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1.
Refuat Hapeh Vehashinayim (1993) ; 31(3): 41-7, 62, 2014 Jul.
Artigo em Hebraico | MEDLINE | ID: mdl-25219100

RESUMO

Necrotizing Ulcerative Gingivitis (NUG) is an acute and rare (0.5-11% of the population) infectious disease of the gum tissue, which is characterized by ulceration and inflammation of the inter-dental gum tissue. NUG was documented by historians since the fourth century BC, most of the reports from the ancient world were in the context of illness among fighting troops, present studies of NUG in the modern world are still common among soldiers. NUG is associated with poor oral hygiene and weakening of the host, especially in immunocompromised patients, malnutrition and poor living conditions, as well as in the context of mental stress. NUG is more common in young adults, but reports of morbidity in young children with malnutrition in the background are not uncommon. NUG diagnosis is based on three essential symptoms: sore gums, bleeding gums and the most diagnostic characteristic, ulceration and necrosis of the interdental papillae. The disease is considered to have a clear initial infectious etiology, when the main bacteria, associated with the disease, include: Bacteroides intermedius and Fusobacterium sp. The infection involves anaerobic \ aerobic bacteria with a majority of Gram-negative bacteria. The treatment of NUG is based on combining mechanical removal of tartar with local and systemic delivery of antimicrobial agents. Adequate treatment usually prevent the progression of the disease and ulcer healing is expected in a few days. Nevertheless, lack of treatment can lead to deterioration in the form NUP to Noma.


Assuntos
Gengiva/patologia , Gengivite Ulcerativa Necrosante/patologia , Inflamação/patologia , Adulto , Fatores Etários , Criança , Progressão da Doença , Gengivite Ulcerativa Necrosante/epidemiologia , Gengivite Ulcerativa Necrosante/etiologia , Humanos
2.
Oral Dis ; 20(4): 386-94, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23730959

RESUMO

OBJECTIVES: To characterize demographic, clinical and serological parameters in recurrent aphthous stomatitis (RAS) patients and analyse their association with serum immunoglobulin E (IgE) levels. SUBJECTS AND METHODS: Forty-nine patients with RAS responded to a questionnaire that included demographic background, stress status, smoking habits, history and course of RAS episodes. They were also subjected to relevant laboratory tests, including determination of serum IgE levels. RESULTS: A familial history of RAS was reported by 47.9% of the patients, stress in the previous year by 51.1% and smoking by 18.4%. Non-Caucasian origin, familial history of RAS, stress and smoking were associated with increased severity of RAS episodes. Haematological deficiencies were observed in 18.7% of RAS patients. Average IgE levels were increased and were significantly associated with younger age, ≤12 years of schooling, female gender, RAS episode frequency of every 2 weeks , early onset of RAS episodes and elevated C reactive protein levels. CONCLUSION: Immunoglobulin E levels may be considered as part of the RAS patient's work-up. Further research is needed to identify biological mechanisms that account for the observed associations.


Assuntos
Imunoglobulina E/sangue , Estomatite Aftosa/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estomatite Aftosa/diagnóstico , Estomatite Aftosa/epidemiologia , Adulto Jovem
3.
J Hered ; 96(2): 124-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15618308

RESUMO

Crosses between the diploid Hylocereus polyrhizus, as the female parent, and the tetraploid Selenicereus megalanthus, as the male parent, yielded triploid and aneuploid hybrids. The fruits of these hybrids combined the attractive appearance of Hylocereus fruits with the delicious taste of S. megalanthus fruits. The aim of this work was to assess the fertility and breeding potential of the triploid and aneuploid hybrids with a view to developing an improved vine cactus crop. Pollen mother cells at metaphase I revealed univalents, bivalents, trivalents, and occasionally quadrivalents. Chromosome distribution at anaphase I revealed different classes of chromosome segregation as well as lagging chromosomes. At metaphase II, parallel and tripolar spindles were observed. The occurrence of triads was frequent, whereas dyads were rarely observed. Pollen stainability varied among the clones studied ranging from 9.8% to 18.6%. The diameters of the stained pollen grains varied widely, probably as a result of the number of chromosomes. Despite the allotriploid origin of our hybrids, functional female and male gametes were produced in considerable proportions, most likely as a result of balanced chromosome segregation. The triploid and aneuploid clones studied yielded viable seeds whose number per fruit was strongly dependent on the pollen donor.


Assuntos
Cactaceae/genética , Hibridização Genética , Ploidias , Cruzamento/métodos , Cactaceae/fisiologia , Ciclo Celular/fisiologia , Segregação de Cromossomos/fisiologia , Análise Citogenética , Fertilidade/genética , Frutas/fisiologia , Pólen/citologia , Pólen/genética
4.
J Hered ; 94(4): 329-33, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12920104

RESUMO

We performed reciprocal crosses between the tetraploid Selenicereus megalanthus and the diploid Hylocereus species, H. undatus and H. polyrhizus. S. megalanthus x H. undatus gave rise to viable hexaploids and 6x-aneuploid hybrids rather than to the expected triploids. No genuine hybrids were obtained in the reciprocal cross. The pollen diameter of the tetraploid S. megalanthus varied widely, indicating the occurrence of unreduced gametes, while that of H. undatus pollen was very uniform, indicating an extremely low frequency of unreduced gametes. This finding suggests that the hexaploids were formed by chromosome doubling after the formation of the hybrid triploid zygote rather than by fusion of unreduced gametes of the two species.


Assuntos
Cactaceae/genética , Hibridização Genética , Ploidias , Cruzamentos Genéticos , Hibridização in Situ Fluorescente , Metáfase/genética , Pólen/genética , Pólen/ultraestrutura
5.
Phytochemistry ; 58(8): 1209-12, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11738409

RESUMO

The presence of betacyanin pigments and their isoforms has been detected in the fruit of Hylocereus polyrhizus, a vine cactus native to South America. Along with the known betanin and phyllocactin (6'-O-malonylbetanin), a new betacyanin was structurally elucidated as betanidin 5-O-[6'-O-(3"-hydroxy-3"-methyl-glutaryl)-beta-D-glucopyranoside] (proposed trivial name hylocerenin) by means of electrospray MS/MS, HPLC, and NMR techniques.


Assuntos
Cactaceae/química , Indóis/química , Betacianinas , Frutas/química , Indóis/isolamento & purificação , Espectrometria de Massas
6.
Diabetologia ; 43(6): 809-13, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10907127

RESUMO

AIM/HYPOTHESIS: Electroacupuncture has been shown to induce a short-term hypoglycaemic effect in streptozotocin diabetic rats. We designed an experiment to investigate the effect of electroacupuncture in Psammomys obesus, a model of insulin resistance and non-insulin-dependent diabetes mellitus. METHODS: We divided 29 diabetic Psammomys randomly into three groups: abdominal electroacupuncture (real, n = 11), back electroacupuncture (placebo, n = 9) and control (anaesthesia, n = 9). Electroacupuncture was carried out on days 1, 3 and 5 of the experiment. During the first week of the experiment, blood glucose was tested three times on treatment days and once on the following days. Over the next 2 weeks, blood glucose was tested every other day. Animals were weighed at the same time of blood sampling. After 3 weeks, at the end of the experiment, blood was drawn for measurement of insulin, fructosamine, cholesterol and triglycerides. RESULTS: At day 5 (end of intervention), blood glucose (as per cent of primary concentrations, means +/- SE) was 57 +/- 10, 93 +/- 13 and 89 +/- 11 for the real, placebo and control groups respectively (p = 0.02). At day 8, blood glucose 68 +/- 14, 86 +/- 16 and 97 +/- 9 for the real, placebo and control groups respectively (p = 0.04). At day 22, blood glucose was 79 +/- 11, 85 +/- 15 and 131 +/- 2 for the real, placebo and control groups (p = 0.04). Comparison of the decline in blood glucose, throughout the 3 weeks, between the real and placebo groups by ANOVA was highly significant (p < 0.0001), the difference between the placebo and control groups at the same time was not significant (p > 0.05). Animal weight gain, serum insulin, fructosamine, cholesterol and triglycerides were not significantly different between real and placebo groups. CONCLUSION/INTERPRETATION: Electroacupuncture at special abdominal acupoints induces a sustained hypoglycaemic effect in diabetic Psammomys compared with electroacupuncture at non-specific points, without weight loss. No hypoinsulinaemic effect was shown in the real and placebo groups.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Eletroacupuntura , Hipoglicemia/etiologia , Análise de Variância , Animais , Glicemia/metabolismo , Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Modelos Animais de Doenças , Frutosamina/sangue , Gerbillinae , Insulina/sangue , Resistência à Insulina , Masculino , Ratos , Fatores de Tempo , Triglicerídeos/sangue
7.
Am J Bot ; 87(7): 1058-65, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10898783

RESUMO

Chromosome numbers and meiotic behavior are reported for the climbing cacti species Hylocereus undatus, Hylocereus polyrhizus, and Selenicereus megalanthus. The Hylocereus spp. are diploid (2n = 22), while S. megalanthus is a tetraploid (2n = 44). Irregular chromosome disjunction at anaphase I in pollen mother cells of S. megalanthus is probably the major cause of its reduced pollen viability and may contribute to low seed set, low number of viable seeds and, consequently, low fruit mass. A pollination study confirmed self-incompatibility in H. polyrhizus and a weakened incompatibility reaction in H. undatus and S. megalanthus. Major crossability barriers do not exist between the Hylocereus spp. investigated. Reciprocal intergeneric crosses were successful between Hylocereus spp. and S. megalanthus, suggesting that an Hylocereus sp. might be one of the diploid progenitors of the tetraploid S. megalanthus. The implications of the results on cacti nomenclature and systematics are briefly discussed.

8.
Theor Appl Genet ; 88(8): 914-6, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24186242

RESUMO

Independent spontaneous triploid tomato plants (Lycopersicon esculentum Mill.) were collected among diploid hybrids growing in commercial greenhouses. Ploidy levels were verified by counting chromosomes, and the donor of the double genome dose was determined by restriction fragment length polymorphism (RFLP) analysis. The TG101 probe, which is tightly linked to the Tm-2 (a) locus, revealed different restriction patterns between TMV-resistant and TMV-susceptible parent lines. The parent donor which provided two genomes to the triploid was identified by comparing the relative intensity of alleles in the triploid with that in the diploid. The results indicate that both parents can serve as a double genome donor.

9.
Plant Physiol ; 91: 738-43, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-11537462

RESUMO

Previous work (A Apelbaum et al. [1988] Plant Physiol 88: 996-998) has demonstrated binding of labeled spermidine (Spd) to a developmentally regulated 18 kilodalton protein in tobacco tissue cultures derived from thin surface layer explants. To assess the general importance of such Spd-protein complexes, we attempted bulk isolation from protoplasts of Petunia and oat (Avena sativa). In Petunia, as in tobacco, fed radioactive Spd is bound to protein, but in oat, Spd is first converted to 1,3,-diaminopropane (DAP), probably by polyamine oxidase action. In oat, binding of DAP to protein depends on age of donor leaf and conditions of illumination and temperature, and the extraction of the DAP-protein complex depends upon buffer and pH. The yield of the DAP-protein complex was maximized by extraction of frozen-thawed protoplasts with a pH 8.8 carbonate buffer containing SDS. Its molecular size, based on Sephacryl column fractionation of ammonium sulfate precipitated material, exceeded 45 kilodaltons. Bound Spd or DAP can be released from their complexes by the action of Pronase, but not DNAse, RNAse, or strong salt solutions, indicating covalent attachment to protein.


Assuntos
Avena/metabolismo , Proteínas de Plantas/metabolismo , Poliaminas/metabolismo , Protoplastos/metabolismo , Solanaceae/metabolismo , Avena/citologia , Avena/ultraestrutura , Diaminas/metabolismo , Concentração de Íons de Hidrogênio , Luz , Ligação Proteica , Protoplastos/ultraestrutura , Solanaceae/citologia , Solanaceae/ultraestrutura , Espermidina/metabolismo , Temperatura
10.
Plant Physiol ; 79(1): 28-33, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16664387

RESUMO

Coleoptile segments of oat (Avena sativa var Cayuse) and corn (Zea mays L. var Patriot) were incubated in different concentrations of calmodulin antagonists in the presence and absence of alpha-naphthaleneacetic acid. The calmodulin antgonists (chlorpromazine (CP), trifluoperazine, and fluphenazine) inhibited the auxin-induced elongation at 5 to 50 micromolar concentrations. Chlorpromazine sulfoxide, an analog of chlorpromazine, did not have significant effect on the elongation of oat and corn coleoptiles. A specific inhibitor of calmodulin N-(6-aminohexyl)5-chloro-1-naphthalenesulfonamide hydrochloride (W-7, a naphthalenesulfonamide derivative) inhibited coleoptile elongation, while its inactive analog N-(6-aminohexyl)-1-naphthalenesulfonamide hydrochloride (W-5) was ineffective at similar concentrations. During a 4-hour incubation period, coleoptile segments accumulated significant quantities of (3)H-CP. About 85 to 90% of auxin-induced growth was recovered after 4 hours of preincubation with CP or 12 hours with W-7 and transferring coleoptiles to buffer containing NAA. Leakage of amino acids from coleoptiles increased with increasing concentration of CP, showing a rapid and significant increase above 20 micromolar CP. The amount of amino acids released in the presence of W-7 and W-5 was significantly lower than the amount released in the presence of CP. Both W-5 and W-7 increased amino acid release but only W-7 inhibited auxin-induced growth. Calmodulin activity measured by phosphodiesterase activation did not differ significantly between auxin-treated and control coleoptile segments. These results suggest the possible involvement of calmodulin in auxin-induced coleoptile elongation.

11.
Steroids ; 45(3-4): 277-87, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3841741

RESUMO

The suggestion has been made that the aromatase system from human placenta converting testosterone to estradiol-17 beta is localized to some extent in the mitochondrial fraction in addition to its microsomal origin. By comparing the characteristics of the "mitochondrial" aromatase with certain particularities of other mitochondrial or microsomal enzymes, especially those functioning in steroid hydroxylation, the conclusion has been reached that the mitochondrial and the microsomal aromatases are one and the same. Thus, in response to ultrasound treatment and in response to the addition of specific cofactors, the mitochondrial aromatase showed all the characteristics attributed to microsomal enzymes and was indistinguishable from the microsomal aromatase.


Assuntos
Aromatase/metabolismo , Mitocôndrias/enzimologia , Placenta/enzimologia , Glândulas Suprarrenais/enzimologia , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Estudos de Avaliação como Assunto , Feminino , Humanos , Microssomos/enzimologia , Microssomos/ultraestrutura , Mitocôndrias/ultraestrutura , Gravidez , Ratos , Ratos Endogâmicos , Esteroide Hidroxilases/metabolismo , Ultrassom
12.
Plant Physiol ; 74(2): 385-8, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16663427

RESUMO

During the life cycle of Chlorella vulgaris Beijerinck var vulgaris fa. vulgaris growing synchronously, the specific activity of ornithine decarboxylase peaked at the 2nd hour of the cycle, whereas that of arginine decarboxylase changed only slightly, increasing towards the end of the cycle. The endogenous level of putrescine and spermidine on a per cell basis increased gradually up to the 8th hour of the cycle, and declined thereafter. Thus, the peak of ornithine decarboxylase activity and the polyamine increase preceded both DNA replication (which took place between the 6th and 8th hours of the cycle) and autospore release (which started at the 8th hour). A 2-fold increase in the light intensity caused doubling of the DNA content, resulting in doubling of the number of autospores per mother cell. It also brought about a 2-fold increase in the specific activity of ornithine decarboxylase and polyamine content, the peaks being at the same hour of the cycle under high and low light intensities. The increase in cell number and polyamine content in a Chlorella culture grown under high light intensity was inhibited by alpha-difluoromethyl ornithine, a specific inhibitor of ornithine decarboxylase, this inhibition being partially reversed by putrescine.It is suggested that in C. vulgaris the sequence of events which relates polyamine biosynthesis to cell division is as follows: increased ornithine decarboxylase activity, accumulation of polyamines, DNA replication, and autospore release.

13.
Plant Physiol ; 70(2): 540-3, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16662530

RESUMO

The apparent association of ornithine decarboxylase (ODC) with rapid cell proliferation in developing tomato (Lycopersicon esculentum Mill. cv. Pearson ms-35) fruits has been previously described. Further evidence is provided by the use of two ODC inhibitors, alpha-difluoromethylornithine (alpha-DFMO) and alpha-methylornithine (alpha-MO). Fruit development was inhibited by these inhibitors if applied during the period of intensive cell division. When applied in vitro, the two inhibitors were shown to inhibit the activity of ODC but not that of arginine decarboxylase (ADC). When applied in vivo, alpha-DFMO, a catalytic irreversible inhibitor, caused 97.1% reduction of ODC activity in the dialyzed extract from the treated ovaries, while it had no effect on ADC. On the other hand, alpha-MO, a reversible inhibitor, did not reduce the activity of these two enzymes in the dialyzed extracts when applied in vivo. The dialysis procedure probably removed alpha-MO from the enzyme fraction. Putrescine, the product of both ODC and ADC, alleviated the inhibition of fruit development but did not restore ODC activity to the control level. These results suggest that in the young developing tomato fruit, ODC is the enzyme responsible for the synthesis of putrescine, which is essential for the early stages of fruit development. The reduced activity of ODC elicited by putrescine suggests a mechanism of feedback regulation by enzyme repression or release of an ODC anti-enzyme.

14.
Plant Physiol ; 70(2): 544-6, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16662531

RESUMO

Ornithine decarboxylase and arginine decarboxylase activities were measured in roots and buds of tomato (Lycopersicon esculentum Mill. cv. Pearson ms-35) and potato (Solanum tuberosum cv. Desire) plants. In both tomato and potato, the activity of ornithine decarboxylase was the highest at the root tip, decreasing proximally. The same was true for potato buds. In vegetative buds of tomato, the highest activity was found in the youngest leaves. The older the leaf, the lower was orithine decarboxylase activity. Arginine decarboxylase, on the other hand, did not display a similar gradient. These findings are in accordance with the suggestion that in tomato and potato elevated ornithine decarboxylase activity is associated with intense mitotic activity.

15.
Plant Physiol ; 69(4): 966-70, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16662327

RESUMO

Tomato (Lycopersicon esculentum Mill) plants from various cultivars growing on half-strength Hoagland solution were exposed at anthesis to 3 or 6 grams per liter NaCl. Salinity shortened the time of fruit development by 4 to 15%. Fruits of salt-treated plants were smaller and tasted better than did fruits of control plants. This result was obtained both for ripe fruits tested on the day of picking and for those picked at 100% development and allowed to ripen at room temperature for 9 days. Percentage of dry weight, total soluble solids, and titratable acidity; content of reducing sugars, Cl(-), Na(+), and various pericarp pigments; and electrical conductivity of the juice were higher in fruits of saline-treated plants than they were in those of control plants, while the pH was lower. Ethylene and CO(2) evolution rates during ripening; as well as the activities of pectin methyl esterase, polymethylgalacturonase, and polygalacturonase; were also higher in fruits of the saline-treated plants. The treatment with 6 grams per liter NaCl shortened the fruit shelf life considerably.

16.
Biochem J ; 201(2): 373-6, 1982 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-7082296

RESUMO

Some characteristics of L-ornithine decarboxylase of tomato ovaries and tobacco cells are described. The enzyme has a pH optimum of 8.0. It requires pyridoxal phosphate and thiol reagent (dithiothreitol) for activity. It is specific for L-ornithine and has an apparent Km of 1.4 X 10-4 M. It has an apparent molecular weight of 107000. Putrescine inhibited the activity in vitro. Spermidine and spermine also inhibit the enzyme, but less effectively. It is concluded that the enzyme is similar to that of mammalian origin and likewise fulfils a function related to cell proliferation.


Assuntos
Carboxiliases/metabolismo , Ornitina Descarboxilase/metabolismo , Plantas/enzimologia , Aminoácidos/metabolismo , Ditiotreitol/metabolismo , Inibidores da Ornitina Descarboxilase , Plantas Tóxicas , Poliaminas/farmacologia , Fosfato de Piridoxal/metabolismo , Nicotiana/enzimologia
17.
Plant Physiol ; 69(2): 497-501, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16662236

RESUMO

Tomato (Lycopersicon esculentum Mill) plants of the nonripening mutant nor, the ripening-inhibited mutant rin, and the normal cultivar ;Rutgers' were grown in nutrient solution supplemented with 3 grams per liter NaCl from the time of anthesis. In plants treated with NaCl, all the ripening parameters of the fruits of the nor mutant increased, but those of the rin mutant did not. The ripening of the fruits of the NaCl-treated nor plants was characterized by the development of a red color and taste, increased pectolytic activity, and increased evolution of CO(2) and ethylene. These changes do not normally take place in nor under control conditions. The values of these ripening parameters in nor were lower than those of the normal Rutgers fruits. In addition, both in nor and rin and in the normal variety, exposure of the plants to NaCl shortened the developmental period of the fruit, decreased the fruit size, and increased the concentrations of total soluble solids, Na(+), Cl(-), reducing sugars, and titratable acids in the fruit. The role of NaCl in overcoming the inability of nor to ripen is discussed.

19.
Vox Sang ; 37(4): 193-200, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-386611

RESUMO

Pregnancy sera were found to react differently when screened simultaneously with adenoid and peripheral blood lymphocytes (PBL) obtained from the same individual. Some of the reactions were attributed to the higher sensitivity of adenoid lymphocytes to a low titer HLA or Ia antibody, while others were shown to be due to the expression of DRw (Ia-like) antigens on both T and B lymphocytes separated from adenoids. Positive reactions specific to adenoid lymphocytes, or manifested only following anti-beta2-microglobulin (a-beta2-m) treatment, suggest the presence of antigens other than HLA or Ia on the cell membrane. Unmasking of antigenic sites by the a-beta2-m capping process and rearrangement of the membrane structure may also contribute to the observed phenomena.


Assuntos
Tonsila Faríngea/imunologia , Antígenos de Superfície , Linfócitos B/imunologia , Antígenos HLA , Linfócitos T/imunologia , Animais , Criança , Pré-Escolar , Citotoxicidade Imunológica , Feminino , Teste de Histocompatibilidade , Humanos , Soros Imunes/farmacologia , Gravidez , Perus , Microglobulina beta-2/imunologia
20.
Planta ; 130(2): 223-4, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24424603

RESUMO

Fruit extracts of non-ripening tomato Lycopersicon esculentum Mill strain rin contain extra protein band comparing with the normal ripening cultivar Rutgers. Another band exists in both varieties, but disappears in Rutgers at the onset of ripening. The existence of a proteinaceous ripening inhibitor is suggested.

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