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1.
Toxicol Appl Pharmacol ; 266(2): 214-23, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23142466

RESUMO

The toxicodynamic relationship between the number and size of pulmonary microemboli resulting from uniformly sized, rigid polystyrene microparticles (MPs) administered intravenously and their potential effects on pulmonary gas exchange were investigated. CD-1 male mice (6-8 weeks) were intravenously administered 10, 25 and 45 µm diameter MPs. Oxygen hemoglobin saturation in the blood (SpO(2)) was measured non-invasively using a pulse oximeter while varying inhaled oxygen concentration (F(I)O(2)). The resulting data were fit to a physiologically based non-linear mathematical model that estimates 2 parameters: ventilation-perfusion ratio (V(A)/Q) and shunt (percentage of deoxygenated blood returning to systemic circulation). The number of MPs administered prior to a statistically significant reduction in normalized V(A)/Q was dependent on particle size. MP doses that resulted in a significant reduction in normalized V(A)/Q one day post-treatment were 4000, 40,000 and 550,000 MPs/g for 45, 25 and 10 µm MPs, respectively. The model estimated V(A)/Q and shunt returned to baseline levels 7 days post-treatment. Measuring SpO(2) alone was not sufficient to observe changes in gas exchange; however, when combined with model-derived V(A)/Q and shunt early reversible toxicity from pulmonary microemboli was detected suggesting that the model and physical measurements are both required for assessing toxicity. Moreover, it appears that the MP load required to alter gas exchange in a mouse prior to lethality is significantly higher than the anticipated required MP dose for effective drug delivery. Overall, the current results indicate that the microemboli-based approach for targeted pulmonary drug delivery is potentially safe and should be further explored.


Assuntos
Sistemas de Liberação de Medicamentos , Microesferas , Poliestirenos/química , Embolia Pulmonar/metabolismo , Troca Gasosa Pulmonar/efeitos dos fármacos , Animais , Estudos de Viabilidade , Pulmão/metabolismo , Masculino , Camundongos , Modelos Teóricos , Dinâmica não Linear , Oximetria , Oxigênio/metabolismo , Tamanho da Partícula
2.
Commun Agric Appl Biol Sci ; 75(3): 341-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21539252

RESUMO

Following the EPPO guidelines and Principles of Good Experimental Practice (GEP), an experiment was realised in autumn 2008 for evaluating the efficacy of Oberon applied by foliar treatments to contain infestations of mites and whiteflies on Capsicum annuum L.. Two different dosages of OBERON (a.i. Spiromesifen)--45 and 60 g/hl--were compared with a unique dosage of two commercial formulates: VERTIMEC (a.i. Abamectine, Syngenta Crop Protection), 60 g/hl, and MAGISTER (a.i. Fenazaquin, Dow AgroSciences), 110 g/hl. Oberon resulted very effective in the control of phytopathogenic mites at both doses of 45 and 60 g/hl. Its effectiveness demonstrated to be remarkable for approximately one month after application. By contrast, Vertimec and Magister have proven their effectiveness for a much lower period of time (about the first 15 days post application). About the efficacy against whiteflies, even 36 days after the foliar application Oberon showed a strong containment of the populations of aleurodides. There were no phenomena of phytotoxicity nor on leaves nor on flowers and fruits, in none of the treatments. About the phytotoxicity on the useful entomofauna, the assessments made on the different treatments have highlighted the lack of harmful effects on predators and on parasitoids of insects and mites.


Assuntos
Acaricidas/farmacologia , Capsicum/parasitologia , Hemípteros/efeitos dos fármacos , Inseticidas/farmacologia , Ácaros/efeitos dos fármacos , Compostos de Espiro/farmacologia , Animais , Fatores de Tempo
3.
J Phys Condens Matter ; 32(8): 085701, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31675741

RESUMO

Glass-forming systems approaching their glass transition exhibit universal correlations between picosecond vibrational dynamics and long-time structural relaxation, which can be described by the same master curve in the bulk or confined conditions. In this work, we study at a fundamental level the effects of the reduction of spatial dimensionality on this phenomenon. We perform molecular dynamics simulations of a metallic glass-formers in two dimensions (2D). We show that in the supercooled regime particle localization in the cage and structural relaxation are blurred by long-wavelength fluctuations specific to low-dimensional systems. Once these effects are properly removed, we demonstrate that the fast dynamics and slow relaxation comply, without any adjustment, with same scaling between the structural relaxation time and the Debye-Waller factor, originally observed in three-dimensions (3D).

4.
J Chem Phys ; 131(3): 034505, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19624207

RESUMO

A multifrequency electron paramagnetic resonance (EPR) investigation of Nd(3+) impurities in PbWO(4) single-crystals at the conventional microwave frequency (MF) 9.43 GHz, and at the 95, 190, and 285 GHz high frequencies was carried out. The resulting spectra are well described at all frequencies by an axial spin-Hamiltonian corresponding to an effective electron spin of one-half and to a tetragonal symmetry. For the magnetic field along the tetragonal axis, the g(parallel)-factor and the hyperfine constant A(parallel) of the lowest doublet of the ground multiplet decreases with frequency increase. For the magnetic field perpendicular to the tetragonal axis, the g(perpendicular)-factor exhibits a small azimuthal angular dependence that increases with increasing the frequency due to the S(4) site symmetry. The azimuthal angular dependence allows to clearly distinguish between different local axial symmetries. These properties are interpreted as high field/frequency (HF) effects associated with the mixing by the large Zeeman interaction of some of the upper-lying doublets of the ground multiplet into the lowest-lying doublet states. We show that from the combined analysis of the multifrequency MF- and HF-EPR spectra and of the optical data, an accurate description of the ground multiplet of the Kramers rare earth ions in solid matrices can be derived.


Assuntos
Neodímio/química , Teoria Quântica , Compostos de Tungstênio/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Íons/química , Micro-Ondas
5.
J Chem Phys ; 129(8): 081102, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-19044810

RESUMO

Exploiting the high angular resolution of high field electron paramagnetic resonance measured at 95, 190, and 285 GHz we determine the rotational nonergodicity parameter of different probe molecules in the glass former o-terphenyl and polybutadiene in a model-independent way. Our results clearly show a characteristic change in the temperature of the nonergodicity parameter proving a rather sharp dynamic crossover in both systems, in contrast to previous results from other techniques.

7.
Biol Psychiatry ; 29(8): 789-98, 1991 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1675894

RESUMO

Binding parameters of (-)-iodopindolol to beta 2-adrenoceptors were determined on intact mononuclear cells in 41 untreated patients with different DSM-III subtypes of depression. Both maximal beta-receptor density (Bmax) and dissociation constant (Kd) were not significantly different between control and all depressed subjects. However, Bmax was significantly decreased in unipolar patients as compared to controls (p less than 0.001) whereas no significant difference was found in bipolar or dysthymic patients. In unipolar patients, a very strong association was found between Bmax values and the severity of the depression as assessed by the Hamilton Depression Rating Scale score (r = -0.75; p less than 0.005). This correlation was also highly significant in the entire depressed population (r = -0.58; p less than 0.0009). These results suggest that the lower number of beta-adrenoceptors in intact leukocyte cells of depressed patients is related to the depression severity.


Assuntos
Antagonistas Adrenérgicos beta , Transtorno Bipolar/sangue , Transtorno Depressivo/sangue , Monócitos/metabolismo , Pindolol/análogos & derivados , Receptores Adrenérgicos beta/fisiologia , Adulto , Idoso , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pindolol/farmacocinética , Escalas de Graduação Psiquiátrica , Estações do Ano
8.
J Magn Reson ; 143(1): 88-94, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10698649

RESUMO

High-field/high frequency EPR spectroscopy measurements are shown. Experiments were carried out at 240- and 316-GHz frequencies. The employed apparatus uses a novel combination of far infrared molecular lasers and of probehead exploiting dielectric resonators working in the whispering gallery modes. This approach constitutes a relatively simple method of multifrequency EPR spectroscopy and opens appealing perspectives in high-sensitivity EPR spectroscopy up to the THz regime.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Espectroscopia de Ressonância de Spin Eletrônica/instrumentação
9.
Clin Chim Acta ; 298(1-2): 121-33, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10876009

RESUMO

We performed prenatal diagnoses for cystic fibrosis in 32 high risk (1:4) couples (including a dizygotic pregnancy). Chorionic villi sampling did not cause abortion or fetal malformation in any case. The preliminary analysis of 9 short tandem repeats always excluded maternal contamination of the DNA extracted from chorionic villi and confirmed paternity. Twenty-two prenatal diagnoses were made by direct analysis of the mutations. In seven cases diagnosis was made by the analysis of intragenic polymorphisms; in three cases, we analyzed two extragenic polymorphisms. The prenatal diagnosis (including genetic counselling) was completed within 24 h from the sampling. Seven prenatal diagnoses revealed an affected fetus; all couples opted for therapeutic abortion. In 17 cases the fetus was heterozygote, and in seven cases it was non carrier of mutated alleles. In the twin pregnancy, mutations were DeltaF508/N1303K. Direct analysis of the DNA extracted from the two independent samples of chorionic villi revealed one fetus non carrier of mutated alleles and the other a carrier of the N1303K mutation. Analysis of the HPRT locus predicted both the fetuses as males. Furthermore, the genotype of each fetus was defined after birth. The prenatal diagnosis with chorionic villi sampling plays a key role in the prevention of cystic fibrosis. The laboratories must be equipped for both the direct analysis of mutations and for the analysis of a large number of polymorphisms. The preliminary analysis of short tandem repeats is recommended both to exclude maternal contamination and to confirm parentage.


Assuntos
Amostra da Vilosidade Coriônica , Fibrose Cística/diagnóstico , Doenças em Gêmeos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Paternidade , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez , Gêmeos Dizigóticos
10.
Anticancer Res ; 19(3A): 1909-18, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10470135

RESUMO

In spite of extensive investigation, the mechanism for cell cytotoxicity of the anthracycline antitumor drug adriamycin (ADR) has not yet been completely understood but the nature of the cytotoxic effects of this drug is generally related to its interaction with nuclear components, such as DNA and topoisomerase II. In a previous paper, we studied, using Confocal Laser Scanning Microscopy (CLSM), the localization of ADR and its glutathione (GSH)-conjugate (ADRIGLU), obtained by the anaerobic reaction of the parent anthracycline with reduced GSH, in drug-sensitive and in multidrug resistant (MDR) cells. In all drug-sensitive lines used, ADR was mostly located in the nuclei, while its GSH-conjugate was found only in the cytoplasm, predominantly in the Golgi region. In this study we examined the morphological changes induced by ADR or its GSH-conjugated adduct (ADRIGLU) treatments in TVM-A12 (clone 2) melanoma and K562 erythroleukemia human cell lines, correlated to programmed cell death (apoptosis). We observed that ADR-induced apoptosis in both cell lines tested after 5 h treatment: CLSM and Scanning Electron Microscopy (SEM) showed cell shrinkage, fragmentation and condensation of nuclear chromatin, cell surface blebbing and cytoplasmic vacuolization. On the contrary, ADRIGLU-induced fragmentation and condensation of nuclear chromatin, typical of apoptosis, only after 48-72 h treatment. Cytoflourimetric assay by propidium iodide staining confirmed the data obtained by CLSM and SEM. Our data suggest that apoptosis activation by anthracycline antitumor drugs is induced not only by direct interaction with nuclear components but also with cytoplasmic compartments.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Doxorrubicina/farmacologia , Glutationa/farmacologia , Antibióticos Antineoplásicos/toxicidade , Núcleo Celular/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , DNA de Neoplasias/análise , Doxorrubicina/toxicidade , Citometria de Fluxo , Humanos , Células K562/efeitos dos fármacos , Melanoma/patologia , Microscopia Confocal , Microscopia de Fluorescência , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos
11.
Cutis ; 59(3): 119-22, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9071549

RESUMO

We report the case of an alcoholic patient, 41 years old, with negative results of serologic tests for human immunodeficiency virus (HIV) with a perianal Buschke-Löwenstein tumor present for eight years and exceptionally large. The patient's cell-mediated immunity was evaluated by two functional tests: the Multitest IMC (Institut Mérieux, Lyon) and the dinitrochlorobenzene (DNCB) test. The patient neither responded to any Multitest antigens nor was sensitized by DNCB. We consider that the immune short-age in this patient could influence the appearance of the Buschke-Löwenstein tumor.


Assuntos
Condiloma Acuminado , Adulto , Doenças do Ânus/diagnóstico , Doenças do Ânus/imunologia , Doenças do Ânus/patologia , Doenças do Ânus/terapia , Condiloma Acuminado/diagnóstico , Condiloma Acuminado/imunologia , Condiloma Acuminado/patologia , Condiloma Acuminado/terapia , Humanos , Imunidade Celular , Masculino , Papillomaviridae , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/terapia , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/terapia
13.
J Chem Phys ; 123(17): 174906, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16375568

RESUMO

The reorientation of one small paramagnetic molecule (spin probe) in glassy polystyrene (PS) is studied by high-field electron paramagnetic resonance spectroscopy at two different Larmor frequencies (190 and 285 GHz). Two different regimes separated by a crossover region are evidenced. Below 180 K the rotational times are nearly temperature independent with no apparent distribution. In the temperature range of 180-220 K a large increase of the rotational mobility is observed with the widening of the distribution of correlation times which exhibits two components: (i) a deltalike, temperature-independent component representing the fraction of spin probes w which persist in the low-temperature dynamics; (ii) a strongly temperature-dependent component, to be described by a power distribution, representing the fraction of spin probes 1-w undergoing activated motion over an exponential distribution of barrier heights g(E). Above 180 K a steep decrease of w is evidenced. The shape and the width of g(E) do not differ from the reported ones for PS within the errors. For the first time the large increase of the rotational mobility of the spin probe at 180 K is ascribed to the onset of the fast dynamics detected by neutron scattering at T(f)=175+/-25 K.

14.
Magn Reson Chem ; 43 Spec no.: S215-20, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16235220

RESUMO

High-field electron paramagnetic resonance (HF-EPR) spectroscopy was used to investigate the unusual temperature and frequency dependence of the powder spectrum of the Gd(HBPz3)2 tropolonate complex (GdTrp). A new type of H/T effect is evidenced. This effect is interpreted in terms of the formation of spin projection states delocalized and quasidelocalized along linear chains of Gd3+ ions in high magnetic fields due to the competition between the weak dipole and exchange spin-spin interaction and the particular structure of the molecular complex. The number of ions in the chain depends strongly on the orientation of the magnetic field and on the relaxation processes.

15.
An Esp Pediatr ; 11(3): 237-40, 1978 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-208438

RESUMO

A case of dominant polysyndactily with double pyeloureteral system is described and the relationships between anomalies of the limb and of the urologic system are discussed, with particular emphasis in the acro-renal syndrome.


Assuntos
Anormalidades Múltiplas/genética , Pelve Renal/anormalidades , Sindactilia/genética , Ureter/anormalidades , Genes Dominantes , Humanos , Lactente , Rim/diagnóstico por imagem , Masculino , Radiografia , Sindactilia/diagnóstico por imagem , Ureter/diagnóstico por imagem
16.
Chemistry ; 6(24): 4580-6, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11192091

RESUMO

The synthesis and characterisation of an asymmetric dinuclear gadolinium(III) semiquinonato complex, namely [Gd2(HBPz3)2(dtbsq)4] CHCl3 (1; HBPz3 = hydrotris(pyrazolyl)borate, dtbsq = 3,5-di-tert-butyl-O-semiquinone), is reported. The crystal structure of 1 was determined at room temperature. It crystallises in the triclinic system P1, with a = 16.735(5) A, b = 17.705(5) A, c = 19.553(5) A, alpha = 99.680(5) degrees, beta = 109.960(5), gamma = 107.350(5) degrees, Z = 2 and R = 9.96. The structure of 1 consists of a dinuclear asymmetric unit in which the two gadolinium(III) ions have coordination numbers of eight and nine. Three of the dioxolene molecules act as asymmetric bridging ligands, while the fourth molecule behaves as a bidentate ligand towards a single metal ion. The magnetic properties of 1 were investigated by means of susceptibility measurements and high-field electron paramagnetic resonance (HF-EPR) spectroscopy. They revealed an S = 0 ground spin state with excited states of higher spin very close in energy and a small negative zero-field splitting with a transverse anisotropy term for a S = 7 state.

17.
Folia Primatol (Basel) ; 34(3-4): 278-85, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7216005

RESUMO

We describe the G, Q and C banding patterns and the localization of the nucleolar organizing regions in the chromosomes of Cercopithecus petaurista and compare them to those of other primate species.


Assuntos
Cercopithecus/genética , Bandeamento Cromossômico , Primatas/genética , Animais , Diploide , Feminino , Humanos , Macaca/genética , Masculino , Papio/genética
18.
N Engl J Med ; 292(22): 1156-9, 1975 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-1173192

RESUMO

We studied 166 hospitalized male patients to determine the clinical importance of tolerance-test-determined "lactose intolerance," assumed to affect most of the world's adults. Abnormal lactose tolerance tests were found in 81% of 98 blacks, 12% of 59 whites of Scandinavian or Northwestern European extraction, and three of nine non-European whites. Seventy-two per cent of the "lactose-intolerant" subjects had previously realized that milk drinking could induce abdominal and bowel symptoms. Two hundred and forty milliliters of low-fat milk produced gaseousness or cramps in 59% of 44 "lactose-intolerant" men, and 68% were symptomatic with the equivalent amount of lactose. None of 18 "lactose-tolerant" men noted symptoms with milk or lactose. Refusal to drink 240 ml of low-fat milk served with meals correlated significantly with "lactose-intolerance": 31.4% versus 12.9% among "lactose-tolerant" patients. "Lactose intolerance" is common in adults and is a clinically relevant problem.


Assuntos
Intolerância à Lactose/epidemiologia , Leite/efeitos adversos , Adulto , Idoso , Animais , População Negra , Carboidratos/efeitos adversos , Dieta , Etnicidade , Comportamento Alimentar , Hipersensibilidade Alimentar/diagnóstico , Gastroenteropatias/etiologia , Humanos , Intolerância à Lactose/diagnóstico , Teste de Tolerância a Lactose , Síndromes de Malabsorção/etiologia , Masculino , Maryland , Pessoa de Meia-Idade , População Branca
19.
J Med Genet ; 33(1): 73-6, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8825054

RESUMO

We describe the clinical features of seven cystic fibrosis patients from southern Italy who bear rare genotypes: (1) a patient homozygous for the 2183 AA-->G mutation who was affected by a very early pulmonary form of cystic fibrosis, and five patients who were compound heterozygotes either for the 2183 AA-->G mutation or for the I148T mutation, in both instances with the delta F508 mutation; and (2) a patient homozygous for the early nonsense R553X mutation who showed only a moderately severe form of cystic fibrosis. Our results confirm that environmental or genetic factors unrelated to the CF disease contribute significantly to the development of the phenotype.


Assuntos
Fibrose Cística/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Genótipo , Heterozigoto , Homozigoto , Humanos , Masculino , Mutação
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