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1.
Dig Liver Dis ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39237429

RESUMO

BACKGROUND: The challenge of transplant waiting-lists is to provide organs for all candidates while maintaining efficiency and equity. AIMS: We investigated the probability of being transplanted or of waiting-list dropout in Italy. METHODS: Data from 12,749 adult patients waitlisted for primary liver-transplantation from January 2012 to December 2022 were collected from the National Transplant-Registry.The cohort was divided into Eras:1 (2012-2014);2 (2015-2018);and 3 (2019-2022). RESULTS: The one-year probability of undergoing transplant increased (67.6 % in Era 1vs73.8 % in Era 3,p < 0001) with a complementary 46 % decrease in waiting-list failures. Patients with hepatocellular-carcinoma were transplanted more often than cirrhotics[at model for end-stage liver-disease (MELD)-15:HR = 1.28,95 %CI:1.21-1.35;at MELD-25:HR = 1.04,95 %CI:0.92-1.19) and those with other indications (at MELD-15:HR = 1.27,95 %CI:1.11-1.46) across all eras. Candidates with Hepatitis-B-virus (HBV)related disease had a greater probability of transplant than those with Hepatitis-C virus-related (HR = 1.13,95 %CI:1.07-1.20), alcohol-related (HR = 1.13,95 %CI:1.05-1.21), and metabolic-related (HR = 1.18,95 %CI:1.09-1.28)disease. Waiting-list failures increased by 27 % every 5 MELD-points and by 14 % for every 5-year increase in recipient-age and decreased by 10 % with each 10-cm increase in stature. Blood-group O patients showed the highest probability of waiting-list failure (HR = 1.28,95 %CI:1.15-1.43). CONCLUSIONS: Liver-transplantation waiting-list success-rates have significantly improved in Italy, with patients with hepatocellular-carcinoma and/or HBV-related diseases being favored. High MELD-score, old-age, short-stature, and blood-group O were significant risk-factors for waiting-list failure. Efforts to improve organ-allocation and prioritization-policies are underway.

2.
Sci Rep ; 13(1): 18610, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903872

RESUMO

Fructosyl peptide oxidases (FPOX) are deglycating enzymes that find application as key enzymatic components in diabetes monitoring devices. Indeed, their use with blood samples can provide a measurement of the concentration of glycated hemoglobin and glycated albumin, two well-known diabetes markers. However, the FPOX currently employed in enzymatic assays cannot directly detect whole glycated proteins, making it necessary to perform a preliminary proteolytic treatment of the target protein to generate small glycated peptides that can act as viable substrates for the enzyme. This is a costly and time consuming step. In this work, we used an in silico protein engineering approach to enhance the overall thermal stability of the enzyme and to improve its catalytic activity toward large substrates. The final design shows a marked improvement in thermal stability relative to the wild type enzyme, a distinct widening of its access tunnel and significant enzymatic activity towards a range of glycated substrates.


Assuntos
Diabetes Mellitus , Peptídeos , Humanos , Engenharia de Proteínas , Peptídeo Hidrolases , Albumina Sérica
3.
Eur J Clin Invest ; 53(5): e13954, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36645727

RESUMO

BACKGROUND AND AIM: Notwithstanding the improvement in therapies, patients affected by thalassemia major (TM) and intermedia (TI) are still at high risk of cardiac complications. This study aimed at evaluating the incidence and predictive factors for developing cardiac events in adult ß-TM and TI patients. POPULATION AND METHODS: Data on diagnosis and clinical history were collected retrospectively; prospective data on new-onset cardiac failure and arrhythmias, echocardiographic parameters, biochemical variables including non-transferrin-bound iron (NTBI) and labile plasma iron (LPI), magnetic resonance imaging (MRI) T2* measurement of hepatic and cardiac iron deposits, and iron chelation therapy were recorded during a 6-year follow-up. RESULTS: Thirty-seven patients, 29 TM and 8 TI, were included. At baseline, 8 TM patients and 1 TI patient had previously experienced a cardiac event (mainly heart failure). All patients were on chelation therapy and only 3 TM patients had mild-to-severe cardiac siderosis. During follow-up, 11 patients (29.7%) experienced a new cardiac event. The occurrence of cardiac events was correlated to high LPI levels (OR 12.0, 95% CI 1.56-92.3, p .017), low mean pre-transfusion haemoglobin (OR 0.21, 95% C.I. 0.051-0.761, p .21) and echocardiographic parameters suggestive of myocardial hypertrophy. Multivariate analysis disclosed high LPI and left ventricle mass index (LVMI) as independent variables significantly associated with cardiac events. Cardiac iron deposits measured by MRI T2* failed to predict cardiac events. CONCLUSION: LPI, Hb levels and echocardiographic parameters assessing cardiac remodelling are associated with cardiac events in adult TM and TI patients. LPI might represent both a prognostic marker and a potential target for novel treatment strategies. Further studies are warranted to confirm our findings on larger populations.


Assuntos
Cardiopatias , Sobrecarga de Ferro , Talassemia beta , Adulto , Humanos , Ferro/uso terapêutico , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/tratamento farmacológico , Estudos Prospectivos , Estudos Retrospectivos , Talassemia beta/complicações , Talassemia beta/terapia , Ecocardiografia
4.
Metabolites ; 12(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36144223

RESUMO

Given its remarkable property to easily switch between different oxidative states, iron is essential in countless cellular functions which involve redox reactions. At the same time, uncontrolled interactions between iron and its surrounding milieu may be damaging to cells and tissues. Heme-the iron-chelated form of protoporphyrin IX-is a macrocyclic tetrapyrrole and a coordination complex for diatomic gases, accurately engineered by evolution to exploit the catalytic, oxygen-binding, and oxidoreductive properties of iron while minimizing its damaging effects on tissues. The majority of the body production of heme is ultimately incorporated into hemoglobin within mature erythrocytes; thus, regulation of heme biosynthesis by iron is central in erythropoiesis. Additionally, heme is a cofactor in several metabolic pathways, which can be modulated by iron-dependent signals as well. Impairment in some steps of the pathway of heme biosynthesis is the main pathogenetic mechanism of two groups of diseases collectively known as porphyrias and congenital sideroblastic anemias. In porphyrias, according to the specific enzyme involved, heme precursors accumulate up to the enzyme stop in disease-specific patterns and organs. Therefore, different porphyrias manifest themselves under strikingly different clinical pictures. In congenital sideroblastic anemias, instead, an altered utilization of mitochondrial iron by erythroid precursors leads to mitochondrial iron overload and an accumulation of ring sideroblasts in the bone marrow. In line with the complexity of the processes involved, the role of iron in these conditions is then multifarious. This review aims to summarise the most important lines of evidence concerning the interplay between iron and heme metabolism, as well as the clinical and experimental aspects of the role of iron in inherited conditions of altered heme biosynthesis.

5.
Dig Liver Dis ; 54(12): 1664-1671, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096992

RESUMO

BACKGROUND: Over the last decades relevant epidemiological changes of liver diseases have occurred, together with greatly improved treatment opportunities. AIM: To investigate how the indications for elective adult liver transplantation and the underlying disease etiologies have evolved in Italy. METHODS: We recruited from the National Transplant Registry a cohort comprising 17,317 adults patients waitlisted for primary liver transplantation from January-2004 to December-2020. Patients were divided into three Eras:1(2004-2011),2(2012-2014) and 3(2015-2020). RESULTS: Waitlistings for cirrhosis decreased from 65.9% in Era 1 to 46.1% in Era 3, while those for HCC increased from 28.7% to 48.7%. Comparing Eras 1 and 3, waitlistings for HCV-related cirrhosis decreased from 35.9% to 12.1%, yet those for HCV-related HCC increased from 8.5% to 26.7%. Waitlistings for HBV-related cirrhosis remained almost unchanged (13.2% and 12.4%), while those for HBV-related HCC increased from 4.0% to 11.6%. ALD-related cirrhosis decreased from 16.9% to 12.9% while ALD-related HCC increased from 1.9% to 3.9%. CONCLUSIONS: A sharp increase in liver transplant waitlisting for HCC and a concomitant decrease of waitlisting for cirrhosis have occurred In Italy. Despite HCV infection has noticeably decreased, still remains the primary etiology of waitlisting for HCC, while ALD and HBV represent the main causes for cirrhosis.


Assuntos
Carcinoma Hepatocelular , Hepatite C , Neoplasias Hepáticas , Transplante de Fígado , Adulto , Humanos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Cirrose Hepática/epidemiologia , Cirrose Hepática/cirurgia , Sistema de Registros , Hepatite C/complicações , Hepatite C/epidemiologia
6.
PLoS One ; 15(4): e0231725, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348352

RESUMO

BACKGROUND: The future burden of non-communicable diseases (NCDs) depends on numerous factors such as population ageing, evolution of societal trends, behavioural and physiological risk factors of individuals (e.g. smoking, alcohol use, obesity, physical inactivity, and hypertension). This study aims to assess the burden of NCDs in Europe by 2050 under alternative scenarios. METHODS: This study combines qualitative and quantitative forecasting techniques to examine how population health in Europe may evolve from 2015 to 2050, taking into account future societal trends. Four scenarios were developed (one business-as-usual scenario, two response scenarios and one pessimistic scenario) and assessed against 'best' and 'worst'-case scenarios. This study provides quantitative estimates of both diseases and mortality outcomes, using a microsimulation model incorporating international survey data. FINDINGS: Each scenario is associated with a different risk factor prevalence rate across Europe during the period 2015-2050. The prevalence and incidence of NCDs consistently increase during the analysed time period, mainly driven by population ageing. In more optimistic scenarios, diseases will appear in later ages, while in the pessimistic scenarios, NCDs will impair working-age people. Life expectancy is expected to grow in all scenarios, but with differences by up to 4 years across scenarios and population groups. Premature mortality from NCDs will be reduced in more optimistic scenarios but stagnate in the worst-case scenario. INTERPRETATION: Population ageing will have a greater impact on the spread of NCDs by 2050 compared to risk factors. Nevertheless, risk factors, which are influenced by living environments, are an important factor for determining future life expectancy in Europe.


Assuntos
Previsões , Carga Global da Doença/tendências , Modelos Estatísticos , Mortalidade Prematura/tendências , Doenças não Transmissíveis/epidemiologia , Dinâmica Populacional/tendências , Idoso , Idoso de 80 Anos ou mais , Simulação por Computador , Europa (Continente)/epidemiologia , Feminino , Humanos , Expectativa de Vida/tendências , Masculino , Pessoa de Meia-Idade , Doenças não Transmissíveis/prevenção & controle , Fatores de Risco
7.
Phytother Res ; 28(3): 444-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23775598

RESUMO

A proprietary lecithin delivery system of curcumin (Meriva) was evaluated in a controlled study to assess its efficacy in alleviating the side effects of cancer chemo- and radiotherapy in 160 patients undergoing these treatments. In both cases, a semi-quantitative evaluation of the side effects was carried out using a visual analogue scale, assessing also the plasma free radical status in all patients. Results showed that lecithinized curcumin might alleviate the burden of side effects associated to chemo- and radiotherapy, suggesting that the anecdotal use of various preparations of curcumin as a supportive agent for cancer treatment is well worth a systematic investigation in larger scale clinical trials. The capacity of curcumin to upregulate anti-oxidative responses and downregulate inflammatory pathways could explain its beneficial effect in tempering the prolonged and systemic oxidative and inflammatory effects of cancer treatment, and the beneficial effects observed in the plasma oxidative status in all patients of the treatment group support this view.


Assuntos
Antineoplásicos/efeitos adversos , Curcumina/administração & dosagem , Lecitinas/administração & dosagem , Neoplasias/tratamento farmacológico , Radioterapia/efeitos adversos , Adulto , Idoso , Curcumina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/radioterapia , Medição da Dor
8.
Int J Artif Organs ; 36(5): 335-40, 2013 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-23504812

RESUMO

INTRODUCTION: Evaluation of kidney transplant candidates is based on strict exclusion of major pathologies, such as neoplastic disease. The aim of this study is to evaluate epidemiological and clinical impact of tumor disease in an Italian renal transplant waiting list and to propose a screening schedule for neoplastic detection.
 MATERIALS AND METHODS: We retrospectively observed data of patients enrolled on the Emilia-Romagna kidney transplant waiting list between 1st August 2008 and 31st December 2010, evaluating the different causes of getting out from the list, the histologic type and incidence of cancer and the correlation between cancer onset and clinical features. The ratio of observed to expected cancer numbers (standardized incidence ratio, SIR), was estimated. RESULTS: We observed 2345 patients; 1297 got out from the waiting list; 57 of them (4,4%) got out because the onset of tumor. The overall incidence rate of cancer was 1354.8 (x 100,000 person-year) (1045.9 person-year in patients awaiting for first transplant(FT), 1851.5 person-year in patients awaiting for second transplant(ST)). The overall prevalence of cancer was 2,43% (2.2% in FT, 3.4% in ST) with a SIR of 1.8; In our population the prevalence of cancers related to ESKD was 52.6% with a SIR of 15.8.
 CONCLUSION: Kidney transplant waiting list patients present a higher incidence and prevalence of cancer compared to general population; it could be important to evaluate them for ESKD related malignancies because of their high incidence.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim , Neoplasias/epidemiologia , Listas de Espera , Adolescente , Adulto , Idoso , Feminino , Humanos , Incidência , Itália/epidemiologia , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Prevalência , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
9.
Mol Biosyst ; 7(5): 1773-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21431179

RESUMO

This work concerns the synthesis, the supramolecular assembly and the evaluation of some biological properties, such as DNA and RNA-binding ability and human serum stability, of novel nucleopeptides. These compounds are of potential interest for the well-known properties that similar compounds, such as natural peptidyl nucleosides, possess in biology and medicine and also for the possibility to realize nucleopeptide-based supramolecular systems useful for drug and gene delivery applications. More particularly, all four nucleobase-containing peptides were synthesized by solid phase synthesis, purified by HPLC and characterized by NMR and ESI-MS. Subsequently, nucleopeptide self-assembly as well as DNA and RNA-binding ability were investigated by CD spectroscopy and further information on the formation of molecular networks, based on the peptidyl nucleoside analogues and nucleic acids, was obtained by Laser Light Scattering. Finally, nucleopeptide enzymatic stability was studied and a half life of about 2 hours was found in the presence of 50% fresh human serum.


Assuntos
Modelos Químicos , Nucleosídeos/química , Ácidos Nucleicos Peptídicos/síntese química , Peptídeos/química , Adenina/química , Ligação Competitiva , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Citosina/química , DNA/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácidos Nucleicos Peptídicos/química , Ácidos Nucleicos Peptídicos/metabolismo , RNA/metabolismo , Soro/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Timina/química
10.
J Ocul Pharmacol Ther ; 25(6): 537-40, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19916788

RESUMO

PURPOSE: The growing numbers of diabetes cases in the developed world are followed by increasing numbers of people diagnosed with diabetic complications. Diabetic microangiopathies in the eye lead to the development of retinopathy involving gradual loss of vision. Previous studies with Pycnogenol showed effectiveness for stopping progression of preproliferative stages of retinopathy. The aim of our study was to show protective effects of Pycnogenol in early stages of retinopathy, characterized by mild to moderate retinal edema in the absence of hemorrhages or hard exudates in the macula center. METHODS: Following treatment with Pycnogenol (24 patients) for 3 months, retinal edema score (dilated ophthalmology) and retinal thickness (high resolution ultrasound) showed statistically significant improvement as compared to the placebo group (22 patients), which showed negligible changes to baseline. Laser Doppler flow velocity measurements at the central retinal artery showed a statistically significant increase from 34 to 44 cm/s in the Pycnogenol group as compared to marginal effects in the control group. RESULTS: The major positive observation of this study is the visual improvement, which was subjectively perceived by 18 out of 24 patients in the Pycnogenol group. Testing of visual acuity using the Snellen chart showed a significant improvement from baseline 14/20 to 17/20 already, after 2 months treatment, whereas no change was found in the control group. CONCLUSIONS: Pycnogenol taken at this early stage of retinopathy may enhance retinal blood circulation accompanied by regression of edema, which favorably improves vision of patients.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Flavonoides/uso terapêutico , Edema Macular/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Retinopatia Diabética/fisiopatologia , Método Duplo-Cego , Feminino , Flavonoides/farmacologia , Humanos , Fluxometria por Laser-Doppler , Edema Macular/etiologia , Masculino , Microcirculação/efeitos dos fármacos , Pessoa de Meia-Idade , Extratos Vegetais , Inibidores da Agregação Plaquetária/farmacologia , Fatores de Tempo , Resultado do Tratamento , Acuidade Visual/efeitos dos fármacos
11.
J Endourol ; 22(7): 1509-17, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18613779

RESUMO

PURPOSE: To evaluate the tolerability and safety of a newly designed probe for trans-perineal microwave thermoablation (TPMT) of the prostate in patients with benign prostatic hyperplasia (BPH), and the in vivo microwave effects on prostatic tissue. PATIENTS AND METHODS: Nine patients with obstructive BPH who were candidates for open prostatectomy were selected for this study. Under local anesthesia and transrectal ultrasound monitoring, all patients underwent a single standardized application of TPMT. The visual analog scale (VAS) and Short Form-36 health survey (SF-36) questionnaire were administered to each patient prior to, during, and 1 month after TPMT in order to evaluate pain and quality of life. Then the International Index of Erectile Function (IIEF-5) and International Prostate Symptom Score (IPSS) questionnaires were administered to each patient at baseline and 1 month after prostatectomy in order to evaluate sexual and urinary function, respectively. Then all patients were divided into three groups and underwent open prostatectomy 7, 15, and 30 days after TPMT, respectively. The prostatic adenomas were then evaluated by a pathologist. RESULTS: No adverse events from TPMT treatment were noted. In particular, no patients reported local, pelvic, or abdominal pain during the procedure or subsequent alterations of defecation rhythm, ano-rectal/intestinal problems, or hematuria. No differences in quality of life or in sexual function were reported. The diameters of the lesions obtained with TPMT treatment ranged from 16 to 18.1 mm in all patients. Quasi-spheroid lesions with a well-defined area of complete coagulative necrosis were documented in all removed adenomas 7, 15, and 30 days after TMPT. CONCLUSIONS: The AMICA-PROBE is a safe, well-tolerated, and repeatable method to treat BPH with microwave thermotherapy. The spheroid lesions obtained demonstrated the maximal control over the radial and longitudinal coagulative effects of the therapy. Phase II studies are needed to further evaluate the efficacy of this new probe.


Assuntos
Micro-Ondas , Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/instrumentação , Idoso , Humanos , Masculino , Medição da Dor , Hiperplasia Prostática/diagnóstico por imagem , Hiperplasia Prostática/patologia , Inquéritos e Questionários , Ressecção Transuretral da Próstata/efeitos adversos , Ultrassonografia
12.
Angiology ; 59(1): 77-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18319226

RESUMO

Lymphedema is mainly characterized by swelling, fibrosis, and non-pitting edema. The aim of this study was evaluation of the long-term (10 years) effects of autologous lymphatic tissue implant in lymphedema. Lymphatic tissue from 9 patients (harvested form the same patient in areas not affected by lymphedema) was reimplanted into the affected limb, and these patients were followed for 10 years. Lymph nodes were harvested at the neck, axillary, or inguinal space (contralateral limb). Results showed that limb volume was decreased in the treatment group vs. controls. In ultrasound, black, low density, lymphatic spaces were visible in 100% of patients at inclusion but in only 23% of these subjects at 10 years. Thus, this early report proposes a new, minimally invasive method to improve lymphedema. Studies in progress will indicate the role of lymphatic transplant in the management of lymphedema and the best indications for this method.


Assuntos
Linfedema/cirurgia , Tecido Linfoide/transplante , Adulto , Índice de Massa Corporal , Líquido Extracelular/metabolismo , Feminino , Seguimentos , Custos de Cuidados de Saúde , Humanos , Linfedema/diagnóstico por imagem , Linfedema/etiologia , Linfedema/metabolismo , Linfedema/patologia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Cooperação do Paciente , Projetos Piloto , Proteínas/metabolismo , Índice de Gravidade de Doença , Pele/patologia , Fatores de Tempo , Transplante Autólogo/efeitos adversos , Transplante Autólogo/economia , Resultado do Tratamento , Ultrassonografia
13.
J Chromatogr A ; 1143(1-2): 36-40, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17239898

RESUMO

A novel microwave method has been applied to the hydrothermal extraction of essential oil from plants. An insulated microwave coaxial antenna was introduced inside a 1000 ml glass flask containing dry Laurus nobilis L. leaves and tap water. Microwave power up to 800 W at 2450 MHz was emitted in continuous wave regime (CW) or in pulsed regime (PR) at 8 kW peak power. Stirring with a magnetic bar and a Clevenger refrigerator connected to the flask enabled to complete the extraction in 1 h. The results of the in situ microwave extraction were compared with those obtained by heating the same reactor with a conventional electric mantle by gas chromatography-mass spectrometry (GC-MS) analysis. Differences were observed both in the composition of the essential oil and from the energetic point of view. The essential oil obtained with microwave (MW) methods contained substantially higher amounts of oxygenated compounds and lower amounts of monoterpenes than conventional method. The in situ microwave heating is safe and versatile; it presents time and energy saving advantages, and therefore it can be considered useful also for industrial applications.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Laurus/química , Micro-Ondas , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química
14.
Artigo em Inglês | MEDLINE | ID: mdl-17036787

RESUMO

Fast echographic multiparameter multi-image novel apparatus (FEMMINA), is a hardware and software platform dedicated to ultrasonic signal and image processing. FEMMINA is able to operate with sequences of radiofrequency (RF) frames. Its architecture is designed to be modular, expandable, and aimed at implementing different ultrasonic investigation techniques. The first experimental characteristic of this system is in its capability to operate in real time with ultrasonic RF signals, starting from acquisition up to processing, storage, and visualization. The second characteristic is the user-system interactivity that allows one to modify the operation appropriately while observing results. Currently, FEMMINA works in both typical experimental situations to study novel investigation techniques and clinical field to validate the proposed methods in different human districts.


Assuntos
Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Software , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Interface Usuário-Computador , Pesquisa Biomédica/instrumentação , Pesquisa Biomédica/métodos , Gráficos por Computador , Sistemas Computacionais , Desenho de Equipamento , Análise de Falha de Equipamento , Interpretação de Imagem Assistida por Computador/instrumentação , Armazenamento e Recuperação da Informação/métodos , Análise Numérica Assistida por Computador , Ondas de Rádio , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
15.
J Clin Endocrinol Metab ; 89(12): 6097-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15579764

RESUMO

Raloxifene (RAL), a selective estrogen receptor modulator, is indicated for the prevention and treatment of postmenopausal osteoporosis. RAL, by decreasing bone turnover, prevents bone loss and microarchitecture damage, reducing the incidence of osteoporotic fractures. Our previous in vitro data demonstrated that RAL modulates osteoclast activity by, at least in part, an IL-6- and TNF-alpha-dependent mechanism. In this study we evaluated the effects of RAL treatment (60 mg/d) on circulating levels of these cytokines in 14 postmenopausal women with osteoporosis. Lumbar bone density (determined by dual energy x-ray absorptiometry) and IL-6 and TNF-alpha levels were measured before and after 6 and 24 months of therapy. After 24 months, RAL increased bone density. IL-6 and TNF-alpha expression, elevated before treatment, significantly decreased (50% and 30%, respectively) after 6 months. This effect was sustained up to the end of the treatment (75% and 35%, respectively). Thus, our data show that RAL can modulate circulating levels of cytokines involved in osteoclastogenesis and bone resorption, suggesting that modulation of soluble factors could play a pivotal role in the mechanisms of the osteoprotective effect of RAL.


Assuntos
Interleucina-6/biossíntese , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/tratamento farmacológico , Cloridrato de Raloxifeno/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Fator de Necrose Tumoral alfa/biossíntese , Densidade Óssea/efeitos dos fármacos , Feminino , Humanos , Interleucina-6/antagonistas & inibidores , Interleucina-6/sangue , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/metabolismo , Projetos Piloto , Fatores de Tempo , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
16.
Biol Reprod ; 70(1): 168-77, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14522834

RESUMO

The platelet-derived growth factor (PDGF) family of ligands and receptors play a pivotal role in the development of various organs. The critical importance of the PDGF-mediated signaling during embryonic development and adult physiology of the kidney and the common mesonephric origin of the epididymis and kidney prompted us to investigate the immunohistochemical localization of PDGF A- and B-chain and PDGF receptor (PDGFR) alpha- and beta-subunit in rat and mouse epididymis, the expression profiles of the corresponding mRNAs, and the consequences of a loss-of-function mutation at the PDGF-A, PDGF-B, and PDGFR-beta loci on mouse epididymis phenotypic appearance. Prenatally, PDGF-A and PDGFR-alpha immunohistochemical staining was seen in both species, whereas PDGF-B and PDGFR-beta were absent. The cellular localization of PDGF-A within the epithelium and the alpha-receptor in the mesenchyme in either mouse or rat before birth suggests that the PDGF-A/PDGFR-alpha system might be involved in the epididymal epithelial-mesenchymal interaction during the fetal period of life. Postnatally, PDGF A- and B-ligand and PDGFR alpha- and beta-subunit were confined in the epithelium. The identity of PDGF and PDGFR proteins were further confirmed by immunoblotting. In line with the immunohistochemical studies, PDGF-A and PDGFR-alpha mRNAs were seen by reverse transcription-polymerase chain reaction in rat and mouse tissue before birth, whereas PDGF-B and PDGFR-beta were almost not detectable. During the first days of life, PDGF-B and PDGFR-beta genes started to appear, and the overall trend in mRNA expression throughout postnatal development showed that the transcripts levels for PDGF-A, PDGF-B, PDGFR-beta, and PDGFR-alpha were constant with the only exception of a progressive decrease of PDGFR-alpha in adult rats. The PDGF-A null mutation strongly influenced the epididymal phenotype starting from puberty; only fetal PDGF-B and PDGFR-beta -/- mice were available, and no differences were seen in the epididymis of these animals, compared with wild-type littermates. Taken together, these data indicate that the PDGF system is highly expressed in the epididymis and suggest that PDGF could be involved in the maintenance of morphological structure and functional control of this organ.


Assuntos
Epididimo/fisiologia , Fator de Crescimento Derivado de Plaquetas/genética , Proteínas Proto-Oncogênicas c-sis/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Animais , Western Blotting , Epididimo/citologia , Epididimo/crescimento & desenvolvimento , Imuno-Histoquímica , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Fenótipo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo
17.
Mol Cell Biol ; 22(12): 4011-9, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12024015

RESUMO

Transcription of the Saccharomyces cerevisiae ARG1 gene is under the control of both positive and negative elements. Activation of the gene in minimal medium is induced by Gcn4. Repression occurs in the presence of arginine and requires the ArgR/Mcm1 complex that binds to two upstream arginine control (ARC) elements. With the recent finding that the E2 ubiquitin conjugase Rad6 modifies histone H2B, we examined the role of Rad6 in the regulation of ARG1 transcription. We find that Rad6 is required for repression of ARG1 in rich medium, with expression increased approximately 10-fold in a rad6 null background. Chromatin immunoprecipitation analysis indicates increased binding of TATA-binding protein in the absence of Rad6. The active-site cysteine of Rad6 is required for repression, implicating ubiquitination in the process. The effects of Rad6 at ARG1 involve two components. In one of these, histone H2B is the likely target for ubiquitination by Rad6, since a strain expressing histone H2B with the principal ubiquitination site converted from lysine to arginine shows a fivefold relief of repression. The second component requires Ubr1 and thus likely the pathway of N-end rule degradation. Through the analysis of promoter constructs with ARC deleted and an arg80 rad6 double mutant, we show that Rad6 repression is mediated through the ArgR/Mcm1 complex. In addition, analysis of an ada2 rad6 deletion strain indicated that the SAGA acetyltransferase complex and Rad6 act in the same pathway to repress ARG1 in rich medium.


Assuntos
Argininossuccinato Sintase/genética , Proteínas de Ligação a DNA , Ligases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool) , Proteínas de Saccharomyces cerevisiae/genética , Transcrição Gênica , Ubiquitina-Proteína Ligases , Arginina , Argininossuccinato Sintase/metabolismo , Sequência de Bases , Meios de Cultura , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Ligases/genética , Proteína 1 de Manutenção de Minicromossomo/genética , Proteína 1 de Manutenção de Minicromossomo/metabolismo , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Enzimas de Conjugação de Ubiquitina , Leveduras/genética , Leveduras/metabolismo
18.
J Biol Chem ; 277(17): 15171-81, 2002 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-11821430

RESUMO

Post-translational modifications of histones play an important role in modulating gene transcription within chromatin. We used the mouse mammary tumor virus (MMTV) promoter, which adopts an ordered nucleosomal structure, to investigate the impact of a specific inhibitor of histone deacetylase, trichostatin A (TSA), on progesterone receptor-activated transcription. TSA induced global histone hyperacetylation, and this effect occurred independently of the presence of hormone. Interestingly, chromatin immunoprecipitation analysis revealed no significant change in the level of acetylated histones associated with the MMTV promoter following high TSA treatment. In human breast cancer cells, in which the MMTV promoter adopts a constitutively "open" chromatin structure, treatment with TSA converted the MMTV promoter into a closed structure. Addition of hormone did not overcome this TSA-induced closure of the promoter chromatin. Furthermore, TSA treatment resulted in the eviction of the transcription factor nuclear factor-1 from the promoter and reduced progesterone receptor-induced transcription. Kinetic experiments revealed that a loss of chromatin-remodeling proteins was coincident with the decrease in MMTV transcriptional activity and the imposition of repressed chromatin architecture at the promoter. These results demonstrate that deacetylase inhibitor treatment at levels that induce global histone acetylation may leave specific regulatory regions relatively unaffected and that this treatment may lead to transcriptional inhibition by mechanisms that modify chromatin-remodeling proteins rather than by influencing histone acetylation of the local promoter chromatin structure.


Assuntos
Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Vírus do Tumor Mamário do Camundongo/genética , Regiões Promotoras Genéticas , Receptores de Progesterona/fisiologia , Ativação Transcricional/efeitos dos fármacos , Acetilação , Sequência de Bases , Linhagem Celular , Primers do DNA , Proteínas de Ligação a DNA/química , Humanos , Fatores de Transcrição NFI , Moldes Genéticos , Fatores de Transcrição/química , Ativação Transcricional/fisiologia
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