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1.
Horm Metab Res ; 48(7): 440-5, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27101095

RESUMO

Primary aldosteronism (PA) is one of the most frequent forms of secondary hypertension, associated with atherosclerosis and higher risk of cardiovascular events. Platelets play a key role in the atherosclerotic process. The aim of the study was to evaluate the platelet activation by measuring serum levels of soluble CD40L (sCD40L) and P-selectin (sP-selectin) in consecutive PA patients [subgroup: aldosterone-secreting adrenal adenoma (APA) and bilateral adrenal hyperplasia (IHA)], matched with essential hypertensive (EH) patients. The subgroup of APA patients was revaluated 6-months after unilateral adrenalectomy. In all PA group, we measured higher serum levels of both sP-selectin (14.29±9.33 pg/ml) and sCD40L (9.53±4.2 ng/ml) compared to EH patients (9.39±5.3 pg/ml and 3.54±0.94 ng/ml, respectively; p<0.001). After removal of APA, PA patients showed significant reduction of blood pressure (BP) values, plasma aldosterone (PAC) levels and ARR-ratio, associated with a significant reduction of sP-selectin (16.74±8.9 pg/ml vs. 8.1±3.8 pg/ml; p<0.01) and sCD40L (8.6±1 ng/ml vs. 5.24±0.94 ng/ml; p<0.001). In PA patients, we found a significant correlation between sP-selectin and sCD40L with PAC (r=0.52, p<0.01; r=0.50, p<0.01, respectively); this correlation was stronger in APA patients (r=0.54; p<0.01 r=0.63; p<0.01, respectively). Our results showed that PA is related to platelet activation, expressed as higher plasma values of sCD40L and sP-selectin values. Surgical treatment and consequent normalization of aldosterone secretion was associated with significant reduction of sCD40L and sP-selectin values in APA patients.


Assuntos
Ligante de CD40/sangue , Hiperaldosteronismo/sangue , Selectina-P/sangue , Adenoma Adrenocortical/sangue , Adenoma Adrenocortical/urina , Aldosterona/urina , Antropometria , Feminino , Humanos , Hiperaldosteronismo/urina , Hipertensão/sangue , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Solubilidade
2.
Phys Med Biol ; 60(20): 7805-28, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26406277

RESUMO

Water is a common surrogate of DNA for modelling the charged particle-induced ionizing processes in living tissue exposed to radiations. The present study aims at scrutinizing the validity of this approximation and then revealing new insights into proton-induced energy transfers by a comparative analysis between water and realistic biological medium. In this context, a self-consistent quantum mechanical modelling of the ionization and electron capture processes is reported within the continuum distorted wave-eikonal initial state framework for both isolated water molecules and DNA components impacted by proton beams. Their respective probability of occurrence-expressed in terms of total cross sections-as well as their energetic signature (potential and kinetic) are assessed in order to clearly emphasize the differences existing between realistic building blocks of living matter and the controverted water-medium surrogate. Consequences in radiobiology and radiotherapy will be discussed in particular in view of treatment planning refinement aiming at better radiotherapy strategies.


Assuntos
DNA/química , Prótons , Radiobiologia , Radioterapia , Água/química , Elétrons , Metabolismo Energético , Humanos , Cinética
3.
Acta Clin Belg ; 69(3): 204-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24820919

RESUMO

UNLABELLED: CASE BACKGROUND: Ascites appears mainly as a consequence of portal hypertension in patients with liver cirrhosis, or can be caused by several other causes, such us congestive heart failure, peritoneal malignancy, or tuberculosis. In some cases, ascites can pose a diagnostic challenge for clinicians and in some patients, despite thorough and extensive work-up, the origin of this ascites remains unknown. CASE REPORT: In the unusual case hereby reported, a 52-year-old man developed severe ascites in a few weeks, in the absence of known liver disease or congestive hearth failure. We performed laboratory analysis, endoscopic, and imaging investigations, including abdominal contrast-enhanced computed tomography and 18-fluorodeoxyglucose-positron emission tomography. Peritoneal fluid analysis showed exudative fluid without neoplastic cells. A diagnostic laparoscopy with multiple diagnostic biopsies was carried out, but no macroscopic cause of the ascites was found; histopathological examination showed minimal aspects of diffuse and non-specific chronic inflammation. CONCLUSIONS: We decided to empirically treat the patient with steroid therapy (methylprednisolone: 0·5 mg/kg/day). Over a period of 6 weeks, his ascites resolved and at 2 months, he was in remission on low-dose methylprednisolone. Our final hypothesis was reactive inflammatory ascites. The literature on ascites and its management has also been reviewed.


Assuntos
Ascite/diagnóstico , Ascite/etiologia , Anti-Inflamatórios/uso terapêutico , Ascite/tratamento farmacológico , Humanos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade
4.
Appl Radiat Isot ; 83 Pt B: 105-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23415107

RESUMO

Distorted wave models are employed to investigate the electron loss process induced by bare ions on biological targets. The two main reactions which contribute to this process, namely, the single electron ionization as well as the single electron capture are here studied. In order to further assess the validity of the theoretical descriptions used, the influence of particular mechanisms are studied, like dynamic screening for the case of electron ionization and energy deposition on the target by the impacting projectile for the electron capture one. Results are compared with existing experimental data.


Assuntos
Elétrons , Íons , Modelos Teóricos , Probabilidade
5.
Med Phys ; 40(6): 064101, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23718619

RESUMO

PURPOSE: The LIonTrack (Light Ion Track) Monte Carlo (MC) code for the simulation of H(+), He(2+), and other light ions in liquid water is presented together with the results of a novel investigation of energy-deposition site properties from single ion tracks. METHODS: The continuum distorted-wave formalism with the eikonal initial state approximation (CDW-EIS) is employed to generate the initial energy and angle of the electrons emitted in ionizing collisions of the ions with H2O molecules. The model of Dingfelder et al. ["Electron inelastic-scattering cross sections in liquid water," Radiat. Phys. Chem. 53, 1-18 (1998); "Comparisons of calculations with PARTRAC and NOREC: Transport of electrons in liquid water," Radiat. Res. 169, 584-594 (2008)] is linked to the general-purpose MC code PENELOPE/penEasy to simulate the inelastic interactions of the secondary electrons in liquid water. In this way, the extended PENELOPE/penEasy code may provide an improved description of the 3D distribution of energy deposits (EDs), making it suitable for applications at the micrometer and nanometer scales. RESULTS: Single-ionization cross sections calculated with the ab initio CDW-EIS formalism are compared to available experimental values, some of them reported very recently, and the theoretical electronic stopping powers are benchmarked against those recommended by the ICRU. The authors also analyze distinct aspects of the spatial patterns of EDs, such as the frequency of nearest-neighbor distances for various radiation qualities, and the variation of the mean specific energy imparted in nanoscopic targets located around the track. For 1 MeV/u particles, the C(6+) ions generate about 15 times more clusters of six EDs within an ED distance of 3 nm than H(+). CONCLUSIONS: On average clusters of two to three EDs for 1 MeV/u H(+) and clusters of four to five EDs for 1 MeV/u C(6+) could be expected for a modeling double strand break distance of 3.4 nm.


Assuntos
Íons/química , Transferência Linear de Energia , Modelos Estatísticos , Nanopartículas/química , Prótons , Espalhamento de Radiação , Software , Água/química
6.
Ultraschall Med ; 34(3): 280-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23616066

RESUMO

PURPOSE: To assess the impact of different vascular patterns at contrast-enhanced ultrasound (CEUS) on the characterization of small liver nodules (10-30 mm) in cirrhosis and to determine whether primary nodules and recurrent nodules (after a previously treated hepatocellular carcinoma) display variations in enhancement pattern. MATERIALS AND METHODS: A total of 135 cirrhotic patients were evaluated. A diagnosis of hepatocellular carcinoma (HCC) was established according to AASLD Guidelines, based on imaging (computed tomography and/or magnetic resonance) or liver biopsy. All patients underwent CEUS. Different CEUS patterns were evaluated in terms of diagnostic accuracy: HYPER-HYPO: Arterial hyperenhancement followed by washout (hypoechoic appearance compared with surrounding parenchyma) in late phase; HYPER-ISO: Arterial hyperenhancement followed by isoenhancement (isoechoic appearance) in late phase; ISO-ISO: Isoenhancement in all vascular phases. RESULTS: A total of 155 consecutive primary (n = 90) or recurrent (n = 65) nodules were detected. HCC was diagnosed in 127 nodules (71 primary, 56 recurrent). A characteristic HYPER-HYPO CEUS pattern was revealed in 52/127 (40.9%) HCCs (31 primary, 21 recurrent) giving a positive predictive value (PPV) of 98% (97% primary, 100% recurrent) and an accuracy of 51% (54% primary, 46% recurrent). A HYPER-ISO pattern was noted in 46 HCCs (31 primary, 15 recurrent). Assuming this pattern to also be indicative of HCC, the PPV and accuracy were 94% (93% primary, 97% recurrent) and 77% (84% primary, 68% recurrent), respectively. An ISO-ISO pattern was present in 29 HCCs (9 primary, 20 recurrent) and 22 non-HCCs (14 primary, 8 recurrent). CONCLUSION: These data confirm that the HYPER-HYPO pattern at CEUS is definitely diagnostic for HCC in cirrhosis and that the HYPER-ISO pattern has a similar PPV, indicating that this pattern is highly suspicious for HCC. The ISO-ISO pattern was found in > 50% of recurrent nodules and indicates a high risk of HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Hiperplasia Nodular Focal do Fígado/diagnóstico por imagem , Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Idoso , Biópsia , Carcinoma Hepatocelular/patologia , Feminino , Hiperplasia Nodular Focal do Fígado/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Recidiva Local de Neoplasia/patologia , Sensibilidade e Especificidade , Ultrassonografia
7.
Aliment Pharmacol Ther ; 37(3): 355-63, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23199022

RESUMO

BACKGROUND: Gadoxetic acid (Gd-EOB-DTPA) is a 'hepatocyte-specific' contrast agent for magnetic resonance (MR) in both the vascular and the hepatobiliary phases. AIM: To evaluate the contribution of the hepatobiliary phase of Gd-EOB-DTPA MR in the diagnosis of small hepatocellular carcinoma (HCC) in cirrhotic patients under surveillance. METHODS: Between 2008 and 2011, 48 consecutive small (10-30 mm) liver nodules were detected in 33 patients, who prospectively underwent contrast-enhanced ultrasound (CEUS), Gd-EOB-DTPA-enhanced MR and helical-computed tomography (CT) in a blind study. The diagnosis of HCC was established according to AASLD 2005 criteria. RESULTS: Of the 48 nodules, 38 (79%) were diagnosed as HCC, 24 (63%) of them based on AASLD non-invasive criteria, 11 diagnosed at histology and 3 during follow-up. The typical vascular pattern (arterial hypervascularisation and venous/late washout) was detected in 30 (79%) HCC nodules by MR, in 22 (58%) by CT and in 17 (45%) by CEUS. Hypointensity during the MR hepatobiliary phase was observed in all HCC nodules and in 3 nonmalignant nodules (sensitivity 100%, specificity 70%, positive predictive value 93%, negative predictive value 100%, positive likelihood ratio 3.33, negative likelihood ratio 0). Eight (21%) of the 38 HCC nodules, 7 of which lacked the typical vascular features at any of the imaging modalities, showed washout in the portal/venous phase and hypointensity in the hepatobiliary phase at MRI, while this pattern was not detected in any nonmalignant lesion. CONCLUSIONS: Gadoxetic acid magnetic resonance may enhance the sensitivity of the non-invasive diagnosis of small hepatocellular carcinoma nodules in cirrhotic patients under surveillance. Double hypointensity in the portal/venous and hepatobiliary phases could be considered a new magnetic resonance pattern, highly suggestive of hypovascular hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Meios de Contraste , Gadolínio DTPA , Neoplasias Hepáticas/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
8.
J Hepatol ; 57(6): 1258-67, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22871502

RESUMO

BACKGROUND & AIMS: Aim of the study was to assess the clinical impact of conventional transarterial chemoembolization (cTACE) repeated "on demand" on HCC outcome. Outcome measures were: response rate to first and repeated cTACE, recurrence rates and overall survival. METHODS: The outcome of 151 consecutive HCC patients submitted to a first cTACE from January 2004 to December 2005 was retrospectively analyzed. RESULTS: Complete radiological response (CR) was observed in 72/151 (48%), 34/60 (52%) and 12/22 (55%) patients after first, second and third cTACE, respectively. Recurrence rates at 6 and 12months were 37% and 61% after the first cTACE, and 40% and 59% after the second cTACE, respectively. Patients not achieving CR or with a recurrence after CR not treated with curative therapies were 94 and 84 after first and second cTACE, respectively. Of these, 60/94 (64%) and 22/84 (26%) were submitted to a second and third cTACE, respectively. Median overall survival was 32.0months but 25.0months excluding transplanted patients. Factors at the time of first cTACE associated with overall shorter survival at multivariate analysis were higher bilirubin, higher AFP and not achieving CR. CONCLUSIONS: CR and recurrence rates after first and second cTACE were similar. About 64% of patients were submitted to second cTACE, while only few patients (26%) were submitted to third cTACE using an "on demand" policy. These figures may be also useful for planning trials for the evaluation of the efficacy of repeated TACE vs. TACE combined with adjuvant treatments or vs. systemic treatments.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia
9.
Phys Med Biol ; 57(10): 3039-49, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22538416

RESUMO

In this work, we report total cross sections for the single electron capture process induced on DNA/RNA bases by high-energy protons. The calculations are performed within both the continuum distorted wave and the continuum distorted wave-eikonal initial state approximations. The biological targets are described within the framework of self-consistent methods based on the complete neglect of differential overlap model whose accuracy has first been checked for simpler bio-molecules such as water vapour. Furthermore, the multi-electronic problem investigated here is reduced to a mono-electronic one using a version of the independent electron approximation. Finally, the obtained theoretical predictions are confronted with the scarcely available experimental results.


Assuntos
DNA/química , Elétrons , Prótons , RNA/química
10.
Phys Med Biol ; 57(7): 2081-99, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22433314

RESUMO

Among the numerous constituents of eukaryotic cells, the DNA macromolecule is considered as the most important critical target for radiation-induced damages. However, up to now ion-induced collisions on DNA components remain scarcely approached and theoretical support is still lacking for describing the main ionizing processes. In this context, we here report a theoretical description of the proton-induced ionization of the DNA and RNA bases as well as the sugar-phosphate backbone. Two different quantum-mechanical models are proposed: the first one based on a continuum distorted wave-eikonal initial state treatment and the second perturbative one developed within the first Born approximation with correct boundary conditions (CB1). Besides, the molecular structure information of the biological targets studied here was determined by ab initio calculations with the Gaussian 09 software at the restricted Hartree-Fock level of theory with geometry optimization. Doubly, singly differential and total ionization cross sections also provided by the two models were compared for a large range of incident and ejection energies and a very good agreement was observed for all the configurations investigated. Finally, in comparison with the rare experiment, we have noted a large underestimation of the total ionization cross sections of uracil impacted by 80 keV protons,whereas a very good agreement was shown with the recently reported ionization cross sections for protons on adenine, at both the differential and the total scale.


Assuntos
DNA/química , Prótons , Teoria Quântica , RNA/química , Modelos Moleculares , Conformação de Ácido Nucleico
11.
Minerva Stomatol ; 60(1-2): 15-23, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21252846

RESUMO

AIM: The aim of this paper was to compare the dentin-pulp complex response to cavity preparation in human teeth using ultrasonic chemical vapor deposition (CVD) diamond tip and high-speed diamond bur. METHODS: Class V buccal cavities were randomly prepared in 40 premolars from 14 patients aged 11 to 15 years. The cutting time was recorded and the cavities had the axial walls protected with gutta-percha and were filled with glass ionomer cement. The teeth were extracted at intervals of 0, 5, 10 and 20 days, and were decalcified, sectioned and stained by Hematoxylin & Eosin, Masson's Trichrome and Brown & Brenn techniques. The inflammatory response and cell disorganization were blindly evaluated by two examiners. The remaining dentin thickness (RDT) was measured by a linear scale using computer software. Statistical analysis by one-way ANOVA showed no statistically significant difference (P≤0.05) among the cavities prepared with either type of instrument, with mean RDT of 1132.50 mm. Cutting time and the pulp-dentin complex responses were analyzed statistically by Kruskal-Wallis and Dunn tests (P≤0.05). RESULTS: The ultrasonic CVD diamond tip took 5 times longer to prepare the cavities and there were no typical inflammatory pulp responses in cavities prepared with either type of cutting instrument, only mild to moderate cell disorganization was present. CONCLUSION: Even taking longer to cut the dental substrate, the ultrasonic CVD diamond tip produced similar pulp response compared to the conventional high-speed diamond bur.


Assuntos
Dente Pré-Molar/ultraestrutura , Preparo da Cavidade Dentária/efeitos adversos , Equipamentos Odontológicos de Alta Rotação , Cavidade Pulpar/ultraestrutura , Dentina/ultraestrutura , Adolescente , Dente Pré-Molar/cirurgia , Criança , Preparo da Cavidade Dentária/instrumentação , Diamante , Cimentos de Ionômeros de Vidro , Guta-Percha , Humanos , Inflamação/etiologia , Odontometria , Método Simples-Cego , Coloração e Rotulagem , Fatores de Tempo , Extração Dentária , Ultrassom
12.
Phys Med Biol ; 55(20): 6053-67, 2010 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-20858921

RESUMO

Induction of DNA double strand breaks after irradiation is considered of prime importance for producing radio-induced cellular death or injury. However, up to now ion-induced collisions on DNA bases remain essentially experimentally approached and a theoretical model for cross section calculation is still lacking. Under these conditions, we here propose a quantum mechanical description of the ionization process induced by light bare ions on DNA bases. Theoretical predictions in terms of differential and total cross sections for proton, α-particle and bare ion carbon beams impacting on adenine, cytosine, thymine and guanine bases are then reported in the 10 keV amu(-1)-10 MeV amu(-1) energy range. The calculations are performed within the first-order Born approximation (FBA) with biological targets described at the restricted Hartree-Fock level with geometry optimization. Comparisons to recent theoretical data for collisions between protons and cytosine point out huge discrepancies in terms of differential as well as total cross sections whereas very good agreement is shown with our previous classical predictions, especially at high impact energies (E(i) ≥ 100 keV amu(-1)). Finally, in comparison to the rare existing experimental data a systematic underestimation is observed in particular for adenine and thymine whereas a good agreement is reported for cytosine. Thus, further improvements appear as necessary, in particular by using higher order theories like the continuum-distorted-wave one in order to obtain a better understanding of the underlying physics involved in such ion-DNA reactions.


Assuntos
DNA/química , Teoria Quântica , Partículas alfa , Carbono/farmacologia , DNA/genética , Dano ao DNA , Íons , Prótons
13.
J Chem Phys ; 131(2): 024302, 2009 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-19603986

RESUMO

We present a detailed study of the potential energy surfaces of the water dication correlating asymptotically with O((3)P) and O((1)D). Using ab initio multireference configuration interaction method, we computed a large ensemble of data, which was used to generate a fit of each potential energy surface for bending angles theta > or = 80 degrees degrees and OH distances R(OH) > or = 1.0 a.u. The fit is used to investigate the dissociation dynamics along each potential energy surface for several initial geometries corresponding to Franck-Condon transition from neutral or singly ionized water molecule. For each case, we determine the dissociation channels and we compute the kinetic energy release and angular momentum distribution of the final arrangements. Among the eight potential energy surfaces investigated here, only the lowest triplet and the three lowest singlet can lead to the formation of bound residual fragment. The dissociation of HOD(2+) presents a strong preference for OH rather than OD bond breakage. It is characterized by the isotopic ratio, defined as the number of OD(+) over the number of OH(+) residual fragments. This ratio depends strongly on the shape of each potential energy surface and on the initial conditions.

14.
Nature ; 437(7060): 855-8, 2005 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-16208364

RESUMO

Gamma-ray bursts (GRBs) fall into two classes: short-hard and long-soft bursts. The latter are now known to have X-ray and optical afterglows, to occur at cosmological distances in star-forming galaxies, and to be associated with the explosion of massive stars. In contrast, the distance scale, the energy scale and the progenitors of the short bursts have remained a mystery. Here we report the discovery of a short-hard burst whose accurate localization has led to follow-up observations that have identified the X-ray afterglow and (for the first time) the optical afterglow of a short-hard burst; this in turn led to the identification of the host galaxy of the burst as a late-type galaxy at z = 0.16 (ref. 10). These results show that at least some short-hard bursts occur at cosmological distances in the outskirts of galaxies, and are likely to be caused by the merging of compact binaries.

15.
Nature ; 435(7039): 178-80, 2005 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-15889084

RESUMO

The prompt optical emission that arrives with the gamma-rays from a cosmic gamma-ray burst (GRB) is a signature of the engine powering the burst, the properties of the ultra-relativistic ejecta of the explosion, and the ejecta's interactions with the surroundings. Until now, only GRB 990123 had been detected at optical wavelengths during the burst phase. Its prompt optical emission was variable and uncorrelated with the prompt gamma-ray emission, suggesting that the optical emission was generated by a reverse shock arising from the ejecta's collision with surrounding material. Here we report prompt optical emission from GRB 041219a. It is variable and correlated with the prompt gamma-rays, indicating a common origin for the optical light and the gamma-rays. Within the context of the standard fireball model of GRBs, we attribute this new optical component to internal shocks driven into the burst ejecta by variations of the inner engine. The correlated optical emission is a direct probe of the jet isolated from the medium. The timing of the uncorrelated optical emission is strongly dependent on the nature of the medium.

16.
Acta Obstet Gynecol Scand ; 75(3): 208-12, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8607330

RESUMO

BACKGROUND: To evaluate the effects of L-arginine (ARG) infusion, the nitric oxide as substrate, on the utero-placental circulation at third trimester. METHODS: Three groups of nine pregnant women each were infused i.v. with 30 g ARG, for 30 minutes. One group served as control, and the two remnants were composed by patients with intrauterine growth retardation with (IUGR-B) or without (IUGR-A) increased resistances in the utero-placental circulation. Changes of blood flow velocity waveforms of both uterine arteries and umbilical artery were recorded for 60 minutes. Blood pressure, serum nitrites/nitrates and growth hormone levels were also measured. RESULTS: No hemodynamic changes in utero-umbilical circulation were observed during infusion in any of the three groups. Considering the uterine arteries separately as placental and non-placental sided we found a significant decrease of non-placental side resistances in IUGR-B women. Indeed, the pulsatility index was lowered by 14%, in respect of baseline value. Serum nitrites/nitrates as well as serum growth hormone levels were significantly increased by ARG, in every woman, irrespective of the presence of fetal growth retardation. Blood pressure remained unaffected during infusion in every woman. CONCLUSIONS: These findings suggest that L-arginine infusion affects utero-placental circulation in patients with IUGR associated with increased uterine resistances. Such an action is specific and appears possibly to be mediated by a release of nitric oxide.


Assuntos
Arginina/farmacologia , Retardo do Crescimento Fetal , Circulação Placentária/efeitos dos fármacos , Adulto , Arginina/administração & dosagem , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Feminino , Retardo do Crescimento Fetal/sangue , Humanos , Infusões Parenterais , Idade Materna , Neurotransmissores/metabolismo , Ácido Nítrico/sangue , Óxido Nítrico/metabolismo , Nitritos/sangue , Paridade , Gravidez
17.
J Endocrinol Invest ; 18(1): 51-6, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7759785

RESUMO

The use of luteal phase support has been demonstrated in patients undergoing IVF/ET in cycles stimulated after pituitary desensitization with gonadotrophin releasing hormone agonists. However, it is still not clear which is the most suitable kind of supplementation. This study was designed to compare the absorption and the efficacy of three different luteal support. We randomly administered progesterone i.m. (50 mg/day), human chorionic gonadotrophin (hCG) (2000 IU every three days), progesterone vaginal cream (100 mg/day) or nothing (controls) to 176 women treated for assisted procreation. We were not able to show any statistical differences for the percentage of pregnancy rate between groups. The serum progesterone (P) and 17-beta-estradiol (E2) and E2/P ratio levels of the luteal phase were compared with the control not supplemented group. All the treatments were able to increase significantly the luteal P values versus controls (p < 0.01). Moreover, vaginal cream and natural P im significantly decreased E2/P ratio (p < 0.05). Serum P levels were more steady with P vaginal cream than im injection. Vaginal cream for better bioavailability and acceptance appear the most suitable and comfortable method for luteal phase support.


Assuntos
Transferência Embrionária , Fertilização in vitro , Fase Luteal , Progesterona/uso terapêutico , Adulto , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/uso terapêutico , Estradiol/sangue , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Gravidez , Progesterona/administração & dosagem , Progesterona/sangue , Cremes, Espumas e Géis Vaginais
18.
Phys Rev D Part Fields ; 47(8): 3254-3264, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10015944
19.
J Clin Endocrinol Metab ; 74(6): 1427-31, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1375601

RESUMO

CRF, a hypothalamic neurohormone, has been shown to be present in several tissues outside the brain. During pregnancy, both fetal (placental trophoblast, chorion, and amnion) and maternal (decidua) intrauterine tissues contain immunoreactive CRF. A paracrine/autocrine role of CRF as a regulator of hormonogenesis in human placenta and decidua has been suggested. The expression of CRF mRNA in human decidua was demonstrated in the present study by Northern blot analysis and was found to be higher in specimens collected at term than in those collected during the first and second trimesters of gestation. Furthermore, the presence of CRF was detected immunocytochemically in cultured decidual cells isolated from term decidua as well as in endometrial stromal cells decidualized in vitro by treatment with a mixture of medroxyprogesterone acetate, estradiol, and relaxin. These results indicate that human decidua is an intrauterine extrahypothalamic source of CRF in the maternal compartment and offer new tools to explore the in vitro decidualization processes and the regulation of CRF release from decidual cells.


Assuntos
Hormônio Liberador da Corticotropina/análise , Decídua/fisiologia , Endométrio/fisiologia , Gravidez/fisiologia , RNA Mensageiro/análise , Trofoblastos/fisiologia , Aborto Espontâneo , Northern Blotting , Cesárea , Hormônio Liberador da Corticotropina/genética , Decídua/citologia , Endométrio/citologia , Feminino , Humanos , Imuno-Histoquímica , Poli A/genética , Poli A/isolamento & purificação , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro/genética , Trofoblastos/citologia
20.
Eur J Obstet Gynecol Reprod Biol ; 41(2): 117-22, 1991 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-1834488

RESUMO

To assess the influence of diminished oestrogen production on bone density, we studied 23 amenorrhoeic women and 20 controls (age range 16-29 years) divided into four groups: group 1: 6 patients with idopathic hypogonadotrophic hypogonadism with primary amenorrhoea (IHH); group 2: 5 patients with delayed puberty owing to thalassaemia major (TM); group 3: 12 patients with secondary hypothalamic amenorrhoea (HA); group 4: 20 women with normal menses (controls). Secondary sexual characteristics had developed in all except the women with TM. Groups 1 and 2 had never menstruated and group 3 had been amenorrhoeic for 6 months to 3 years. The control group was studied during the follicular phase of the cycle. None of the patients were taking oestrogens at the time of observation. Plasma concentrations were determined for 17 beta-oestradiol (E2), deidroepiandrosterone sulphate (DHEA-S), cortisol (F), prolactin (PRL), thyroid hormones (T3 and T4), and gonadotrophins (LH and FSH). Spinal bone mineral density (BMD g/cm2) was assessed by dual photon absorbiometry. BMD (mean +/- 1SD) was reduced in the patients (group 2: 0.920 +/- 0.95; group 1: 0.980 +/- 0.94; and group 3: 1.037 +/- 0.75) as compared with the controls (1.290 +/- 0.95) (P less than 0.01). In the three groups of patients, plasma E2 levels were lower than 50 pg/ml and were positively correlated with the BMD. As expected, plasma gonadotrophin levels were highly and significantly reduced (P less than 0.01) in the patients, compared with that of the controls. These results suggest that reduced spinal BMD in hypogonadic women may be related to the lack of oestrogenic influence on bone metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Amenorreia/complicações , Densidade Óssea , Osteoporose/complicações , Doenças da Coluna Vertebral/complicações , Adolescente , Adulto , Amenorreia/fisiopatologia , Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Humanos , Hidrocortisona/sangue , Hormônio Luteinizante/sangue , Osteoporose/fisiopatologia , Prolactina/sangue , Doenças da Coluna Vertebral/fisiopatologia , Hormônios Tireóideos/sangue
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