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1.
BMC Cancer ; 24(1): 509, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654280

RESUMEN

BACKGROUND: Glioblastoma is a malignant and aggressive type of central nevous system malignancy characterized by many distinct biological features including extensive hypoxia. Hypoxia in glioblatoma associates with complex signaling patterns including activation of several pathways such as MAPK, PI3K-AKT/mTOR and IL-6/JAK/STAT3 with the master regulator HIF-1, which in turn drive particular tumor behaviors determining, in the end, treatment outcomes and patients fate. Thus, the present study was designed to investigate the expression of selected hypoxia related factors including STAT3 in a small set of long-term surviving glioma patients. METHODS: The expression of selected hypoxia related factors including STAT3 was evaluated in a time series of formalin fixed paraffin embedded and cryopreserved glioma samples from repeatedly resected patients. In addition, comparative studies were also conducted on primary glioma cells derived from original patient samples, stabilized glioma cell lines and tumor-xenograft mice model. Obtained data were correlated with clinical findings too. RESULTS: Glioblastoma samples of the analyzed patients displayed heterogeneity in the expression of hypoxia- related and EMT markers with most interesting trend being observed in pSTAT3. This heterogeneity was subsequently confirmed in other employed models (primocultures derived from glioblastoma tissue resections, cryopreserved tumor specimens, stabilized glioblastoma cell line in vitro and in vivo) and concerned, in particular, STAT3 expression which remained stable. In addition, subsequent studies on the role of STAT3 in the context of glioblastoma hypoxia demonstrated opposing effects of its deletion on cell viability as well as the expression of hypoxia and EMT markers. CONCLUSIONS: Our results suport the importance of STAT3 expression and activity in the context of hypoxia in malignant glioblastoma long-term surviving glioma patients while emphasizing heterogeneity of biological outcomes in varying employed tumor models.


Asunto(s)
Glioma , Factor de Transcripción STAT3 , Factor de Transcripción STAT3/metabolismo , Humanos , Animales , Ratones , Glioma/metabolismo , Glioma/patología , Glioma/genética , Masculino , Femenino , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Anciano , Adulto , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/genética , Regulación Neoplásica de la Expresión Génica , Hipoxia/metabolismo
2.
Diagnostics (Basel) ; 13(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37568909

RESUMEN

Histological identification of dispersed glioma cells in small biopsies can be challenging, especially in tumours lacking the IDH1 R132H mutation or alterations in TP53. We postulated that immunohistochemical detection of proteins expressed preferentially in gliomas (EGFR, MEOX2, CD34) or during embryonal development (SOX11, INSM1) can be used to distinguish reactive gliosis from glioma. Tissue microarrays of 46 reactive glioses, 81 glioblastomas, 34 IDH1-mutant diffuse gliomas, and 23 gliomas of other types were analysed. Glial neoplasms were significantly more often (p < 0.001, χ2) positive for EGFR (34.1% vs. 0%), MEOX2 (49.3% vs. 2.3%), SOX11 (70.5% vs. 20.4%), and INSM1 (65.4% vs. 2.3%). In 94.3% (66/70) of the glioblastomas, the expression of at least two markers was observed, while no reactive gliosis showed coexpression of any of the proteins. Compared to IDH1-mutant tumours, glioblastomas showed significantly higher expression of EGFR, MEOX2, and CD34 and significantly lower positivity for SOX11. Non-diffuse gliomas were only rarely positive for any of the five markers tested. Our results indicate that immunohistochemical detection of EGFR, MEOX2, SOX11, and INSM1 can be useful for detection of glioblastoma cells in limited histological samples, especially when used in combination.

3.
Cas Lek Cesk ; 149(7): 337-9, 2010.
Artículo en Checo | MEDLINE | ID: mdl-20925278

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) affects between 4-10% women of fertile age and is often connected with insulin resistance. We aimed to ascertain the prevalence of metabolic syndrome in Czech women with PCOS and to describe relations of different features of metabolic syndrome with insulin sensitivity. METHODS AND RESULTS: 179 women with PCOS. Clinical examination was done and blood lipid spectrum was measured. Euglycaemic hyperinsulinaemic clamp was done in 114 subjects. Metabolic syndrome (according to ATP III criteria) was detected in 28.7% women. The most frequent features were an increased waist circumference, decreased concentration of HDL - cholesterol (both in 96%), and increased blood pressure (88%). Increased triglycerides (49%) and impaired fasting blood glucose or diabetes mellitus type 2 (37.3%) were less common. The average insulin sensitivity described as corrected glucose disposal (Mk) was 34.9 +/- 12.70 micromol/kg/min. The most tight correlations was that of Mk and waist circumference (r = -0.896), weight (r = -0.875) and BMI (r = -0.844). CONCLUSION: The increased risk of metabolic syndrome and the decreased insulin sensitivity in polycystic ovary syndrome is tightly connected with obesity, especially with its abdominal type.


Asunto(s)
Síndrome Metabólico/complicaciones , Síndrome del Ovario Poliquístico/complicaciones , Femenino , Técnica de Clampeo de la Glucosa , Humanos , Resistencia a la Insulina , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/metabolismo , Síndrome del Ovario Poliquístico/metabolismo
4.
Cas Lek Cesk ; 149(11): 526-32, 2010.
Artículo en Checo | MEDLINE | ID: mdl-21391351

RESUMEN

BACKGROUND: The disposition index represents insulin secretion related to the degree of insulin sensitivity, being constant for given degree of glucose tolerance. The aim of this study is to discern genetic determinants influencing the value of disposition index, e.g. predisposition to glucose intolerance. METHODS AND RESULTS: Two hundred and four non-diabetic subjects with varied glucose tolerance were divided into groups according to the values of disposition index. Glucose and lipid metabolism, anthropometric parameters and family history of type 2 diabetes mellitus (DM2) were examined. The genotype frequency of candidate genes was compared between the groups of individuals within the lowest (Q1) and the highest (Q4) quartiles of the disposition index values. Those groups were not different concerning age and female to male ratio. Fasting and stimulated parameters of glucose metabolism and lipid profile were worse in group Q1 compared to group Q4. Group Q1 is characterized with higher number of individuals with metabolic syndrome and family history of DM2. The examination of candidate genes revealed the differences in genotype frequency of B2AR (rs1042714), PPARA (rs1800206), KCNJ11 (rs5219), and SLC30A8 (rs13266634) between groups Q1 and Q4. CONCLUSIONS: Low value of disposition index is related to the deterioration of glucose tolerance and other signs of metabolic syndrome. It is associated with genes affecting insulin secretion and genes related to energy metabolism and obesity.


Asunto(s)
Intolerancia a la Glucosa/genética , Insulina/genética , Adulto , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Estudios de Asociación Genética , Intolerancia a la Glucosa/fisiopatología , Humanos , Insulina/metabolismo , Insulina/fisiología , Resistencia a la Insulina/genética , Resistencia a la Insulina/fisiología , Secreción de Insulina , Masculino , Persona de Mediana Edad
5.
Cas Lek Cesk ; 149(11): 520-5, 2010.
Artículo en Checo | MEDLINE | ID: mdl-21391350

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrinopathy which is characterized by ovarian androgen excess. PCOS has a strong genetic component but the pathogenetic mechanisms responsible for hyperandrogenemia are still unknown. The CYP11A1 encodes the cholesterol side-chain cleavage enzyme that catalyzes the first and rate-limiting step of steroidogenesis. A promoter polymorphism (TTTTA)n CYP11A1 has been reported to be related to the risk of PCOS but the results were controversial. METHODS AND RESULTS: We determined this polymorphism in a cohort of 256 PCOS and 109 healthy control women. Using two models (dominant model for allele with 4 repeats and dominant model for long alleles, i.e. 7 and more repeats) we did not find either the difference in allele and genotype distribution between PCOS and controls or the influence of polymorphism on serum testosterone and androstendione levels. However, the PCOS carriers of long alleles had lower FSH, total- and LDL-cholesterol compared to the carriers of short alleles (p = 0.007; p = 0.02; p = 0.02, ANOVA). In controls, the non-carriers of allele with 4 repeats had significantly higher DHEA-S (p = 0.02, ANOVA) levels than the carriers of allele with 4 repeats. CONCLUSIONS: Despite of some associations found, it seems that the promoter variability of CYP11A1 does not play a key role in the pathogenesis of PCOS.


Asunto(s)
Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Repeticiones de Microsatélite/genética , Síndrome del Ovario Poliquístico/genética , Polimorfismo Genético , Regiones Promotoras Genéticas/genética , Adulto , Femenino , Genotipo , Hormonas/sangre , Humanos , Síndrome del Ovario Poliquístico/sangre
6.
Gynecol Endocrinol ; 25(9): 597-602, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19572227

RESUMEN

AIM: To study the impact of family history (FH) of type 2 diabetes mellitus on beta-cell compensatory mechanism in women with polycystic ovary syndrome (PCOS). SUBJECTS AND METHODS: A total of 70 women with PCOS, 14 with first-degree relative with type 2 diabetes mellitus (T2DM) (FH+), 56 with negative FH of T2DM (FH-) and 72 age and BMI matched control healthy women (CNT) underwent oral glucose tolerance test (OGTT). Insulin resistance was evaluated as oral glucose index (OGIS); insulin and C-peptide secretion as the insulinogenic index in 30th min of OGTT. RESULTS: Fasting blood glucose levels were significantly higher in FH+ than in FH- (p < 0.05). Fasting insulin was higher in FH+ than in CNT (p < 0.05). Fasting C-peptide was significantly higher in both FH- and FH+ than in CNT (p < 0.05 and p < 0.01, respectively). OGIS was lower in FH+ than in FH- or in CNT (p < 0.05). Insulinogenic index calculated from C-peptide values (II-Cp) was lower in FH+ than in CNT (p < 0.05). Adaptation index calculated from the values of OGIS and insulinogenic index was significantly lower in FH+ than in CNT or in FH- (p < 0.0001 and p < 0.01, respectively). CONCLUSIONS: Insulin resistance and defective early-phase insulin secretion is present only in those PCOS-affected subjects who had positive FH of T2DM.


Asunto(s)
Células Secretoras de Insulina/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adulto , Análisis de Varianza , Área Bajo la Curva , Glucemia/genética , Glucemia/metabolismo , Índice de Masa Corporal , Proteína C-Reactiva/genética , Proteína C-Reactiva/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/genética , Insulina/metabolismo , Resistencia a la Insulina/genética , Células Secretoras de Insulina/fisiología , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/fisiopatología , Testosterona/metabolismo
7.
Appl Immunohistochem Mol Morphol ; 14(2): 166-72, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16785784

RESUMEN

Pms2 protein is a component of the DNA mismatch repair complex responsible both for post-replication correction of DNA nucleotide mispairs and for early steps in apoptosis. Germline mutations in DNA mismatch repair genes give rise to hereditary non-polyposis colon cancer, which accounts for about 4% of colon cancers. However, little is known about the expression of mismatch repair proteins in relation to sporadic colon cancer, which accounts for the great majority of colon cancers. Multiple samples were taken from the non-neoplastic flat mucosa of colon resections from patients with no colonic neoplasia, a tubulovillous adenoma, or an adenocarcinoma. Expression of Pms2 was assessed using semiquantitative immunohistochemistry. Apoptosis was assessed in polychrome-stained epoxy sections using morphologic criteria. Samples from patients without colonic neoplasia had moderate to strong staining for Pms2 in cell nuclei at the base of crypts, while samples from 2 of the 3 colons with a tubulovillous adenoma, and from 6 of the 10 colons with adenocarcinomas, showed reduced Pms2 expression. Samples from patients with an adenocarcinoma that had reduced Pms2 expression also exhibited reduced apoptosis capability in nearby tissue samples, evidenced when this paired tissue was stressed ex vivo with bile acid. Reduced Pms2 expression in the colonic mucosa may be an early step in progression to colon cancer. This reduction may cause decreased mismatch repair, increased genetic instability, and/or reduced apoptotic capability. Immunohistochemical determination of reduced Pms2 expression, upon further testing, may prove to be a promising early biomarker of risk of progression to malignancy.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Apoptosis , Biomarcadores de Tumor/metabolismo , Neoplasias del Colon/patología , Enzimas Reparadoras del ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación hacia Abajo , Mucosa Intestinal/patología , Neoplasias del Colon/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto , Valor Predictivo de las Pruebas
8.
Obes Facts ; 9(6): 410-423, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27951535

RESUMEN

OBJECTIVE: To compare the effects of biliopancreatic diversion (BPD) and laparoscopic gastric banding (LAGB) on insulin sensitivity and secretion with the effects of laparoscopic gastric plication (P). METHODS: A total of 52 obese women (age 30-66 years) suffering from type 2 diabetes mellitus (T2DM) were prospectively recruited into three study groups: 16 BPD; 16 LAGB, and 20 P. Euglycemic clamps and mixed meal tolerance tests were performed before, at 1 month and at 6 months after bariatric surgery. Beta cell function derived from the meal test parameters was evaluated using mathematical modeling. RESULTS: Glucose disposal per kilogram of fat free mass (a marker of peripheral insulin sensitivity) increased significantly in all groups, especially after 1 month. Basal insulin secretion decreased significantly after all three types of operations, with the most marked decrease after BPD compared with P and LAGB. Total insulin secretion decreased significantly only following the BPD. Beta cell glucose sensitivity did not change significantly post-surgery in any of the study groups. CONCLUSION: We documented similar improvement in insulin sensitivity in obese T2DM women after all three study operations during the 6-month postoperative follow-up. Notably, only BPD led to decreased demand on beta cells (decreased integrated insulin secretion), but without increasing the beta cell glucose sensitivity.


Asunto(s)
Cirugía Bariátrica/métodos , Desviación Biliopancreática/métodos , Diabetes Mellitus Tipo 2/cirugía , Resistencia a la Insulina , Insulina/metabolismo , Obesidad Mórbida/cirugía , Adulto , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Humanos , Secreción de Insulina , Células Secretoras de Insulina/fisiología , Laparoscopía/métodos , Persona de Mediana Edad , Obesidad Mórbida/complicaciones , Obesidad Mórbida/metabolismo , Resultado del Tratamiento
9.
J Steroid Biochem Mol Biol ; 158: 157-177, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26704533

RESUMEN

Alzheimer's disease (AD) represents more than half of total dementias. Various factors including altered steroid biosynthesis may participate in its pathophysiology. We investigated how the circulating steroids (measured by GC-MS and RIA) may be altered in the presence of AD. Sixteen women with AD and 22 age- and BMI-corresponding controls aged over 65 years were enrolled in the study. The steroid levels (47 steroids and steroid polar conjugates) and their ratios in AD female patients indicated increased CYP11A1 activity, weakened activity of the CYP17A1C17,20 lyase metabolic step and attenuated sulfotransferase SULT2A1 activity at higher activity of the CYP17A1 17-hydroxylase step. The patients showed diminished HSD3B2 activity for C21 steroids, abated conversion of 17-hydroxyprogesterone to cortisol, and significantly elevated cortisol. The women with AD had also attenuated steroid 7α-hydroxylation forming immunoprotective Δ(5)-C19 steroids, attenuated aromatase activity forming estradiol that induces autoimmunity and a shift from the 3ß-hydroxy-5α/ß-reduced C19 steroids to their neuroinhibitory and antiinflammatory GABAergic 3α-hydroxy- counterparts and showed higher levels of the 3α-hydroxy-5α/ß-reduced C21 steroids and pregnenolone sulfate (improves cognitive abilities but may be both protective and excitotoxic). Our preliminary data indicated functioning of alternative "backdoor" pathway in women with AD showing higher levels of both 5α/ß-reduced C21 steroids but reduced levels of both 5α/ß-reduced C21 steroids, which implied that the alternative "backdoor" pathway might include both 5α- and 5ß-reduced steroids. Our study suggested relationships between AD status in women based on the age of subjects and levels of 10 steroids measured by GC-MS.


Asunto(s)
Enfermedad de Alzheimer/sangre , Hormonas/sangre , Anciano , Enfermedad de Alzheimer/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Oxidorreductasas/metabolismo , Progesterona Reductasa/metabolismo , Sulfotransferasas/metabolismo , Zona Reticular/metabolismo
10.
J Histochem Cytochem ; 53(2): 229-35, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15684335

RESUMEN

Apoptosis competence is central to the prevention of cancer. Frequency of apoptotic cells, after a sample of colonic tissue is stressed, can be used to gauge apoptosis competence and, thus, possible susceptibility to colon cancer. The gold standard for assessment of apoptosis is morphological evaluation, but this requires an experienced microscopist. Easier-to-use immunohistochemical markers of apoptosis, applicable in archived paraffin-embedded tissue, have been commercially developed. Potentially useful apoptosis markers include cleaved cytokeratin-18 (c-CK18), cleaved caspase-3 (c-cas-3), cleaved lamin A (c-lam-A), phosphorylated histone H2AX (gammaH2AX), cleaved poly(ADP ribose) polymerase (c-PARP), and translocation of apoptosis-inducing factor (AIF). When tissue samples from freshly resected colon segments were challenged ex vivo with the bile acid deoxycholate, approximately 50% of goblet cells became apoptotic by morphologic criteria. This high level of morphologic apoptosis allowed quantitative comparison with the usefulness and specificity of immunohistochemical markers of apoptosis. The antibody to c-CK18 was almost as useful and about as specific as morphology for identifying apoptotic colonic epithelial cells. Antibodies to c-cas-3, c-lam-A, and gammaH2AX, though specific for apoptotic cells, were less useful. The antibody to c-PARP, though specific for apoptotic cells, had low usefulness, and the antibody to AIF was relatively nonspecific, under our conditions.


Asunto(s)
Apoptosis , Colon/patología , Mucosa Intestinal/patología , Biomarcadores/metabolismo , Colon/metabolismo , Neoplasias del Colon/patología , Ácido Desoxicólico/farmacología , Humanos , Inmunohistoquímica , Técnicas In Vitro , Mucosa Intestinal/metabolismo
11.
Clin Cancer Res ; 10(6): 2020-8, 2004 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15041721

RESUMEN

PURPOSE: Barrett's esophagus (BE) is a common premalignant lesion of the distal part of the esophagus that arises as a consequence of chronic duodenogastroesophageal reflux. Interleukin (IL)-6 is a pleiotropic cytokine that regulates immune defense mechanisms and hematopoiesis. In addition, IL-6 may also be involved in malignant transformation and tumor progression. IL-6 has been shown to inhibit apoptosis. The major aim of this study was to evaluate expression of IL-6 in BE at the protein and mRNA levels. In addition, we tested whether proteins that are associated with IL-6 signaling, phosphorylated signal transducer and activator of transcription 3 and two antiapoptotic proteins, Bcl-x(L) and Mcl-1, are also expressed in the same tissues. EXPERIMENTAL DESIGN: Biopsies of duodenum, BE, and squamous epithelium were evaluated by using a human cytokine protein array, ELISA, real-time PCR, and immunohistochemistry. RESULTS: Increased IL-6 levels were found to be secreted from BE tissue compared with duodenum or squamous epithelium from sites adjacent or 5 cm away from the BE lesion. IL-6 mRNA was also elevated in BE compared with duodenum or squamous epithelium in five of seven patients. Immunohistochemical studies confirmed IL-6 expression in intestinal glandular epithelium in BE tissue. Activated signal transducer and activator of transcription 3, Mcl-1, and Bcl-x(L) are present at higher levels in BE glands, with lower levels being found in duodenum or squamous epithelium CONCLUSIONS: These data, taken together, suggest that elevated IL-6 levels in BE may contribute to the development of apoptosis resistance, thereby placing this epithelium at higher risk of developing malignancy.


Asunto(s)
Esófago de Barrett/genética , Interleucina-6/genética , Adulto , Anciano , Esófago de Barrett/inmunología , Transformación Celular Neoplásica , Duodeno/inmunología , Neoplasias Esofágicas/epidemiología , Regulación de la Expresión Génica/genética , Humanos , Inmunohistoquímica , Interleucina-6/metabolismo , Mucosa Intestinal/inmunología , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Factores de Riesgo
12.
Mol Cancer Ther ; 1(3): 185-95, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12467213

RESUMEN

Imexon is an aziridine-containing iminopyrrolidone with selective growth-inhibitory potency for multiple myeloma. Our previous research indicates that imexon induces mitochondrial alterations, oxidative stress, and apoptosis. This drug represents an interesting model drug with a nonmyelosuppressive profile to study the basic mechanisms leading to antitumor activity and resistance. The major purpose of this study was to characterize an imexon-resistant RPMI8226/I cell line that was developed from RPMI8226 cells by continuous exposure to imexon. No significant differences were observed in the sensitivity to several cytotoxic drugs, including mitoxantrone, mitomycin C, melphalan, methotrexate, cytarabine, cisplatin, vincristine, and paclitaxel, in the imexon-resistant cells. However, RPMI8226/I cells were cross-resistant to arsenic trioxide, doxorubicin, fluorouracil, etoposide, irinotecan, and especially IFN-alpha. The data from DNA microarray and Western blot analyses indicated that the levels of antiapoptotic proteins Bcl-2 and thioredoxin-2, which reside mainly in the mitochondria, are increased in RPMI8226/I cells. In addition, increased levels of lung resistance protein were detected in imexon-resistant cells. Expression of P-glycoprotein was not detected in RPMI8226/I cells. No loss of mitochondrial membrane potential or increase in the levels of reactive oxygen species was observed in RPMI8226/I cells after exposure to imexon; however, the levels of glutathione are increased in the RPMI8226/I cells. Transmission electron microscopy revealed significant changes in the mitochondrial morphology of RPMI8226/I cells, whereas no ultrastructural changes were observed in other cellular compartments. Imexon-resistant RPMI8226/I myeloma cells appear to have a unique mechanism of resistance that is associated with morphological alterations of mitochondria, increased protection against oxidative stress, elevated levels of glutathione, and enhanced expression of antiapoptotic mitochondrial proteins.


Asunto(s)
Resistencia a Antineoplásicos , Hexanonas/farmacología , Mieloma Múltiple/patología , Apoptosis/efectos de los fármacos , Grupo Citocromo c/metabolismo , ADN/efectos de los fármacos , ADN/metabolismo , Citometría de Flujo , Glutatión/metabolismo , Humanos , Concentración 50 Inhibidora , Potenciales de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Mieloma Múltiple/metabolismo , Proteínas de Neoplasias/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Estrés Oxidativo/efectos de los fármacos , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Tiorredoxinas/metabolismo , Células Tumorales Cultivadas/patología
13.
J Clin Endocrinol Metab ; 89(6): 2942-5, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15181081

RESUMEN

The aim of our study was to compare insulin sensitivity in lean and obese European polycystic ovary syndrome (PCOS) women with lean healthy women. We performed the euglycemic hyperinsulinemic clamp in 83 women with PCOS [53 lean with body mass index (BMI) of 21.5 +/- 1.8 kg/m2 and 30 obese with BMI of 29.6 +/- 3.7 kg/m2] and in 15 healthy women with BMI of 21.6 +/- 1.8 kg/m2 to determine glucose disposal (M) and the insulin sensitivity index (ISI). Statistical evaluation was done using Kruskal-Wallis ANOVA followed by Kruskal-Wallis multiple-comparison z-value test. The basal blood glucose was significantly higher in lean and obese PCOS women than in controls (P < 0.02). Fasting insulin was significantly higher in both lean and obese PCOS women than in controls (P < 0.000001). Obese PCOS women were more insulin resistant than controls (P < 0.02 for M and P < 0.0008 for ISI); lean PCOS women did not differ from controls in M or ISI. Posthepatic insulin delivery was significantly higher in both lean and obese PCOS women compared with controls (P < 0.000008). We conclude that lean PCOS women are not more insulin resistant than healthy controls. Insulin hypersecretion, on the other hand, is present even in lean PCOS women.


Asunto(s)
Resistencia a la Insulina , Obesidad/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adulto , Glucemia , Peso Corporal , Femenino , Técnica de Clampeo de la Glucosa , Humanos , Obesidad/complicaciones , Síndrome del Ovario Poliquístico/complicaciones
14.
Cancer Lett ; 177(2): 129-44, 2002 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-11825660

RESUMEN

Bile acids are promoters of colon cancer; however, the mechanism(s) of action of this tumor promoter are largely unknown. Bile acids induce apoptosis in colon epithelial cells and it is probable that the modulation of apoptosis contributes, in part, to colon carcinogenesis. We tested the hypothesis that damage to mitochondria is an upstream event in sodium deoxycholate (NaDOC)-induced apoptosis and that a pro-oxidant state of the cell favors survival. NaDOC-induced damage to mitochondria was assessed by a decrease in mitochondrial membrane potential using flow cytometry and an increase in megamitochondria formation using transmission electron microscopy. We found that inhibition of mitochondrial complexes I and II with rotenone and thenoyltrifluoroacetone, respectively, dramatically protected HT-29 cells against NaDOC-induced apoptosis. Antioxidants (e.g. lazaroids U-74389G and U-8389G), however, sensitized cells to NaDOC-induced apoptosis, in spite of a reduction in reactive oxygen/nitrogen species. Lazaroid pre-treatment caused a marked decrease in NaDOC-induced activation of the anti-apoptotic transcription factor, NF-kappaB, which may provide the basis for the sensitization to apoptosis caused by these antioxidants. Inhibitors of arachidonic acid metabolism (e.g. esculetin, sulindac sulfide, NS-398) also sensitized HT-29 cells to NaDOC-induced apoptosis. These results indicate that the life/death decision is the result of a shift in the balance between specific anti-apoptotic and pro-apoptotic factors, respectively, that may have significance to colon carcinogenesis.


Asunto(s)
Apoptosis , Ácido Araquidónico/metabolismo , Ácido Desoxicólico/farmacología , Mitocondrias/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Succinato Deshidrogenasa/metabolismo , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Cromanos/farmacología , Humanos , Piperazinas/farmacología , Pregnatrienos/farmacología , Células Tumorales Cultivadas
15.
Chem Biol Interact ; 145(1): 53-66, 2003 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-12606154

RESUMEN

Epidemiologic studies indicate that environmental (smoking) and dietary factors (high fat) contribute to carcinogenesis in many organ systems. The aim of our study was to test the hypothesis that nicotine, a component of cigarette smoke, and sodium deoxycholate (NaDOC), a cytotoxic bile salt that increases in concentration in the gastrointestinal tract after a high fat meal, induce similar cellular stresses and that nicotine may enhance some of the NaDOC-induced stresses. We found that nicotine, at 0.8 microM, the very low sub-micromolar level occurring in the tissues of smokers: (1). increases oxidative stress; (2). activates NF-kappaB, a redox-sensitive transcription factor; (3). activates the 78 kD glucose regulated protein promoter, an indication of endoplasmic reticulum stress; (4). induces apoptosis; (5). enhances the ability of NaDOC to activate the 153 kD growth arrest and DNA damage promoter, an indication of increased genotoxic stress; and (6). enhances the ability of NaDOC to activate the xenobiotic response element. Our findings have applicability to G.I. cancer, in general, since smoking is a risk factor in the development of esophageal, pancreatic, gastric and colon cancer, and these cancers are also promoted by bile acids.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteínas Portadoras/metabolismo , Ácido Desoxicólico/toxicidad , Proteínas de Choque Térmico , Chaperonas Moleculares/metabolismo , FN-kappa B/metabolismo , Nicotina/farmacología , Estrés Oxidativo/efectos de los fármacos , Proteínas Potenciadoras de Unión a CCAAT/genética , Cloranfenicol O-Acetiltransferasa/genética , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/patología , Daño del ADN , Chaperón BiP del Retículo Endoplásmico , Ensayo de Inmunoadsorción Enzimática , Humanos , Potenciales de la Membrana/efectos de los fármacos , Mutágenos/toxicidad , Regiones Promotoras Genéticas , Factor de Transcripción CHOP , Factores de Transcripción/genética , Células Tumorales Cultivadas , Xenobióticos/toxicidad
17.
Endocrine ; 36(3): 419-24, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19826964

RESUMEN

Activating germline RET mutations are presented in patients with familial medullary thyroid carcinoma (FMTC) and multiple endocrine neoplasia (MEN) types 2A and 2B, whereas inactivating germline mutations in patients with Hirschsprung's disease (HSCR). The aim of this study was to evaluate genotype-phenotype correlations of the frequently discussed Tyr791Phe mutation in exon 13 of the RET proto-oncogene. Screening of three groups of patients was performed (276 families with medullary thyroid carcinoma (MTC), 122 families with HSCR, and 29 patients with pheochromocytoma). We found this mutation in 3 families with apparently sporadic MTC, 3 families with FMTC/MEN2, 1 patient with pheochromocytoma, and 3 families with HSCR. All gene mutation carriers have a silent polymorphism Leu769Leu in exon 13. In three families second germline mutations were detected: Cys620Phe (exon 10) in MEN2A family, Met918Thr (exon 16) in MEN2B family, and Ser649Leu (exon 11) in HSCR patient. Detection of the Tyr791Phe mutation in MEN2/MTC and also in HSCR families leads to the question whether this mutation has a dual character (gain-of-function as well as loss-of-function). A rare case of malignant pheochromocytoma in a patient with the Tyr791Phe mutation is presented. This study shows various clinical characteristics of the frequently discussed Tyr791Phe mutation.


Asunto(s)
Enfermedad/genética , Cresta Neural/patología , Proteínas Proto-Oncogénicas c-ret/genética , Adolescente , Adulto , Anciano , Sustitución de Aminoácidos/genética , Carcinoma Medular/genética , Niño , Familia , Femenino , Estudios de Asociación Genética , Mutación de Línea Germinal , Enfermedad de Hirschsprung/genética , Humanos , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple Tipo 2a/genética , Fenilalanina/genética , Polimorfismo de Nucleótido Simple/fisiología , Proto-Oncogenes Mas , Neoplasias de la Tiroides/genética , Tirosina/genética , Adulto Joven
18.
Eur J Endocrinol ; 159(2): 121-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18511472

RESUMEN

OBJECTIVE: Polycystic ovary syndrome (PCOS) has been linked to a high risk of type 2 diabetes mellitus. Disturbances in the secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) have been observed in states with impaired glucose regulation. This paper considers the secretion of GIP and GLP-1 after oral glucose load in a group of lean, glucose-tolerant PCOS women in comparison with age- and body mass index (BMI)-matched healthy women. DESIGN: Case control. METHODS: PCOS (n=21, 25.8+/-4.1 years, BMI 21.6+/-1.7 kg/m(2)) and control healthy women (CT, n=13, 28.5+/-7.2 years, BMI 20.3+/-2.5 kg/m(2)) underwent oral glucose tolerance test (OGTT) with blood sampling for glucose, insulin, C-peptide, total GIP, and active GLP-1. Insulin sensitivity was determined both at fasting and during the test. STATISTICS: Repeated measures ANOVA. RESULTS: Glucose levels and insulin sensitivity did not differ between PCOS and CT. PCOS had significantly higher levels of C-peptide (P<0.05) and tended to have higher insulin levels. The levels of total GIP were significantly higher in PCOS than in CT (P<0.001). Active GLP-1 levels exhibited a significantly different time-dependent pattern in PCOS (P<0.002 for PCOS versus time interaction). GLP-1 concentrations were similar in PCOS and CT in the early phase of OGTT and then reached significantly lower levels in PCOS than in CT at 180 min (P<0.05). CONCLUSIONS: Increased total GIP and lower late phase active GLP-1 concentrations during OGTT characterize PCOS women with higher C-peptide secretion in comparison with healthy controls, and may be the early markers of a pre-diabetic state.


Asunto(s)
Incretinas/sangre , Síndrome del Ovario Poliquístico/sangre , Adulto , Glucemia/análisis , Péptido C/sangre , Estudios de Casos y Controles , Femenino , Polipéptido Inhibidor Gástrico/sangre , Péptido 1 Similar al Glucagón/sangre , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Resistencia a la Insulina/fisiología , Factores de Tiempo
19.
Clin Chem Lab Med ; 45(5): 639-44, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17484627

RESUMEN

BACKGROUND: Diabetes mellitus type 2 (DM2) affects 10% of women with polycystic ovary syndrome (PCOS). We evaluated the sensitivity and specificity of clinical and fasting biochemical parameters in screening for impaired glucose tolerance (IGT) and DM2. METHODS: Women with PCOS [n=244, age 27.4+/-7.5 years, body mass index (BMI) 27.5+/-6.9 kg/m(2)] and healthy women (n=57, age 26.8+/-5.8 years, BMI 21.3+/-2.1 kg/m(2)) underwent basal blood sampling and an oral glucose tolerance test (oGTT). RESULTS: Insulin resistance was identified in 40.2% of PCOS women. Impaired fasting glucose (5.6-6.9 mmol/L) was found in 30 subjects (12.3%), but the oGTT revealed IGT in only six of these cases and DM2 in one subject. IGT was found in 23 (9.4%) and DM2 in four (1.6%) of the women with PCOS. The conventional upper limits for total cholesterol, triglycerides, systolic and diastolic blood pressure and fasting glucose revealed low sensitivity for the identification of impaired glucose metabolism. CONCLUSIONS: No single parameter nor any combination of them showed an accuracy sufficient for screening of IGT or DM2 in PCOS patients. All PCOS patients should be screened using an oGTT to identify disturbances in glucose metabolism.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/etiología , Intolerancia a la Glucosa/diagnóstico , Resistencia a la Insulina , Tamizaje Masivo/métodos , Síndrome del Ovario Poliquístico/complicaciones , Adulto , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Tamizaje Masivo/normas , Síndrome del Ovario Poliquístico/epidemiología , Valor Predictivo de las Pruebas , Prevalencia , Sensibilidad y Especificidad
20.
J Antimicrob Chemother ; 58(2): 401-7, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16735414

RESUMEN

BACKGROUND: The ESAC project, granted by DG SANCO of the European Commission, is an international network of surveillance systems, aiming to collect comparable and reliable data on antibiotic use in Europe. Data on outpatient antibiotic use were collected from 34 countries using the ATC/DDD methodology. METHODS: For the period 1997-2003, data on outpatient use of systemic antibiotics aggregated at the level of the active substance were collected and expressed in DDD (WHO, version 2004) per 1000 inhabitants per day (DID). Outpatient antibiotic (ATC J01) use in 25 European countries, able to deliver valid data, was analysed. RESULTS: Total outpatient antibiotic use in 2003 varied by a factor of 3 between the country with the highest (31.4 DID in Greece) and the country with the lowest (9.8 DID in the Netherlands) use. General use patterns in individual countries as well as trends during the period 1997-2003 are described in this paper, while major antibiotic classes (penicillins, cephalosporins, macrolides/lincosamides/streptogramins and quinolones) will be analysed in detail in separate papers. CONCLUSION: The ESAC project established for the first time a credible alternative to industry sources for the collection of internationally comparable data on antibiotic use in Europe, based on cooperation between regulatory authorities, scientific societies, health insurers and professional organizations. These data provide a tool for assessing public health strategies aiming to optimize antibiotic prescribing.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Utilización de Medicamentos/estadística & datos numéricos , Pacientes Ambulatorios , Utilización de Medicamentos/tendencias , Europa (Continente) , Humanos
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