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1.
Proc Natl Acad Sci U S A ; 105(35): 12725-9, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18753633

RESUMO

Using NMR, we measure the proton chemical shift delta, of supercooled nanoconfined water in the temperature range 195 K < T < 350 K. Because delta is directly connected to the magnetic shielding tensor, we discuss the data in terms of the local hydrogen bond geometry and order. We argue that the derivative -( partial differential ln delta/ partial differentialT)(P) should behave roughly as the constant pressure specific heat C(P)(T), and we confirm this argument by detailed comparisons with literature values of C(P)(T) in the range 290-370 K. We find that -( partial differential ln delta/ partial differentialT)(P) displays a pronounced maximum upon crossing the locus of maximum correlation length at approximately 240 K, consistent with the liquid-liquid critical point hypothesis for water, which predicts that C(P)(T) displays a maximum on crossing the Widom line.

2.
Oncol Rep ; 4(4): 779-85, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-21590139

RESUMO

Vitamins A and E play an important role against 'free radicals' (FRs). Their antioxidant action is evident in neoplastic disease (ND) that is known to have a FRs pathology. This finding has been supported by previous research showing increased lipid peroxidation of the erythrocyte membrane with increased permeability and higher hemoglobin susceptibility to oxidative stress. Connections exist between the two vitamins and FRs lipid peroxidation of the membranes. In order to study A and E vitamin behaviour in ND, they were assayed in the sera of 88 cancer patients versus 94 healthy subjects. In the 88 cancer cases, without considering variables such as age, sex and smoking habits, the average amount of vitamin A was 47.44+/-19.60 mu g/dl versus 71.77+/-18.30 in controls (P<0.0001). The average amount of vitamin E was 1144.42+/-507.45 in ND versus 1497.45+/-397.74 in controls (P<0.0001). The two vitamins were simultaneously assayed in the same serum by high pressure liquid chromatography. The method is rapid and gave exact and repeatable results. Reasons for vitamin decrease are discussed.

3.
Anticancer Res ; 15(5B): 2089-95, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8572607

RESUMO

The role played by free radicals in carcinogenesis and their relationships with antioxidant pool and cancer have already been shown. Free radicals induce increased membrane permeability through membrane lipid peroxidation, protein oxidation and histamine release from mast cells. Free radicals also cause oxyhemoglobin oxidative stress which increases methemoglobin and hemichromes. For this reason, we studied the in vitro formation of methemoglobin at 0' and 90', dosed following the HPLC method, after oxidative stress of blood by means of acetylphenylhydrazine in 40 subjects with cancer and 40 healthy donors. The results showed that methemoglobin formation was highly significant in tumors as compared to controls (P < 0.0001). The statistical analyses we carried out showed that metHb formation is not affected by age, sex, smoking habit, red blood cell number, Hb, Ht or tumor staging. This makes us believe that free radicals alter erythrocyte membrane permeability and predenaturate oxyhemoglobin so that erythrocyte membrane becomes more susceptible to new oxidative stress. This caused the abnormal response we found. Our results clearly underline the role played by free radicals in tumorous disease and provide a successful and easy method to detect early, even in a pre-clinical stage, the presence of tumorous alterations in the human body.


Assuntos
Hemoglobinas/metabolismo , Neoplasias/sangue , Estresse Oxidativo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Metemoglobina/metabolismo , Pessoa de Meia-Idade
4.
Anticancer Res ; 16(4A): 1749-54, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8712695

RESUMO

The blood of the subjects suffering from Neoplastic Disease (ND) shows phenomena of membrane peroxidation due to the presence of Free Radicals (FRs), in a quantity much greater than the one observed in the blood of healthy subjects. This can be detected either by calculating the time necessary for the formation of "Heinz bodies" (Hbs), (p < 0.00001) after oxidative stress of the blood in vitro with acetylphenylidrazine (APH), or by calculating the methemoglobin (metHb) quantity that forms after the same treatment (P < 0.00001). The statistical analyses we carried out showed that metHb formation was not affected by age, sex, smoking habits, red blood cell number, Hb, Ht or tumor staging. In this study, by using equal parameters of investigation, we noted that the blood of the subjects with ND who were previously treated with calcium-antagonists drugs and with antagonists of H1 and H2 receptors, gave results completely superimposable on the results obtained from healthy subjects, implying that the treatment had avoided the increase of FRs. Therefore we concluded that calcium-antagonists and the antagonists of the H1 and H2 receptors behave as antioxidant substances, having decreased the FRs damaging activity on the cellular membranes, thus controlling, although to a limited degree, the pejorative evolution of the disease. It is also important to remember that investigations into the ND, even possible screenings, must take into account the above said data, submitting the subjects under investigation to a pharmacological wash out, particularly with those substances which, are considered to be scavengers of FRs. Some of these substances are investigated in this work.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Sequestradores de Radicais Livres/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Metemoglobina/metabolismo , Neoplasias/sangue , Análise de Variância , Cimetidina/toxicidade , Humanos , Metemoglobina/efeitos dos fármacos , Pessoa de Meia-Idade , Nicardipino/uso terapêutico , Nifedipino/uso terapêutico , Omeprazol/uso terapêutico , Estresse Oxidativo , Fenil-Hidrazinas/farmacologia , Ranitidina/uso terapêutico , Valores de Referência
5.
Anticancer Res ; 18(2A): 1075-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9615768

RESUMO

Results obtained from blood sample readings by optical microscopy and He-Ne laser (lambda = 630.1 mW), have confirmed the reduction in Heinz Bodies (HB) formation time and the Transmittance Reduction Degree (TRD), in malignancies. The results of spectrometric readings in colorectum polyposis, (TRD = 0.07) and fibrocystic mastopathy (TRD = 0.08) gave results overlapping with controls (TRD = 0.08). In neoplasias, the early HB formation in erythrocytes observed by optical microscope corresponded to TRD increase = 0.17 (P < 0.01). TRD increase was statistically significant (P < 0.01), as well as the reduction in the time of HB appearance (< 0.01). The relationship between optical and laser readings was exponential in tumors, while it was linear in controls, in polyposis and mastopathies. The values of the correlation coefficients obtained by both methods were significant (P < 0.01) for all the studied groups. Moreover, these research data further support the existence, even in the earlier stages of the disease, of the labile state of the red cell membrane due to strong lipid peroxidation by FRs.


Assuntos
Eritrócitos/ultraestrutura , Corpos de Heinz/ultraestrutura , Neoplasias/sangue , Feminino , Radicais Livres , Humanos , Lasers , Masculino , Microscopia
6.
Anticancer Res ; 20(3A): 1595-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10928076

RESUMO

As reported in previous investigations, erythrocytes are the elements of peripheral blood most affected by free radical activity in the pathogenesis of cancer. In these studies, the level of sulphydrilic groups and reduced glutathione were assayed in the erythrocytes and plasma, while their successful scavenger activity against cell membrane oxidation and peroxidation has already been established. In subjects with cancer, the levels of -SH groups (p < 0.002) and reduced glutathione in both plasma and erythrocytes (p < 0.0001) were shown be a statistically significantly decreased compared to healthy controls. These differences were related to the defence of the hematic tissue against free radical activity. A similar pattern has also been reported when studying vitamin A and E content in the peripheral blood of cancer patients. The role of oxido-reduction phenomena in this disease is discussed, as well as the importance of reducing the oxido-peroxidation involvement of tissues and cell elements. The study of the GSH/GSSG ratio in order to determine the stage of the disease would be useful and might represent a systemic marker for cancerous lesions.


Assuntos
Adenocarcinoma/sangue , Neoplasias do Colo/sangue , Glutationa/sangue , Compostos de Sulfidrila/sangue , Humanos , Masculino , Pessoa de Meia-Idade
7.
Minerva Chir ; 55(1-2): 65-7, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-10832287

RESUMO

The case of a patient affected by an epithelial hemangioendothelioma of the arm is described. A definitive diagnosis was possible only by histologic examination. The difficulty to reliably predict the biological behaviour of these tumors is emphasized and therefore the necessity of a follow-up of the patient for many years is stressed, even in the case of a histologically benign tumor.


Assuntos
Fáscia , Hemangioendotelioma Epitelioide , Neoplasias Musculares , Adulto , Braço , Fáscia/patologia , Fasciotomia , Feminino , Seguimentos , Hemangioendotelioma Epitelioide/patologia , Hemangioendotelioma Epitelioide/cirurgia , Humanos , Neoplasias Musculares/patologia , Neoplasias Musculares/cirurgia , Fatores de Tempo
8.
G Chir ; 19(5): 204-6, 1998 May.
Artigo em Italiano | MEDLINE | ID: mdl-9677770

RESUMO

The Authors report a case of spontaneous spleen rupture in a woman with breast cancer treated with chemotherapy and growth factors for stem cell mobilization. After a wide review of the literature, they suppose this therapy, causing a considerable increase of immature cells, that promote the stasis of the splenic microcirculation, can sometime elicit a spontaneous rupture of the organ.


Assuntos
Neoplasias da Mama/terapia , Baço/lesões , Adulto , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Terapia Combinada , Feminino , Mobilização de Células-Tronco Hematopoéticas , Humanos , Ruptura Espontânea , Baço/efeitos dos fármacos
9.
G Chir ; 19(11-12): 453-7, 1998.
Artigo em Italiano | MEDLINE | ID: mdl-9882948

RESUMO

The Authors describing a case of Spigelian hernia observed point out clinical, diagnostic and therapeutic considerations about this rare pathology of abdominal wall. They specify the anatomic characteristics of the region and underline as any diagnostic difficulties are by passed by use of USG and TC imaging for formulation of correct preoperative diagnosis. They confirm as surgical treatment by a correct access isn't different by a normal hernioplasty and guarantee the long term surgical outcome.


Assuntos
Hérnia Ventral , Feminino , Hérnia Ventral/diagnóstico por imagem , Hérnia Ventral/cirurgia , Humanos , Pessoa de Meia-Idade , Radiografia , Ultrassonografia
10.
J Chem Phys ; 124(16): 161102, 2006 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-16674122

RESUMO

By means of a nuclear magnetic resonance experiment, we give evidence of the existence of a fragile-to-strong dynamic crossover transition (FST) in confined water at a temperature T(L)=223+/-2 K. We have studied the dynamics of water contained in 1D cylindrical nanoporous matrices (MCM-41-S) in the temperature range 190-280 K, where experiments on bulk water were so far hampered by crystallization. The FST is clearly inferred from the T dependence of the inverse of the self-diffusion coefficient of water (1D) as a crossover point from a non-Arrhenius to an Arrhenius behavior. The combination of the measured self-diffusion coefficient D and the average translational relaxation time tau(T), as measured by neutron scattering, shows the predicted breakdown of Stokes-Einstein relation in deeply supercooled water.

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