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1.
J Pediatr Adolesc Gynecol ; 35(4): 467-471, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34902561

RESUMO

STUDY OBJECTIVE: This study aimed to analyze factors related to adolescent mothers' satisfaction with childbirth. DESIGN: Prospective and cross-sectional study PARTICIPANTS: Fifty adolescent mothers with maternal age from 14 to 19 years and delivery of a single and live newborn at term SETTING: Low-risk maternity hospital INTERVENTION: The participants were invited to answer a questionnaire (North Bristol modified version of the Mackey Childbirth Satisfaction Rating Scale [mMCSRS]) with 18 items measuring childbirth satisfaction. Each item was to be rated on a 5-point Likert scale (very dissatisfied to very satisfied). MAIN OUTCOME MEASURE: The main outcome measure was the total score on the questionnaire. RESULTS: The median maternal age was 18 years (95% CI, 11-25), and the median maternal satisfaction score of adolescent mothers was 88 (95% CI, 83-90). There was a significant difference in the total scores on the mMCSRS regarding the following factors: "oral fluid and food intake during labor" (yes = 84.0 vs no = 78.0, P = 0.044); "professional who attended the birth" (physician = 78.0 vs midwife = 86.0, P = 0.022); "skin-to-skin contact" (yes = 83.0 vs no = 71.0, P = 0.004); and "breastfeeding at the first hour" (yes = 84.5 vs no = 75.5, P = 0.008). Multiple regression with a stepwise procedure identified the following independent factors: "gestational age" (coefficient = 2.14, P = 0.03), "oral fluid and food intake during labor" (coefficient = 5.30, P = 0.013), and "skin-to-skin contact" (coefficient = 11.2, P < 0.001). CONCLUSION: Satisfaction with childbirth in adolescent mothers is associated with measures that can be easily implemented in the health care system. They are chiefly the provision of oral fluid and food during labor and skin-to-skin contact. Specific strategies are thus needed to increase adolescents' satisfaction with childbirth.


Assuntos
Mães Adolescentes , Satisfação Pessoal , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Mães , Parto , Satisfação do Paciente , Gravidez , Estudos Prospectivos , Adulto Jovem
2.
Biochim Biophys Acta ; 1117(1): 55-9, 1992 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-1627593

RESUMO

Visual pigments are a class of receptor proteins that absorb light and trigger sensory signals. Retinal-containing proteins are used in nature as photoreceptors mainly in animals vision. Mammalian rhodopsin is the best studied example of a light sensor which couples photon absorption to a cascade of biochemical reactions amplifying the input signal. A surprising discovery was to find rhodopsin also in Archaebacteria and in unicellular eukaryotes. On the basis of absorption microspectroscopic measurements and of inhibition experiments on pigment biosynthetic pathways, we have recently suggested that a rhodopsin could be the functional receptor of the visual process in Euglena gracilis, a flagellate which can use light directly to promote photosynthetic reactions, or as an incident flux of information to adjust its swimming orientation. We here report purification and identification of all-trans-retinal by column chromatography, HPLC and GC-MS in E. gracilis; these findings indicate with absolute certainty that rhodopsin is the photoreceptor molecule of this microorganism.


Assuntos
Euglena gracilis/química , Retinaldeído/isolamento & purificação , Rodopsina/isolamento & purificação , Animais , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Retinaldeído/química , Rodopsina/química , Espectrofotometria Ultravioleta
3.
FEBS Lett ; 482(3): 247-51, 2000 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-11024469

RESUMO

We isolated the photoactive protein Erh, isolated from the photoreceptor of the unicellular photosynthetic flagellate Euglena gracilis. It is a 27 kDa protein with a photocycle resembling that of sensory rhodopsin, but with at least one stable intermediate. We recorded the absorption spectrum of the parent form of this protein both under native form and in the presence of hydroxylamine and sodium borohydride, and the fluorescence spectra of both the parent and intermediate forms. We suggest that Erh is a rhodopsin-like protein and propose a simple photocycle. This protein shows optical bistability, without thermal deactivation.


Assuntos
Euglena gracilis/química , Fotorreceptores Microbianos/isolamento & purificação , Animais , Cromatografia em Gel , Peso Molecular , Fotorreceptores Microbianos/química , Espectrometria de Fluorescência
4.
Vision Res ; 33(15): 2043-50, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8266645

RESUMO

We present experiments that test the effects of agents commonly used in visual pigment investigations, namely hydroxylamine (NH2OH), digitonin and triton X-100, on the photoreceptor and photoreception of Euglena. Hydroxylamine reacts with free and opsin-bound retinal, in aqueous solution, to form stable oximes, whereas digitonin and triton X-100 are the most common extractants of rhodopsin. Since previous data indicate that the chromophore present in Euglena photoreceptor is retinal, we investigated the influence of these chemicals on this organelle. The effects of these agents were studied by means of phase contrast, fluorescence and transmission electron microscopy and photobehaviour experiments. Hydroxylamine inhibited the formation of the Euglena photoreceptor. Photoaccumulation experiments on hydroxylamine-treated cells showed that they are unable to perceive light. Digitonin solubilized the crystalline structure of the photoreceptor, whereas the triton effect was limited to the membranous structures of the cell, leaving the photoreceptor unimpaired.


Assuntos
Digitonina/farmacologia , Euglena gracilis/fisiologia , Hidroxilaminas/farmacologia , Octoxinol/farmacologia , Células Fotorreceptoras de Invertebrados/efeitos dos fármacos , Animais , Hidroxilamina , Microscopia Eletrônica de Transmissão e Varredura , Microscopia de Contraste de Fase , Células Fotorreceptoras de Invertebrados/fisiologia , Células Fotorreceptoras de Invertebrados/ultraestrutura
5.
Micron ; 31(1): 27-34, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10568228

RESUMO

Among the terrestrial epilithic cyanobacteria isolated from Roman hypogea at extremely low light intensity, a non-heterocystous strain, belonging to the genus Leptolyngbya, showed a marked photobehavior. These red cyanobacteria possess an orange spot at the tip of the apical cell. Micro-spectrophotometric analysis of this tip showed an absorption spectrum with two bands, centered at 456 and 504 nm, respectively. Experiments on photo-orientation impairment of these cells, and micro-spectrophotometric analysis of the tip of impaired trichomes showed that a rhodopsin-like protein might be present in this structure. All these data could support the hypothesis of the presence of a complex photoreceptive system in this prokaryote.


Assuntos
Cianobactérias/fisiologia , Cianobactérias/ultraestrutura , Fotorreceptores Microbianos/química , Proteínas de Bactérias/análise , Luz , Microespectrofotometria
6.
Tissue Cell ; 32(6): 451-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11197227

RESUMO

Deep-etching technique was used to investigate the organization of the pellicle complex of Euglena gracilis. The interpretation of the images was further supported by SEM and TEM investigations. Our results mainly validate data obtained by previous freeze-fracture studies on the E and P faces of the outer cortical membrane. At the level of the ridges, the outer E fracture face is highly organized in a regular striated pattern, whereas the P inner face shows a particulate structure. However, our images reveal that this particulate organization of the P face is not limited to the ridges, but it is displayed also by the grooves. Moreover, this face shows two distinct layers, a particulate layer facing the cytoplasm and a striated layer facing the E face; these layers represent different true fracture levels of the same P face.


Assuntos
Euglena gracilis/ultraestrutura , Animais , Citoplasma/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Técnica de Congelamento e Réplica , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Microtúbulos/ultraestrutura
7.
Comput Biol Med ; 18(2): 57-63, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3128426

RESUMO

This paper presents an automatic system for the analysis of microorganism behaviour. The movements of free swimming microorganisms are videotaped by means of a television camera mounted on a microscope. The analysis is performed off-line by digitizing the video signal through the use of an image processor unit. Microorganism tracks are reconstructed spatially and chronologically by means of image processing techniques. From these tracks cell movement parameters are obtained. The results of our experiment in testing photoinduced movements follow.


Assuntos
Processamento de Imagem Assistida por Computador , Técnicas Microbiológicas , Algoritmos , Animais , Euglena gracilis/fisiologia , Técnicas Microbiológicas/instrumentação , Microscopia/métodos , Movimento , Estimulação Luminosa , Gravação de Videoteipe
9.
J. epilepsy clin. neurophysiol ; 18(2): 67-69, 2012.
Artigo em Inglês | LILACS | ID: lil-658982

RESUMO

OBJETIVO: Pacientes com esclerose mesial temporal (EMT) são clinicamente classificados como concordantes ou discordantes de acordo com a extensão da atividade epileptogênica. O objetivo desse estudo é verificar se as alterações metabólicas no hipocampo são diferentes nos dois grupos. MATERIAIS E MÉTODOS: Foram avaliados 33 pacientes diagnosticados com EMT, 23 concordantes (33±9 anos) e 10 discordantes (33±10 anos), e 28 controles (33±10 anos). Foi obtida espectroscopia por ressonância magnética de ambos os hipocampos (ipsi e contralateral) com aparelho de 3T e com a sequência PRESS de vóxel único com TE/TR=135/1500ms. Os principais metabólitos foram quantificados com o LCModel. Para a comparação entre os grupos foram realizados testes estatísticos com nível de significância de 0,05. RESULTADOS: Para todos os pacientes foi observada redução de NAAipsi e Cr ipsi quando comparado com o lado contralateral, porém esta diferença foi significativa apenas para o grupo de pacientes concordantes. Quando comparado com o grupo controles houve uma redução significativa de Cr ipsi e NAAipsi para os dois grupos e da relação NAA/Cr ipsi para o grupo de pacientes concordantes enquanto que a relação NAA/Cr contra estava diminuída apenas no grupo de pacientes discordantes. CONCLUSÃO: Nossos achados sugerem uma maior diminuição do NAA/Cr ipsi no grupo de pacientes concordantes e da relação NAA/Cr contra no grupo de pacientes discordantes apontando para um padrão diferente de alteração metabólica para os dois grupos. Porém é preciso aumentar o tamanho da amostra para confirmar estes resultados.


PURPOSE: Patients with mesial temporal sclerosis (MTS) are clinically classified as concordant or discordant according to the extent of epileptogenic activity. The aim of this study is to determine whether the metabolic changes in the hippocampus are different in the two groups. MATERIALS AND METHODS: 33 patients diagnosed with MTS, 23 concordant (33±9 years old) and 10 discordant (33±10 years old) and 28 controls (33±10 years old) were evaluated. We obtained magnetic resonance spectroscopy of both hippocampi (ipsilateral and contralateral) on a 3T scanner with single voxel PRESS sequence with TE/TR=135/1500ms. The main metabolites were quantified with LC Model. For comparison between groups statistical tests were performed with a significance level of 0.05. RESULTS: In all patients a reduction of NAAipsi and Cr ipsi was observed, when compared to the contralateral side, but this difference was only significant for the group of concordant patients. In comparison with controls a significant reduction of Cr ipsi and NAAipsi was observed for both groups and for Naa/Cr ipsi in the group of concordant patients while NAA/Cr contra was reduced only in the group of discordant patients. CONCLUSION: Our findings suggest a stronger decline of NAA/Cr ipsi in the group of concordant patients and of NAA/Cr contra in discordant patients, suggesting a slightly different metabolic pattern for both groups. However, we need to increase the sample size to confirm these findings.


Assuntos
Humanos , Espectroscopia de Ressonância Magnética
10.
Ann Inst Pasteur Microbiol ; 139(6): 717-26, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3150942

RESUMO

The practical criteria for the usefulness of an algal separation process for laboratory routine being effectiveness and time consumption, we tested the feasibility of a flocculation procedure to harvest large volumes of Euglena gracilis in culture. This procedure turned out to be a technically viable system which avoided tedious centrifugation and preserved E. gracilis flagellar apparatus integrity. E. gracilis cultures were treated with chitosan, a by-product derived from chitin from the exoskeleton of crustaceans. Since this polymer carries a positive charge, it functions as a polycationic coagulating agent by adsorbing onto particles in suspension and by bridging together into agglomerates, or flocs. A 96-98% reduction of suspended cells in cultures with 200 mg/l of chitosan, at pH 7.5, was obtained.


Assuntos
Quitina/análogos & derivados , Euglena gracilis/isolamento & purificação , Animais , Cátions , Quelantes , Quitosana , Eletroquímica , Eletroforese , Floculação , Concentração de Íons de Hidrogênio
11.
Biophys J ; 72(2 Pt 1): 545-53, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9017185

RESUMO

We present the light-induced photocycle of the paraflagellar swelling of Euglena gracilis. The kinetics of this process was reconstructed by sampling its fluorescence emission and switching the excitation light from 365 nm to 436 nm. Stable intermediates in the photocycle were manifested. The measured millisecond resolution kinetics best fits a Michaelis-Menten equation. The data provide strong evidence that the paraflagellar swelling, a three-dimensional natural crystal of a light-detecting protein, is the true Euglena photoreceptor.


Assuntos
Euglena gracilis/metabolismo , Luz , Células Fotorreceptoras de Invertebrados/metabolismo , Animais , Euglena gracilis/ultraestrutura , Flagelos/metabolismo , Flagelos/ultraestrutura , Processamento de Imagem Assistida por Computador , Cinética , Microscopia de Fluorescência , Fotobiologia , Rodopsina/metabolismo
12.
Electron Microsc Rev ; 4(2): 319-42, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1932586

RESUMO

Euglena is an organism that every student of biology has observed; its morphology has been a subject of interest since the early microscopic literature for its enigmatic role of "plant-like" or "animal-like" organism. Therefore, this review has no pretensions to absolute novelty, but, like a journey to the centre of the earth, will attempt to arouse the reader's curiosity by taking him inside the cell Euglena, through the canal opening into the reservoir chamber. In light of the most recent knowledge, though much remains to be clarified, the aim is to provide information from ultramicroscopical studies on the apical zone of Euglena and possible functional meanings of the structures present therein. The survey of these structures is carried on as a study in correlation: TEM of cells after various treatments is correlated with SEM of cells fixed by means of different techniques. Notes on locomotion and other features of cytological and biological interest are added to assist with the comprehension of this microorganism.


Assuntos
Euglena gracilis/ultraestrutura , Flagelos/ultraestrutura , Células Fotorreceptoras/ultraestrutura , Animais , Microscopia Eletrônica , Organelas/ultraestrutura
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