RESUMEN
Recent studies have shown that the tumor extracellular matrix (ECM) associates with immunosuppression, and that targeting the ECM can improve immune infiltration and responsiveness to immunotherapy. A question that remains unresolved is whether the ECM directly educates the immune phenotypes seen in tumors. Here, we identify a tumor-associated macrophage (TAM) population associated with poor prognosis, interruption of the cancer immunity cycle, and tumor ECM composition. To investigate whether the ECM was capable of generating this TAM phenotype, we developed a decellularized tissue model that retains the native ECM architecture and composition. Macrophages cultured on decellularized ovarian metastasis shared transcriptional profiles with the TAMs found in human tissue. ECM-educated macrophages have a tissue-remodeling and immunoregulatory phenotype, inducing altered T cell marker expression and proliferation. We conclude that the tumor ECM directly educates this macrophage population found in cancer tissues. Therefore, current and emerging cancer therapies that target the tumor ECM may be tailored to improve macrophage phenotype and their downstream regulation of immunity.
Asunto(s)
Macrófagos , Neoplasias Ováricas , Humanos , Femenino , Macrófagos/metabolismo , Matriz Extracelular/metabolismo , Neoplasias Ováricas/patología , Fenotipo , Microambiente TumoralRESUMEN
BACKGROUND: We assessed the capacity of epidermal growth factor receptor (EGFR)-targeted immunoliposomes to deliver cargo to brain tumor tissue in patients with relapsed glioblastoma harboring an EGFR amplification. We aimed to assess the tolerability and effectiveness of anti-EGFR immunoliposomes loaded with doxorubicin (anti-EGFR ILs-dox) in glioblastoma multiforme patients. PATIENTS AND METHODS: Patients with EGFR-amplified, relapsed glioblastoma were included in this phase I pharmacokinetic trial. Patients received up to four cycles of anti-EGFR ILs-dox. Twenty-four hours later, plasma and cerebrospinal fluid (CSF) samples were obtained. In addition, we also treated three patients with anti-EGFR ILs-dox before resection of their relapsed glioblastoma. Doxorubicin concentrations were measured in plasma, CSF, and tumor tissue. Safety and efficacy parameters were also obtained. RESULTS: There were no or negligible levels of doxorubicin found in the CSF demonstrating that anti-EGFR ILs-dox are not able to cross the blood-brain barrier (BBB). However, significant levels were detected in glioblastoma tissue 24 h after the application, indicating that the disruption of BBB integrity present in high-grade gliomas might enable liposome delivery into tumor tissue. No new safety issues were observed. The median progression-free survival was 1.5 months and the median overall survival was 8 months. One patient undergoing surgery had a very long remission suggesting that neoadjuvant administration may have a positive effect on outcome. CONCLUSIONS: We clearly demonstrate that anti-EGFR-immunoliposomes can be targeted to EGFR-amplified glioblastoma and cargo-in this case doxorubicin-can be delivered, although these immunoliposomes do not cross the intact BBB. (The GBM-LIPO trial was registered as NCT03603379).
Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/tratamiento farmacológico , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapéutico , Receptores ErbB , Glioblastoma/tratamiento farmacológico , Humanos , LiposomasRESUMEN
The Oriental fruit fly, Bactrocera dorsalis sensu stricto, is one of the most economically destructive pests of fruits and vegetables especially in East Asia. Based on its phytophagous life style, this species dispersed with the diffusion and implementation of agriculture, while globalization allowed it to establish adventive populations in different tropical and subtropical areas of the world. We used nine SSR loci over twelve samples collected across East Asia, i.e. an area that, in relatively few years, has become a theatre of intensive agriculture and a lively fruit trade. Our aim is to disentangle the different forces that have affected the invasion pattern and shaped the genetic make-up of populations of this fruit fly. Our data suggest that the considered samples probably represent well established populations in terms of genetic variability and population structuring. The human influence on the genetic shape of populations and diffusion is evident, but factors such as breeding/habitat size and life history traits of the species may have determined the post introduction phases and expansion. In East Asia the origin of diffusion can most probably be allocated in the oriental coastal provinces of China, from where this fruit fly spread into Southeast Asia. The spread of this species deserves attention for the development and implementation of risk assessment and control measures.
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Variación Genética , Repeticiones de Microsatélite , Selección Genética , Tephritidae/genética , Distribución Animal , Animales , Ecosistema , Asia Oriental , Control de Insectos , Filogeografía , Población/genéticaRESUMEN
Asthma is a common respiratory disease affecting â¼300 million people worldwide. Airway inflammation is thought to contribute to asthma pathogenesis, but the direct relationship between inflammation and airway hyperresponsiveness (AHR) remains unclear. This study investigates the role of inflammation in a steroid-insensitive, severe allergic airway disease model and in severe asthmatics stratified by inflammatory profile. First, we used the T-helper (T(H))-17 cells adoptive transfer mouse model of asthma to induce pulmonary inflammation, which was lessened by tumor necrosis factor (TNF)-α neutralization or neutrophil depletion. Although decreased airspace inflammation following TNFα neutralization and neutrophil depletion rescued lung compliance, neither intervention improved AHR to methacholine, and tissue inflammation remained elevated when compared with control. Further, sputum samples were collected and analyzed from 41 severe asthmatics. In severe asthmatics with elevated levels of sputum neutrophils, but low levels of eosinophils, increased inflammatory markers did not correlate with worsened lung function. This subset of asthmatics also had significantly higher levels of T(H)17-related cytokines in their sputum compared with severe asthmatics with other inflammatory phenotypes. Overall, this work suggests that lung compliance may be linked with cellular inflammation in the airspace, whereas T-cell-driven AHR may be associated with tissue inflammation and other pulmonary factors.
Asunto(s)
Asma/complicaciones , Inflamación/complicaciones , Pulmón/fisiología , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Animales , Asma/inmunología , Asma/fisiopatología , Hiperreactividad Bronquial/inmunología , Broncoconstrictores/farmacología , Niño , Citocinas/inmunología , Femenino , Humanos , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Cloruro de Metacolina/farmacología , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Esputo/inmunologíaRESUMEN
BACKGROUND: Several classical risk factors are at the base of vascular calcifications in hemodialysis patients. Among these, according to a general opinion, also bone turnover plays a role, which, however, requires a better definition. In addition, it has been suggested that there is a relationship between primary osteoporosis and vascular calcifications. This bone biopsy-based study on a hemodialysis patient cohort is a contribution to the evaluation of these alleged relations. METHODS: This study has been carried out on a cohort of 32 patients on maintenance hemodialysis, who were subjected to transiliac bone biopsy for histomorphometric, histodynamic and bone aluminum deposit evaluation. The patients were also examined with multislice computerized tomography for quantitation of heart and coronary calcifications. RESULTS: The patients were affected by renal osteodystrophy with a wide range of bone formation rate values. A significant negative correlation was found between the rate of bone turnover and log-transformed cardiac calcification score (p < 0.003). There were also negative significant correlations between the cardiac and coronary calcification score log and trabecular number (p < 0.02 and p < 0.05, respectively), while the correlations were positive with trabecular separation (p < 0.03 and p < 0.05, respectively). However, multiregression analysis, forward method, selected only age, hemodialysis age and serum Ca as predictive variables of cardiac and coronary calcification score log, while the histomorphometric and histodynamic variables were excluded. CONCLUSIONS: In this study, in spite of the suggestive findings of the univariate statistical approach, a further multivariate analysis was indicative of a spurious association between calcification scores and both bone turnover and histomorphometric parameters of trabecular mass and connectivity. Bone turnover and trabecular mass do not appear to be prominently connected with the extent of cardiac and coronary calcifications in hemodialysis patients.
Asunto(s)
Remodelación Ósea , Calcinosis/diagnóstico por imagen , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico por imagen , Diálisis Renal , Adulto , Factores de Edad , Anciano , Calcinosis/etiología , Calcio/sangre , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/complicaciones , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/patología , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/etiología , Vasos Coronarios/patología , Femenino , Humanos , Ilion/patología , Masculino , Persona de Mediana Edad , Miocardio/patología , Osteoporosis/etiología , Osteoporosis/patología , Tomografía Computarizada por Rayos X , Uremia/complicaciones , Uremia/diagnóstico por imagen , Uremia/patologíaRESUMEN
AIM: Cardiac disease is a major cause of mortality in uremic patients. The aim of this paper was to evaluate cardiac calcium content in uremic patients with multislice computed tomography (MSCT). METHODS: The study has been carried out on 120 uremic and 28 nonuremic patients affected by cardiovascular disease. Serum calcium, phosphorus, calcium-phosphate product, intact PTH were assayed. Several lipidic and nutritional parameters were measured. Calcification values obtained with the MSCT were reported in terms of Agatson scores. RESULTS: We found that the average score values in cohort on uremic was 10 times higher than in nonuremic patients (score values 3.389 vs 328). Cardiac calcification score was found to be correlated significantly to age (P=0.006), HD age (P=0.010), serum calcium (P=0.006), iPTH (P=0.004). Multiregression analysis (MRA) with the cardiac score as dependent variable selected the following variables (R(2) 0.612): age (P=0.002), HD age (P=0.010), serum cholesterol (P<0.000), triglycerides (P=0.001) and inversely HDL cholesterol (P=0.001) and non-HDL cholesterol (P=0.001) as predictive variables for cardiac score. By comparing patients with scores lower and higher than 400, the group with score <400 showed a significantly lower age (P=0.0001), HD vintage (P=0.01) and a significantly higher serum cholesterol (P=0.009), HDL cholesterol (P=0.05) and non-HDL cholesterol (P=0.05). CONCLUSIONS: The MSCT could help in identifying and stratifying high-risk patients to implement preventive strategies. The control of mineral metabolism and of lipid levels is important in prevention of arterial calcification in uremic patients.
Asunto(s)
Calcinosis/diagnóstico por imagen , Calcinosis/etiología , Cardiopatías/diagnóstico por imagen , Cardiopatías/etiología , Fallo Renal Crónico/terapia , Diálisis Renal/efectos adversos , Tomografía Computarizada Espiral , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Chronic kidney disease, with special regard to hemodialysis patients, develop frequent and widespread cardiac and vascular calcifications. In the heart calcifications are mainly located in the coronary arteries and in the valvular structures. There is a strict relation between cardiovascular mortality in CKD and the extent of cardiac and vascular calcifications. Therefore it is important to evaluate the causes of extraskeletal calcifications for the evaluation of the possibility of prevention. The importance of hyperphosphatemia, of hypercalcemia and of the increased CAxP product as a cause of cardiac calcification has been clearly underlined. However the mechanism of calcification, initially considered a physico-chemical precipitation, has been investigated with the conclusion that the process is mediated by cellular differentiation and production of factors favoring mineralization in the extracellular milieu. Increased serum phosphate levels are able to induce a transformation of vascular smooth muscle cells into osteoblast-like cells, able to produce factors known to be pro-mineralizing agents in the bone tissue. Further studies have revealed the importance of a number of inhibitors of calcification of cardiovascular structures, like Fetuin-A, MGP, Osteopontin, Osteoprotegerin. Therefore at present the calcification process of vascular tissue is considered to be linked to a balance between inducers and inhibitors of calcium-phosphate deposits. Prevention of cardiac calcifications is at present mainly based of optimal control of serum phosphate and reduction of calcium load through the use of non-calcium containing phosphate binders. Treatment with statins for prevention and treatment of atherosclerosis is also an important means of decreasing the size and number of atherosclerotic plaques, where a portion of the calcification process develops.
Asunto(s)
Calcinosis/etiología , Calcinosis/prevención & control , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Fallo Renal Crónico/complicaciones , HumanosRESUMEN
AIM: The aim of this study is cardiac calcium content evaluation in hemodialysis patients by a new technique, based on ultrafast multisection CT (MTC). METHODS: The study was carried out on 30 HD patients, 14 F and 16 M, average age 57.7 +/- 13.9 years, average HD age 57.3 +/- 47.4 months. The intact PTH levels were 625.4 +/- 571 pg/mL. Serum calcium, phosphate and CaxP product were 9.75 +/- 0.84 mg/mL, 6.21 +/- 1.01 mg/dL and 60.2 +/- 10.7 mg2/dL2, respectively. RESULTS: The values obtained with the MTC technique were reported in terms of Agatson scores. Score values frankly in the pathologic range (>100) were found in 24 patients (80%). Correlation analysis has shown positive and significant correlation coefficients of the score with patients' age (p = 0.003), serum calcium (p = 0.012), CaxP (p = 0.015), iPTH (p = 0.049), and borderline, to HD age (p = 0. 06). CONCLUSION: Risk factors for cardiac calcification are mainly age, degree of hyperparathyroidism, increased CaxP and serum calcium levels. A control of calcium phosphate parameters in hemodialysis patients seems to be mandatory to avoid increased severity of coronary artery disease.
Asunto(s)
Calcinosis/diagnóstico por imagen , Cardiomiopatías/diagnóstico por imagen , Fallo Renal Crónico/diagnóstico por imagen , Diálisis Renal , Adulto , Anciano , Calcinosis/etiología , Cardiomiopatías/etiología , Estudios de Cohortes , Vasos Coronarios/patología , Femenino , Válvulas Cardíacas/diagnóstico por imagen , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Tomografía Computarizada EspiralRESUMEN
To evaluate the long-term results of parathyroidectomy (PTX) on parathyroid function, blood pressure and anemia, data of 45 patients with secondary Hyperparathyroidism in dialysis who had undergone PTX were collected retrospectively from 8 different dialysis units. The patients, 25 M and 20 F, mean age 56 +/- 11 years, who were followed up for an average period of 3.3 +/- 2.3 years, were divided into four groups according to the surgical procedure: 19 patients had had a subtotal PTX; 10 patients had undergone total PTX with autotransplantation (AT); 10 patients had had total PTX without AT, and 6 patients had undergone partial PTX. Taking a reduction in intact PTH > 50% as sign of successful PTX, only 5 patients did not attain this result. Considering values of PTH between 20 and 200 pg/ml at the mid-term observation (1-2 years) as the optimal result, values under 20 pg/ml as an expression of permanent hypoparathyroidism, and those above 200 pg/ml as indicating persistent/recurrent hyperparathyroidism, 65.5% of patients operated with subtotal PTX and total PTX + AT had a therapeutic success, versus 31.2% of patients in the other two groups, due to excess permanent hypoparathyroidism and persistent/recurrent hyperparathyroidism; 20 of 45 patients with preoperative hypertension experienced a statistically and clinically significant decrease in blood pressure levels. An increase in serum hemoglobin was also observed, despite a reduction of administered erythropoietin. In conclusion, the results of PTX obtained from this multicenter study are comparable to those reported by single leading centers. Recommended surgical procedures are subtotal PTX and total PTX with AT. The fall in blood pressure in hypertensive patients is clinically significant, and improvement in anemia is also observed with a reduction in erythropoietin dosage.
Asunto(s)
Anemia/prevención & control , Presión Sanguínea/fisiología , Hiperparatiroidismo Secundario/cirugía , Fallo Renal Crónico/complicaciones , Glándulas Paratiroides/fisiopatología , Paratiroidectomía , Diálisis Renal/efectos adversos , Anciano , Anemia/sangre , Femenino , Hemoglobinas/metabolismo , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Estudios RetrospectivosRESUMEN
A case of an uncommon sphenoidal metastasis from prostate carcinoma with cranial nerve involvement is described. Current concepts of metastatic spread of this tumor to the skull base, clinical signs and therapeutic approaches are reviewed in the light of the available literature.
Asunto(s)
Adenocarcinoma/secundario , Neoplasias de los Nervios Craneales/secundario , Neoplasias de la Próstata/patología , Seno Esfenoidal/patología , Adenocarcinoma/patología , Medios de Contraste , Neoplasias de los Nervios Craneales/patología , Gadolinio DTPA , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: The urinary excretion of deoxypyridinoline (DPD) was evaluated in predialysis chronic renal failure (CRF), together with intact PTH and several classic markers of bone turnover in order to assess whether urine free and total DPD excretion are equivalent parameters of bone turnover in CRF, and to evaluate the relationship between urine DPD excretion, PTH and the other bone markers. METHODS: The study was carried out in 94 patients with different degrees of renal failure due to various kidney diseases. Besides urinary DPD expressed as free DPD, total DPD, free/total DPD, free DPD/Cr and total DPD/Cr, the following determinations were made: intact PTH, bone alkaline phosphatase (BALP), total alkaline phosphatase (AP), osteocalcin (BGP), serum C-terminal telopeptide of collagen type I (ICTP) and hydroxyproline (OHpro). The patients were divided into 3 groups according to the increasing severity of renal failure (Ccr >40, 40-20, <20 ml/min). RESULTS: The ratio free/total DPD decreased (NS) with advancing renal failure, and was inversely correlated with total DPD excretion. While PTH increased progressively to about four times the values observed in the Ccr >40 group, there was a parallel increase only in BGP and ICTP, parameters retained in the serum with decreasing renal function, while AP, BALP, total DPD and OHpro did not change. However, significant correlations between total DPD/Cr and PTH, BALP, BGP and ICTP were also found. CONCLUSIONS: In CRF free DPD is an unreliable index of bone turnover due to a probable interference in its production from the peptide-bound DPD. Total DPD or total DPD/Cr are better used. In spite of the significant correlations observed in advanced renal failure between PTH and most of the parameters examined, a resistance of bone tissue to PTH action in CRF must be considered.
Asunto(s)
Aminoácidos/orina , Remodelación Ósea , Fallo Renal Crónico/fisiopatología , Anciano , Fosfatasa Alcalina/metabolismo , Biomarcadores/sangre , Biomarcadores/orina , Huesos/enzimología , Colágeno , Colágeno Tipo I , Creatinina/sangre , Creatinina/orina , Femenino , Humanos , Hidroxiprolina/orina , Fallo Renal Crónico/sangre , Fallo Renal Crónico/orina , Masculino , Persona de Mediana Edad , Osteocalcina/sangre , Hormona Paratiroidea/sangre , PéptidosRESUMEN
BACKGROUND: Metastatic spread of tumors to the skull is quite unusual and often represents a relevant diagnostic and therapeutic problem. Skull involvement can be observed in various neoplasms of epithelial origin (rarely in other tumors) and most often responsible are lung, breast, thyroid, kidney and prostate cancers. Less frequent than multiple involvement, single cranial vault lesions are often amenable to surgical resection instead of radiotherapy alone; scope of this paper is to highlight the key points of the management of such entities, including a brief review of the pathological and radiological features of these entities. METHODS: A retrospective study has enabled us to select from our files ten cases of surgically treated solitary cranial vault metastases, with a variable follow-up ranging from 6 months to 4 years. In all the cases the operation consisted in a monobloc resection and a cranioplasty for the repair of the defect. RESULTS: We have observed no perioperative morbidity or mortality; in all the cases surgery allowed histologic confirmation and immediate relief of neurological symptoms and cosmetic impairment (when present). CONCLUSIONS: Monobloc resection of solitary cranial vault metastatic lesions is an easy made and safe procedure, to be performed in every patient except the ones in poor general conditions, which are better addressed to radiotherapy alone.
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Neoplasias Craneales/secundario , Neoplasias Craneales/cirugía , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Craneales/diagnóstico , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Administration of a single dose of 1,25-OH(2)D(3) can lower PTH levels for up to 4 days in chronic hemodialysis patients. Our purpose was to verify the effects of the same weekly dose of calcitriol per os given in one, two or three administrations, to patients on dialysis with secondary hyperparathyroidism. Thirty patients were studied, divided in to three groups each of 10 patients. Calcitriol therapy in group A was given as a single weekly dose of 0.08 microg/kg b.w. In group B the same total weekly dose was divided in two equal doses. In group C the same total weekly dose was divided in three times. Treatment lasted 2 months. After 8 weeks of therapy the fall in intact PTH was statistically significant in each group, respectively with one-way ANOVA: p<0.02 (A); p<0.002 (B); p<0.001 (c). Two-way ANOVA for comparison of PTH % variation among the three groups was statistically significant p<0.003. Significance was due to difference between group A and groups B and C. The present study confirms the efficacy of single dose in suppressing significantly intact PTH. However, when the same weekly dose is divided into two or in three time-spaced administrations, the suppressive effects are definitely increased.
Asunto(s)
Calcitriol/administración & dosificación , Agonistas de los Canales de Calcio/administración & dosificación , Diálisis Renal/métodos , Administración Oral , Adulto , Anciano , Fosfatasa Alcalina/sangre , Fosfatasa Alcalina/efectos de los fármacos , Análisis de Varianza , Depresión Química , Femenino , Humanos , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/tratamiento farmacológico , Hiperparatiroidismo Secundario/etiología , Fallo Renal Crónico/sangre , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Diálisis Renal/estadística & datos numéricos , Factores de TiempoRESUMEN
BACKGROUND: Fifty per cent of patients with chronic hepatitis C, show detectable cryoglobulinaemia, even though most of them do not show cryoglobulinaemia related symptoms. Peripheral neuropathy is present in most of the patients with symptomatic cryoglobulinaemia, where it may be the first clinical manifestation. The prevalence of peripheral neuropathy in patients with hepatitis C and cryoglobulinaemia is unknown. AIMS: To assess the prevalence of peripheral neuropathy in HCV infected patients with symptomatic or asymptomatic detectable cryoglobulinaemia. PATIENTS AND METHODS: Eighty-nine patients with HCV infection and detectable cryoglobulinaemia underwent electrophysiological studies. RESULTS: Electrophysiological evidence of peripheral neuropathy was found in 37% and was significantly associated with: the presence of cryoglobulinaemia syndrome, older age, higher rheumatoid factor reactivity and immunoglobulin M levels and reduced complement C4 activity. However, electrophysiological evidence of peripheral neuropathy was unrelated to cryocrit levels and type of cryoglobulinaemia and was found in 23/68 patients without any symptoms of cryoglobulinaemia other than pain and paresthesia. CONCLUSIONS: These findings suggest that peripheral neuropathy is frequent in patients with hepatitis C and detectable cryoglobulins. Neuropathy was found to be present in 1/3 of patients without other cryoglobulinaemia-related symptoms, thus a direct or indirect role of HCV, independent of cryoglobulinaemia, in the pathogenesis of nerve damage cannot be ruled out.
Asunto(s)
Crioglobulinemia/complicaciones , Hepatitis C/complicaciones , Enfermedades del Sistema Nervioso Periférico/etiología , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Factores de Edad , Distribución de Chi-Cuadrado , Complemento C4/análisis , Electrofisiología , Femenino , Humanos , Inmunoglobulinas/análisis , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso Periférico/epidemiología , Prevalencia , Estudios Prospectivos , Factor Reumatoide/análisis , Estadísticas no ParamétricasRESUMEN
BACKGROUND: Renal osteodystrophy includes a number of low and high turnover bone histologic patterns which require a bone biopsy for their full identification. The role of intact PTH and several classical and more recent bone markers in the non-invasive diagnosis of renal bone disease in patients with CRF in HD requires further definition since available published data are limited. METHODS: In addition to intact PTH, alkaline phosphatase (AP) and osteocalcin (BGP), bone alkaline phosphatase isoenzyme (BALP), tartrate resistant acid phosphatase (TRAP), C-terminal cross-linked peptide of collagen type 1 (ICTP) and deoxypyridinoline (DPD) were measured in the serum of 41 patients on haemodialysis, subjected at the same time to transiliac bone biopsy for histomorphometric, histodynamic and aluminium histochemical examination. Histodynamic evaluation following double tetracycline label, was carried out in 37 patients. The patients had no evidence of active cytolytic and cholestatic liver disease and a history of very limited aluminium exposure. RESULTS: The patients had differing degrees of hyper-parathyroidism, with intact PTH ranging from normal to very elevated levels. Serum values of the markers BGP, ICTP and DPD, normally excreted through the kidneys, were on average very high. The correlation coefficients of the humoral parameters vs dynamic variables, such as BFR/BS, were high. The highest values were: intact PTH 0.798, AP 0.900, BALP 0.891, ICTP 0.807. The patients, grouped in low turnover osteodystrophy (LTO; 9), mixed osteodystrophy (MO; 9) and prevalent hyperparathyroidism (HP; 23), showed significant difference in the levels of most humoral and static and dynamic parameters (ANOVA). Bone aluminium histochemistry was negative in all cases. Discrimination of LTO patients from the other groups by humoral parameters, at the highest value of accuracy, showed 100% sensitivity and 93.7% specificity with a cut-off of 12.9 ng/ml for BALP; 88.9% sensitivity and 93.7% specificity with a cut-off of 21.5 ng/ml for DPD, and 88.9% sensitivity and 90.6% specificity with a cut-off of 79.7 pg/ml for intact PTH. The other markers had lower values. A standardized z-score approach for evaluation of all humoral parameters was also carried out. Using all variables, a correct classification of MO/HP and of LTO was possible in 93.8 and 88.9% of the cases, respectively. Predictive power was 96.8 and 80%, respectively for MO/HP and LTO. When the only variables used were intact PTH and BALP, a correct classification of MO/HP and LTO was possible in 90.6% and 88.9%, respectively. Predictive value of MO/HP was 96.7% and for LTO 72.7%. Predictive values using PTH and AP were 96.3% and 57.2%, respectively. CONCLUSION: Intact PTH and several relatively new bone markers are of certain value in the non-invasive diagnosis of renal osteodystrophy. However some of the humoral markers carry the same quality of information and the use of intact PTH and BALP may be adequate in the discrimination of bone histologic patterns. In cases exempt from liver disease, PTH and AP may be used as a less costly alternative. Bone biopsy could be chiefly limited to cases with borderline humoral values and to all those with a suspected aluminium overload.
Asunto(s)
Huesos/metabolismo , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/metabolismo , Diálisis Renal , Adulto , Fosfatasa Alcalina/sangre , Biomarcadores , Biopsia , Huesos/enzimología , Huesos/patología , Femenino , Humanos , Isoenzimas/sangre , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangreRESUMEN
The bacterial phosphotransferase system (PTS) consists of two energy-coupling soluble proteins (enzyme I and HPr) and a large number of inner membrane transporters (enzymes II) that mediate concomitant phosphorylation and translocation of sugars and hexitols. The transporters consist of three functional units (IIA, IIB, IIC), which occur either as protein subunits or domains of a multidomain polypeptide. The membrane-spanning IIC domain contains the substrate binding site; IIA and IIB are phosphorylation domains that transfer phosphate from HPr to the transported sugar. The transporter complexes of the PTS are good examples for variation of design by modular assembly of domains and subunits. The domain order is IIC-IIB in the membrane subunit of the Escherichia coli glucose transporter (IICBGlc) and IIB-IIC in Salmonella typhimurium sucrose transporter (IIBCScr). The phosphorylation domain of IICBGlc was translocated from the carboxyl-terminal to the amino-terminal end of the IIC domain, and the activity of the circularly permuted form was optimized by variation of the length and the composition of the interdomain linker. IIBapCGlc with an alanine-proline-rich interdomain linker has 70% of the control specific activity after purification and reconstitution into proteoliposomes. These results indicate that the amino-terminal end of IICBGlc must be on the cytoplasmic side of the inner membrane, that membrane insertion of the IIC domain is insensitive to the modification of its amino-terminal end, and that a domain swap as it could occur by a single DNA translocation event can rapidly lead to a functional protein. However, IIB could not be substituted for by glucokinase. Fusion proteins between the IIC domain and glucokinase do not transport and phosphorylate glucose in an ATP-dependent mechanism, although the IIC moiety displays transport activity upon complementation with soluble subclonal IIB, and the glucokinase moiety retains ATP-dependent nonvectorial kinase activity. This indicates that IIC and IIB are two cooperative units and not only sequentially acting upon a common substrate, and that translocation of glucose must be conformationally coupled to the phosphorylation/dephosphorylation cycle of IIB.