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2.
Ecotoxicol Environ Saf ; 187: 109836, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31675504

RESUMO

Toxicity of 13 ionic liquids (ILs) corresponding to different families were studied by inhibition respiration assays (15 min) using activated sludge. Toxicity increased as increasing the number of carbons in the alkyl-chain of imidazolium-based ILs, with EC50 values from 4.19 to 0.17 for 1-ethyl-3-methylimidazolium chloride ([Emim][Cl]) and 1-octyl-3-methylimidazolium chloride ([Omim][Cl]), respectively. An increase in toxicity was observed for aromatic-based ILs (pyridinium- and imidazolium-based ILs) due to the hydrophobic character of the head groups in comparison with linear structures as phosphonium and ammonium cations. Among to the anions studied fixing [Emim]+ as cation, [HSO4]- and [NTf2]- presented low EC50 values (0.34 mM and 1.69 mM, respectively) while [Cl]- and [EtSO4]- were considered harmless anions due to the hydrophilic character of chloride and the organic nature of [EtSO4]-. ILs toxicity/inhibition was determined by adding a biodegradable compound and measuring the sludge response after being in contact with the ILs for at least 15 h. The exposure of sewage sludge to ILs for more than 15 min used in short inhibition assays caused more toxic effect on microorganisms, even for [Choline][NTf2], previously defined as practically harmless (EC50 = 2.79 mM). Biodegradability assays confirmed the biodegradable nature of choline cation, related with TOC conversion of 40%, only due to cation consumption. No oxygen consumption or even lysis of microbial cells was observed for Tetrabutylammonium bis(trifluoromethylsulfonyl)imide and for 1-Ethyl-3-methylimidazolium hydrogensulphate due to the presence of anions previously defined as hazardous ([NTf2]- and [HSO4]-), maintaining their recalcitrant character to sewage systems.


Assuntos
Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Esgotos/microbiologia , Ânions , Biodegradação Ambiental , Cátions , Interações Hidrofóbicas e Hidrofílicas , Imidazóis/química , Líquidos Iônicos/química , Estrutura Molecular
3.
Clin Oncol (R Coll Radiol) ; 29(2): 99-104, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28040092

RESUMO

Over the last 60 years, the International Atomic Energy Agency (IAEA) has been working to introduce, expand and improve radiotherapy services, working with partners such as the World Health Organization (WHO) to improve cancer diagnosis, treatment, care and control through collective action in low- and middle-income countries (LMICs). The Lancet Oncology Commission on radiotherapy published a report that defined five calls for action to expand global access to radiotherapy, drawing on the previous work of the Global Taskforce on Radiotherapy for Cancer Control. The IAEA supports LMICs in the development of the required national infrastructure and regulatory authority for radiation and nuclear safety and in the training of human resources necessary for the provision of high-quality effective and safe radiation medicine services for the diagnosis, treatment and palliative care of cancer patients, helping in this way to address the different priorities outlined in the Lancet Commission report.


Assuntos
Países em Desenvolvimento , Necessidades e Demandas de Serviços de Saúde , Radioterapia , Humanos , Agências Internacionais , Neoplasias/radioterapia
4.
Chemosphere ; 91(9): 1317-23, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23562546

RESUMO

The hydrodechlorination (HDC) of diuron in aqueous phase with hydrogen using two different activated carbon-supported Pd catalysts was studied. A commercial activated carbon and one prepared by chemical activation of grape seeds with phosphoric acid (GS) were evaluated as supports, being the catalysts tested in a wide range of temperature (30-100 °C) and space-time (78-311 kgcat h mol(-1)). Diuron conversion was above 70% under all the conditions tested. The Pd catalyst supported on GS showed the highest activity in terms of diuron conversion within the temperature range studied, allowing nearly complete conversion above 50 °C. However, a gradual loss of activity with time was observed for this catalyst. A complete route of hydrogenation of diuron was elucidated. Two reaction routes one leading to fenuron and another to aniline were identified. As the temperature and space-time were increased, the formation of fenuron (via monuron) was found to be favored. The toxicity of the reaction products was evaluated, being the route to fenuron and monuron, the one giving rise to a significant decrease of ecotoxicity.


Assuntos
Carbono/química , Diurona/química , Paládio/química , Aliivibrio fischeri/efeitos dos fármacos , Catálise , Diurona/toxicidade , Extrato de Sementes de Uva/química , Hidrogenação , Ácidos Fosfóricos/química , Temperatura , Fatores de Tempo , Água/química
5.
Eur J Phys Rehabil Med ; 44(4): 437-40, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18500214

RESUMO

AIM: The aim of the study was to investigate the relationship between the clinical evidence of foot deformities in spina bifida occulta and the associated neurophysio-logical damage. METHODS: The authors studied 47 patients with foot deformities (37 flat foot, 10 pes cavus) and vertebral cleft, variably associated with enuresis, midline cutaneous lesions, and further orthopaedic deformities. An electrophysiological evaluation was performed in an attempt to investigate the peripheral nervous system in greater detail, including conventional motor and sensory nerve conduction, F-wave recording and electromyogram (EMG) testing. RESULTS: The peroneal nerve F wave latency was longer in patients with pes cavus than in those with flat foot (P<0.04). Conversely, the posterior tibial nerve F-wave latency was longer in patients with flat foot than in those with pes cavus (P<0.02). Needle EMG showed large amplitude motor unit potentials during voluntary recruitment in all patients, suggesting a neurogenic origin of these EMG changes. Neurophysiological study makes it possible to distinguish between myogenic and lower motor neuron involvement. The existence of some degree of spinal cord dysraphism may be pathophysiologically associated with foot deformities. CONCLUSION: Children with foot deformities and clinical evidence of occult spinal dysraphism should have a neuro-physiological assessment in order to obtain an early diagnosis and avoid ineffective foot surgery.


Assuntos
Enurese/etiologia , Deformidades Congênitas do Pé/etiologia , Espinha Bífida Oculta/complicações , Coluna Vertebral/patologia , Adolescente , Criança , Enurese/fisiopatologia , Feminino , Deformidades Congênitas do Pé/fisiopatologia , Humanos , Masculino , Espinha Bífida Oculta/diagnóstico , Espinha Bífida Oculta/fisiopatologia , Adulto Jovem
6.
J Bone Joint Surg Br ; 79(6): 1014-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9393923

RESUMO

We assessed peripheral nerve function during and after lower-limb lengthening by callotasis in 14 patients with short stature, using motor conduction studies. Four patients with short stature of varying aetiology showed unilateral and one showed bilateral weakness of foot dorsiflexion. Both clinical and electrophysiological abnormalities consistent with involvement of the peroneal nerve were observed early after starting tibial callotasis. There was some progressive electrophysiological improvement despite continued bone distraction, but two patients with Turner's syndrome had incomplete recovery. A greater percentage increase in tibial length did not correspond to a higher rate of peroneal nerve palsy. The function of the posterior leg muscles and the conduction velocity of the posterior tibial nerve were normal throughout the monitoring period. The F-wave response showed a longer latency at the end of the bone distraction than in basal conditions; this is probably related to the slowing of conduction throughout the entire length of the nerve.


Assuntos
Nanismo/cirurgia , Eletromiografia , Fêmur/cirurgia , Osteogênese por Distração , Nervo Fibular/fisiologia , Tíbia/cirurgia , Nervo Tibial/fisiologia , Acondroplasia/complicações , Acondroplasia/fisiopatologia , Adolescente , Adulto , Potencial Evocado Motor/fisiologia , Feminino , Doenças do Pé/etiologia , Doenças do Pé/fisiopatologia , Humanos , Perna (Membro) , Masculino , Monitorização Fisiológica , Neurônios Motores/fisiologia , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiopatologia , Condução Nervosa/fisiologia , Osteogênese por Distração/efeitos adversos , Paralisia/etiologia , Paralisia/fisiopatologia , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Tempo de Reação/fisiologia , Síndrome de Turner/complicações , Síndrome de Turner/fisiopatologia
7.
Eur Neurol ; 35(2): 93-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7796843

RESUMO

We examined the characteristics of specific components of the evoked electrospinogram (EESG) in response to tibial nerve stimulation in 28 patients with traumatic injury of the dorsal and cervical spinal cord. The data were correlated with clinical, urodynamic and additional neurophysiological findings. In the majority of patients (82%), 11 with complete and 12 with partial spinal cord lesions, the lumbar components of the EESG were normal. In 4 of these patients with complete lesion above T2 the dorsal EESG was absent. In 5 cases (18%), the lumbosacral EESG was altered in the presence of an atypical clinical syndrome characterized by persistent urinary retention associated with lower leg atrophy and reduced tendon jerks. In these cases, MRI provided evidence of an unexpected sacral lesion. Unlike the dorsal EESG reflecting the afferent dorsal column volley, the lumbar components of the EESG are usually unaffected by interruption of the cord pathways; these last events thus originate from segmental neuronal activity, the involvement of which bears witness to additional lumbosacral damage.


Assuntos
Sistema Nervoso/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/fisiopatologia , Urodinâmica , Adolescente , Adulto , Idoso , Eletrodiagnóstico/métodos , Potenciais Somatossensoriais Evocados , Feminino , Humanos , Região Lombossacral , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Medula Espinal/patologia , Traumatismos da Medula Espinal/diagnóstico
8.
Rev Esp Enferm Dig ; 82(5): 305-10, 1992 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-1485981

RESUMO

Serum gastrin levels were measured under basal conditions and after hyperproteic meal stimulation in 24 patients with non-stenotic duodenal ulcer, 78% of them were males with a mean age of 36.4 years. Results were compared with those obtained in 20 volunteers. Basal gastrin levels in patients with duodenal ulcer 46.2 +/- 17.5 pg/ml did not show any significant statistical differences when compared with those in the control group (51.01 +/- 28.1 pg/ml). After meal stimulation gastrin levels at different time intervals, were similar in patients with duodenal ulcer and in the control group. We conclude that serum gastrin does not seem to play a relevant pathogenic role in the development of duodenal ulcer; its measurement is of no value as a biological marker of duodenal ulcer disease.


Assuntos
Úlcera Duodenal/sangue , Gastrinas/sangue , Adulto , Metabolismo Basal , Proteínas Alimentares/metabolismo , Úlcera Duodenal/metabolismo , Ingestão de Alimentos , Feminino , Gastrinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade
9.
Funct Neurol ; 3(1): 47-54, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3391401

RESUMO

Autonomic function has been studied in 30 insulin-dependent diabetic children and adolescents, through five cardiovascular tests. A significant difference between the diabetic and the control subjects was found in heart rate variations after deep breathing and after standing. Fifty percent of our patients showed an altered response to one or more cardiovascular tests. Although clinical manifestations of autonomic dysfunction are not frequent in young insulin-dependent patients, early signs of functional alterations are detectable in a high percentage of them.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Diabetes Mellitus Tipo 1/fisiopatologia , Frequência Cardíaca , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Esforço Físico , Postura , Manobra de Valsalva
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