50) of ethanolic extract of AC mycelia fermented for 8 wk in a 250 mL fermentor against Hep3B and HepG2 cells were 82.9 and 54.2 microg/mL, respectively. Furthermore, the IC(50) for Hep3B and HepG2, treated with ethanolic extract of AC mycelia fermented for 4 wk in the 5 L fermentor were 48.7 and 3.8 microg/mL, respectively. Those treated with ethanolic extract of AC mycelia fermented for 4 wk in the 500 L fermentor were 36.9 and 3.1 microg/mL, respectively. No adverse effects of all samples on normal primary rat hepatocytes were observed.


Asunto(s)
Antineoplásicos/farmacología , Mezclas Complejas/farmacología , Hepatocitos/efectos de los fármacos , Micelio/química , Polyporales/química , Animales , Línea Celular Tumoral , Supervivencia Celular , Fermentación , Humanos , Peroxidación de Lípido , Masculino , Medicina Tradicional , Ratas , Ratas Sprague-Dawley , Taiwán , Factores de Tiempo
6.
Eur J Clin Microbiol Infect Dis ; 27(4): 253-7, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18183442

RESUMEN

This goal of this study was to demonstrate whether fungi were present in the ethmoid sinus in patients with chronic rhinosinusitis. Before surgery, swab specimens were collected from the middle meatus for conventional fungal cultures, and lavaged fluid was collected from the nasal cavity for fungal cultures by Ponikau's method. During surgery, tissue specimens were taken from the inferior turbinate and the anterior ethmoid sinus for conventional fungal cultures and detection of fungal DNA by polymerase chain reaction. The ethmoid sinus mucosa with coating mucus was also collected for fungal cultures by Ponikau's method. Among 53 specimens, three middle meatal specimens and 27 lavaged specimens (50.9%) grew fungi. Inferior turbinal mucosa did not grow fungi, but three ethmoid sinus specimens grew fungi by the conventional fungal culture method and by Ponikau's method. Alternaria DNA was detected in 42 inferior turbinal specimens (79.3%) and in 39 ethmoid sinus specimens (73.6%). Our study showed that although fungi were rarely cultured from the ethmoid sinus Alternaria DNA was detected in most of the ethmoid sinus mucosa.


Asunto(s)
Senos Etmoidales/microbiología , Sinusitis del Etmoides/microbiología , Hongos/clasificación , Adolescente , Adulto , Anciano , Enfermedad Crónica , Femenino , Hongos/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad
8.
Arch Virol ; 147(2): 273-84, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11890523

RESUMEN

Two humic-like substances, the oxidative polymer of protocatechuic acid (OP-PCA) and humic acid inhibit the in vitro replication of influenza virus A/WSN/33 (H1N1) in Madin-Darby canine kidney (MDCK) cells at concentrations of no cytotoxicity. The 50% inhibitory concentration (IC50) for OP-PCA was 6.59 +/- 1.02 microg/ml when the compound was added at the stage of viral adsorption. When OP-PCA was added after virus adsorption, the IC50 was 53.27 +/- 8.12 microg/ml. The IC50 for humic acid was 48.61 +/- 7.32 microg/ml and 55.27 +/- 5.46 microg/ml respectively when the compound was added at the stage of viral adsorption or post-adsorption. In spite of structural resemblance of these two compounds, they exhibit different actions of anti-flu. The OP-PCA inhibits virus-induced hemagglutination and low pH-induced cell-cell fusion. Humic acid inhibits the endonuclease activity of viral RNA polymerase. The monomer of PCA shows no inhibition on influenza virus replication.


Asunto(s)
Sustancias Húmicas/farmacología , Hidroxibenzoatos/farmacología , Virus de la Influenza A/efectos de los fármacos , Polímeros/farmacología , Replicación Viral/efectos de los fármacos , Animales , Línea Celular , Perros , Endonucleasas/efectos de los fármacos , Endonucleasas/metabolismo , Sustancias Húmicas/síntesis química , Sustancias Húmicas/química , Hidroxibenzoatos/química , Virus de la Influenza A/crecimiento & desarrollo , Riñón/citología , Oxidación-Reducción , Ensayo de Placa Viral , Proteínas Virales/biosíntesis
9.
Free Radic Res ; 35(4): 395-403, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11697136

RESUMEN

Aging is associated with impaired immunity and reduced host defenses. Mitochondrial bioenergetic dysfunctions and reduced antioxidative ability of immunocompetent cells may contribute to this phenomenon. In this study, 60 healthy volunteers of different age groups donated their blood after overnight fasting. Leukocytes were subjected to oxidative injuries by exposure to t-butylhydroperoxide, and were labeled with fluorochromes for measuring mitochondria transmembrane potential (delta psi m), membrane peroxidation and mitochondrial oxidant formation. delta psi m declined after t-butylhydroperoxide exposure, and the change was more prominent in leukocytes from older individuals. Cyclosporin A partly restored delta psi m, implying the contributing role of mitochondrial permeability transition pores. The mitochondrial depolarization was accompanied by increased oxidant formation and oxidation of pyridine nucleotides, which were more prominent in older subjects. The results support the view that the bioenergetic functions of mitochondria are more susceptible to oxidative injury in aged individuals. The decreased ability of leukocytes to resist oxidative stress may contribute to immunosenescence in humans.


Asunto(s)
Envejecimiento/fisiología , Leucocitos/metabolismo , Mitocondrias/fisiología , Adulto , Anciano , Línea Celular , Ciclosporina/farmacología , Femenino , Citometría de Flujo , Humanos , Inmunosupresores/farmacología , Leucocitos/efectos de los fármacos , Masculino , Potenciales de la Membrana/fisiología , Persona de Mediana Edad , Oxidación-Reducción , Estrés Oxidativo , terc-Butilhidroperóxido/farmacología
10.
J Am Coll Cardiol ; 38(6): 1693-700, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11704382

RESUMEN

OBJECTIVES: The purpose of this study was to examine the changes in leukocyte mitochondrial transmembrane potential (MTP) and its association with apoptosis in congestive heart failure (CHF). BACKGROUND: Congestive heart failure is a heterogeneous syndrome with multiple hemodynamic, neuroendocrine and immune abnormalities. Although edematous CHF may be associated with endotoxemia and increased cytokine production, peripheral blood leukocyte functions in advanced CHF remain unclear. METHODS: Thirty patients with acute decompensated CHF (mean age [+/- SEM] 74.9 +/- 3.1 years) and 20 healthy controls underwent determination of MTP, intracellular oxidants and apoptosis in three subsets of peripheral blood leukocytes. The measurements were repeated after the time of recompensation. RESULTS: Patients with acute CHF showed marked MTP reduction and increased intracellular oxidant formation in three subsets of leukocytes upon entry into the study. These changes were more prominent in patients with peripheral edema. The decline in MTP was correlated with the severity of the peripheral edema and plasma concentration of cortisol, nitrogen metabolites and tumor necrosis factor-alpha (p < 0.01). After clinical stabilization, MTP gradually recovered. Leukocytes underwent increased propensity of apoptosis one week after the time of recompensation. CONCLUSIONS: The mitochondrial depolarization and apoptosis of leukocytes in decompensated heart failure suggest that CHF is associated with severity-dependent impairments in leukocyte function. Accentuated hormonal and cytokine abnormalities and increased circulating oxidants may contribute to these changes. Early and aggressive management of advanced heart failure is helpful in the recovery of these immune abnormalities.


Asunto(s)
Apoptosis/fisiología , Insuficiencia Cardíaca/metabolismo , Leucocitos/metabolismo , Potenciales de la Membrana/fisiología , Mitocondrias/metabolismo , Anciano , Análisis de Varianza , Estudios de Casos y Controles , Fragmentación del ADN , Femenino , Citometría de Flujo , Insuficiencia Cardíaca/fisiopatología , Hemodinámica , Humanos , Masculino , Estudios Prospectivos , Estadísticas no Paramétricas
11.
Life Sci ; 69(11): 1269-84, 2001 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-11521751

RESUMEN

Humic acid (HA) is a fluorescent deep brown organic, polymeric compound composed of phenolic acid. Intraperitoneal injection of HA in rats induced testicular morphological changes including degeneration of the seminiferous tubule, reduction in the number of Sertoli cells and spermatogonia, and a loss of spermatids. It was suggested that Sertoli cells may be involved in the progression of testicular atrophy. In this study, we used a mouse Sertoli cell Line, TM4, to investigate the effect of HA on Sertoli cells and the mechanism of the testicular atrophy induced by HA. We found that the cell growth of TM4 cells were reduced in 1 to 4 days of HA exposure. FACScan analysis of the DNA content of HA-treated TM4 cells revealed that there was no sub-G1 peak, indicating that the TM4 cells did not commit to the programmed cell death. However, a large proportion of TM4 cells were arrested at the G1 phase. The percentage of TM4 cells at the G1 phase increased from 36% to 84% after HA treatment for 4 days. Western blot assay of HA-treated TM4 cells showed that the expression of cyclin D1 protein decreased while the expression of p27kiP1 protein increased. These results suggest that HA-induced testicular atrophy is linked in part to an inhibitory effect on the growth of Sertoli cells. This model may be useful in investigation of environmental agents inducing testicular atrophy.


Asunto(s)
Sustancias Húmicas/toxicidad , Células de Sertoli/efectos de los fármacos , Proteínas Supresoras de Tumor , Animales , Western Blotting , Recuento de Células , Proteínas de Ciclo Celular/metabolismo , División Celular/efectos de los fármacos , Línea Celular , Ciclina D1/biosíntesis , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , ADN/biosíntesis , Citometría de Flujo , Fase G1/efectos de los fármacos , Masculino , Ratones , Células de Sertoli/metabolismo , Células de Sertoli/patología
12.
Int J Cancer ; 93(1): 74-9, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11391624

RESUMEN

Human chromosome band 16q24 commonly undergoes loss of heterozygosity (LOH) in human hepatocellular carcinoma (HCC). To further localize the region of deletion on 16q24 and to evaluate the genetic role of 17-beta-HSD, which is near 16q24, in HCC, we examined the pattern of loss of heterozygosity in 88 HCC patients. DNAs from 88 pairs of HCCs and corresponding non-tumor parts were prepared. Loss of heterozygosity on chromosomes 16q24 was investigated by 11 sets of microsatellite markers. Mutation analysis of type II 17-beta-HSD was performed by automatic sequencing. LOH on 16q24 for at least 1 locus was found in 43 of the 88 tumor DNAs (49%). Three non-overlapping regions of frequent LOH were defined in these 43 tumors with partial deletions. The first region was between D16S516 loci and D16S507, encompassed by a 1-cM region, defined by the D16S504. The second region was defined by the 17HSDB2 locus between D16S505 and D16S422, encompassed approximately by a 1-cM region. The third region was between D16S520 and D16S413, defined by D16S3048, encompassed approximately by a 4-cM region. Homozygous deletions of any exons in 17HSDB2 gene were identified in 7 of 27 cases (26%). Automated sequencing analysis of 17HSDB2 failed to demonstrate mutations in any of these specimens. Our data suggest that the 17HSDB2 locus is a frequent target of deletion in HCC but the inactivation of 17HSDB2 may not involve sequence mutations. Furthermore, the presence of the other 2 frequent LOH regions suggest that the putative tumor suppressor genes at these locations might be involved in the development of HCC.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/genética , Carcinoma Hepatocelular/genética , Cromosomas Humanos Par 16 , Neoplasias Hepáticas/genética , Pérdida de Heterocigocidad , Mapeo Cromosómico , Análisis Mutacional de ADN , Cartilla de ADN , ADN de Neoplasias/genética , Marcadores Genéticos , Humanos , Repeticiones de Microsatélite/genética , Reacción en Cadena de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Taiwán
13.
Biochem Biophys Res Commun ; 283(4): 743-9, 2001 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-11350046

RESUMEN

Humic acid (HA), a potential toxin that has penetrated the drinking well water of blackfoot disease-endemic areas in Taiwan, has been implicated as an etiological factor of this disease. In this study, we investigated the effects of HA on the generation of reactive oxygen species (ROS) in cultured human umbilical vein endothelial cells (HUVECs). The generation of ROS was monitored by flow cytometry. Pretreatment of HUVECs with HA induced reactive oxygen species in a dose- and time-dependent manner. Xanthine oxidase inhibitor (Allopurinol), NADPH oxidase inhibitor (diphenylene iodomium) and calcium chelator (BAPTA) could not reduce the generation of ROS. Protein kinase C inhibitor (H7) could reduce the generation of ROS slightly, but the intracellular antioxidant glutathione monoethyl ester and the iron chelator desferrioxamine (DFO) could inhibit the generation of ROS completely. HA also enhanced the expression of ferritin and induced intracellular chelatable iron; however, HA reduced the expression of transferrin receptor. Pretreatment with DFO inhibited HA-mediated increases of ferritin synthesis and intracellular chelatable iron, but caused recovery of the inhibitory effect on transferrin receptor. Cotreatment with iron and HA induced more ROS and intracellular chelatable iron than iron or HA treatment alone. Furthermore, HA enhanced the accumulation of iron in endothelial cells. These data demonstrate that HA can increase the generation of ROS through enhancing the accumulation of intracellular iron. Taken together, our findings suggest that iron mediates HA-associated oxidative stress in endothelial cells, which may be a possible mechanism leading to atherothrombotic vascular injury observed for patients with blackfoot disease.


Asunto(s)
Arteriopatías Oclusivas/inducido químicamente , Sustancias Húmicas/farmacología , Hierro/metabolismo , Estrés Oxidativo , Arteriopatías Oclusivas/metabolismo , Células Cultivadas , Ferritinas/metabolismo , Humanos , Quelantes del Hierro/metabolismo , Receptores de Transferrina/metabolismo
14.
Free Radic Biol Med ; 29(2): 156-69, 2000 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10980404

RESUMEN

Glucose-6-phosphate dehydrogenase (G6PD) is involved in the generation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) and the maintenance of the cellular redox balance. The biological effects of G6PD deficiency in nucleated cells were studied using G6PD-deficient human foreskin fibroblasts (HFF). In contrast to that of normal HFF, the doubling time of G6PD-deficient cells increased readily from population doubling level (PDL) 15 to 63. This was accompanied by a significant increase in the percentage of G(1) cells. The slow-down in growth preceded an early entry of these cells into a nondividing state reminiscent of cellular senescence. These cells exhibited a significant increase in level of senescence-associated beta-galactosidase (SA-beta-gal) staining. The importance of G6PD activity in cell growth was corroborated by the finding that ectopic expression of active G6PD in the deficient cells prevented their growth retardation and early onset of senescence. Mechanistically, the enhanced fluorescence in dichlorofluorescin (H(2)DCF)-stained G6PD-deficient cells suggests the possible involvement of reactive oxygen species in senescence. Taken together, our results show that G6PD deficiency predisposes human fibroblasts to retarded growth and accelerated cellular senescence. Moreover, G6PD-deficient HFF provides a useful model system for delineating the effects of redox alterations on cellular processes.


Asunto(s)
Senescencia Celular , Fibroblastos/fisiología , Deficiencia de Glucosafosfato Deshidrogenasa/fisiopatología , Estrés Oxidativo , Fenómenos Fisiológicos de la Piel , Ciclo Celular , División Celular , Células Cultivadas , Fibroblastos/citología , Glucosafosfato Deshidrogenasa/metabolismo , Deficiencia de Glucosafosfato Deshidrogenasa/patología , Humanos , Recién Nacido , Cinética , Masculino , Especies Reactivas de Oxígeno/metabolismo , Valores de Referencia , Piel/citología , Piel/patología , Piel/fisiopatología , Telómero/genética , Transfección , beta-Galactosidasa/metabolismo
15.
J Toxicol Environ Health A ; 60(3): 215-30, 2000 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-10884168

RESUMEN

Blackfoot disease (BFD) is a peripheral arterial occlusive disease found among human inhabitants along the southwest coast of Taiwan. Well water used for drinking and cooking contains humic acid (HA), which may be a possible etiological factor. In this study, HA toxicity was investigated in human erythrocytes and was found to induce echinocytic formation. Morphological changes occurred in both a concentration- and time-dependent fashion. The presence of HA was also observed to facilitate the loading of erythrocytes with excess Ca(2+) (1 mM), which may have occurred following permeability changes in cell membranes, leading to echinocytic transformations. Sodium dodecyl sulfate (SDS) gel electrophoresis indicated that echinocyte formation was due to the oxidation of normal membrane proteins that were replaced by high-molecular-weight proteins. Humic acid also induced hemoglobin oxidation in erythrocytes. Data show that oxidative stress generated by HA as well as direct effects were exerted on the cytoskeleton of erythrocytes, and these may be significant factors in the etiology of BFD.


Asunto(s)
Quelantes/toxicidad , Deformación Eritrocítica/efectos de los fármacos , Sustancias Húmicas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Anemia/inducido químicamente , Canales de Calcio/efectos de los fármacos , Membrana Celular/fisiología , Eritrocitos/efectos de los fármacos , Hemoglobinas/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Oxidación-Reducción , Enfermedades Vasculares Periféricas/inducido químicamente , Permeabilidad
16.
FEBS Lett ; 475(3): 257-62, 2000 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-10869567

RESUMEN

Glucose-6-phosphate dehydrogenase (G6PD) plays an important role in cellular redox homeostasis, which is crucial for cell survival. In the present study, we found that G6PD status determines the response of cells exposed to nitric oxide (NO) donor. Treatment with NO donor, sodium nitroprusside (SNP), caused apoptosis in G6PD-deficient human foreskin fibroblasts (HFF1), whereas it was growth stimulatory in the normal counterpart (HFF3). Such effects were abolished by NO scavengers like hemoglobin. Ectopic expression of G6PD in HFF1 cells switched the cellular response to NO from apoptosis to growth stimulation. Experiments with 1H-¿1,2,4oxadiazolo¿4, 3-aquinoxalin-1-one and 8-bromo-cGMP showed that the effects of NO on HFF1 and HFF3 cells were independent of cGMP signalling pathway. Intriguingly, trolox prevented the SNP-induced apoptosis in HFF1 cells. These data demonstrate that G6PD plays a critical role in regulation of cell growth and survival.


Asunto(s)
Fibroblastos/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Óxido Nítrico/metabolismo , Apoptosis , Células Cultivadas , Fibroblastos/patología , Deficiencia de Glucosafosfato Deshidrogenasa/metabolismo , Deficiencia de Glucosafosfato Deshidrogenasa/patología , Humanos , Masculino , Donantes de Óxido Nítrico/farmacología , Nitroprusiato/farmacología , Oxidación-Reducción
17.
Toxicol Appl Pharmacol ; 166(1): 59-67, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10873719

RESUMEN

Humic acid (HA), a potential toxin when penetrating the drinking well water of blackfoot disease-endemic areas in Taiwan, has been implicated as one of the etiological factors of this disease. In this study, we investigated the effects of HA on the expression of human vascular endothelial-leukocyte adhesion molecules and the activation of nuclear factor kappa B (NF-kappaB) in cultured human umbilical vein endothelial cells (HUVECs). The expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin was monitored by flow cytometry. Pretreatment of HUVECs with HA inhibited the lipopolysaccharide (LPS)-induced expression of these three adhesion molecules in a dose- and time-dependent manner. Since NF-kappaB can regulate the expression of these adhesion molecules, NF-kappaB activation was assessed by electrophoretic mobility shift assay (EMSA). Our results reveal that the activation of NF-kappaB by LPS is suppressed by HA in a dose- and time-dependent manner. Furthermore, HA reduces NF-kappaB binding to DNA slightly, but completely inhibits the degradation of IkappaBalpha at a concentration of 100 microg/ml. Thus, all our data demonstrate that HA can inhibit the LPS-induced expression of adhesion molecules through the inhibition of NF-kappaB activation. HA may also suppress the immune or inflammatory reaction of HUVECs responsible for endotoxin, which could be one possible explanation for the causes of the infection and inflammation observed for patients with blackfoot disease. Our results also suggest that immune or inflammatory disturbance occurs for patients with blackfoot disease and that NF-kappaB may be a critical molecule in the pathogenesis of this disease.


Asunto(s)
Moléculas de Adhesión Celular/biosíntesis , Endotelio Vascular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Sustancias Húmicas/farmacología , Proteínas I-kappa B , Lipopolisacáridos/farmacología , FN-kappa B/antagonistas & inhibidores , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/genética , Células Cultivadas , Quelantes/farmacología , Proteínas de Unión al ADN/metabolismo , Interacciones Farmacológicas , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiología , Silenciador del Gen , Células HL-60 , Humanos , Inhibidor NF-kappaB alfa , FN-kappa B/genética
18.
Ann Rheum Dis ; 59(5): 338-41, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10784514

RESUMEN

OBJECTIVE: Superoxide anion radicals within the human body are regarded as a major cause of inflammation. However, their role in the pathogenesis of ankylosing spondylitis (AS) has not been well identified. This study aimed at investigating the relation between AS and the oxidative metabolism of phagocytes in whole blood. METHODS: 24 patients with classic AS were examined to determine their clinical status; complete blood count, erythrocyte sedimentation rate (ESR), and C reactive protein (CRP) were determined, and levels of the superoxide anion radicals in the patients with AS and 21 healthy subjects were assessed by the ultraweak chemiluminescence method. Subsequently, the relation between this disease and phagocytes was examined by using N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol-12-myristate-13-acetate (PMA) stimulants. RESULTS: In clinical assessments, patients with AS had abnormally raised serum CRP (>10 mg/l) and ESR (>15 mm/1st h) levels. In contrast with healthy subjects, patients with AS had significantly increased rates of superoxide anion radical production in their whole blood either in the resting state or with either fMLP or PMA stimulation. In addition, chemiluminescence maximum light intensity was significantly higher in patients with AS than in healthy subjects after fMLP or PMA stimulation. CONCLUSIONS: Our results suggest that the phagocytes of patients with AS are partly activated in the resting state, and are sensitive to fMLP or PMA stimulation. The priming of phagocytes in the bloodstream is likely to be a causative factor in the onset of AS.


Asunto(s)
Fagocitos/metabolismo , Espondilitis Anquilosante/sangre , Superóxidos/sangre , Adulto , Sedimentación Sanguínea , Proteína C-Reactiva/metabolismo , Humanos , Mediciones Luminiscentes , Masculino , Persona de Mediana Edad , N-Formilmetionina Leucil-Fenilalanina/farmacología , Fagocitos/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología
19.
Nutr Cancer ; 38(2): 200-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11525598

RESUMEN

To determine the enhancing effect of a whey protein isolate on the cytotoxicity of a potential anticancer drug, baicalein, the human hepatoma cell line Hep G2 was assigned to grow in different media for four days, and cell growth and apoptosis were investigated. The control group was grown in normal medium; the other three groups were grown in whey protein isolate (Immunocal) medium, baicalein medium, and a combination of Immunocal and baicalein. As indicated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, survival rate was significantly lower in cells grown in baicalein + Immunocal than in cells grown in baicalein alone. In contrast, there was no significant difference in survival rate of the cells grown in Immunocal. In the investigation of apoptosis, cells grown in baicalein + Immunocal showed a higher phosphatidylserine exposure, lower mitochondrial transmembrane potential, and nearly 13 times more cells undergoing apoptosis than cells grown in baicalein alone. We also demonstrated that Immunocal reduced glutathione (GSH) in Hep G2 cells by 20-40% and regulated the elevation of GSH, which was in response to baicalein. In conclusion, Immunocal seemed to enhance the cytotoxicity of baicalein by inducing more apoptosis; this increase in apoptotic cells may be associated with the depletion of GSH in Hep G2 cells. This is the first study to demonstrate, in vitro, that Immunocal may function as an adjuvant in cancer treatments.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Flavanonas , Flavonoides/farmacología , Proteínas de la Leche/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Quimioterapia Adyuvante , Medios de Cultivo , Sinergismo Farmacológico , Citometría de Flujo , Glutatión/efectos de los fármacos , Humanos , Cinética , Potenciales de la Membrana/efectos de los fármacos , Proteína de Suero de Leche
20.
Nutr Cancer ; 38(2): 287-95, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11525608

RESUMEN

This study has demonstrated that baicalein has anticancer effectiveness against human hepatoma cells. The dose response of baicalein in Hep G2 and Hep J2 cells indicates that baicalein decreased viability >90%. In comparison, baicalein had only minimal effects on the viability of control Chang liver cells. Flow cytometric analysis showed that baicalein inhibited the cell cycle of Hep G2 cells in the S phase. In addition, baicalein treatment resulted in a decreased mitochondrial transmembrane potential and damaged the integrity of the cell membrane. The TdT-mediated dUTP-biotin nick end labeling assay results indicated that baicalein elicited a significant increase of DNA fragmentation in Hep G2 cells after incubation for 48 hours. These results indicate that baicalein is an effective antihepatoma agent with minimal influence on noncancer cells. The effects of baicalein on Hep G2 cells include inhibition of the S phase of the cell cycle, dysfunction of mitochondria, and initiation of apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/patología , Flavanonas , Flavonoides/farmacología , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/tratamiento farmacológico , División Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Fragmentación del ADN , ADN de Neoplasias/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Flavonoides/uso terapéutico , Citometría de Flujo , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/fisiología , Fase S/efectos de los fármacos , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/patología
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