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1.
Prague Med Rep ; 114(2): 103-12, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23777801

RESUMEN

It should be expected that the hepatic blood flow increase in the cases with liver metastasis. We aimed to find out if there is a correlation between Doppler parameters and hepatic metabolic activity in oncology patients. 35 patients with hepatic metastases who were identified by 18F-fluorodeoxyglucose positron emission tomography scan and assessed with Doppler ultrasound were included in this prospective study. Patients with hepatic disease, cardiac dysfunction, dehydration, history of alcoholism, intake of antihypertensive or vasoactive medication were excluded. Volume flow of the proper hepatic artery and the portal vein were measured in the hepatoduodenal ligament by Doppler sonography. Doppler perfusion index (the ratio of the hepatic artery flow to the total liver blood flow) and flow volumes of 31 age matched subjects were compared. Both flow of the proper hepatic artery and portal vein were found to be significantly higher in patients with liver metastasis. The mean Doppler perfusion index value was 0.2 ± 0.13 in hepatic metastases whereas 0.13 ± 0.05 in control group. Doppler perfusion index was significantly higher in liver metastases (p=0.008). A positive correlation was found between the maximum standardized uptake value of the liver and flow volume of the proper hepatic artery (r=0.774, p=0). Blood flow of the proper hepatic artery and Doppler perfusion index correlates with hepatic standardized uptake value. Flow measurements of the liver may become an important parameter for selecting patients for further positron emission tomography scan and following-up the response after systemic and local therapeutic procedures.


Asunto(s)
Hemodinámica , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/metabolismo , Flujo Sanguíneo Regional , Ultrasonografía Doppler , Adulto , Anciano , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Estudios Prospectivos
2.
Genet Mol Res ; 11(4): 3824-34, 2012 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-23143934

RESUMEN

Because of its specific electrochemical properties, copper is an essential heavy metal for living organisms. As with other heavy metals, high levels can provoke damage. We examined gene expression under copper stress in wild-type fission yeast (Schizosaccharomyces pombe) through differential display. After the EC(50) concentration of CuSO(4) was determined as 50 µM, total RNA was isolated from cells treated or not with copper. The expression level of SPCC1682.13, ppk1, SPBC2F12.05c, and adg2 genes increased significantly under copper stress. Considering the functions of these genes are related to the cell cycle, cell division and chromosome dynamics, we hypothesize that retardation of the cell cycle under copper stress is relevant to the events that depend on the functions of these genes.


Asunto(s)
Puntos de Control del Ciclo Celular/efectos de los fármacos , Cobre/toxicidad , Huso Acromático/efectos de los fármacos , Huso Acromático/metabolismo , Estrés Fisiológico/efectos de los fármacos , Secuencia de Bases , Puntos de Control del Ciclo Celular/genética , Sulfato de Cobre/toxicidad , ADN Complementario/genética , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Genes Fúngicos/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Schizosaccharomyces/citología , Schizosaccharomyces/efectos de los fármacos , Schizosaccharomyces/genética , Análisis de Secuencia de ADN , Estrés Fisiológico/genética
3.
Biotech Histochem ; 97(2): 79-89, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33641543

RESUMEN

Multipotent mesenchymal stromal cells (MSC) can be isolated from many tissues, including bone marrow (BM) and placenta (PL). Human placenta can be obtained readily without invasive procedures. There may be differences, however, in differentiation capacity and immunomodulation by MSC isolated from BM or PL. The early pregnancy factor (heat shock protein 10; EPF/Hsp10) is a small protein that exhibits immunomodulatory properties. We compared BM- and PL-MSC, and assessed their efficacy for suppressing T-cell proliferation in vitro and the role of EPF/Hsp10 in this process. PL-MSC were collected from whole placenta after removal of the amniotic and chorionic membranes followed by serial enzymatic digestions. The PL-MSC were compared to BM-MSC, obtained from healthy donors. Differentiation capacity, cytokine secretion, expression and secretion of immunomodulatory molecules, immunophenotype and real time proliferation were assessed using cytokine arrays, ELISA assays, flow cytometry, immunohistochemical staining and western blotting. Whereas BM-MSC consisted of a homogeneous cell population with strong expression of mesenchymal markers, PL-MSC consisted of a mixed population of cells with variable CD73, CD90 and CD105 expression. PL-MSC exhibited a significantly greater proliferation rate than BM-MSC. The presence of both stem cells and more mature cells in the PL-MSC cultures resulted in decreased differentiation capacity and reduced efficacy of immune suppression in co-cultures with T-cells. Although robust intracellular expression of EPF/Hsp10 in both BM- and PL-MSC was observed, secretion of the protein in response to immune activating stimuli remained below detectable levels. Secretion of pro-inflammatory cytokines was significantly greater in BM-MSC than PL-MSC, whereas no difference was observed in the secretion of hematopoiesis supporting growth factors. Development of culture methods for isolation of pure populations of PL-MSC may improve the quality of the product and reproducibility of results.


Asunto(s)
Médula Ósea , Células Madre Mesenquimatosas , Células de la Médula Ósea , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Femenino , Humanos , Placenta , Embarazo , Reproducibilidad de los Resultados
4.
Mol Biol Rep ; 38(4): 2633-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21104028

RESUMEN

Vitamin D receptor (VDR) gene variants may play a key role in the susceptibility to tuberculosis (TB). We have investigated the association BsmI, TaqI, FokI polymorphisms in the VDR gene with susceptibility to tuberculosis. This study included 128 patients with TB (pulmonary and extrapulmonary TB) and 80 healthy subjects living in Istanbul, Turkey. Genetic polymorphisms were studied by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques at genomic DNA isolated from whole blood-EDTA. The present study results indicate that the genotype and allele frequencies for patient group (BB:22, Bb:53, bb:25; B allele:48%, b allele:52%) was significantly different from the control group (BB:6, Bb:48, bb: 46; B allele:30 b allele:70) due to an overrepresentation of B allele (P: 0.000 OR: 1.61 95% 1.23-2.11). However there were no significant differences in distribution of allele/genotype frequencies of FokI, TaqI variants between TB and healthy controls. This study results suggest that BsmI variant of VDR gene may play an important role in susceptibility to tuberculosis.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Polimorfismo Genético , Receptores de Calcitriol/genética , Tuberculosis/genética , Adulto , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Turquía
5.
Bull Entomol Res ; 101(3): 325-31, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21208507

RESUMEN

Effects of host species, stage and size on clutch size and sex ratio of the gregarious, idiobiont ectoparasitoid Dibrachys boarmiae were investigated at 25±2°C and 70±5% relative humidity. The greater wax moth, Galleria mellonella, small wax moth, Achroia grisella, and early stage solitary larvae of the endoparasitoid, Apanteles galleriae, were used as hosts. Clutch size was greatest from prepupae of the largest host, Galleria mellonella, with a mean of 40.07 offspring per host versus 14.73 and 2.93 for Achroia grisella and Apanteles galleriae, respectively. The mean clutch size from pupae was lower than from prepupae, being 17.27, 10.73 and 2.89 for Galleria mellonella, Achroia grisella and Apanteles galleriae, respectively. Within each host species and stage, heavier hosts resulted in larger clutches. The sex ratio of offspring (proportion of male) was approximately 0.20, with only minor differences among host species, stages and sizes.


Asunto(s)
Tamaño de la Nidada/fisiología , Mariposas Nocturnas/parasitología , Razón de Masculinidad , Avispas/fisiología , Animales , Tamaño Corporal/fisiología , Femenino , Interacciones Huésped-Parásitos , Masculino , Mariposas Nocturnas/fisiología , Estadísticas no Paramétricas
6.
Cell Biochem Funct ; 28(4): 274-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20517890

RESUMEN

Systemic sclerosis (SSc) is an autoimmune disease characterized by inflammation and fibrosis of the skin and visceral organs. Fibrosis associated with SSc is characterized by an increased synthesis of a wide range of extracellular matrix (ECM). TGF-beta is a pluripotent cytokine in a wide range of cell types. In particular it has been found to be a potent inducer of ECM protein synthesis and fibroblast migration. The TGF-beta1 gene is highly polymorphic and two signal sequence polymorphisms at codon 10 and codon 25 are linked to disease outcomes. In this study, we analysed two polymorphic sites of the TGF-beta1 gene, codon 10 and codon 25, in 43 Turkish SSc female patients with interstitial lung involvement and in 75 healty individuals by ARMS-PCR. In our study no significant difference was found in codon 10, codon 25 genotype frequencies between patient with SSc and the control group (p = 0.676, 0.375, respectively). Our findings suggest that codon 10 and 25 polymorphism cannot be related with SSc for Turkish population.


Asunto(s)
Polimorfismo de Nucleótido Simple , Esclerodermia Sistémica/genética , Factor de Crecimiento Transformador beta1/genética , Adulto , Alelos , Codón , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Persona de Mediana Edad , Esclerodermia Sistémica/etnología , Turquía
7.
Int J Immunogenet ; 36(1): 15-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19055603

RESUMEN

NRAMP1 gene has multiple pleiotropic effects on macrophage activation pathways. These pleiotropic effects may increase resistance to infections such as tuberculosis (TB), but may also lead to susceptibility of autoimmune diseases such as rheumatoid arthritis (RA). It has been hypothesized that allele 3 would be associated with autoimmune diseases, whereas allele 2 would be associated with infectious diseases, and genetic factors that enhanced survival in the epidemics of TB might have led to susceptibility for the development of RA. We analysed four NRAMP1 gene polymorphisms including 5' promoter (GT)(n) (rs34448891), INT4 (469 + 14G/C) (rs3731865), 3'UTR (1729 + 55del4) (rs17235416) and D543N (codon 543, Asp to Asn) (rs17235409) in 112 patients with TB, 98 patients with RA, 80 healthy controls for TB and 122 healthy controls for RA using ARMS-PCR and PCR-RFLP. We found a significant association between INT4 and RA (P = 0.004, odds ratio: 2.06, 95% CI: 1.24-3.41), but no significant differences between 5' promoter, D543N, 3'UTR polymorphisms and RA. There were no associations between NRAMP1 gene polymorphisms and TB. Similarly, no significant differences were observed between NRAMP1 polymorphisms and rheumatoid factor positivity and erosive disease in RA and localization of TB. INT4 polymorphism may be associated with RA in Turkish patients.


Asunto(s)
Artritis Reumatoide/genética , Enfermedades Autoinmunes/genética , Proteínas de Transporte de Catión/genética , Frecuencia de los Genes/genética , Tuberculosis/genética , Adulto , Alelos , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Factores de Riesgo
8.
J Saudi Heart Assoc ; 30(2): 75-85, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29910577

RESUMEN

OBJECTIVE: F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has been increasingly used in myocardial viability imaging. In routine PET viability studies, oral glucose and intravenous insulin loading is commonly utilized. In an optimal study, glucose and insulin loading is expected to cause FDG uptake both in hibernating and normal myocardium. However, in routine studies it is not uncommon to see absent or reduced FDG uptake in normal myocardium. In this retrospective study we further analyzed our PET viability images to evaluate FDG uptake status in myocardium under the oral glucose and intravenous insulin loading protocol that we use in our hospital. METHODS: Patients who had both myocardial perfusion single photon emission computed tomography (SPECT) and FDG PET cardiac viability studies were selected for analysis. FDG uptake status in normal and abnormal myocardial segments on perfusion SPECT was evaluated. Based on SPECT and PET findings, patients were divided into two main groups and four subgroups. Group 1 included PET viable studies and Group 2 included PET-nonviable studies. Subgroups based on FDG uptake in normal myocardium were 1a and 2a (normal uptake) and 1b and 2b (absent or significantly reduced uptake). RESULTS: Seventy-one patients met the inclusion criteria. Forty-two patients were PET-viable and 29 were PET-nonviable. In 33 of 71 patients (46.4%) there was absent or significantly reduced FDG uptake in one or more normal myocardial segments, which was identified more in PET-viable than PET-nonviable patients (59.5% vs. 27.5%, p = 0.008). This finding was also more frequent in diabetic than nondiabetic patients (53% vs. 31.8%), but the difference was not significant (p = 0.160). CONCLUSIONS: In nearly half of our patients, one or more normal myocardial segments showed absent or significantly reduced FDG uptake. This finding, particularly if it is diffuse, could be from suboptimal study, inadequacy of current glucose and insulin loading protocols, or various other patient-related causes affecting FDG uptake both in the normal and hibernating myocardium. In cases with significantly reduced FDG uptake in normal myocardium, PET images should be interpreted cautiously to prevent false-negative results for viability.

9.
Rev Esp Med Nucl Imagen Mol ; 35(2): 118-20, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26522002

RESUMEN

The (18)F-FDG PET/CT scan has been suggested for whole-body imaging to identify ectopic adrenocorticotrophic hormone secreting tumours, but there are some challenges involved. The case of a patient is presented, who was admitted with the pre-diagnosis of ectopic ACTH syndrome. On the CT, a nodular lesion was detected in the medial segment of the right lung. The FDG uptake of the lesion seemed to be increased visually, but was not pathological quantitatively (SUVmax: 1.8) on the PET/CT. There was also diffuse increased uptake (SUVmax: 14.2) in the enlarged adrenal glands. The lesion was reported as a possible malignant lesion with low FDG affinity, such as a low grade neuroendocrine tumour, while the diffuse enlarged adrenal glands with high uptake were interpreted as diffusely hyperplasic, due to Cushing's syndrome. The patient was treated with a surgical wedge resection. The histopathological diagnosis confirmed that the tumour was a grade 1 well-differentiated neuroendocrine carcinoma.


Asunto(s)
Síndrome de ACTH Ectópico/diagnóstico por imagen , Carcinoma Neuroendocrino/diagnóstico por imagen , Síndrome de Cushing/complicaciones , Neoplasias Pulmonares/diagnóstico por imagen , Síndrome de ACTH Ectópico/etiología , Carcinoma Neuroendocrino/metabolismo , Síndrome de Cushing/diagnóstico , Femenino , Fluorodesoxiglucosa F18 , Humanos , Hidrocortisona/sangre , Neoplasias Pulmonares/metabolismo , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos
10.
Hippokratia ; 19(2): 176-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27418769

RESUMEN

BACKGROUND: Bardet-Biedl syndrome is a rare disorder characterized by retinal dystrophy, obesity, kidney dysfunction, polydactyly, hypogonadism and cognitive impairment. It can be accompanied by systemic findings such as malignancy, hypertension, diabetes mellitus, constitutional and functional disorders of urogenital system and liver fibrosis. CASE REPORT: A 35-year-old woman with Bardet-Biedl syndrome was referred to our outpatient nephrology clinic with dysuria, acute renal failure, and urinary tract infection. A sized 2 x 1 cm mass between labia major and minor was noted, while CT scan showed a lesion that encompassed uterus and extended to the posterior side of the bladder in the left adnexal region and a 3 cm lesion in the liver. Excisional biopsy of the mass revealed a well-differentiated, squamous cell carcinoma. Dysuria resolved with insertion of urinary catheter after bougie dilatation and the patient was referred for radiotherapy. CONCLUSION: It should be kept in the mind that renal failure may develop due to constitutional urogenital anomalies such as vulva carcinoma. This can be an important cause of morbidity and mortality in patients with Bardet-Biedl syndrome.Hippokratia 2015; 19 (2):176-178.

11.
Semin Nucl Med ; 31(1): 3-16, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11200204

RESUMEN

Single photon emission computed tomography (SPECT) of the bone is the second most frequently performed SPECT examination in routine nuclear medicine practice, with cardiac SPECT being the most frequent. Compared with planar scintigraphy, SPECT increases image contrast and improves lesion detection and localization. Studies have documented the unique diagnostic information provided by SPECT, particularly for avascular necrosis of the femoral head, in patients with back pain, for the differential diagnosis between malignant and benign spinal lesions, in the detection of metastatic cancer in the spine, for the diagnosis of temporomandibular joint internal derangement, and for the evaluation of acute and chronic knee pain. Although less rigorously documented, SPECT is being increasingly used in all types of situations that demand more precise anatomic localization of abnormal tracer uptake. The effectiveness of bone SPECT increases with the selection of the proper collimator, which allows one to acquire adequate counts and minimize the patient-to-detector distance. Low-energy, ultrahigh-resolution or high-resolution collimation is preferred over all-purpose collimators. Multihead gamma cameras can increase the counts obtained or shorten acquisition time, making SPECT acquisitions more practical in busy departments and also increasing image quality compared with single-head cameras. Iterative reconstruction, with the use of ordered subsets estimation maximization, provides better quality images than classical filtered back projection algorithms. Three-dimensional image analysis often aids lesion localization.


Asunto(s)
Huesos/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Dolor de Espalda/diagnóstico por imagen , Neoplasias Óseas/diagnóstico por imagen , Articulación de la Cadera/diagnóstico por imagen , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Osteoartritis/diagnóstico por imagen , Osteomielitis/diagnóstico por imagen , Cráneo/diagnóstico por imagen , Columna Vertebral/diagnóstico por imagen , Espondilólisis/diagnóstico por imagen , Tecnología Radiológica , Articulación Cigapofisaria/diagnóstico por imagen
12.
Biotechnol Prog ; 17(3): 474-80, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11386868

RESUMEN

In this paper, we show that dilute maleic acid, a dicarboxylic acid, hydrolyzes cellobiose, the repeat unit of cellulose, and the microcrystalline cellulose Avicel as effectively as dilute sulfuric acid but with minimal glucose degradation. Maleic acid, superior to other carboxylic acids reported in this paper, gives higher yields of glucose that is more easily fermented as a result of lower concentrations of degradation products. These results are especially significant because maleic acid, in the form of maleic anhydride, is widely available and produced in large quantities annually.


Asunto(s)
Biotecnología/métodos , Celulosa/metabolismo , Ácidos Dicarboxílicos/química , Ácido Acético/química , Ácido Acético/metabolismo , Celobiosa/química , Celobiosa/metabolismo , Celulosa/química , Ácidos Dicarboxílicos/metabolismo , Glucosa/metabolismo , Hidrólisis , Cinética , Maleatos/química , Maleatos/metabolismo , Ácido Succínico/química , Ácido Succínico/metabolismo , Ácidos Sulfúricos/química , Ácidos Sulfúricos/metabolismo
13.
Brain Dev ; 21(3): 179-83, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10372904

RESUMEN

The aim of the present study was to correlate between clinical parameters (age, age of onset, frequency and duration of seizures) and semiquantitative interictal SPECT parameters in children with partial seizures. We obtained 30 patients who had hypoperfusion in interictal SPECT, retrospectively. All patients underwent a detailed clinical examination, electroencephalography (EEG) investigation and brain computerized tomography (CT) and/or magnetic resonance imaging (MRI). Single photon emission computerized tomography (SPECT) studies were evaluated visually and by calculating semiquantitative parameters (the degree (asymmetry index, AI) and extent (number of ROI) of hypoperfusion). Visual analysis detected ipsilateral hypoperfusion in 23 (76%) patients with a unilateral focus and contralateral hypoperfusion in seven patients. We found an inverse correlation between the age at onset of seizure (r = -0.40, P = 0.025), frequency of seizures(but positive correlation; r = 0.77, P = 0.000) and AI. Number of ROIs showed a moderate correlation with the frequency of seizures (r = 0.67, P = 0.000), while correlation of the age at onset of seizures was not significant. This study performed in pediatric patients also suggested that either SPECT parameters may be used for correlating with clinical parameters.


Asunto(s)
Encéfalo/diagnóstico por imagen , Epilepsias Parciales/diagnóstico por imagen , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único , Adolescente , Factores de Edad , Edad de Inicio , Circulación Cerebrovascular , Niño , Preescolar , Electroencefalografía , Epilepsias Parciales/fisiopatología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Radiofármacos , Lóbulo Temporal/diagnóstico por imagen , Tomografía Computarizada por Rayos X
14.
Nucl Med Commun ; 25(1): 29-37, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15061262

RESUMEN

It has been suggested that low back pain (LBP) may arise from lumbosacral transitional vertebral articulation (LSTVA) itself. It is known that bone scintigraphy is a valuable tool for the recognition of pain arising from bone and articular diseases. Therefore we aimed to show planar and SPECT bone scintigraphic findings of LSTVA and compare them with the LBP and X-ray findings. Twenty-eight patients (aged 20-63 years) in whom LSTVA had been identified radiographically were evaluated with planar bone scintigraphy, utilizing 99mTc methylene diphosphonate; and single photon emission computed tomography (SPECT) bone scintigraphy. Eighteen patients had LBP whereas 10 had not. There were 25 type IIA, one type IIB and two type IIIA LSTV articulation. On planar images, normal or non-focal minimally increased uptake superimposed on the upper sacroiliac joint was seen in patients without degenerative changes regardless of LBP whereas SPECT showed non-focal mild increased uptake on the area medial to the upper sacroiliac joint. Planar scans showed normal to non-focal mild, and mild-to-moderately increased uptake whereas SPECT demonstrated focal mild-to-moderately and markedly increased uptake in patients with degenerative changes without LBP and with LBP, respectively. The X-ray results showed an association of LBP degenerative changes, and the SPECT results showed a focal, markedly increased, uptake. We conclude that this focal, markedly increased, uptake may show the metabolically active degenerative changes of LSTV articulation and may help to reveal the pain arising from LSTVA. Therefore we propose that bone scintigraphy may be considered for the evaluation of patients with LBP thought to arise from LSTV articulation.


Asunto(s)
Dolor de la Región Lumbar/diagnóstico por imagen , Vértebras Lumbares/anomalías , Vértebras Lumbares/diagnóstico por imagen , Sacro/anomalías , Sacro/diagnóstico por imagen , Medronato de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Femenino , Humanos , Dolor de la Región Lumbar/etiología , Región Lumbosacra/anomalías , Región Lumbosacra/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiografía , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Nucl Med Commun ; 21(1): 83-7, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10717907

RESUMEN

It is well known that uraemia affects skeletal muscle metabolism. This has been attributed to a variety of causes, including anaemia, vitamin D, carnitine deficiency and hyperparathyroidism. The aim of this study was to ascertain whether 99Tcm-sestamibi leg scintigraphy is useful in the evaluation of skeletal muscle metabolism and the monitoring of treatment response in uraemic myopathy. Forty patients with chronic renal failure and 24 normal controls underwent examination. Fifteen patients with chronic renal failure received erythropoietin treatment. 99Tcm-sestamibi leg scintigraphy was performed in all subjects and in 15 patients after therapy. The calf-to-ankle uptake ratio was calculated by semi-quantitative analysis and normalized to lean body mass. The normalized uptake ratios were significantly different between patients and controls. After erythropoietin therapy, there was a significant increase in the normalized uptake ratios compared with pre-therapy. Our results suggest that 99Tcm-sestamibi leg scintigraphy is useful in the assessment of muscle metabolic abnormalities and the effect of treatment in uraemic myopathy.


Asunto(s)
Eritropoyetina/uso terapéutico , Fallo Renal Crónico/diagnóstico por imagen , Fallo Renal Crónico/tratamiento farmacológico , Pierna/diagnóstico por imagen , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Radiofármacos , Tecnecio Tc 99m Sestamibi , Adulto , Anciano , Proteínas Sanguíneas/metabolismo , Femenino , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Proteínas Recombinantes , Ultrasonografía
16.
Nucl Med Commun ; 22(1): 39-44, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11233550

RESUMEN

Although several hypotheses have been suggested regarding the accumulation of 99Tc(m)-sestamibi in tumours, the exact uptake mechanism is still a matter of discussion. We investigated ultrastructural cell type of thyroid tumours by electron microscopy (EM) and compared them with uptake of 99Tc(m)-sestamibi. Thyroid scintigraphy with 99Tc(m)-sestamibi was performed on 25 patients who displayed a cold nodule on previous pertechnetate scintigraphy. Tumour-to-thyroid (T/N) uptake ratio was measured semiquantitatively. Surgery was performed in all patients and cytological evaluations were done by EM. Histopathology revealed six papillary carcinomas, 16 follicular adenomas and three Hurthle cell tumours. Thyroid cells were classified as A and B cells using EM. The cytoplasm of an A cell has the normal amount of mitochondria, whereas cytoplasm of a B cell (mitochondria-rich oxyphilic cell) contains abundant mitochondria. The median T/N ratio on the early scan for an A-cell tumour was 1.21 (range, 0.74-3.2), late T/N ratio was 1.25 (range, 0.72-3.85). The T/N ratio for the B-cell tumours was 1.42 (range, 0.6-3.6) on the early scan and 1.18 (range, 0.64-5.58) on the late scan. There was no statistically significant difference between T/N ratios of A- and B-cell tumour groups. A significant difference was also not seen between early and late T/N ratios. According to our findings, 99Tc(m)-sestamibi accumulates in thyroid tumours with both A and B cells, therefore these results suggest that the mitochondrial content of tumours is not only responsible for sestamibi uptake and retention.


Asunto(s)
Radiofármacos/farmacocinética , Tecnecio Tc 99m Sestamibi/farmacocinética , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Adenoma/patología , Adulto , Biopsia , Carcinoma Papilar/patología , Femenino , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Neoplasias de la Tiroides/ultraestructura
17.
Enzyme Microb Technol ; 14: 609-13, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11540167

RESUMEN

Soybeans contain the enzyme alpha-galactosidase, which hydrolyzes alpha-1, 6 linkages in stachyose and raffinose to give sucrose and galactose. We have found that galactose, a competitive product inhibitor of alpha-galactosidase, strongly promotes the heat stability of the tetrameric form of the enzyme at pH 4.0 and at temperatures of up to 70 degrees C for 60 min. Stachyose and raffinose also protect alpha-galactosidase from denaturation at pH 4.0 although to a lesser extent. Glucose and mannose have little effect. At pH 7.0 the enzyme is a monomer, and galactose has no effect on the heat stability of the enzyme. In the absence of heat protection of the enzyme by added sugars, a series deactivation mechanism was found to describe the deactivation data. In comparison, a unimolecular, non-first order deactivation model applies at pH 4.0, where heat protection effects were observed. At a temperature above 60 degrees C, simple deactivation is a suitable model. The results suggest that alpha-galactosidase conformation and heat stability are directly related.


Asunto(s)
Glycine max/enzimología , Calor , Proteínas de Plantas/aislamiento & purificación , alfa-Galactosidasa/aislamiento & purificación , alfa-Galactosidasa/metabolismo , Estabilidad de Enzimas , Galactosa/biosíntesis , Concentración de Iones de Hidrógeno , Hidrólisis , Modelos Biológicos , Oligosacáridos/metabolismo , Proteínas de Plantas/metabolismo , Rafinosa/metabolismo , Sacarosa/metabolismo
18.
Ann Nucl Med ; 15(4): 397-401, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11577769

RESUMEN

OBJECTIVES: Neuromuscular electrical stimulation (NMES) is widely used for improving muscle strength by simultaneous contraction in the prevention of muscle atrophy. Although there exist many clinical methods for evaluating the therapeutic response of muscles, 99mTc-sestamibi which is a skeletal muscle perfusion and metabolism agent has not previously been used for this purpose. The aim of our work was to ascertain whether 99Tc-sestamibi muscle scintigraphy is useful in the monitoring of therapeutic response to NMES in healthy women. METHODS: The study included 16 women aged between 21 and 45, with a mean age of 32.7 +/- 6.4. Both quadriceps femoris muscles (QFM) of each patient were studied. After randomization to remove the effect of the dominant side, one QFM of each patient was subjected to the NMES procedure for a period of 20 days. NMES was performed with an alternating biphasic rectangular current, from a computed electrical stimulator daily for 23 minutes. After measurement of skinfold thickness over the thigh, pre- and post-NMES girth measurements were assessed in centimeters. Sixty minutes after injections of 555 MBq 99mTc-sestamibi, static images of the thigh were obtained for 5 minutes. The thigh-to-knee uptake ratio was calculated by semiquantitative analysis and normalized to body surface area (NUR = normalized uptake ratio). RESULTS: The difference between the pre and post NMES NUR values was significant (1.76 +/- 0.31 versus 2.25 +/- 0.38, p = 0.0000). The percentage (%) increase in NUR values also well correlated with the % increase in thigh girth measurements (r = 0.89, p = 0.0000). CONCLUSION: These results indicated that 99mTc-sestamibi muscle scintigraphy as a new tool may be useful in evaluating therapeutic response to NMES.


Asunto(s)
Terapia por Estimulación Eléctrica , Músculo Esquelético/diagnóstico por imagen , Radiofármacos , Tecnecio Tc 99m Sestamibi , Adulto , Femenino , Humanos , Persona de Mediana Edad , Contracción Muscular , Músculo Esquelético/fisiología , Atrofia Muscular/prevención & control , Cintigrafía
19.
Appl Biochem Biotechnol ; 62(2-3): 131-49, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9170251

RESUMEN

A large amount of inedible plant material, generated as a result of plant growth in a Controlled Ecological Life Support System (CELSS), should be pretreated and converted into forms that can be recycled on earth as well as in space. The main portion of the inedible biomass is lignocellulosic material. Enzymatic hydrolysis of this cellulose would provide sugars for many other uses by recycling carbon, hydrogen, oxygen, and nitrogen through formation of carbon dioxide, heat, and sugars, which are potential foodstuffs. To obtain monosaccharides from cellulose, the protective effect of lignin should be removed. White-rot fungi degrade lignin more extensively and rapidly than other microorganisms. Pleurotus ostreatus degrades lignin effectively, and produces edible and flavorful mushrooms that increase the quality and nutritional value of the diet. This mushroom is also capable of metabolizing hemicellulose, thereby providing a food use of this pentose containing polysaccharide. This study presents the current knowledge of physiology and biochemistry of primary and secondary metabolisms of basidiomycetes, and degradation mechanism of lignin. A better understanding of the ligninolytic activity of white-rot fungi will impact the CELSS Program by providing insights on how edible fungi might be used to recycle the inedible portions of the crops.


Asunto(s)
Sistemas Ecológicos Cerrados , Lignina/metabolismo , Plantas/metabolismo , Biomasa , Carbono/metabolismo , Hidrólisis , Nitrógeno/metabolismo , Polyporaceae/fisiología
20.
Appl Biochem Biotechnol ; 82(1): 1-15, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15304774

RESUMEN

Solid-state fermentation (SSF) of inedible parts of rapeseed was carried out using a white-rot fungus, Pleurotus ostreatus, to degrade lignocellulosic material for mycelial-single cell protein (SCP) production. This SSF system has the potential to be adapted to a controlled ecological life support system in space travel owing to the lack of storage space. The system for converting lignocellulosic material to SCP by P. ostreatus is simple; it can be carried out in a compact reactor. The fungal vegetative growth was better with a particle size of plant material ranging from 0.42 to 10 mm, whereas lignin degradation of the lignocellulose was the highest with particle sizes ranging from 0.42 to 0.84 mm. The addition of veratryl alcohol (3,4-dimethoxybenzyl alcohol), hydrogen peroxide, and glycerol promotes lignocellulose degradation by P. ostreatus. The enhancement of bioconversion was also observed when a gas-flow bioreactor was used to supply oxygen and to maintain the constant moisture of the reactor. With this reactor, approx 85% of the material was converted to fungal and other types of biomass after 60 d of incubation.

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