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1.
Chemosphere ; 228: 83-92, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31026633

RESUMO

The occurrence of classical and emerging halogenated flame retardants in bird samples collected between 2010-17 from the Castrejón reservoir (central Spain) was studied. Different wetland bird samples were analysed, including unhatched bird eggs and liver of dead nestlings. Polybrominated diphenylethers (PBDEs) were detected in all the samples at high concentration values, with levels up to 5167 ng/g lw. Dechloranes were found in 78% of analysed samples, but at lower concentration levels, between not detected (nd) and 2153 ng/g lw. The time trend evaluation over the sampling period showed an approximately 50% decline in mean concentrations of PBDEs. However, the most recent data for PBDEs (2016-17) still indicate that, in some cases, and based on reported LOECs, wetland birds were exposed to PBDE concentrations that are associated with possible ecological hazards.


Assuntos
Aves/metabolismo , Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Animais , Ovos/análise , Espanha , Áreas Alagadas
2.
Environ Res ; 172: 289-295, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30822562

RESUMO

This study evaluates for the first time organophosphorus flame retardant (OPFR) occurrence in the Alboran Sea delphinids (Spain). OPFRs were detected in all the individuals with concentration levels up to 24.7 µg/g lw. Twelve out of sixteen tested analytes were detected, being TBOEP which presented the highest detection frequency, and IDPP which presented the highest levels of concentration. OPFR distribution in different tissues (blubber, brain, kidney, muscle and liver) was evaluated. The pattern distribution showed the highest contribution for blubber (mean value of 68%) and the lowest contribution for liver (mean value of 2%). Seven OPFRs were detected in brain samples showing their capacity to surpass the blood-brain barrier and reach the brain. Moreover, high affinity for the brain tissue was observed. This is extremely important due to the neurotoxic effects of several compounds such as TCEP and TNBP. OPFR levels were compared with previously published PBDE concentrations, and no significant differences were observed. Taking into account the lower use and lower bioaccumulation and biomagnification capacities of OPFRs, this could indicate an additional OPFR source of pollution in addition to their use as FRs.


Assuntos
Golfinhos , Retardadores de Chama , Plastificantes , Animais , Retardadores de Chama/análise , Oceanos e Mares , Compostos Organofosforados/análise , Plastificantes/análise , Espanha , Distribuição Tecidual
3.
Nanoscale Res Lett ; 10(1): 407, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26474888

RESUMO

The atomic structure and chemistry of thin films of Bi(Fe,Mn)O3 (BFMO) films with a target composition of Bi2FeMnO6 on SrTiO3 are studied using scanning transmission electron microscopy imaging and electron energy loss spectroscopy. It is shown that Mn(4+)-rich antiphase boundaries are locally nucleated right at the film substrate and then form stepped structures that are approximately pyramidal in three dimensions. These have the effect of confining the material below the pyramids in a highly strained state with an out-of-plane lattice parameter close to 4.1 Å. Outside the area enclosed by the antiphase boundaries, the out-of-plane lattice parameter is much closer to bulk values for BFMO. This suggests that to improve the crystallographic perfection of the films whilst retaining the strain state through as much of the film as possible, ways need to be found to prevent nucleation of the antiphase boundaries. Since the antiphase boundaries seem to form from the interaction of Mn with the Ti in the substrate, one route to perform this would be to grow a thin buffer layer of pure BiFeO3 on the SrTiO3 substrate to minimise any Mn-Ti interactions.

4.
J Ophthalmol ; 2015: 189140, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075083

RESUMO

To portray Usher Syndrome type 2, analyzing choroidal thickness and comparing data reported in published literature on RP and healthy subjects. Methods. 20 eyes of 10 patients with clinical signs and genetic diagnosis of Usher Syndrome type 2. Each patient underwent a complete ophthalmologic examination including Best Corrected Visual Acuity (BCVA), intraocular pressure (IOP), axial length (AL), automated visual field (VF), and EDI OCT. Both retinal and choroidal measures were measured. Statistical analysis was performed to correlate choroidal thickness with age, BCVA, IOP, AL, VF, and RT. Comparison with data about healthy people and nonsyndromic RP patients was performed. Results. Mean subfoveal choroidal thickness (SFCT) was 248.21 ± 79.88 microns. SFCT was statistically significant correlated with age (correlation coefficient -0.7248179, p < 0.01). No statistically significant correlation was found between SFCT and BCVA, IOP, AL, VF, and RT. SFCT was reduced if compared to healthy subjects (p < 0.01). No difference was found when compared to choroidal thickness from nonsyndromic RP patients (p = 0.2138). Conclusions. Our study demonstrated in vivo choroidal thickness reduction in patients with Usher Syndrome type 2. These data are important for the comprehension of mechanisms of disease and for the evaluation of therapeutic approaches.

5.
J Biol Regul Homeost Agents ; 29(1): 115-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25864747

RESUMO

The proteasome inhibitor bortezomib is an antineoplastic drug mainly used for the treatment of multiple myeloma (MM). Despite its effectiveness, bortezomib clinical use is often limited by the onset of peripheral neuropathy (BiPN). To better understand the mechanisms of BiPN several rat and mice models have been proposed, but no studies in MM-bearing animals allowing to test the antitumor activity of the selected schedules and the role of MM by itself in peripheral nervous system damage have been reported to date. Here, we carried out a study using immunodeficient C.B-17/Prkdcscid (SCID) mice injected with RPMI8266 human MM cells and treated with bortezomib 1 mg/kg once a week for five weeks. Animals were assessed with neurophysiological, behavioral and pathological methods and tumor volume measurement was performed along the study. At the end of the study BiPN was evident in bortezomib-treated animals, and this neurotoxic effect was evident using a schedule able to effectively prevent tumor growth. However, neurophysiological and pathological evidence of MM induced peripheral nervous system damage was also reported. This model based on MM-bearing animals is more reliable in the reproduction of the clinical setting and it is, therefore, more suitable than the previously reported models of BiPN to study its pathogenesis. Moreover, it represents an optimal model to test the efficacy of neuroprotective agents and at the same time their non-interference with bortezomib antineoplastic activity.


Assuntos
Antineoplásicos/efeitos adversos , Ácidos Borônicos/efeitos adversos , Mieloma Múltiplo/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Pirazinas/efeitos adversos , Animais , Bortezomib , Modelos Animais de Doenças , Humanos , Camundongos SCID , Mieloma Múltiplo/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Cancer Chemother Pharmacol ; 68(4): 1001-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21327681

RESUMO

PURPOSE: Cisplatin is one of the most effective cytotoxic agents in the treatment of solid malignancies, but its use is limited by several side effects. Among them, peripheral neurotoxicity can be dose limiting. A liposomal formulation of cisplatin, Lipoplatin™, was developed to reduce the systemic toxicity of cisplatin but without preventing its efficacy. The aim of this study was to use an animal model to establish, through a multimodal approach, whether chronic treatment with two different schedules of Lipoplatin™, selected within the range of its anticancer effective dose, is less neurotoxic than cisplatin administration. METHODS: Female Wistar rats were treated intraperitoneally with cisplatin at a dose of 4 mg/kg or with Lipoplatin™ at doses delivering 12 or 24 mg/kg of cisplatin once weekly for 4 weeks. General toxicity was assessed by daily observation, body weight change, hematological and blood chemistry analysis, and histopathology of liver and kidney. The onset of peripheral neurotoxicity was assessed by measuring tail nerve conduction velocity (NCV), morphological and morphometric analysis of dorsal root ganglia (DRG), and morphological analysis of the sciatic nerve. RESULTS: Cisplatin induced a statistically significant reduction in body weight, the development of renal failure, and impairment in NCV with pathological alterations in the DRG and sciatic nerve. By contrast, Lipoplatin™ was markedly less nephrotoxic, and no significant weight gain reduction was observed in animals treated with both doses of the drug. Moreover, the lowest dose induced less severe damage to the peripheral nervous system with a moderate decrease in NCV and mild pathological alterations in DRG and the sciatic nerve. CONCLUSIONS: The results suggest that Lipoplatin™ 12 mg/kg is less neurotoxic than cisplatin 4 mg/kg, thus opening up the possibility of using this new formulation in future studies where its anticancer activity and the peripheral neurotoxicity will be assessed in parallel.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Síndromes Neurotóxicas/etiologia , Animais , Antineoplásicos/administração & dosagem , Peso Corporal/efeitos dos fármacos , Cisplatino/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Ratos , Ratos Wistar , Testes de Toxicidade
7.
Exp Neurol ; 226(2): 301-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20832406

RESUMO

Cisplatin, paclitaxel and bortezomib belong to some of the most effective families of chemotherapy drugs for solid and haematological cancers. Epothilones represent a new family of very promising antitubulin agents. The clinical use of all these drugs is limited by their severe peripheral neurotoxicity. Several in vivo rat models have reproduced the characteristics of the peripheral neurotoxicity of these drugs. However, since only a very limited number of cancer types can be studied in immunocompetent rats, these animal models do not represent an effective way to evaluate, at the same time, the antineoplastic activity and the neurotoxic effects of the anticancer compounds. In this study, we characterized the neurophysiological impairment induced by chronic chemotherapy treatment in BALB/c mice, a strain suitable for assessing the activity of anticancer treatments. At the end of a 4-week period of treatment with cisplatin, paclitaxel, epothilone-B or bortezomib, sensory and sensory/motor nerve conduction velocities (NCV) were determined in the caudal and digital nerves and dorsal root ganglia (DRG) and sciatic nerves were collected for histopathological analysis. The electrophysiological studies revealed that all the compounds caused a statistically significant reduction in the caudal NCV, while impairment of the digital NCV was less severe. This functional damage was confirmed by the histopathological observations evidencing axonal degeneration in the sciatic nerve induced by all the drugs associated with pathological changes in DRG induced only by cisplatin and bortezomib. These results confirm the possibility to use our models to combine the study of the antineoplastic activity of anticancer drugs and of their toxic effects on the peripheral nervous system in the BALB/c mouse strain.


Assuntos
Antineoplásicos/efeitos adversos , Modelos Animais de Doenças , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Ácidos Borônicos , Bortezomib , Cisplatino , Relação Dose-Resposta a Droga , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/patologia , Gânglios Espinais/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão/métodos , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/ultraestrutura , Condução Nervosa/efeitos dos fármacos , Paclitaxel , Doenças do Sistema Nervoso Periférico/mortalidade , Pirazinas , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia , Nervo Isquiático/fisiopatologia , Nervo Isquiático/ultraestrutura
9.
Int J Food Microbiol ; 117(3): 295-305, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17543406

RESUMO

Samples from the intestinal content and carcasses of mallard ducks (Anas platyrhynchos) were evaluated for enterococci with antimicrobial activity, presence of genes coding bacteriocins and their expression, and potential virulence factors. Enterococcus faecalis comprised the largest enterococcal species with antagonistic activity followed by E. faecium, E. hirae, Enterococcus spp., and the non-enterococci. Although all E. faecalis isolates manifested a potent direct antimicrobial activity, no activity was detected in supernatants of most producer cultures. However, all E. faecium isolates showed antimicrobial activity in their supernatants and encoded bacteriocins, although the occurrence in the isolates of several enterocin genes did not always correlate with a higher antagonistic activity in supernatants. The efaAfm determinant was the only virulence gene detected in E. faecium, while E. faecalis showed a larger number of virulence determinants, and E. hirae did not carry any of the virulence genes examined. The rapid identification of genes coding described bacteriocins permits recognition of isolates that are potentially producers of novel bacteriocins. Purification of the antimicrobial activity of E. hirae DCH5 and Lactococcus garvieae DCC43 revealed unique chromatographic fragments after MALDI-TOF mass spectrometry analysis, suggesting the antagonistic peptides were purified to homogeneity. Bacteriocinogenic E. faecium and E. hirae isolates may be considered hygienic for production of bacteriocins, and potentially safe due to their low incidence of potential virulence genes and susceptibility to most clinically relevant antibiotics. However, the presence among the enterococci of E. faecalis strains with a potent antagonistic activity and multiple virulence factors, raises concerns regarding their potential pathogenicity to consumers.


Assuntos
Bacteriocinas/biossíntese , Qualidade de Produtos para o Consumidor , Patos/microbiologia , Enterococcus/metabolismo , Contaminação de Alimentos/análise , Animais , Bacteriocinas/genética , Enterococcus/isolamento & purificação , Enterococcus/patogenicidade , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/metabolismo , Enterococcus faecalis/patogenicidade , Enterococcus faecium/isolamento & purificação , Enterococcus faecium/metabolismo , Enterococcus faecium/patogenicidade , Microbiologia de Alimentos , Humanos , Especificidade da Espécie , Virulência/genética
10.
Rev Neurol ; 42(4): 220-2, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-16521061

RESUMO

INTRODUCTION: Subdural haematoma associated to intracranial hypotension syndrome (IHS) is an infrequent complication. Its sudden early appearance in this female patient allowed us to diagnose and treat the syndrome at an early stage of development. CASE REPORT: We describe the case of a 29-year-old patient who had a caesarean with spinal anaesthesia and, 48 hours afterwards, presented IHS accompanied by focal neurological symptoms as a consequence of a subdural haematoma. Performing an emergency computerised tomography scan and magnetic resonance imaging (MRI) at 14 hours allowed early diagnosis and treatment to be established. CONCLUSIONS: MRI is essential to confirm the clinical suspicion of IHS and thus avoid the need to submit the patient to invasive tests. In this way, treatment for the IHS can be initiated at an early stage and the subdural haematoma can be resolved without the need for surgical drainage.


Assuntos
Hematoma Subdural/complicações , Hipotensão Intracraniana/etiologia , Adulto , Placa de Sangue Epidural , Feminino , Hematoma Subdural/patologia , Hematoma Subdural/terapia , Humanos , Hipotensão Intracraniana/diagnóstico , Hipotensão Intracraniana/patologia , Hipotensão Intracraniana/terapia , Imageamento por Ressonância Magnética , Síndrome
11.
Rev. neurol. (Ed. impr.) ; 42(4): 220-222, 16 feb., 2006. ilus
Artigo em Es | IBECS | ID: ibc-045691

RESUMO

Introducción. El hematoma subdural asociado al síndrome de hipotensión intracraneal (SIH) es una complicación infrecuente. Su aparición brusca y temprana en esta paciente permitió diagnosticar y tratar precozmente el síndrome. Caso clínico. Mujer de 29 años sometida a una cesárea con raquianestesia, que presentó a las 48 horas un SIH, acompañado de síntomas neurológicos focales, como consecuencia de un hematoma subdural. La realización de una tomografía computarizada en condiciones de urgencia y de una resonancia magnética a las 14 horas permitió acometer un diagnóstico y un tratamiento tempranos. Conclusiones. La resonancia magnética es fundamental para confirmar la sospecha clínica del SIH y evitar el empleo de pruebas invasivas para el paciente. De este modo, se puede instaurar de forma precoz el tratamiento del SIH y tener la posibilidad de conseguir la resolución del hematoma subdural sin necesidad de un drenaje quirúrgico (AU)


Introduction. Subdural haematoma associated to intracranial hypotension syndrome (IHS) is an infrequent complication. Its sudden early appearance in this female patient allowed us to diagnose and treat the syndrome at an early stage of development. Case report. We describe the case of a 29-year-old patient who had a caesarean with spinal anaesthesia and, 48 hours afterwards, presented IHS accompanied by focal neurological symptoms as a consequence of a subdural haematoma. Performing an emergency computerised tomography scan and magnetic resonance imaging (MRI) at 14 hours allowed early diagnosis and treatment to be established. Conclusions. MRI is essential to confirm the clinical suspicion of IHS and thus avoid the need to submit the patient to invasive tests. In this way, treatment for the IHS can be initiated at an early stage and the subdural haematoma can be resolved without the need for surgical drainage (AU)


Assuntos
Feminino , Gravidez , Adulto , Humanos , Hematoma Subdural/complicações , Hipotensão Intracraniana/complicações , Espectroscopia de Ressonância Magnética/uso terapêutico , Cesárea , Raquianestesia/efeitos adversos , Hipotensão Intracraniana/diagnóstico , Hipotensão Intracraniana/fisiopatologia , Placa de Sangue Epidural
12.
Rev Neurol ; 37(7): 641-3, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-14582021

RESUMO

INTRODUCTION: Ventriculus terminalis is the name given to a congenital disorder that consists in the appearance of a small oval ependymal cystic cavity in the conus medullaris. It is formed during embryogenesis as a result of the differentiation between the canalisation and regression of the spinal cord. The aim of this study is to describe the findings obtained by magnetic resonance (MR) imaging concerning the dilation of the ventriculus terminalis in a symptomatic patient. CASE REPORT: A 41-year-old female with a three-year history of lower back pain and irradiated pain in the left leg, together with paresthesias. The physical exploration revealed hypoesthesia with a low level of sensitivity in D12, L1 and L2. MR images revealed the presence of a cystic lesion located in the conus medullaris, with a well defined outline, and which was not enhanced following contrast IV. CONCLUSION: The ventriculus terminalis is the ependymal cavity that lies in the conus medullaris. It may present an abnormal dilation and we need to know of its existence, where it is typically located and its signal characteristics in MR in order to be able to diagnose and differentiate it from cystic tumours situated in the same place, which can display a similar appearance in MR images. The therapeutic management of these patients will depend on their clinical progress. MR scanning is fundamental for diagnosing and monitoring symptomatic patients.


Assuntos
Dilatação Patológica/complicações , Dor Lombar/etiologia , Doenças da Medula Espinal/patologia , Adulto , Cistos/complicações , Cistos/patologia , Diagnóstico Diferencial , Dilatação Patológica/patologia , Feminino , Humanos , Dor Lombar/patologia , Região Lombossacral , Imageamento por Ressonância Magnética
13.
Tumori ; 82(5): 459-62, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9063524

RESUMO

Between May 1990 and December 1995, 16 patients with primary or recurrent unresectable rectal cancer were treated by isolated pelvic perfusion. All patients had been previously treated and were considered unsuitable for surgery or further systemic chemotherapy or radiotherapy. The treatment was based on a perfusion lasting 90 min at 40.5 C degrees with 5-fluorouracil, mitomycin-C and mitoxantrone. Whenever technically feasible (10 cases), continuous intraarterial chemotherapy (through a Medtronic device with a catheter in the inferior mesenteric artery) was administered postoperatively. Two complete responses and 2 partial responses were observed; 8 other patients showed stable disease. One patient did not show any response. Finally, 3 patients for various reasons were not assessable. All patients experienced immediate relief of pain. No major side effects directly related to isolated pelvic perfusion were recorded; a transitory bone marrow depletion was observed in all cases. In conclusion, isolated pelvic perfusion is useful in inoperable disease of the pelvis by reliably relieving pain and thereby improving the patients quality of life.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Retais/tratamento farmacológico , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Hipertermia Induzida , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitoxantrona/administração & dosagem , Pelve , Perfusão/efeitos adversos , Perfusão/métodos , Resultado do Tratamento
14.
Minerva Anestesiol ; 58(4): 191-4, 1992 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-1620414

RESUMO

This double-blind study was carried out at random on 2 groups of 10 women, comparable by age and weight, all having to undergo a cholecystectomy as a result of gall-bladder stones. Group A received 10 mg os of oxycodone, while group B received 1000 mg os of paracetamol. The level of sedation before the operation, post-operative pain, canalization and the side effect were recorded. The results showed that the group treated with oxycodone presented a greater degree of pre-operative sedation. As far as the post-operative pain is concerned, no significant differences were seen between the two groups based on both what was expressed by the patients and what was reported by a visual analog. Furthermore, no significant differences were noted as far as the side effects and canalization are concerned.


Assuntos
Acetaminofen/administração & dosagem , Colecistectomia , Oxicodona/administração & dosagem , Medicação Pré-Anestésica , Acetaminofen/efeitos adversos , Administração Oral , Adulto , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Oxicodona/efeitos adversos
15.
Acta Eur Fertil ; 18(6): 397-401, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3454505

RESUMO

Plasmatic Human Chorionic Gonadotropin (hCG) was studied in 41 patients undergoing salpingectomy for tubal pregnancy. On the temporal scale of our research, a biexponential model proved to be adequate to describe hCG clearance; the combined reading of the results of this research and those of other Authors have led us to maintain that hCG clearance is characterised by at least three components. HCG clearance was faster in patients with a higher initial hCG. Nevertheless the problem of hCG clearance depending on its initial value remains unsolved and requires further investigation. The regression curve and relative hCG values obtained in this study can be used as reliable models of comparison in the monitoring of patients undergoing conservative surgical treatment of tubal pregnancy.


Assuntos
Gonadotropina Coriônica/sangue , Tubas Uterinas/cirurgia , Gravidez Tubária/cirurgia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Gravidez Tubária/sangue
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