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1.
Food Microbiol ; 85: 103302, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500708

RESUMO

This study dealt with the influence of the temperature on the bacterial dynamics of two spontaneously fermented wheat sourdoughs, propagated at 21 ±â€¯1 °C (SD1) and 30 ±â€¯1 °C (SD2), during nine backslopping steps (BS1 to BS9). Proteobacteria was the only phylum found in flour. Escherichia hermannii was predominant, followed by Kosakonia cowanii, besides species belonging to the genera Pantoea and Pseudomonas. After one step of propagation, Clostridium and Bacillus cereus group became predominant. Lactobacillus curvatus was found at low relative abundance. For the second backslopping step, Clostridium was flanked by L. curvatus and Lactobacillus farciminis. From BS4 (6th day) onward, lactic acid bacteria (LAB) became predominant. L. farciminis overcame L. curvatus and remained dominant until the end of propagations for both sourdoughs. At 21 °C, Bacillus, Clostridium, Pseudomonas, and Enterobacteriaceae were gradually inhibited. At the end of propagation, SD1 harbored only LAB. Otherwise, the temperature of 30 °C favored the persistence of atypical bacteria in SD2, as Pseudomonas and Enterobacteriaceae. Therefore, the temperature of 21 °C was more suitable for sourdough propagation in Brazil. This study enhanced the knowledge of temperature's influence on microbial assembly and contributed to the elucidation of sourdough microbial communities in Brazil.


Assuntos
Pão/microbiologia , Fermentação , Metagenoma , Proteobactérias/classificação , Brasil , Contagem de Colônia Microbiana , DNA Bacteriano/genética , Farinha/microbiologia , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Microbiota , Proteobactérias/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Temperatura
2.
Environ Sci Technol ; 48(10): 5902-9, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24673199

RESUMO

Cadmium sulfide quantum dots (CdS QDs) are used in the manufacture of a number of electronics products. Their small size allows their ready entry into living cells, but as yet no attempt has been made to assess their toxicity. Our aim was to exploit two Ds transposition-induced mutant lines of Arabidopsis thaliana which tolerated exposure to CdS QDs to identify the genetic basis of their tolerance. Both a genome-wide top-down (from mutant to genes) and a bottom-up (from gene expression to phenotype) approach were applied. The differential responses of the mutants compared to the wild type showed that sensitivity to CdS QDs was unrelated to sensitivity to Cd(2+) ions. A transcriptomic analysis identified a number of genes whose transcript abundance was correlated with the tolerance. The phenotype of one of the mutants was correlated with the overexpression of ELM2, an MYB containing gene visited by a Ds transposon. Segregation analysis showed that the genetic basis of CdS QDs tolerance in both mutants was monogenic. The phenotype of the other mutant could be explained by the mutation of HCF101, a gene involved in photosynthesis.


Assuntos
Arabidopsis/genética , Arabidopsis/fisiologia , Compostos de Cádmio/toxicidade , Genoma de Planta , Pontos Quânticos/toxicidade , Sulfetos/toxicidade , Testes de Toxicidade/métodos , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Cádmio/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Genótipo , Mutação/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Sulfatos/toxicidade
3.
Cephalalgia ; 29(4): 453-64, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19170692

RESUMO

Fibromyalgia syndrome (FMS) is a chronic pain condition of unknown aetiology characterized by diffuse pain and tenderness at tender points. The aim of the study was to assess the prevalence and clinical features of FMS in the different forms of primary headaches, in a tertiary headache centre. Primary headache patients (n = 217) were selected and submitted to the Total Tenderness Score, anxiety and depression scales, Migraine Disability Assessment, allodynia questionnaire, Short Form 36 Health Survey and the Medical Outcomes Study-Sleep Scale. In patients with FMS, the Multidimensional Assessment of Fatigue, the Pain Visual Analog Scale, the Manual Tender Point Survey and the Fibromyalgia Impact Questionnaire were employed. FMS was present in 36.4% of patients and prevailed significantly in tension-type headache and in patients with higher headache frequency. Headache frequency, pericranial muscle tenderness, anxiety and sleep inadequacy were especially associated with FMS comorbidity. In the FMS patients, fatigue and pain at tender points were significantly correlated with headache frequency. FMS seems increasingly prevalent with increased headache frequency, for the facilitation of central sensitization phenomena favoured by anxiety and sleep disturbances.


Assuntos
Fibromialgia/epidemiologia , Transtornos da Cefaleia Primários/epidemiologia , Adolescente , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Comorbidade , Feminino , Fibromialgia/diagnóstico , Fibromialgia/tratamento farmacológico , Transtornos da Cefaleia Primários/diagnóstico , Transtornos da Cefaleia Primários/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Síndrome , Triptaminas/uso terapêutico , Adulto Jovem
4.
J Pharm Biomed Anal ; 17(4-5): 811-22, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9682166

RESUMO

Dissolution efficiency (D.E.), the area under a dissolution curve between defined time points, and the fit factors (f1 and f2) have been compared for the characterisation of dissolution profiles, using data from three batches of a product in nine different packs stored under two conditions. The factors f1 and f2 offer ease of calculation and a simple measure of similarity between pairs of dissolution profiles. This is well suited to the qualitative determination of 'similarity' as required by the FDA's SUPAC Guide. However, they do not provide information on individual batches, including their consistency. In contrast, D.E. does provide such information is well-suited to making quantitative comparisons amongst batches. Because D.E. has a simple physical meaning, it is easier to interpret D.E. data then corresponding f1 and f2 results. The confidence limits in D.E. values provide a useful measure of the variability in batch dissolution and allow the statistical significance of difference in D.E. between pairs of batches to be determined. Both of the above measures lead to the same conclusions regarding the similarity in protective power amongst the nine packs under test and to the value of added desiccant in maintaining the dissolution profile of the product when stored under high humidity conditions. It is concluded that D.E. offers a suitable alternative to the single point dissolution measurement for QC of immediate release products.


Assuntos
Solubilidade , Modelos Químicos
5.
CNS Neurol Disord Drug Targets ; 7(6): 524-35, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19128209

RESUMO

Central sensitisation phenomena have been well recognized in the development of migraine attacks and tension type headache. It is also known that headache frequency is related to sensitization. Though some studies have focused on the effects of symptomatic treatment on allodynia, few reports have described the action of preventive agents on the facilitating factors for central sensitisation. In this study we aim to review the factors concurrent with an increase in central sensitisation, in view of the choice of preventive agents for primary headaches. Central sensitisation phenomena are increased in pain syndromes with psycho-pathological co-morbidities. For instance, sleep disorders are a frequent symptom in headache, prevailing in chronic forms and in patients with psychiatric comorbidity. Sleep deprivation is also a factor producing hyperalgesic changes. It is known that symptoms attributable to central sensitization are diffusely pronounced in fibromyalgic (FMS) patients, and that FMS co-morbidity is frequent in primary headaches and associated with higher frequency and poorer quality of life. We report our preliminary experience in a group of 20 chronic migraine patients, treated with duloxetine 60 mg/die vs a self-management program including stretching (relaxation training) and exercise (cervical-dorsal flexion and rotation) to decrease strength and flexibility of muscles of cervical and dorsal spine headache patients. Both the treatments were effective on headache frequency and pericranial tenderness, although FMS comorbidity significantly reduced their efficacy on migraine and quality of life. The whole spectrum of action of pharmacological and non pharmacological treatments on central sensitisation mechanisms, and on their facilitating factors, should be taken into account for the best preventive therapeutic approach of primary headaches.


Assuntos
Cefaleia/prevenção & controle , Cefaleia/fisiopatologia , Manejo da Dor , Dor/fisiopatologia , Animais , Cloridrato de Duloxetina , Fibromialgia/complicações , Fibromialgia/fisiopatologia , Fibromialgia/terapia , Cefaleia/complicações , Humanos , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/fisiopatologia , Transtornos de Enxaqueca/prevenção & controle , Dor/complicações , Privação do Sono/complicações , Privação do Sono/fisiopatologia , Privação do Sono/terapia , Tiofenos/uso terapêutico
6.
Cephalalgia ; 27(8): 881-90, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17593297

RESUMO

The aim of this study was to test the function of the diffuse noxious inhibitory control system (DNIC) in chronic and episodic migraine, exploring the blink reflex (BR) modifications induced by topical application of capsaicin on the hand. We evaluated 11 migraine without aura (MA) and nine chronic migraine (CM) patients during the not symptomatic phase; they were compared with 14 non-headache subjects (N). The BR was elicited by weak electrical stimuli delivered to the right supraorbital nerve; it was obtained 10 min and 20 min after the application of 1 ml of 3% capsaicin in a cream base (Teofarma) on the skin of the dorsum of the right hand, and 60 min after capsaicin removal. The subjective pain sensation induced by capsaicin was significantly increased in CM with respect to both MA patients and normal subjects; the R2 area was increased in CM patients during capsaicin application, with respect to controls and MA patients, who did not exhibit any reflex alterations. These results may suggest a failure of DNIC and a disturbed control of the trigeminal reflex at the central level, linked with migraine frequency.


Assuntos
Piscadela/fisiologia , Capsaicina/farmacologia , Irritantes/farmacologia , Transtornos de Enxaqueca/fisiopatologia , Nociceptores/efeitos dos fármacos , Área Sob a Curva , Doença Crônica , Estimulação Elétrica , Eletrofisiologia , Mãos/inervação , Humanos , Dor/induzido quimicamente , Dor/fisiopatologia , Reflexo Anormal/fisiologia
7.
Cephalalgia ; 25(5): 359-68, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15839851

RESUMO

Previously an amplitude enhancement of laser evoked potentials (LEPs) was detected during migraine attack: we further examined pain threshold to CO2 laser stimuli and LEPs during attacks, evaluating the effect of almotriptan, lysine-acetylsalicylate and placebo treatment on cutaneous hyperalgesia to thermal stimuli delivered by CO2 laser and on LEP components. Eighteen patients suffering from migraine without aura were analysed. They were divided into three groups of six patients each, randomly assigned to lysine acetyl-salicylate, almotriptan or placebo treatments. The supraorbital zones and the dorsum of the hand were stimulated on both the symptomatic and not symptomatic side in all patients. The LEPs were recorded by 25 scalp electrodes. During attacks, the P2 wave was significantly enhanced; the amplitude of the P2 component obtained by the stimulation of the supraorbital zone during the attack on the side of the headache was significantly correlated with the intensity of pain and the frequency of headache. Both almotriptan and lysine acetyl-salicylate significantly reduced the P2 amplitude but they showed no effects on hyperalgesia to laser stimulation; headache relief following therapy was correlated with the reduction of the P2 amplitude. The cortical elaboration of laser-induced experimental pain seemed increased during migraine attack, and the severity of headache was mainly related to the increase of the later LEPs components expressing the attentive and emotive compounds of suffering. Reversion of this process appeared to be primarily responsible for the efficacy of drugs in treating migraine, though both almotriptan and lysine-acetil salicilate seemed to have no effect in reducing sensitization at second and third order nociceptive neurons.


Assuntos
Aspirina/análogos & derivados , Potenciais Evocados/fisiologia , Temperatura Alta , Hiperalgesia/tratamento farmacológico , Lasers , Lisina/análogos & derivados , Transtornos de Enxaqueca/tratamento farmacológico , Adulto , Aspirina/uso terapêutico , Potenciais Evocados/efeitos dos fármacos , Feminino , Humanos , Hiperalgesia/diagnóstico , Hiperalgesia/fisiopatologia , Indóis/uso terapêutico , Lisina/uso terapêutico , Pessoa de Meia-Idade , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/fisiopatologia , Triptaminas
8.
Proc Natl Acad Sci U S A ; 89(9): 3840-4, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1570302

RESUMO

We report a specific pattern of recognition by third-strand bases for each of the four Watson-Crick base pairs within a pyrimidine triple-helix motif as determined by PAGE: T.AT, C.GC, T.CG, and G.TA. Our recognition scheme for base triplets is in agreement with previous studies. In addition, we identified another triplet, T.CG, under physiological conditions, in which formation of triple helix was observed at equimolar ratios of the third strand and duplex target. Although different nearest-neighbor effects are expected, this finding extends the base-recognition code to all 4 base pairs in double-stranded DNA under physiological conditions. Base-composition analysis of putative triplex species provided independent evidence for the formation of triplex and confirmed the base-recognition code determined by PAGE. Moreover, the formation of triplex, as detected by gel electrophoresis, was seen to be an all-or-none phenomenon, dependent upon a single-base mismatch among 21 nucleotides. This result suggests a high specificity for the recognition of double-stranded DNA by a third strand. In addition, we report the surprising finding that triplex stability depends on the length and sequence of the target duplex DNA.


Assuntos
Oligodesoxirribonucleotídeos/química , Composição de Bases , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Ligação de Hidrogênio , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Pirimidinas/química , Coloração pela Prata , Relação Estrutura-Atividade , Temperatura
9.
Cephalalgia ; 24(8): 663-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15265055

RESUMO

The aim was to study mismatch negativity features and habituation during the interictal phase of migraine. In migraine patients, a strong negative correlation has been found between the initial amplitude of long latency auditory-evoked potentials and their amplitude increase during subsequent averaging. We studied 12 outpatients with a diagnosis of migraine without aura recorded in a headache-free interval and 10 gender- and age-matched healthy volunteers not suffering from any recurrent headache. The experiment consisted of two sequential blocks of 2000 stimulations, during which 1800 (90%) recordings for standard tones and 200 (10%) for target tones were selected for averaging. The latency of the N1 component was significantly increased in migraine patients in respect of controls in both the first and second repetitions; the MMN latency was increased in the second repetition. In the control group the MMN amplitude decreased on average by 3.2 +/- 1.4 microV in the second trial, whereas in migraine patients it showed a slight increase of 0.21 +/- 0.11 microV in the second repetition. The MMN latency relieved in the second trial was significantly correlated with the duration of illness in the migraine patients (Spearman correlation coefficient: 0.69; P < 0.05). The increases in N1 latency and MMN latency and amplitude, the latter correlated with duration of illness, seemed to be due to a reduced anticipatory effect of stimulus repetition in migraine patients. This suggests that such hypo-activity of automatic cortical processes, subtending the discrimination of acoustic stimuli, may be a basic abnormality in migraine, developing in the course of the disease.


Assuntos
Potenciais Evocados Auditivos/fisiologia , Habituação Psicofisiológica/fisiologia , Transtornos de Enxaqueca/fisiopatologia , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia
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