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1.
Int J Legal Med ; 128(1): 243-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24057124

RESUMEN

One of the most frequently observed lesions in clinical forensic practice concerns the patterned abrasion on skin due to constriction by various types of ligature. Detection of ligature marks and their patterns may be fundamental for reconstructing events and supporting testimony of an aggression, sexual abuse, or maltreatment. But very little actually exists in literature concerning their detectability and how long they last. This study aims at evaluating the time of persistence and detectability of skin signs left by different types of ligatures in living persons: on the arms of three volunteers, eight different ligatures were applied; 123 tests were performed, with time of contact ranging between 1 min and 2 h and 45 min. In addition, the persistence of the shape and pattern of the ligature was evaluated 15, 30, and 60 min after a 5- and 15-min compression. Polyvinyl siloxane, applied by a gun dispenser, was used to perform a cast of the skin mark. The results show that the pattern was less distinguishable with the decrease of time of contact, going from 75 % after 10 and 15 min of contact, to 45.8 % after 1 min. Above 15 min, the specific pattern was always recognizable. In addition, a progressive decrease of the detectability of the pattern with time, respectively, up to 12.5 and 37.5 % in 5- and 15-min tests was observed. This study provides useful results for the assessment of patterned injuries in forensic pathology and clinical forensic medicine, both on dead and living persons: in addition, the use of silicone casts seems to be a reliable and cheap method for easily recording and preserving the morphological profile of skin lesions.


Asunto(s)
Contusiones/diagnóstico , Víctimas de Crimen/legislación & jurisprudencia , Violaciones de los Derechos Humanos/legislación & jurisprudencia , Piel/lesiones , Tortura , Violencia/legislación & jurisprudencia , Adulto , Anciano , Contusiones/clasificación , Contusiones/etiología , Femenino , Humanos , Ligadura , Masculino , Persona de Mediana Edad , Piel/patología , Envejecimiento de la Piel/fisiología
2.
J Am Chem Soc ; 133(16): 6318-22, 2011 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-21452870

RESUMEN

As is well-known, the character of the π orbitals is of paramount importance for the chemical properties of the carbon allotropes and their derived compounds. While at equilibrium the nature of these orbitals is well understood, their photoinduced nonequilibrium behavior is under investigation. Here, we demonstrate that when a UV-laser pulse excites a carrier density larger than 10% of the π* density of state in graphite, a renormalization of the π-π* band gap takes place. This result has been achieved by detecting the transient reflectivity and the associated decay time of an infrared probe following the excitation of a UV pump pulse tuned across the π-π* absorption resonance. The pump photon energy at which both the transient reflectivity and the decay time are maximum is downshifted by 500 meV with respect to the relative absorption maximum at equilibrium. This finding is interpreted as a transient π-π* band gap shrinking of similar magnitude, near the M point of the Brillouin zone.

3.
Med Sci Law ; 51 Suppl 1: S16-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22021627

RESUMEN

The distinction between antemortem and postmortem wounds is one of the most important medico-legal problems. In fresh cadavers the macroscopic examination of haemorrhagic infiltration can be sufficient to reveal the vitality of a wound but in more difficult cases (putrefied corpses) histological and histochemical analyses need to be performed. The scope of this study was to detect the vitality of soft tissue samples in an advanced state of putrefaction using a monoclonal anti-human Glycoforin A antibody in order to evaluate the presence of red blood cells or red blood cell residues. Samples of skin wounds were taken from cadavers with a known time survival between trauma and death, and then submitted to a simulated putrefaction procedure. The skin samples were left to decompose for 30 days in air and in water and analyzed at a time interval of 3-6-15-30 days. These samples were stained with haematoxylin eosin stain, trichrome stain and with immunohistochemical stains. Results showed that in the air red blood cells could be seen for up to six days and granular deposits of Glycophorin reactive material for up to 15 days whereas no red blood cells were recognizable after 30 days. In water red cell putrefaction (or non-detection) was faster than in the air: after six days only amorphous granular deposits slightly reactive to Glycophorin could be seen. Nonetheless results showed that extravasated red blood cell residues can still be detected in skin bruises left to decompose in air and water, for up to at least 15 days in the open air and one week in water.


Asunto(s)
Aire , Eritrocitos/metabolismo , Agua Dulce , Glicoforinas/metabolismo , Cambios Post Mortem , Piel/citología , Anticuerpos Monoclonales , Contusiones/patología , Eritrocitos/patología , Patologia Forense , Glicoforinas/inmunología , Humanos , Inmunohistoquímica , Proyectos Piloto , Piel/patología , Factores de Tiempo
4.
Eur Biophys J ; 39(6): 929-34, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19343334

RESUMEN

We have made a preliminary analysis of the results about the effects on tumoral cell line (lymphoid T cell line Jurkat) induced by UVB radiation (dose of 310 mJ/cm(2)) with and without a vegetable mixture. In the present study, we have used two techniques: Fourier transform infrared spectroscopy (FTIR) and flow cytometry. FTIR spectroscopy has the potential to provide the identification of the vibrational modes of some of the major compounds (lipid, proteins and nucleic acids) without being invasive in the biomaterials. The second technique has allowed us to perform measurements of cytotoxicity and to assess the percentage of apoptosis. We already studied the induction of apoptotic process in the same cell line by UVB radiation; in particular, we looked for correspondences and correlations between FTIR spectroscopy and flow cytometry data finding three highly probable spectroscopic markers of apoptosis (Pozzi et al. in Radiat Res 168:698-705, 2007). In the present work, the results have shown significant changes in the absorbance and spectral pattern in the wavenumber protein and nucleic acids regions after the treatments.


Asunto(s)
Apoptosis/efectos de los fármacos , Células Jurkat/efectos de la radiación , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Rayos Ultravioleta , Apoptosis/fisiología , Células Cultivadas , Citometría de Flujo/métodos , Humanos , Espectrofotometría Infrarroja/métodos
5.
Eur J Neurol ; 17(9): 1178-1187, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20374278

RESUMEN

BACKGROUND AND PURPOSE: A quality of life (QoL) questionnaire for neuromuscular diseases was recently constructed and validated in the United Kingdom in a sample of adult patients with a variety of muscle disorders. Preliminary results suggested it could be a more relevant and practical measure of QoL in muscle diseases than generic health measures of QoL. The purpose of our work was: (i) To validate INQoL in Italy on a larger sample of adult patients with muscle diseases (ii) to compare INQoL to SF-36. METHODS: We have translated into Italian and applied language adaptations to the original UK INQoL version. We studied 1092 patients with different muscle disorders and performed (i) test-retest reliability (n = 80); (ii) psychometric (n = 345), known-group (n = 1092), external criterion (n = 70), and concurrent validity with SF-36 (n = 183). RESULTS: We have translated and formally validated the Italian version of INQoL confirming and extending results obtained in the United Kingdom. In addition to good results in terms of reliability, known-group and criterion validity, a comparison with the SF-36 scales showed a stronger association between INQoL total index and SF-36 physical (r = -0.72) than mental (r = -0.38) summary health indexes. When considering comparable domains of INQoL and SF-36 with respect to an objective measure of muscle strength assessment (MMRC), regression analysis showed a stronger correlation using INQoL rather than SF-36 scores. CONCLUSIONS: INQoL is recommended to assess QoL in muscle diseases because of its ability to capture physical limitations that are specifically relevant to the muscle condition.


Asunto(s)
Encuestas Epidemiológicas/normas , Debilidad Muscular/diagnóstico , Debilidad Muscular/psicología , Enfermedades Musculares/psicología , Calidad de Vida/psicología , Encuestas y Cuestionarios/normas , Adulto , Factores de Edad , Femenino , Estado de Salud , Encuestas Epidemiológicas/métodos , Humanos , Italia/epidemiología , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología , Persona de Mediana Edad , Debilidad Muscular/epidemiología , Enfermedades Musculares/epidemiología , Valor Predictivo de las Pruebas
6.
Sci Rep ; 10(1): 20008, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33203946

RESUMEN

We present estimates of the seasonal and spatial occupation by pinnipeds of the Wildlife Refuge of Ilha dos Lobos (WRIL), based on aerial photographic censuses. Twenty aerial photographic censuses were analysed between July 2010 and November 2018. To assess monthly differences in the numbers of pinnipeds in the WRIL we used a Generalized Linear Mixed Model. Spatial analysis was carried out using Kernel density analysis of the pinnipeds on a grid plotted along the WRIL. Subadult male South American sea lions (Otaria flavescens) were the most abundant pinniped in the WRIL. Potential females of this species were also recorded during half of the census. The maximum number of pinnipeds observed in the WRIL was 304 in September 2018, including an unexpected individual southern elephant seal (Mirounga leonina), and a high number of South American fur seal yearlings (Arctocephalus australis). However, there was no statistically significant difference in counts between months. In all months analysed, pinnipeds were most often found concentrated in the northern portion of the island, with the highest abundances reported in September. This study confirms the importance of the WRIL as a haulout site for pinnipeds in Brazil, recommends that land research and recreational activities occur in months when no pinnipeds are present, and encourages a regulated marine mammal-based tourism during winter and spring months.


Asunto(s)
Lobos Marinos/fisiología , Leones Marinos/fisiología , Animales , Brasil , Caniformia/fisiología , Femenino , Masculino , Phocidae/fisiología , Estaciones del Año
7.
Sci Rep ; 7(1): 5271, 2017 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-28706228

RESUMEN

An understanding of the underlying processes and comprehensive history of population growth after a harvest-driven depletion is necessary when assessing the long-term effectiveness of management and conservation strategies. The South American sea lion (SASL), Otaria flavescens, is the most conspicuous marine mammal along the South American coasts, where it has been heavily exploited. As a consequence of this exploitation, many of its populations were decimated during the early 20th century but currently show a clear recovery. The aim of this study was to assess SASL population recovery by applying a Bayesian state-space modelling framework. We were particularly interested in understanding how the population responds at low densities, how human-induced mortality interplays with natural mechanisms, and how density-dependence may regulate population growth. The observed population trajectory of SASL shows a non-linear relationship with density, recovering with a maximum increase rate of 0.055. However, 50 years after hunting cessation, the population still represents only 40% of its pre-exploitation abundance. Considering that the SASL population in this region represents approximately 72% of the species abundance within the Atlantic Ocean, the present analysis provides insights into the potential mechanisms regulating the dynamics of SASL populations across the global distributional range of the species.


Asunto(s)
Teorema de Bayes , Conservación de los Recursos Naturales , Biología Marina , Leones Marinos/crecimiento & desarrollo , Animales , Densidad de Población , Dinámica Poblacional , Crecimiento Demográfico
8.
Forensic Sci Int ; 164(2-3): 131-7, 2006 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-16466877

RESUMEN

Skeletal injuries are often strong indicators of child abuse and their detection is therefore crucial. The aim of this study was to compare the sensitivity of three diagnostic approaches, namely autopsy, traditional (conventional) radiology, and computed tomography on "battered" piglets, in order to verify the sensitivity of each method, with respect to the true number of bone fractures assessed once the piglet was skeletonised (osteological control). Four newborn cadaver piglets who had died from natural causes were severely beaten post-mortem in every district of the body. Traditional radiography, computed tomography (CT) and autopsy were performed. The piglet was then macerated until skeletonised and the number of all fractures present recorded (osteological control). On the cranium, traditional radiology revealed only 35% circa of actual fractures, autopsy detected only 31% (P<0.01 for both comparisons versus osteological control), whereas CT imaging detected all fractures actually present. For ribs, radiology detected only 47% of all fractures present, and autopsy 65% circa (P>0.05 for both comparisons versus osteological control), while CT scans detected 34% (P<0.01). In suspected cases of fatal child abuse, we suggest that the bones of specific districts be directly analysed either at autopsy or by collecting specific diagnostic sites, such as parts of the rib cage, and subjecting them to maceration. The removed areas could be replaced with artificial material for cosmetic purposes. The authors stress the importance of combined radiological, CT scan, autopsy and osteological survey in the detection of perimortem bone fractures.


Asunto(s)
Autopsia , Maltrato a los Niños/diagnóstico , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/patología , Modelos Animales , Tomografía Computarizada por Rayos X , Animales , Niño , Extremidades/diagnóstico por imagen , Extremidades/lesiones , Extremidades/patología , Medicina Legal , Humanos , Costillas/diagnóstico por imagen , Costillas/lesiones , Costillas/patología , Cráneo/diagnóstico por imagen , Cráneo/lesiones , Cráneo/patología , Porcinos
9.
Cancer Res ; 50(14): 4291-4, 1990 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-1694719

RESUMEN

Selective elimination of multidrug resistance-positive cells (LoVo/Dx) was obtained by using the monoclonal antibody MRK 16, which recognizes a surface epitope of the Mr 170,000 glycoprotein, and a sheep anti-mouse immunoglobulin antibody, conjugated to the ribosome-inactivating protein saporin 6. The killing was greatly decreased or even abolished by adding the monoclonal antibody at a 100-fold concentration. Both the MRK 16 and anti-mouse saporin 6 conjugate did not show any killing activity when they were used separately. In cell suspensions composed of 90% normal bone marrow cells and 10% multidrug resistance-positive cells, the monoclonal antibody MRK 16 followed by the anti-mouse immunotoxin caused the elimination of 99% multidrug resistance-positive cells, as revealed by immunofluorescence and immunocytochemistry as well as by a clonal assay. Human normal hematopoietic precursors (granulomonocytic colony-forming units, erythroid burst-forming units, and multipotent granulomonocytic, erythroid, and megakaryocytic-forming units) were not affected by the MRK 16 plus immunotoxin treatment. This technique might be suitable for ex vivo bone purging in an appropriate clinical setting, such as autologous bone marrow transplantation.


Asunto(s)
Anticuerpos Monoclonales , Antineoplásicos Fitogénicos/farmacología , Células de la Médula Ósea , Resistencia a Medicamentos , Inmunotoxinas/farmacología , Glicoproteínas de Membrana/inmunología , N-Glicosil Hidrolasas , Proteínas de Plantas/farmacología , Médula Ósea/efectos de los fármacos , Línea Celular , Neoplasias del Colon , Ensayo de Unidades Formadoras de Colonias , Doxorrubicina/farmacología , Epítopos/análisis , Humanos , Peso Molecular , Proteínas Inactivadoras de Ribosomas Tipo 1 , Saporinas , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/efectos de los fármacos , Ensayo de Tumor de Célula Madre
10.
Anat Histol Embryol ; 45(5): 405-8, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26497953

RESUMEN

We present the first record and description of an anembryonic gestation in a wild South America sea lion, Otaria flavescens (Carnivora, Pinniped). This is the first report of an anembryonic gestation in a wild marine mammal species. This description furthers the knowledge of general aspects of the reproduction of an otariid species, which presents the particularities of delayed implantation and polygynic breeding system, and adds information on a reproductive abnormality in marine mammals.


Asunto(s)
Implantación del Embrión/fisiología , Complicaciones del Embarazo/patología , Leones Marinos/embriología , Mortinato/veterinaria , Animales , Femenino , Embarazo , Reproducción , América del Sur
11.
J Musculoskelet Neuronal Interact ; 5(2): 174-81, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15951635

RESUMEN

Thirty male adult Wistar rats (300-/+10 g body weight) underwent either 5/6 nephrectomy (Nx, n=20) or sham operation (SHAM, n=10) to determine olpadronate effects in an experimental model of uremic bone disease. For a 38-day period, 10 rats received olpadronate (16microg/100g bw) once a week (Nx+OPD) and the other vehicle (Nx). SHAM received vehicle. At baseline, treatment onset (t=7 days) and end of study (t=45 days) calcium, phosphorus, creatinine, bone alkaline phosphatase (b-ALP) and deoxypyridinoline crosslinks (DPyr) were determined. At t=0 and t=45 bone mineral density (BMD) was measured by DXA. At t=45 the right tibia was removed for bone histology. There were no differences in serum calcium. Phosphorus increased in Nx and Nx+OPD compared to SHAM (p

Asunto(s)
Enfermedades Óseas Metabólicas/tratamiento farmacológico , Resorción Ósea/metabolismo , Huesos/efectos de los fármacos , Difosfonatos/uso terapéutico , Uremia/complicaciones , Fosfatasa Alcalina/sangre , Fosfatasa Alcalina/efectos de los fármacos , Aminoácidos , Animales , Densidad Ósea/efectos de los fármacos , Enfermedades Óseas Metabólicas/etiología , Calcio/sangre , Calcio/orina , Creatinina/sangre , Creatinina/orina , Modelos Animales de Enfermedad , Riñón/cirugía , Masculino , Fósforo/sangre , Ratas
12.
J Anim Sci ; 93(2): 758-66, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26020756

RESUMEN

To attain a good level of animal welfare, pigs require a sufficient environmental illumination. Therefore, minimum levels for light duration and light intensity have been set up by the European legislation (Directive 2008/120). An experimental trial was designed to determine whether an increased duration of the photophase (up to 16 h of light per day) could modify the behavior, productive parameters, and meat and ham quality of Italian heavy pigs. Forty crossbred (Large White × Landrace) castrated males pigs (26 kg initial average BW) intended for Protected Designation of Origin (according to European Union Regulation 1151/2012, ) dry-cured ham production were raised according to Parma ham production rules up to the weight of 160 kg. Pigs were homogeneously allotted to 2 experimental groups, each comprising 20 pigs. The short photoperiod (SP) group received the minimum mandatory number of hours of light per day (corresponding to 8 h/d), whereas the long photoperiod (LP) group was subjected 16 h of light per day during the whole production cycle. Light intensity was maintained at 40 lux (i.e., the minimum mandatory level) for both the experimental groups. Growth and slaughtering parameters, carcass traits, fatty acid composition, meat and dry-cured ham quality, and animal behavior were assessed. Pigs in the LP group showed a greater live weight and carcass weight compared to the SP group ( = 0.005 and = 0.007, respectively). Similarly, hams obtained from the LP group were significantly heavier and their weight losses during the dry-curing period were reduced ( < 0.01) when compared to the SP group. No significant differences were detected between the experimental groups as concerns meat and ham quality or fatty acid composition of the subcutaneous fat. Pigs in the LP group spent more time resting and less time pseudo-rooting ( < 0.01). Our results indicate that, given an appropriate dark period for animal rest, an increased duration of the photoperiod, even at the lower mandatory light intensity level, can favorably affect growth parameters of heavy pigs without any negative effect on animal behavior, carcass traits, or meat or long-cured ham quality. Therefore, rearing pigs in semidarkness should be considered as a baseless practice, contrary to animal welfare.


Asunto(s)
Conducta Animal/fisiología , Peso Corporal/fisiología , Industria de Alimentos/normas , Carne/normas , Fotoperiodo , Porcinos/crecimiento & desarrollo , Porcinos/fisiología , Bienestar del Animal , Animales , Composición Corporal/fisiología , Ácidos Grasos/análisis , Masculino , Fenotipo , Control de Calidad , Descanso/fisiología , Grasa Subcutánea/química , Factores de Tiempo
13.
Forensic Sci Int ; 250: e1-2, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25770023

RESUMEN

The need to identify the dead - an issue of paramount importance for the forensic sciences - and its importance for humanitarian, administrative, judicial and other purposes are universal values enshrined by domestic and international law. However, for hundreds of men, women and children, migrants, who die every year in their attempt to cross the Mediterranean Sea to reach Europe this fundamental right remains unfulfilled. In order to address and bring solutions to this tragedy the International Committee of the Red Cross (ICRC) carried out an assessment in 2012 and 2013 across European Mediterranean countries affected by irregular immigration across the sea (Italy, Greece, Malta, Portugal, France, Spain). An international meeting in 2013 among Southern European countries led to recommendations which should serve as a road-map for action. They are already guiding activities of the ICRC and other participant institutions. The Council of Europe, which endorsed the recommendations, has since stepped up its efforts to prevent and resolve the humanitarian consequences of migration, including the unidentified dead. Among other things it has called on its Member States to "set up a proper system of data collection of the mortal remains of people who lose their lives in the Mediterranean and make it swiftly accessible to relatives".


Asunto(s)
Emigrantes e Inmigrantes , Ciencias Forenses , Cooperación Internacional , Humanos , Mar Mediterráneo , Cruz Roja
14.
Eur J Cancer ; 29A(11): 1560-5, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8217363

RESUMEN

The purpose of this study was to examine the cytotoxicity and cardiotoxicity of the new doxorubicin derivative, 3'-deamino-3'-(2-methoxy-4-morpholinyl)-doxorubicin (FEC 23762). The concentration of FCE 23762 that resulted in a 50% reduction in colony formation of DU 145, COLO 320DM, A549 and A2780 human cancer cell lines ranged from 1.1 and 3.2 nmol/l and was 3-9 times as low as doxorubicin. In the isolated perfused rat hearts, doxorubicin 10(-5) mol/l induced a significant prolongation of S alpha T segment and Q-Fmax interval, and reduction in dF/dtmax and coronary flow while only FCE 23762 10(-5) mol/l induced a widening of QRS complex. Anaesthetised rats given a single intravenous (i.v.) dose of doxorubicin 10 mg/kg showed significant changes in both ECG (S alpha T segment and QRS complex enlargement) and haemodynamic parameters (increase in mean arterial blood pressure and reduction in systemic arterial dP/dtmax), while animals given FCE 23762 (0.1 and 0.3 mg/kg) had a significant increase in QRS complex duration after the highest dose. In the chronic cardiotoxicity study animals receiving FCE 23762 (0.03 mg/kg i.v. once a week for 3 weeks) did not show any significant alteration of ECG and minor changes of cardiac histological picture; by contrast doxorubicin (3 mg/kg i.v. once a week for 3 weeks) induced a severe cardiomyopathy, characterised by progressive widening of S alpha T segment, increase in T wave and histological damage consisting of vacuolations and loss of myofibrils. These results indicate that FCE 23762 is more active in vitro than doxorubicin and markedly less cardiotoxic in vivo at the doses used in the present study.


Asunto(s)
Doxorrubicina/análogos & derivados , Corazón/efectos de los fármacos , Células Tumorales Cultivadas/efectos de los fármacos , Animales , Cardiomiopatías/inducido químicamente , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Doxorrubicina/toxicidad , Electrocardiografía/efectos de los fármacos , Femenino , Humanos , Ratas , Ratas Wistar , Ensayo de Tumor de Célula Madre
15.
J Med Chem ; 27(10): 1295-9, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6592359

RESUMEN

L-Alanosine [3-(hydroxynitrosoamino)-L-alanine] is an antitumor antibiotic that at the present is undergoing phase II clinical trials. Its mode of action as well as its metabolism has been extensively studied, and the metabolite N-[(5-amino-1-beta-D-ribofuranosyl-1H-imidazol-4-yl)carbonyl]-3- (hydroxynitrosoamino)-L-alanine ribonucleotide (L-alanosine AICOR) proved to be an extremely potent inhibitor of de novo purine biosynthesis and is thus primarily responsible for the antitumor activity of the drug. The synthesis of the corresponding ribonucleoside, i.e., N-[(5-amino-1-beta-D-ribofuranosyl-1H-imidazol-4-yl)carbonyl]-3- (hydroxynitrosamino)-L-alanine ribonucleoside (L-alanosine AICO ribonucleoside), was accomplished by condensation of a suitably protected derivative of L-alanosine with N-succinimidyl-5-amino-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)-1H-im idazole-4-carboxylate followed by the removal of the protective groups. The biological activity of L-alanosine AICO ribonucleoside was tested in vitro on whole tumor cells and on the isolated enzyme adenylosuccinate synthetase and in vivo on murine experimental leukemia. The compound was found to be inactive in these tests.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , Ribonucleótidos/síntesis química , División Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Humanos , Indicadores y Reactivos , Leucemia Mieloide Aguda , Espectroscopía de Resonancia Magnética , Ribonucleótidos/toxicidad , Espectrofotometría Infrarroja
16.
Biochem Pharmacol ; 47(2): 295-302, 1994 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-7508230

RESUMEN

Tumor-induced neoangiogenesis is an essential event for solid tumor growth. Therefore, a compound able to block angiogenesis-promoting factors could have antitumor activity. The polysulfonated naphthylurea suramin is hypothesized to have this mode of action. A series of sulfonated distamycin A derivatives have been synthesized with the objective of identifying novel compounds able to complex basic fibroblastic growth factor (bFGF) and other factors involved in tumour angiogenesis, and consequently to block the angiogenic process. These new compounds have been characterized for their ability to inhibit bFGF binding, in vivo bFGF-induced angiogenesis and neovascularization of the chorioallantoic membrane, in comparison with suramin. The two most active compounds, FCE 26644 [7,7'-(carbonyl-bis(imino-N-methyl-4,2-pyrrolecarbonyl-imino(N-met hyl-4,2- pyrrole)carbonylimino))-bis(1,3-naphthalenedisulfonic acid)] and FCE 27164 [7,7'-(carbonyl-bis(imino-N-methyl-4,2-pyrrolecarbonyl-imino(N-met hyl-4,2- pyrrole) carbonylimino)-bis (1,3,5-naphthalenetrisulfonic acid)] have been selected for extended evaluation. Both compounds are active in inhibiting platelet-derived growth factor beta (PDGF beta) and interleukin-1 beta binding. Two different assays have been performed to study their mode of action: the sequential binding assay on bFGF and PDGF receptors and the bFGF-induced tyrosine phosphorylation assay. The results of the two assays are in agreement and indicate that no activity is observed if FCE 26644, FCE 27164 and suramin are administered as pretreatment, when a direct interaction of the compounds with bFGF and PDGF receptors is required. Conversely, inhibitory activity is observed when the compounds are allowed to form complexes with the growth factors themselves.


Asunto(s)
Distamicinas/química , Distamicinas/farmacología , Factor 2 de Crecimiento de Fibroblastos/química , Ácidos Sulfónicos/farmacología , Células 3T3 , Animales , Unión Competitiva , Distamicinas/síntesis química , Factor 2 de Crecimiento de Fibroblastos/antagonistas & inhibidores , Ratones , Ratones Endogámicos BALB C , Neovascularización Patológica/prevención & control , Fosforilación , Relación Estructura-Actividad , Suramina/farmacología , Tirosina/metabolismo
17.
Biochem Pharmacol ; 37(23): 4423-31, 1988 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-3202888

RESUMEN

The mechanisms of resistance to doxorubicin (DX) were investigated using a human colon adenocarcinoma cell line (LoVo) and a subline approximately 30 times less sensitive to doxorubicin. LoVo and LoVo/DX were similar in terms of DNA and protein content, cell volume, duration of S phase and the generation time, and proportion of cycling cells. LoVo/DX showed cross-resistance to other anthracyclines, to vinca alkaloids, epipodophyllotoxin derivatives, 4'-(9-acridinylamino-methanesulfon-m-aniside) and actinomycin D. LoVo/DX was equally sensitive to melphalan and showed collateral sensitivity to cis-platinum and 1-beta-D-arabinofuranosylcytosine. On exposing LoVo and LoVo/DX to 1.25 and 40 micrograms/ml DX respectively, for 4 hr, similar DX intracellular concentrations were reached in the two cell lines. In these treatment conditions protein associated DNA-single strand breaks or DNA-double strand breaks, assessed by alkaline elution methods were only slightly less in LoVo/DX than in LoVo cells. In LoVo/DX cells, however, DNA breaks disappeared very quickly after drug removal whereas they persisted longer in LoVo cells. This persistance is probably related to the much slower DX efflux from LoVo than LoVo/DX. When verapamil was combined with DX it inhibited the rapid DX efflux from LoVo/DX and reversed the resistance in this cell line, but it had no significant activity on LoVo cells. Verapamil also increased DX-induced DNA-single strand breaks and DNA-double strand breaks in LoVo/DX cells, but not in LoVo cells.


Asunto(s)
Adenocarcinoma/patología , Neoplasias del Colon/patología , Daño del ADN , ADN de Neoplasias/efectos de los fármacos , Doxorrubicina/farmacología , Adenocarcinoma/genética , Línea Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cisplatino/farmacología , Neoplasias del Colon/genética , Citarabina/farmacología , Dactinomicina/farmacología , Resistencia a Medicamentos , Citometría de Flujo , Humanos , Verapamilo/farmacología
18.
EXS ; 61: 455-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1377571

RESUMEN

The successful growth of tumors is dependent on the process of vascularization elicited by the tumor itself. As confirmed by many authors, there is a correlation between the presence of factors that stimulate tumor growth and angiogenesis. One of the approaches we have explored to control angiogenesis has been to synthesize compounds able to complex growth factors. A number of sulphonated derivatives of distamycin A were found active in inhibiting the binding of bFGF and PDGF beta on Swiss 3T3 cells with ID50 values ranging between 142-587 microM for bFGF and 28-79 microM for PDGF beta. The effect of these new derivatives in inhibiting angiogenesis was initially explored in the chorioallantoic membrane assay. It was observed that the selected compounds were active in this model system at the concentration of 350 nm/pellet. These new molecules present low or no cytotoxic activity on M5076 murine reticulosarcoma cells, the ID50 values being higher than 60 microM after 72 h continuous exposure in vitro.


Asunto(s)
Capilares/patología , Distamicinas/farmacología , Ácidos Sulfónicos/farmacología , Células 3T3 , Animales , Capilares/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Distamicinas/síntesis química , Doxorrubicina/farmacología , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Linfoma de Células B Grandes Difuso , Ratones , Neovascularización Patológica/patología , Neovascularización Patológica/prevención & control , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptores de Superficie Celular/efectos de los fármacos , Receptores de Superficie Celular/metabolismo , Receptores de Factores de Crecimiento de Fibroblastos , Receptores del Factor de Crecimiento Derivado de Plaquetas , Relación Estructura-Actividad , Ácidos Sulfónicos/síntesis química , Células Tumorales Cultivadas
19.
EXS ; 61: 459-62, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1377572

RESUMEN

Solid tumor growth can be modulated through inhibition of vascularization elicited by angiogenic factors. With the objective to complex these factors, new derivatives of distamycin A were synthesized and evaluated in vitro [1] and in vivo for their ability, after i.v. administration, to inhibit bFGF-induced vascularization and the growth of M5076 murine reticulosarcoma implanted i.m. The tested compounds were able to block angiogenesis with inhibition values ranging between 70-100%. Moreover, they were found to be capable of inducing tumor inhibition with values ranging between 40% and 95% at non-toxic doses.


Asunto(s)
Antineoplásicos/uso terapéutico , Distamicinas/uso terapéutico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Neovascularización Patológica/prevención & control , Animales , Colágeno , Femenino , Factor 2 de Crecimiento de Fibroblastos/farmacología , Linfoma de Células B Grandes Difuso/patología , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Neovascularización Patológica/patología , Prótesis e Implantes , Relación Estructura-Actividad , Ácidos Sulfónicos/uso terapéutico
20.
Invest Radiol ; 23 Suppl 1: S267-70, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3198360

RESUMEN

Compounds containing mobile protons can act as contrast agents by increasing the value of the term (1/12 - 1/11). The efficiency of this method is markedly pH- and field-dependent. There are many such compounds allowing a choice to be made based on the characteristics of the tissue or organ, magnetic field strength, and solution pH levels. The properties of some of these chemicals have been investigated at different magnetic field strength and solution pH levels. The authors report herein the properties of iopamidol a well-known x-ray contrast agent, and stress its potential effect as an MRI contrast agent. The influence on the T2 decrease of the chemical shift separation delta omega (in frequency units) between water and exchangeable proton of the contrast agent may be increased by adding suitable shift reagents which interact with basic sites close to the protons involved in the chemical exchange.


Asunto(s)
Medios de Contraste , Yopamidol , Imagen por Resonancia Magnética , Animales , Humanos , Concentración de Iones de Hidrógeno , Agua
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