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1.
Phys Rev Lett ; 132(16): 163601, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701452

RESUMO

We theoretically investigate prospects for the creation of nonclassical spin states in trapped ion arrays by coupling to a squeezed state of the collective motion of the ions. The correlations of the generated spin states can be tailored for quantum-enhanced sensing of global or differential rotations of subensembles of the spins by working with specific vibrational modes of the ion array. We propose a pair of protocols to utilize the generated states and demonstrate their viability even for small systems, while assessing limitations imposed by spin-motion entanglement and technical noise. Our work suggests new opportunities for the preparation of many-body states with tailored correlations for quantum-enhanced metrology in spin-boson systems.

2.
Lett Appl Microbiol ; 72(1): 41-52, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32910828

RESUMO

The use of rosemary essential oil (RO) and its combination with nisin (RO+N) in preventing the multiplication of Alicyclobacillus acidoterrestris in orange juice was evaluated. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for RO were both 125 µg ml-1 while RO+N displayed a synergistic effect. The use of RO and RO+N at concentrations of 1, 4 and 8× MIC in orange juice for 96 h was evaluated in terms of their sporicidal effectiveness. With regard to the action against A. acidoterrestris spores, RO at 8× MIC was sporostatic, whereas RO+N at 1× MIC was sporicidal. Morphological changes in the structure of the micro-organism after treatment were also observed by microscopy. Furthermore, flow cytometric analysis showed that most cells were damaged or killed after treatment. In general, the antioxidant activity after addition of RO+N decreased with time. The results demonstrate that using the combination of RO and nisin can prevent the A. acidoterrestris growth in orange juice.


Assuntos
Alicyclobacillus/crescimento & desenvolvimento , Antibacterianos/farmacologia , Sucos de Frutas e Vegetais/microbiologia , Nisina/farmacologia , Óleos Voláteis/farmacologia , Rosmarinus/química , Alicyclobacillus/efeitos dos fármacos , Citrus sinensis
4.
Eur J Clin Microbiol Infect Dis ; 31(10): 2513-27, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22581304

RESUMO

Candida albicans, C. glabrata, C. parapsilosis, and C. tropicalis are able to form biofilms on virtually any biomaterial implanted in a human host. Biofilms are a primary cause of mortality in immunocompromised and hospitalized patients, as they cause recurrent and invasive candidiasis, which is difficult to eradicate. This is due to the fact that the biofilm cells show high resistance to antifungal treatments and the host defense mechanisms, and exhibit an excellent ability to adhere to biomaterials. Elucidation of the mechanisms of antifungal resistance in Candida biofilms is of unquestionable importance; therefore, this review analyzes both the chemical composition of biomaterials used to fabricate the medical devices, as well as the Candida genes and proteins that confer drug resistance.


Assuntos
Antifúngicos/farmacologia , Materiais Biocompatíveis/farmacologia , Biofilmes , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Antifúngicos/química , Materiais Biocompatíveis/química , Candida/genética , Candida/fisiologia , Candidíase Invasiva/epidemiologia , Candidíase Invasiva/microbiologia , Adesão Celular , Membrana Celular/metabolismo , Farmacorresistência Fúngica , Fluconazol/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Próteses e Implantes/microbiologia
5.
Int J Clin Pract ; 65(6): 669-73, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21564439

RESUMO

BACKGROUND: An association between prolactin-secreting pituitary adenomas and anaemia in male patients has been recently reported. Our aim has been to evaluate the prevalence of anaemia in men with prolactinomas and to assess the relationships between haemoglobin concentrations and pituitary function at diagnosis in these patients. METHODS: In a retrospective analysis, 26 male patients with prolactinomas (22 macroprolactinomas and 4 microprolactinomas) were studied. Blood haemoglobin concentration, haematocrit value and baseline hormonal levels were collected at the time of prolactinoma diagnosis. The presence or absence of partial or total hypopituitarism was also evaluated at diagnosis. Logistic regression analysis was used to assess the presence of anaemia as a function of serum hormone concentrations and pituitary dysfunction. RESULTS: Patient bearing macroprolactinomas showed significant lower haemoglobin concentrations than those found in patients with microprolactinomas (13.5 ± 1.2 g/dl vs. 15.1 ± 0.9 g/dl, p < 0.05). Anaemia (haemoglobin < 13 g/dl) was present in nine (34.6%) patients, all of them with macroprolactinomas. The degree of anaemia was mild (haemoglobin > 11 g/dl) in all patients. No correlation between haemoglobin and serum prolactin was found. Haemoglobin concentration was significantly lower in men with hypogonadism (n = 14) than in eugonadal men. Haemoglobin value was also significantly lower in patients with total hypopituitarism in comparison with patients with partial hypopituitarism (12.4 ± 1.0 g/dl, n = 7 vs. 14.0 ± 1.2 g/dl, n = 13, p = 0.007). The number of affected pituitary axes was found to be related with the presence of anaemia. Logistic regression analysis showed that anaemia was related with FT4 (OR 0.23; 95% CI 0.06-0.81, p = 0.02), cortisol (OR 0.81; 95% CI 0.68-0.96, p= 0.02) and the presence of hypopituitarism (OR 20.0; 95% CI 1.68-238.63, p = 0.02). CONCLUSIONS: Anaemia was found in about a third of men with prolactinomas. Our results also suggest that the presence of anaemia in these patients seems to be associated with panhypopituitarism.


Assuntos
Anemia/etiologia , Neoplasias Hipofisárias/complicações , Prolactinoma/complicações , Adulto , Hemoglobinas/metabolismo , Humanos , Hipogonadismo/etiologia , Hipopituitarismo/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/sangue , Prolactinoma/sangue , Estudos Retrospectivos , Adulto Jovem
6.
Sci Adv ; 6(26): eaba7509, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32637615

RESUMO

Mitochondrial respiratory complexes assemble into supercomplexes (SC). Q-respirasome (III2 + IV) requires the supercomplex assembly factor (SCAF1) protein. The role of this factor in the N-respirasome (I + III2 + IV) and the physiological role of SCs are controversial. Here, we study C57BL/6J mice harboring nonfunctional SCAF1, the full knockout for SCAF1, or the wild-type version of the protein and found that exercise performance is SCAF1 dependent. By combining quantitative data-independent proteomics, 2D Blue native gel electrophoresis, and functional analysis of enriched respirasome fractions, we show that SCAF1 confers structural attachment between III2 and IV within the N-respirasome, increases NADH-dependent respiration, and reduces reactive oxygen species (ROS). Furthermore, the expression of AOX in cells and mice confirms that CI-CIII superassembly segments the CoQ in two pools and modulates CI-NADH oxidative capacity.

7.
Braz J Med Biol Res ; 52(9): e8224, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482975

RESUMO

Leishmaniasis is a neglected disease that affects a large part of the world population. Knowing the sand fly fauna of a region is of fundamental importance for guiding health surveillance actions related to the prevention and control of leishmaniasis. A total of 86 specimens of sand flies (60 females and 26 males) were collected. Using the classification proposed by Galati (2003), the following species were identified: Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1920), Evandromyia cortelezzi (Brethes, 1923), Ev. sallesi (Galvão & Coutinho, 1939), Nyssomyia whitmani (Atunes & Coutinho, 1939), Psathyromyia lutziana (Costa Lima, 1932), Ev. lenti (Mangabeira, 1938), Brumptomyia sp. (França and Parrot, 1921), and Pressatia sp. (Mangabeira, 1942). Using PCR with internal transcribed spacer target to identify infected sand flies, five Lu. longipalpis females were infected with Leishmania spp. Despite the small number of specimens collected, considerable species diversity was found in the study area.


Assuntos
Insetos Vetores/classificação , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Psychodidae/classificação , Psychodidae/parasitologia , Animais , Brasil , DNA Espaçador Ribossômico/genética , Feminino , Leishmania/genética , Leishmaniose/transmissão , Masculino , Reação em Cadeia da Polimerase , RNA de Protozoário/genética
8.
Climacteric ; 11(6): 483-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991075

RESUMO

OBJECTIVE: The objective of this study was to evaluate the effects of raloxifene on the weight and epithelial thickness of the urethra of castrated female rats. METHODS: Forty castrated female rats were randomly separated into two groups: group I (control, n = 20) received only the vehicle, and group II (raloxifene, n = 20) received 750 microg/day of raloxifene for 30 days. On the 31st day, the animals were sacrificed and the urethras were removed for the study. A model for categorical data using the weighted minimum mean square error method and Student's t test were used for the data analysis (p < 0.05). RESULTS: The mean weights of the urethras in groups I and II were 22 +/- 1.6 mg and 24 +/- 1.7 mg, respectively (p = 0.371). There was an increase in the mean epithelial thickness of the distal segments in group II compared to group I (50.7 +/- 1.9 microm vs. 45.3 +/- 1.6 microm, respectively) (p < 0.04). No statistically significant difference was found in the mean epithelial thickness of the proximal urethra between the two groups (p = 0.187). CONCLUSION: Raloxifene administered to castrated female rats for 30 days increased the distal urethral epithelial thickness and did not alter the weight of the urethra.


Assuntos
Cloridrato de Raloxifeno/farmacologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Uretra/efeitos dos fármacos , Bexiga Urinária/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Feminino , Ovariectomia , Pós-Menopausa/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Incontinência Urinária/prevenção & controle
9.
Int J Audiol ; 47(3): 115-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18307091

RESUMO

The purpose of this retrospective study is to examine the possible association between iris pigmentation and susceptibility to noise-induced hearing loss in 2407 noise-exposed workers. The workers were between 16 to 65 years of age and were exposed to 2 to 42 years of work-related noise. Results demonstrated that dark-eyed workers presented a greater percentage of normal pure-tone thresholds than fair-eyed workers. Fair-eyed workers had threshold averages of 25.1 dB (right ear) and 26.0 dB (left ear) at 3, 4, and 6 kHz, which were significantly worse than workers with dark irises, with threshold averages of 15.8 dB and 17.2 dB in the right and left ear, respectively (p<0.01). Fair-eyed workers with less than 10 years of noise exposure had the same audiometric pattern as the dark-eyed workers exposed for more than 10 years. Workers not exposed to noise did not present significant differences in their audiometric pattern as a function of eye colour. These results suggest that iris pigmentation may be an additional indication of susceptibility to noise-induced hearing loss.


Assuntos
Perda Auditiva Provocada por Ruído/etiologia , Iris , Epitélio Pigmentado Ocular , Adolescente , Adulto , Idoso , Audiometria de Tons Puros , Biomarcadores , Estudos Transversais , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ruído Ocupacional/efeitos adversos , Exposição Ocupacional/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo
11.
Plant Dis ; 102(10): 1965-1972, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30265221

RESUMO

Big-leaf mahogany (Swietenia macrophylla) is valued for its high-quality wood and use in urban landscapes in Mexico. During surveys of mango-producing areas in the central western region of Mexico, symptoms of malformation, the most important disease of mango in the area, were observed on big-leaf mahogany trees. The objectives of this research were to describe this new disease and determine its cause. Symptoms on big-leaf mahogany at four sites in Michoacán, Mexico resembled those of the vegetative phase of mango malformation, including compact, bunched growth of apical and lateral buds, with greatly shortened internodes and small leaves that curved back toward the supporting stem. Of 163 isolates that were recovered from symptomatic tissues, most were identified as Fusarium pseudocircinatum (n = 121) and F. mexicanum (n = 39) using molecular systematic data; two isolates represented unnamed phylospecies within the F. incarnatum-equiseti species complex (FIESC 20-d and FIESC 37-a) and another was in the F. solani species complex (FSSC 25-m). However, only F. mexicanum and F. pseudocircinatum induced malformation symptoms on 14-day-old seedlings of big-leaf mahogany. The results indicate that F. mexicanum and F. pseudocircinatum, previously reported in Mexico as causal agents of mango malformation disease, also affect big-leaf mahogany. This is the first report of this new disease and the first time that F. mexicanum was shown to affect a host other than mango.


Assuntos
Fusarium/isolamento & purificação , Fusarium/patogenicidade , Meliaceae/microbiologia , Doenças das Plantas/microbiologia , DNA Fúngico/genética , Fusarium/genética , México , Tipagem de Sequências Multilocus , Filogenia , Plântula/microbiologia
12.
Infect Genet Evol ; 6(5): 361-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16461017

RESUMO

Polymorphism in SLC11A1 has been implicated in host susceptibility to tuberculosis. We have studied associations between INT4, D543N, and 3'UTR polymorphisms of SLC11A1 and different clinical forms of TB. Analysis used 507 patients with pulmonary TB, 123 with extra pulmonary TB and 513 controls. INT4 and D543N showed allelic association with pulmonary TB (P=0.02 and 0.03 respectively). INT4-D543N-3'UTR haplotypes showed an association with pulmonary TB (P=0.03). No association of SLC11A1 with miliary TB was observed, and a possible association of D543N to the pleural form (P=0.08) was suggested. These results support association between SLC11A1 and TB, particularly to the common pulmonary form.


Assuntos
Proteínas de Transporte de Cátions/genética , Predisposição Genética para Doença , Polimorfismo Genético , Tuberculose Pulmonar/genética , Adolescente , Adulto , Genótipo , Haplótipos , Humanos , Masculino , Peru/epidemiologia , Tuberculose Pulmonar/epidemiologia
13.
Endocrinology ; 117(6): 2483-9, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2415348

RESUMO

The pattern of alpha MSH release during immobilization stress in ovariectomized rats was determined and correlated with that of plasma PRL and LH. Stress induced a marked elevation in plasma immunoreactive alpha MSH, with a time course identical to that of plasma PRL. The increment in plasma PRL was greater than that in plasma alpha MSH. Plasma LH was markedly lowered by stress. Analysis of pituitary and hypothalamic alpha MSH indicated a significant (P less than 0.05) increase in the neurointermediate lobe and anterior lobe content of alpha MSH. The alpha MSH content in the hypothalamus was lowered by stress when expressed as tissue content (P less than 0.025), although no significant differences in content in this area were detected when the results were expressed in terms of tissue protein. Stress induced a marked increase (P less than 0.01) in the median eminence levels of alpha MSH. Intraventricular (third ventricle) injection of the gamma-globulin fraction of a specific antiserum raised against alpha MSH increased basal PRL levels (P less than 0.025) and prevented the decline in plasma PRL that occurred 60 min after the onset of stress in the normal rabbit serum-injected rats. The stress-induced suppression of plasma LH was attenuated and delayed by the administration of alpha MSH antibodies. In conclusion, alpha MSH of brain origin is released during stress and is involved in lowering plasma PRL to basal levels and producing a partial suppression of plasma LH.


Assuntos
Hormônio Luteinizante/sangue , Hormônios Estimuladores de Melanócitos/sangue , Prolactina/sangue , Estresse Fisiológico/metabolismo , Animais , Feminino , Hipotálamo/análise , Soros Imunes , Injeções Intraventriculares , Hormônios Estimuladores de Melanócitos/imunologia , Hipófise/análise , Ratos , Ratos Endogâmicos , Restrição Física , Fatores de Tempo , gama-Globulinas/administração & dosagem , gama-Globulinas/farmacologia
14.
Mol Biochem Parasitol ; 52(1): 53-62, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1625707

RESUMO

Chitinase activity was measured in extracts of Entamoeba invadens cells as a function of time of encystation in axenic conditions using 4-MU(Ch)3 as substrate. Encystment was paralleled by chitinase activity which showed a peak after about 72 h of cultivation where cysts accounted for 63% of cell population. Thereafter, activity fell off rapidly, whereas encystment continued, reaching 80% at the end of the experiment (96 h). Comparison of activity between cysts and the total cell population in 48- and 72-h-old encysting cultures suggested that chitinase may start to accumulate in the pre-cyst forms. About 70% of the enzyme was recovered in the supernatant following low-speed centrifugation of whole extracts. Most of this activity represented soluble chitinase since it was not sedimented by further centrifugation at 105,000 x g. A minor proportion of enzyme activity remained associated to the buffer-washed, high-speed sediment. In addition to 4-MU(Ch)3, chitinase activity was also measured following the hydrolysis of other substrates such as nascent, preformed or colloidal chitin. Like other chitinases, the cyst enzyme preferred nascent over preformed chitin as substrate. Digestion of the former yielded GlcNAc and minor amounts of (GlcNAc)2 as products. Allosamidin strongly inhibited hydrolysis of the fluorogenic substrate by the amebic chitinase in vitro with a Ki of 0.065 microM. IC50 values were 0.085 microM and 0.16 microM at 5 microM and 10 microM 4-MU(Ch)3, respectively. When added to the axenic medium, the drug markedly retarded encystment though it was partially recovered after longer periods of incubation.


Assuntos
Acetilglucosamina/análogos & derivados , Quitinases/metabolismo , Entamoeba/enzimologia , Trissacarídeos/farmacologia , Acetilglucosamina/farmacologia , Animais , Quitina/metabolismo , Quitinases/antagonistas & inibidores , Entamoeba/crescimento & desenvolvimento , Hidrólise , Cinética , Especificidade por Substrato
15.
Int J Parasitol ; 23(7): 847-52, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8314367

RESUMO

Growth of E. invadens was paralleled by a concomitant increase in ornithine decarboxylase activity which peaked after 5 days of cultivation in TYI-S-33 medium. Over this period, enzyme activity increased about nine-fold with respect to that present at the start of incubation. Thereafter and coinciding with the onset of the stationary growth phase, enzyme activity started to decline reaching trace levels after 8 days of cultivation. Most of the enzyme remained soluble following centrifugation of amoeba homogenates at 105,000 g. alpha-Difluoromethylornithine failed to affect ornithine decarboxylase activity in vitro and amoeba growth. The enzyme was markedly inhibited by polyamines (putrescine, spermidine and spermine) and 1,4-diamino-2-butanone, a putrescine-analog. The latter arrested proliferation of cells, an effect that could not be reversed by polyamines which by themselves also inhibited growth to a low but significant extent. Our results indicate that polyamine biosynthesis from ornithine is required for growth of E. invadens and that this function is rapidly abolished following entry into the stationary growth phase.


Assuntos
Entamoeba/enzimologia , Ornitina Descarboxilase/biossíntese , Animais , Eflornitina/farmacologia , Entamoeba/efeitos dos fármacos , Entamoeba/crescimento & desenvolvimento , Ornitina Descarboxilase/efeitos dos fármacos , Poliaminas/farmacologia , p-Dimetilaminoazobenzeno/farmacologia
16.
Int J Parasitol ; 21(3): 373-5, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1894436

RESUMO

A simplified and reliable method to quantify Entamoeba histolytica cytotoxicity was standardized. Mice spleen leucocytes were utilized as target cells. Interaction time was reduced to 1 h by pelleting interacting cells. To assess target-cell killing by amoebae, a nigrosine exclusion test was employed. Fixation with glutaraldehyde stabilized the percentage of stained target cells. Similar results were obtained when cytotoxicity of the E. histolytica HM1 strain was tested by the traditional and proposed methods. The new method allowed quantification of the contribution of cytolysis and cytophagocytosis to amoebic cytotoxicity. It was also demonstrated that uncloned E. histolytica HM1 strain is a heterogeneous population with respect to cytotoxicity expression.


Assuntos
Entamoeba histolytica/fisiologia , Baço/parasitologia , Animais , Células Cultivadas , Leucócitos/imunologia , Leucócitos/parasitologia , Camundongos , Fagocitose , Baço/citologia
17.
Int J Parasitol ; 26(3): 253-60, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8786214

RESUMO

Multiplication of E. histolytica was accompanied by a parallel increase in ornithine decarboxylase (ODC) specific activity up to 72 h of cultivation in TYI-S-33 medium. Thereafter, activity rapidly decayed whereas growth continued for another 24 h before entering into the stationary growth phase. ODC was very unstable. Partial purification (14-fold) of the enzyme was achieved by a three-step procedure involving high-speed centrifugation, gel filtration and adsorption to hydroxylapatite. The partially purified enzyme (Mr 211 kDa) revealed maximum activity at pH 8.5-9.0 and a sigmoidal response to substrate concentration. An S0.5 value of 1.0 mM ornithine was estimated. Although ODC did not exhibit an absolute dependence on pyridoxal phosphate (PLP), addition of PLP increased catalytic activity about 4-fold, with an S0.5 value of 45 microM. Evolution of 14CO2 from ornithine was markedly inhibited by polyamines in the following increasing order of effectiveness: putrescine > spermidine > spermine. The substrate analogs alpha-methylornithine and alpha-difluoromethylornithine had no effect on enzyme activity and cell growth. In contrast, 1,3-diaminopropane and 2,4-diamino-2-butanone, 2 putrescine analogs, severely inhibited both enzyme activity and amoeba multiplication. Results are discussed in terms of the role of ODC in the amoeba proliferation.


Assuntos
Entamoeba histolytica/enzimologia , Ornitina Descarboxilase/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Divisão Celular , Ornitina Descarboxilase/isolamento & purificação , Inibidores da Ornitina Descarboxilase , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/isolamento & purificação , Putrescina/farmacologia , Espermidina/farmacologia , Espermina/farmacologia
18.
Int J Parasitol ; 28(9): 1333-40, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9770617

RESUMO

Sequential incubation of a mixed membrane fraction isolated from Entamoeba histolytica trophozoites with the nonionic detergents Brij 35 and Igepal CA-630 rendered a soluble fraction with the ability to transfer N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to dolichol phosphate to form a lipid saccharide that was identified as a mixture of dolichol-P-P-GlcNAc and dolichol-P-P-(GlcNAc)2 as follows. (a) The reaction occurred only in the presence of exogenously added dolichol phosphate and was strongly inhibited by tunicamycin and amphomycin; (b) Over 90% of the aminosugar moiety of the lipid saccharide was released by mild acid hydrolysis and was identified as a mixture of GlcNAc and diacetylchitobiose [(GlcNAc)2]; (c) Time course experiments revealed that dolichol-P-P-(GlcNAc)2 accumulated at the expense of a parallel decrease in dolichol-P-P-GlcNAc revealing the tandem operation of UDPGlcNAc:dolichol-P GlcNAc-1-P transferase and UDPGlcNAc:dolichol-P GlcNAc transferase. Mg2+ and to a lower extent Mn2+ were required for catalytic activity and were optimal at 2.5 mM and 1.25 mM, respectively. Common phospholipids with different head groups failed to increase catalytic activity and phosphatidylglycerol was inhibitory. At low concentration, nucleotides such as ATP, GMP and GTP brought about stimulations of 24-54% but higher concentrations were inhibitory. Others were inhibitory at all concentrations the strongest being those containing a uridine base.


Assuntos
Acetilglucosamina/metabolismo , Asparagina/metabolismo , Entamoeba histolytica/metabolismo , Glicólise/fisiologia , N-Acetilglucosaminiltransferases/metabolismo , Oligossacarídeos/biossíntese , Monossacarídeos de Poli-Isoprenil Fosfato/metabolismo , Animais , Antibacterianos/farmacologia , Cátions Bivalentes/administração & dosagem , Cromatografia em Papel , Fosfatos de Dolicol/metabolismo , Lipopeptídeos , Magnésio/administração & dosagem , Manganês/administração & dosagem , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Oligopeptídeos/farmacologia , Polidocanol , Polietilenoglicóis/metabolismo , Tensoativos/metabolismo , Fatores de Tempo , Tunicamicina/farmacologia
19.
Peptides ; 6(3): 503-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4070018

RESUMO

Circulating levels and tissue content of alpha-MSH were measured on the morning of various days of the estrous cycle, and on the afternoon of proestrus in freely moving conscious rats. No surges of alpha-MSH were detected by RIA in the morning of various days of the cycle. The neurointermediate lobe content of alpha-MSH was slightly elevated on diestrus 1 as compared to the levels on diestrus 11 and proestrus but not to estrous levels. No changes in alpha-MSH content were detected in the anterior pituitary, the median eminence, mediobasal hypothalamus and the preoptic area at various stages of the estrous cycle. Plasma alpha-MSH levels were slightly elevated at 1500 hr of proestrus which was followed three hours later by a decline. This profile of plasma alpha-MSH on the afternoon of proestrus was reproduced by the SC administration of estradiol benzoate to long-term ovariectomized rats. These data suggest that, contrary to the results obtained by bioassay of alpha-MSH no surges of alpha-MSH occur on any day of the cycle, although a slight elevation on the afternoon of proestrus was detected. The altered pattern of release of this peptide on the afternoon of proestrus may be induced by estrogen.


Assuntos
Estradiol/farmacologia , Estro , Hormônios Estimuladores de Melanócitos/metabolismo , Animais , Feminino , Hipotálamo Médio/metabolismo , Hormônio Luteinizante/sangue , Eminência Mediana/metabolismo , Hormônios Estimuladores de Melanócitos/sangue , Ovariectomia , Hipófise/metabolismo , Adeno-Hipófise/metabolismo , Área Pré-Óptica/metabolismo , Prolactina/sangue , Ratos , Núcleo Supraquiasmático/metabolismo
20.
Brain Res ; 384(1): 11-6, 1986 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-3024775

RESUMO

Many experiments have been performed to evaluate the physiological role of catecholaminergic mechanisms in gonadotropin release. The purpose of the present study was to determine the concentration of beta-adrenoreceptors in the remaining (right) cerebral cortex and in right and left hypothalamic halves of hemi-decorticated female rats which exhibited elevated plasma gonadotropin levels as observed previously. The density of beta-receptors was measured using a high-affinity beta-adrenergic ligand, iodocyanopindolol (ICYP). Scatchard estimates were obtained for maximum binding (Bmax fmol/mg of tissues) from pooled cerebral cortical and hypothalamic tissue of animals under several experimental conditions after hemi-decortication and sham operation. There was an increase in beta-adrenoreceptor density in the remaining (right) cerebral cortex at all times examined in hemi-decorticate in comparison with the sham-operated animals (7 days, +10.9%; 21 days, +8.4%; 90 days, +22%; and 90 days plus ovariectomy, +34.8%). The number of beta-adrenoreceptors in the right hypothalamic half in hemi-decorticates decreased at 21 days (-42.20%) and then increased at 90 days (+76.63%) and 90 days plus ovariectomy (+51.75%) when compared with the left hypothalamic half. At the same time there were no significant changes in the sham-operated animals when comparing the receptor density in the right and left hypothalamic halves, respectively. Thus, our results suggest a direct or indirect adrenergic pathway by which the left cortex can influence the right cortex and a crossed pathway to the contralateral hypothalamus changing adrenergic activity which can alter the beta-adrenergic receptor binding capacity in the hypothalamus.


Assuntos
Córtex Cerebral/fisiologia , Lateralidade Funcional/fisiologia , Hipotálamo/fisiologia , Receptores Adrenérgicos beta/fisiologia , Animais , Córtex Cerebral/análise , Córtex Cerebral/ultraestrutura , Feminino , Hipotálamo/análise , Hipotálamo/ultraestrutura , Ensaio Radioligante , Ratos , Ratos Endogâmicos , Receptores Adrenérgicos beta/análise , Receptores Adrenérgicos beta/ultraestrutura , Fatores de Tempo
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