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1.
J Stomatol Oral Maxillofac Surg ; 123(1): 81-84, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33429064

RESUMO

Management of soft tissue avulsion after facial bites could be challenging in some situation. We presented the case of a 32 years old men suffering from a full thickness avulsion of the left lower lip and cheek after a dog bite. Even if the lip fragment was initially put on the bin, a microvascular replantation was performed. The vascularization was based on the left inferior labial artery. No veins were found. We used post-operative leech therapy to avoid venous congestion during 10 days. A large antibiotherapy was conducted. Adaptation of antibiotics blood concentration was also necessary due to the permanent bleeding caused by leech therapy. At the 6 month consultation, the patient recovered an impressive labial function and sensibility. Replantation gives the best functional and esthetical outcomes in these rare and complex cases. Artificial blood drainage, large antibiotic therapy and close post-operative follow-up are significant parts of the replantation success.


Assuntos
Mordeduras e Picadas , Procedimentos de Cirurgia Plástica , Animais , Mordeduras e Picadas/complicações , Mordeduras e Picadas/cirurgia , Cães , Face , Humanos , Lábio/cirurgia , Microcirurgia
2.
Complement Ther Med ; 55: 102539, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33234406

RESUMO

OBJECTIVE: Whole-Body Cryotherapy (WBC) has seen a recent surge in popularity with patients with inflammatory conditions, athletes, and even people seeking to improve general health and quality of life. WBC treatment usually requires participation in a dozen of 3-min long sessions. But compliance is considered difficult due to possible cold-induced unpleasant sensations. Based on hedonic psychology assumptions, ratings of pleasure-displeasure experienced during a taks or activity may be important to understand individual differences in attendance. METHODS: Two hundred fifty nine customers from two French cryocenters took the Feeling Scale immediately after their first WBC session. RESULTS: End affect appeared to be negatively valenced (M = -1.85, SD = 1.38, 95 % confidence interval: -2.02 to -1.68). Additional statistical analyses revealed a moderating influence of past experience, in women only. Similarly, BMI was found to be negatively associated with displeasure in women, but not in men. CONCLUSION: These findings are discussed and further research directions are suggested.


Assuntos
Crioterapia/psicologia , Prazer , Adulto , Fatores Etários , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores Sexuais , Inquéritos e Questionários , Fatores de Tempo
3.
Cryobiology ; 97: 12-19, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33130106

RESUMO

In order to determine the required duration of whole-body exposure to extreme cold (-110 °C) in males and females for achieving the same cold-induced response, a mathematical model of skin cooling kinetics was developed. This modeling is derived from the implementation of a new experimental cryotherapy protocol to obtain continuous skin temperature maps over time. Each 3-min whole-body cryostimulation session was divided into six incremental sessions of 30 s carried out over six consecutive days. Seventeen young, healthy subjects (8 males aged 22.6 ±3.0 years and 9 females aged 23.7 ±4.7 years) agreed to participate in this study. The smallest sex-related difference in temperature was found in the trunk area (2.93 °C after 3 min) while the greatest temperature drop was found in the lower limbs (5.92 °C after 3 min). The largest temperature variation was observed between the trunk and the lower limbs, and peaked at 2.67 °C in males and 6.99 °C in females. For both sexes, skin cooling kinetics showed a strong transient exponential type decrease followed by linear regression behavior. It appeared that for achieving the same cold-induced response, the required duration of cryostimulation is longer for males. For example, a trunk skin cooling of -12 °C could be achieved in 125s for females vs 170s for males (+36% longer); for the lower limbs, the same skin cooling magnitude could be reached after 87s for females vs 140s for males (+62% longer).


Assuntos
Temperatura Baixa , Criopreservação , Adulto , Criopreservação/métodos , Crioterapia , Feminino , Humanos , Masculino , Caracteres Sexuais , Temperatura Cutânea , Adulto Jovem
4.
Appl Psychol Health Well Being ; 12(2): 259-267, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31515948

RESUMO

BACKGROUND: We aimed at evaluating the feasibility and effects of intense (i.e. -90°C) whole-body cryostimulation (WBC) on somnolence and psychological well-being in an older-adult patient diagnosed with restless legs syndrome (RLS). METHODS: An interrupted time series approach was used in which the efficacy of cryostimulation was evaluated by measuring self-reported fatigue, wake time sleepiness, and well-being several times prior to, during, and after exposure to treatment (i.e. daily 3-min sessions of intense WBC). RESULTS: No adverse event occurred. Reported levels of sleepiness decreased immediately following the beginning of the treatment phase. In the same time, self-reported well-being significantly increased. Effects sizes were of large magnitude. CONCLUSION: In summary, the present study demonstrated that daily exposure to extremely cold air in an enclosed space for 2 weeks was feasible and effective in promoting physical and psychological states in an older patient with sleep disturbances.


Assuntos
Crioterapia , Distúrbios do Sono por Sonolência Excessiva/terapia , Fadiga/terapia , Síndrome das Pernas Inquietas/complicações , Idoso , Crioterapia/efeitos adversos , Crioterapia/métodos , Distúrbios do Sono por Sonolência Excessiva/etiologia , Fadiga/etiologia , Estudos de Viabilidade , Humanos , Masculino , Satisfação Pessoal , Resultado do Tratamento
5.
J Stomatol Oral Maxillofac Surg ; 119(6): 455-460, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30098447

RESUMO

INTRODUCTION: Mandibular reconstruction using fibula free flap has been improved in the last decade with computer-aided design and computer-aided manufacturing (CAD/CAM) but any functional and aesthetic evaluation of their reattempts has been realized. Aim of this retrospective study is to compare functional and morphologic outcomes after mandibular reconstruction with fibula free flap using CAD/CAM or conventional peroperative shaping for mandible reconstruction. Moreover, we compared quality of life, patient and surgery characteristics in the two groups. PATIENTS AND METHODS: We realized a monocentric retrospective analyzed of 25 cases of unilateral mandibular reconstruction divided in two groups, using CAD/CAM (12 patient) or conventional approach (13 patients) between April 2012 and March. Functional and aesthetic measurements were performed postoperatively. RESULTS: Mouth opening, laterotrusion and protrusion of the mandible seemed to be improved in CAD/CAM group compared with conventional group but did not differ significantly. Quality of life, bite force, masticatory ability, eating and chewing satisfaction, appearance and social activity satisfaction did not differ significantly in the two groups. CONCLUSION: Even if no superiority has been established for CAD/CAM group regarding functional and aesthetic outcomes, a prospective design of future studies and transdisciplinary approach should improve our data and their interpretations. Thus, the integration of virtual planning and guided surgery is definitely of significant value and must be considered in complex maxillofacial reconstructions.


Assuntos
Retalhos de Tecido Biológico , Desenho Assistido por Computador , Estética Dentária , Humanos , Mandíbula , Estudos Prospectivos , Qualidade de Vida , Estudos Retrospectivos
7.
J Proteomics ; 78: 508-21, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23128297

RESUMO

Plant cell walls are complex structures critical for plant fitness and valuable for human nutrition as dietary fiber and for industrial uses such as biofuel production. The cell wall polysaccharides in wheat endosperm consist of two major polymers, arabinoxylans and beta-glucans, as well as other minor components. Most of these polysaccharides are synthesized in the Golgi apparatus but the mechanisms underlying their synthesis have yet to be fully elucidated and only a few of the enzymes involved have been characterized. To identify actors involved in the wheat endosperm cell wall formation, we used a subcellular fractionation strategy to isolate Golgi-enriched fractions from endosperm harvested during active cell wall deposition. The proteins extracted from these Golgi-enriched fractions were analyzed by LC-MS/MS. We report the identification of 1135 proteins among which 64 glycosyltransferases distributed in 17 families. Their potential function in cell wall synthesis is discussed. In addition, we identified 63 glycosylhydrolases, some of which may be involved in cell wall remodeling. Several glycosyltransferases were validated by showing that when expressed as fusion proteins with a fluorescent reporter, they indeed accumulate in the Golgi apparatus. Our results provide new candidates potentially involved in cell wall biogenesis in wheat endosperm.


Assuntos
Parede Celular/enzimologia , Endosperma/enzimologia , Glicosiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Triticum/enzimologia , Fibras na Dieta/metabolismo , Complexo de Golgi/enzimologia , Humanos , Espectrometria de Massas , Polissacarídeos/biossíntese
8.
J Microsc ; 247(1): 78-93, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22612643

RESUMO

In fleshy fruits, the variability of cell morphology at the fruit scale is largely unknown. It presents both a huge variability and a high level of organization. Better knowledge of cell morphology heterogeneity within the fruit is necessary to understand fruit development, to model fruit mechanical behaviour, or to investigate variations of physico-chemical measurements. A generic approach is proposed to build cartographies of cell morphology at the fruit scale, which depict regions corresponding to different cell morphologies. The approach is based on: (1) sampling the whole fruit at known positions; (2) imaging and quantifying local cell morphology; (3) pooling measurements to take biological variability into account and (4) projecting results in a morphology model of the whole fruit. The result is a synthetic representation of cell morphology variations within the whole fruit. The method was applied to the characterization of cell morphology in tomato pericarp. Two different imaging scales that provided complementary descriptions were used: 3D confocal microscopy and macroscopy. The approach is generic and can be adapted to other fruits or other products.


Assuntos
Frutas/citologia , Solanum lycopersicum/citologia , Forma Celular , Microscopia/métodos
10.
Bull Soc Pathol Exot ; 104(2): 97-104, 2011 May.
Artigo em Francês | MEDLINE | ID: mdl-21509522

RESUMO

In the Southern hemisphere, Réunion Island acts as a sentinel for infections preferentially occurring during the austral winter that are likely to reach the Northern hemisphere a few months later. We relate the main features concerning patients that were admitted during years 2009 and 2010 in our intensive care unit with an A(H1N1)v2009 infection, mainly for acute respiratory distress. Demographic, clinical, and biological data as well as given medications and outcome were prospectively collected among all PCR-confirmed influenza-infected patients. In 2009 and 2010, 25 patients met the criteria. Patients' median age was 40.4 (±17.4) years. Most of them (22/25) had comorbidities such as: chronic diseases, overweight, obesity, pregnancy, and Down syndrome. Maximum bed-occupation rate was 10 days per million inhabitants. Main diagnosis for ICU admission was virus-related pneumonia. Twenty-two out of 25 patients needed mechanical ventilation, some required rescue therapies such as extracorporeal membranous oxygenation (ECMO) or hi-frequency oscillation ventilation (HFOV), both only available in few French hospitals. Within the study period, 12 patients died (48%) mainly of multi-organ failure. Through 2009 and 2010 autumn and winter periods, for several weeks, the A(H1N1)v2009 virus infection resulted in a significant increase of workload in Réunion Island ICUs. In 2010, the failure of the mass immunization campaign, particularly among the at-risk groups, led to severe cases of A(H1N1)v2009 infections, particularly among patients with comorbidities. Our data may contribute toward better management of influenza virus pandemics in the future.


Assuntos
Epidemias , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Adolescente , Adulto , Idoso , Antivirais/uso terapêutico , Terapia Combinada , Comorbidade , Suscetibilidade a Doenças , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/complicações , Influenza Humana/terapia , Influenza Humana/virologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Admissão do Paciente/estatística & dados numéricos , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , Estudos Prospectivos , Respiração Artificial , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/etiologia , Reunião/epidemiologia , Adulto Jovem
11.
Planta ; 233(2): 393-406, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21061017

RESUMO

In addition to the starchy endosperm, a specialized tissue accumulating storage material, the endosperm of wheat grain, comprises the aleurone layer and the transfer cells next to the crease. The transfer cells, located at the ventral region of the grain, are involved in nutrient transfer from the maternal tissues to the developing endosperm. Immunolabeling techniques, Raman spectroscopy, and synchrotron infrared micro-spectroscopy were used to study the chemistry of the transfer cell walls during wheat grain development. The kinetic depositions of the main cell wall polysaccharides of wheat grain endosperm, arabinoxylan, and (1-3)(1-4)-ß-glucan in transfer cell walls were different from kinetics previously observed in the aleurone cell walls. While (1-3)(1-4)-ß-glucan appeared first in the aleurone cell walls at 90°D, arabinoxylan predominated in the transfer cell walls from 90 to 445°D. Both aleurone and transfer cell walls were enriched in (1-3)(1-4)-ß-glucan at the mature stage of wheat grain development. Arabinoxylan was more substituted in the transfer cell walls than in the aleurone walls. However, arabinoxylan was more feruloylated in the aleurone than in the transfer cell walls, whatever the stage of grain development. In the transfer cells, the ferulic acid was less abundant in the outer periclinal walls while para-coumarate was absent. Possible implications of such differences are discussed.


Assuntos
Parede Celular/metabolismo , Grão Comestível/metabolismo , Endosperma/metabolismo , Polissacarídeos/metabolismo , Triticum/metabolismo , Diferenciação Celular , Grão Comestível/crescimento & desenvolvimento , Endosperma/citologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Xilanos/análise
12.
Drugs Today (Barc) ; 46(10): 735-42, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21076710

RESUMO

Cabazitaxel is a new taxane characterized by convenient administration, a favorable pharmacokinetic and safety profile and a decreased propensity for P-glycoprotein (Pgp)-mediated drug resistance. In preclinical studies cabazitaxel inhibited cell growth in a wide range of human cancer cell lines, including tumor models expressing Pgp. Phase I clinical trials established that the cabazitaxel side effect profile is similar to that reported for taxanes, with neutropenia and neuropathy being the most commonly reported toxicities. Further clinical studies have revealed that cabazitaxel is clinically active in women with taxaneresistant metastatic breast cancer and in men with metastatic castration-resistant prostate cancer previously treated with docetaxel. The TROPIC phase III trial concluded that, compared to mitoxantrone/prednisone, the combination cabazitaxel/prednisone conferred a statistically significantly longer overall survival in patients after treatment with a docetaxel-containing regimen, providing the basis for its FDA approval in 2010.


Assuntos
Antineoplásicos/uso terapêutico , Taxoides/uso terapêutico , Animais , Feminino , Humanos , Masculino , Neoplasias/tratamento farmacológico , Taxoides/efeitos adversos , Taxoides/metabolismo , Taxoides/farmacologia
13.
J Exp Bot ; 61(6): 1771-83, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20385545

RESUMO

Seed storage proteins are of great importance in nutrition and in industrial transformation because of their functional properties. Brachypodium distachyon has been proposed as a new model plant to study temperate cereals. The protein composition of Brachypodium grain was investigated by separating the proteins on the basis of their solubility combined with a proteomic approach. Salt-soluble proteins as well as salt-insoluble proteins separated by two-dimensional gel electrophoresis revealed 284 and 120 spots, respectively. Proteins from the major spots were sequenced by mass spectrometry and identified by searching against a Brachypodium putative protein database. Our analysis detected globulins and prolamins but no albumins. Globulins were represented mainly by the 11S type and their solubility properties corresponded to the glutelin found in rice. An in silico search for storage proteins returned more translated genes than expressed products identified by mass spectrometry, particularly in the case of prolamin type proteins, reflecting a strong expression of globulins at the expense of prolamins. Microscopic examination of endosperm cells revealed scarce small-size starch granules surrounded by protein bodies containing 11S globulins. The presence of protein bodies containing glutelins makes B. distachyon closer to rice or oat than to wheat endosperm.


Assuntos
Proteínas de Plantas/metabolismo , Poaceae/metabolismo , Sementes/metabolismo , Eletroforese em Gel Bidimensional , Globulinas/metabolismo , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Poaceae/genética , Poaceae/ultraestrutura , Prolaminas/metabolismo , Sementes/genética , Sementes/ultraestrutura
14.
J Microsc ; 232(1): 44-55, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19017200

RESUMO

This paper deals with the characterization of layered structures sampled with respect to a reference surface. A scheme where thick slabs are sampled perpendicular to a curved surface is considered, resulting in a non-uniform sampling of the structure. We present an estimation procedure based on the Horvitz-Thompson principle. An approximation of the sampling probability is proposed, which depends on the local surface curvatures, on the slab dimensions and on the intensity function of slab anchors. The practical determination of local parameters is detailed for the case of a revolution surface. The procedure is applied to the estimation of surface area density of cell walls in tomato pericarp.


Assuntos
Parede Celular/ultraestrutura , Microscopia Confocal/métodos , Solanum lycopersicum/ultraestrutura , Processamento de Imagem Assistida por Computador
15.
Appl Spectrosc ; 62(8): 895-900, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18702863

RESUMO

Infrared microspectroscopy and immunolabeling techniques were employed in order to obtain deeper insight into the biochemical nature of aleurone cell walls of wheat grain. The use of a synchrotron source, thanks to its intrinsic brightness, has provided unprecedented information at the level of a few micrometers and has allowed the discrimination of various polysaccharides in cell walls. The high spectral quality obtained in the small analyzed domain has been beneficial in estimating the relative proportions of beta-glucan and arabinoxylan, through the use of principal component analysis (PCA). The highest amount of beta-glucan is found in periclinal cell walls close to the starchy endosperm. The junction regions between aleurone cells are enriched in arabinoxylan. At the early stage of wheat grain development (271 degrees D), the chemical composition along the cell walls is more heterogeneous than at the mature stage. Both synchrotron infrared microspectroscopy and immunolabeling experiments made it possible to reveal the spatial heterogeneity of the various chemical compositions of aleurone cell walls.


Assuntos
Parede Celular/química , Proteínas de Plantas/química , Triticum , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Síncrotrons , Triticum/química , Triticum/citologia , Xilanos/química , beta-Glucanas/química
16.
Br J Cancer ; 97(9): 1218-24, 2007 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-17968427

RESUMO

Despite its increasing clinical use, almost no data are currently available about paclitaxel effects on non-cancerous mammary epithelial cells. We have previously established paclitaxel-resistant sub-cell lines (paclitaxel-surviving populations, PSPs; n=20), and sensitive controls (control clones, CCs; n=10), from the untransformed human mammary epithelial cell line HME1. In this study, we aimed to establish whether paclitaxel resistance was associated with a modified sensitivity to paclitaxel-induced aneuploidy. For this purpose, we analysed basal and paclitaxel-induced chromosome missegregation, apoptosis and aberrant spindle multipolarisation as well as microtubular network composition for each subline. PSP sublines showed higher basal and paclitaxel-induced chromosome missegregation than the CC sublines. This phenomenon was associated with resistance to paclitaxel-induced apoptosis. No significant difference in paclitaxel-induced spindle pole abnormalities between CC and PSP sublines was found. Besides, we showed that a majority of PSPs display a constitutively disrupted microtubular network composition due to aberrant tubulin expression and post-translational modifications. These results clearly indicate that paclitaxel resistance in untransformed human mammary epithelial cells is related to an increased susceptibility to acquire aneuploidy in response to this agent. The consequences of these paclitaxel-associated alterations could be deleterious as they can potentially trigger tumorigenesis.


Assuntos
Aneuploidia , Antineoplásicos Fitogênicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Glândulas Mamárias Humanas/efeitos dos fármacos , Paclitaxel/farmacologia , Apoptose , Western Blotting , Segregação de Cromossomos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Humanos , Glândulas Mamárias Humanas/patologia , Fenótipo
17.
Br Poult Sci ; 48(3): 370-80, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17578701

RESUMO

1. The current experiment is the second part of a study about the effects of wheat quality on digestibility of pelleted diets for broiler chickens. In the first part, it was shown that a hard cultivar resulted in a negative effect on starch digestibility in two divergent lines of chickens (D+ and D-) selected for digestion capacity. The aim of this second part was to investigate the reasons for this negative effect of a hard cultivar (Baltimor) compared to a soft one (Scipion) in D+ and D- lines. 2. Proventriculus pepsin activity and pancreas proteolytic and amylolytic activities were estimated in 4 pools of birds: 'D+ line (Baltimor fed)', 'D+ line (Scipion fed)', 'D- line (Baltimor fed)' and 'D- line (Scipion fed)'. Results suggested the greatest amount of pepsin units per g BW for D+ birds and the lowest amount of pancreas proteolytic units per g BW for D+ birds fed Scipion wheat. Pancreas showed very similar alpha-amylase activities among treatments. 3. In vitro hydrolyses of wheat gluten proteins with proventriculus extracts from pools of D+ and D- birds did not show any differences between hard and soft cultivars, whatever the origin of pools. 4. Pepsin hydrolysis of fine (300 to 425 microm) and coarse (1180 to 1600 microm) fractions from wheat flours (Baltimor or Scipion) showed that the 30 min proteolysis rate was highest for the fine fraction in both cultivars. No difference was observed with extended hydrolysis time. 5. In vitro digestion simulation of whole wheat flours confirmed the results previously obtained in vivo, with a negative effect of hard cultivar on starch digestion rate and no effect on protein digestion. 6. Laser particle size analyses showed that ileum digesta from birds fed with hard wheat cultivar showed the highest proportion of coarse particles. 7. Microscopic analyses of D+ ileum digesta revealed that the concentration of undigested starch granules in the subaleurone area of wheat bran particles was the highest with hard cultivar. 8. The results suggested that physical entrapment of starch granules in coarse particles was a major explanation for decreased starch digestibility values in chickens fed hard wheat diets.


Assuntos
Ração Animal , Galinhas/fisiologia , Digestão/fisiologia , Triticum/classificação , Triticum/metabolismo , Ração Animal/normas , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Sistema Digestório/anatomia & histologia , Genótipo , Masculino , Tamanho do Órgão , Triticum/química
18.
Biochim Biophys Acta ; 1725(1): 10-8, 2005 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-16023787

RESUMO

The adsorption of condensed tannins (procyanidins) of varying degrees of polymerisation and percentage of galloylation on solid polysaccharides substrates was quantified using the Langmuir isotherms formulation. Pectins and xyloglucans, which are soluble polysaccharides, were first cross-linked by, respectively, dibromopropane and epichlorohydrin to obtain insoluble covalent gels. Cellulose and starch, being insoluble in the buffer solution at room temperature, were used as bought. Apparent affinity constants obtained for the pure polysaccharides were as follows: pectin>>xyloglucan>starch>cellulose. The apparent affinity constants increased with the molecular weight of the procyanidins, except with cellulose. Higher affinities were obtained with pectin, a polysaccharide having the ability to develop a gel-like network, forming hydrophobic pockets able to encapsulate procyanidins. Filamentous and globular polysaccharides, like cellulose and xyloglucan, bound procyanidins weakly. Higher apparent saturation levels were obtained for cellulose and xyloglucans, the arrangement of which would favour cooperativity and stacking. Pectin had lower saturation levels probably due to a steric hindrance effect.


Assuntos
Parede Celular/química , Malus/química , Polissacarídeos/química , Proantocianidinas/química , Absorção , Celulose/química , Reagentes de Ligações Cruzadas , Glucanos/química , Ligação de Hidrogênio , Modelos Químicos , Pectinas/química , Extratos Vegetais , Amido/química , Xilanos/química
19.
Plant Physiol ; 125(4): 1710-22, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11299352

RESUMO

The STA8 locus of Chlamydomonas reinhardtii was identified in a genetic screen as a factor that controls starch biosynthesis. Mutations of STA8 cause a significant reduction in the amount of granular starch produced during nutrient limitation and accumulate phytoglycogen. The granules remaining in sta8 mutants are misshapen, and the abundance of amylose and long chains in amylopectin is altered. Mutations of the STA7 locus, which completely lack isoamylase activity, also cause accumulation of phytoglycogen, although sta8 and sta7 mutants differ in that there is a complete loss of granular starch in the latter. This is the first instance in which mutations of two different genetic elements in one plant species have been shown to cause phytoglycogen accumulation. An analytical procedure that allows assay of isoamylase in total extracts was developed and used to show that sta8 mutations cause a 65% reduction in the level of this activity. All other enzymes known to be involved in starch biosynthesis were shown to be unaffected in sta8 mutants. The same amount of total isoamylase activity (approximately) as that present in sta8 mutants was observed in heterozygous triploids containing two sta7 mutant alleles and one wild-type allele. This strain, however, accumulates normal levels of starch granules and lacks phytoglycogen. The total level of isoamylase activity, therefore, is not the major determinant of whether granule production is reduced and phytoglycogen accumulates. Instead, a qualitative property of the isoamylase that is affected by the sta8 mutation is likely to be the critical factor in phytoglycogen production.


Assuntos
Amilopectina/genética , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Amido/genética , Amilopectina/ultraestrutura , Animais , Argininossuccinato Liase/genética , Argininossuccinato Liase/metabolismo , Chlamydomonas reinhardtii/ultraestrutura , Cruzamentos Genéticos , Dosagem de Genes , Teste de Complementação Genética , Genótipo , Mutagênese Insercional , Plantas Geneticamente Modificadas , Proteínas Recombinantes/metabolismo
20.
J Biomed Mater Res ; 52(4): 716-24, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11033555

RESUMO

Beta-1 integrin plays a major role in cell attachment and is believed to be involved in mediating the interactions of chondrocytes with their environment. We previously reported that articular chondrocytes propagated in microcarrier spinner culture proliferated and reexpressed their chondrocytic protein. The goal of the present study was to investigate the expression of beta-1 integrin by chondrocytes growing on the surface of microcarriers. Nasal chondrocytes (4 x 10(3)/cm(2)) were seeded on microcarriers and incubated at 37 degrees C, 5% CO(2), 60 rpm. Expression of chondrocyte markers and beta-1 integrin was determined using reverse transcriptase-polymerase chain reaction and immunocytochemical analyses. De novo synthesis of sulfate-containing proteoglycans was studied using 35SO(4) incorporation techniques. Like articular chondrocytes propagated in microcarrier spinner culture, nasal chondrocytes expressed high levels of collagen type II mRNA, whereas collagen type I mRNA levels were low. Aggrecan mRNA was detectable and levels of de novo 35SO(4) incorporation were high. Chondrocytes immunostained intensely for collagen type II and keratan sulfate but did not stain for collagen type I. beta-1 integrin mRNA levels were high, and the protein was immunolocalized to regions of cell-to-cell or cell-to-microcarrier contact. The fact the chondrocytes expressed high levels of beta-1 integrin raises the possibility that this integrin molecule has a role in the maintenance of the chondrocytic phenotype.


Assuntos
Técnicas de Cultura de Células/instrumentação , Condrócitos/metabolismo , Proteínas da Matriz Extracelular , Integrina beta1/biossíntese , Septo Nasal/citologia , Agrecanas , Biomarcadores , Técnicas de Cultura de Células/métodos , Colágeno/biossíntese , Colágeno/genética , Perfilação da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Integrina beta1/genética , Sulfato de Queratano/biossíntese , Sulfato de Queratano/genética , Lectinas Tipo C , Masculino , Microesferas , Pessoa de Meia-Idade , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Proteoglicanas/biossíntese , Proteoglicanas/genética , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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