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BACKGROUND AND PURPOSE: Choroidal anastomosis, a hemorrhage-prone periventricular collateral manifestation in Moyamoya disease, outflows to the cortex posterior to the central sulcus. The objective of the present study was to test whether the angiographic extent of revascularization posterior to the central sulcus contributes to the postoperative reduction of choroidal anastomosis. MATERIALS AND METHODS: This retrospective cohort study included choroidal anastomosis-positive hemispheres before direct bypass surgery. The postoperative reduction of choroidal anastomosis was determined by a consensus of 2 raters according to the previous research. An imaging software automatically traced the angiographic revascularization area, which was subsequently divided into anterior and posterior parts by an anatomic line corresponding to the central sulcus. Each area was quantitatively measured as a percentage relative to the whole supratentorial area. RESULTS: Postoperative reduction of choroidal anastomosis was achieved in 68 (85.0%) of the 80 included hemispheres. The revascularization area posterior to the central sulcus was significantly larger in the hemispheres with reduction than in those with no reduction (mean, 15.2% [SD, 7.1%] versus 4.2% [SD, 3.4%], P < .001), whereas no significant difference was observed in the revascularization area anterior to the central sulcus. Multivariate analysis revealed that the revascularization area posterior to the central sulcus was the only significant factor associated with reduction (OR, 1.57; 95% CI, 1.21-2.03, for every 1% increase). CONCLUSIONS: The results suggest that a larger revascularization posterior to the central sulcus is associated with postoperative reduction of choroidal anastomosis regardless of the extent of anterior revascularization. It might facilitate optimal selection of the revascularization site for preventing hemorrhage.
Assuntos
Revascularização Cerebral , Doença de Moyamoya , Humanos , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Doença de Moyamoya/complicações , Estudos Retrospectivos , Angiografia Cerebral , Anastomose Cirúrgica/métodos , Revascularização Cerebral/métodosRESUMO
We report on laser-excited angle-resolved photoemission spectroscopy in the electron-doped cuprate Sm1.85Ce0.15CuO(4-δ). The data show the existence of a nodal hole-pocket Fermi surface both in the normal and superconducting states. We prove that its origin is long-range antiferromagnetism by an analysis of the coherence factors in the main and folded bands. This coexistence of long-range antiferrmagnetism and superconductivity implies that electron-doped cuprates are two-Fermi-surface superconductors. The measured superconducting gap in the nodal hole pocket is compatible with a d-wave symmetry.
RESUMO
Circular dichroism in the angular distribution of photoelectrons from SrTiO(3):Nb and Cu(x)Bi(2)Se(3) is investigated by 7-eV laser angle-resolved photoemission spectroscopy. In addition to the well-known node that occurs in the circular dichroism pattern when the incidence plane matches the mirror plane of the crystal, we show that another type of node occurs when the mirror plane of the crystal is vertical to the incidence plane and the electronic state is two-dimensional. The flower-shaped circular dichroism patterns in the angular distribution occurring around the Fermi level of SrTiO(3):Nb and around the Dirac point of Cu(x)Bi(2)Se(3) are explained on equal footings. We point out that the penetration depth of the topological states of Cu(x)Bi(2)Se(3) depends on momentum.
RESUMO
Electronic structures of the quantum critical superconductor ß-YbAlB4 and its polymorph α-YbAlB4 are investigated by using bulk-sensitive hard x-ray photoemission spectroscopy. From the Yb 3d core level spectra, the values of the Yb valence are estimated to be â¼2.73 and â¼2.75 for α- and ß-YbAlB4, respectively, thus providing clear evidence for valence fluctuations. The valence band spectra of these compounds also show Yb2+ peaks at the Fermi level. These observations establish an unambiguous case of a strong mixed valence at quantum criticality for the first time among heavy fermion systems, calling for a novel scheme for a quantum critical model beyond the conventional Doniach picture in ß-YbAlB4.
RESUMO
Laser angle-resolved photoemission spectroscopy (ARPES) is employed to investigate the temperature (T) dependence of the electronic structure in BaFe2As2 across the magnetostructural transition at T{N} approximately 140 K. A drastic transformation in Fermi surface (FS) shape across T{N} is observed, as expected by first-principles band calculations. Polarization-dependent ARPES and band calculations consistently indicate that the observed FSs at k{z} approximately pi in the low-T antiferromagnetic state are dominated by the Fe3d{zx} orbital, leading to the twofold electronic structure. These results indicate that magnetostructural transition in BaFe2As2 accompanies orbital-dependent modifications in the electronic structure.
RESUMO
BACKGROUND AND PURPOSE: Collateral vessels in Moyamoya disease represent potential sources of bleeding. To test whether these cortical distributions vary among subtypes, we investigated cortical terminations using both standardized MR imaging and MRA. MATERIALS AND METHODS: Patients with Moyamoya disease who underwent MR imaging with MRA in our institution were enrolled in this study. MRA was spatially normalized to the Montreal Neurological Institute space; then, collateral vessels were measured on MRA and classified into 3 types of anastomosis according to the parent artery: lenticulostriate, thalamic, and choroidal. We also obtained the coordinates of collateral vessel outflow to the cortex. Differences in cortical terminations were compared among the 3 types of anastomosis. RESULTS: We investigated 219 patients with Moyamoya disease, and a total of 190 collateral vessels (lenticulostriate anastomosis, n = 72; thalamic anastomosis, n = 21; choroidal anastomosis, n = 97) in 46 patients met the inclusion criteria. We classified the distribution patterns of collateral anastomosis as follows: lenticulostriate collaterals outflowing anteriorly (P < .001; 95% CI, 67.0-87.0) and medially (P < .001; 95% CI, 11.0-24.0) more frequently than choroidal collaterals; lenticulostriate collaterals outflowing anteriorly more frequently than thalamic collaterals (P < .001; 95% CI, 34.0-68.0); and choroidal collaterals outflowing posteriorly more frequently than thalamic collaterals (P < .001; 95% CI, 14.0-34.0). Lenticulostriate anastomoses outflowed to the superior or inferior frontal sulcus and interhemispheric fissure. Thalamic anastomoses outflowed to the insular cortex and cortex around the central sulcus. Choroidal anastomoses outflowed to the cortex posterior to the central sulcus and the insular cortex. CONCLUSIONS: Cortical distribution patterns appear to differ markedly among the 3 types of collaterals.
Assuntos
Córtex Cerebral/irrigação sanguínea , Circulação Colateral , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/patologia , Adulto , Angiografia Cerebral/métodos , Córtex Cerebral/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Japão , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodosRESUMO
OBJECTIVE: To compare the effectiveness of polyvinylidene (PVL) food wrap as a dressing material versus conventional ointments and gauze dressings for pressure ulcers in patients aged 60 years or over. METHODS: A prospective open controlled trial was conducted. The severity of pressure ulcers in both groups was evaluated using the DESIGN system. Scores were compared at baseline, four, eight and 12 weeks. RESULTS: Twenty-five patients were treated with the PVL film (test) dressings and 24 with the conventional treatment (control). The test group showed greater improvement in DESIGN scores than the control group throughout the observation period, and the difference reached statistical significance at 12 weeks (p < 0.05). The incidences of local wound infection in the two groups were not statistically different (p > 0.999). CONCLUSION: The PVL film dressing was more effective than conventional treatment in the management of severe pressure ulcers.
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Curativos Oclusivos/normas , Polivinil/uso terapêutico , Úlcera por Pressão/enfermagem , Higiene da Pele/instrumentação , Idoso , Idoso de 80 Anos ou mais , Pesquisa em Enfermagem Clínica , Feminino , Geriatria , Hospitais Especializados , Humanos , Incidência , Japão/epidemiologia , Masculino , Avaliação em Enfermagem , Curativos Oclusivos/efeitos adversos , Polivinil/efeitos adversos , Úlcera por Pressão/diagnóstico , Estudos Prospectivos , Segurança , Índice de Gravidade de Doença , Higiene da Pele/efeitos adversos , Higiene da Pele/métodos , Higiene da Pele/enfermagem , Resultado do Tratamento , Cicatrização , Infecção dos Ferimentos/epidemiologia , Infecção dos Ferimentos/etiologiaRESUMO
To clarify the neural correlates and brain activity during the progression of human non-rapid eye movement (NREM) sleep, we examined the absolute regional cerebral blood flow (rCBF) during light and deep NREM sleep and during wakefulness in normal humans using positron emission tomography with H(2)(15)O. Relative changes in rCBF during light and deep NREM sleep in comparison to the rCBF during wakefulness were also analyzed. During light NREM sleep, the rCBF in the midbrain, in contrast to that in the pons and thalamic nuclei, did not decrease when compared to that during wakefulness, whereas rCBF decreased in the left medial frontal gyrus, left inferior frontal gyrus, and left inferior parietal gyrus of the neocortex. During deep NREM sleep, the rCBF in the midbrain tegmentum decreased, and there was a marked and bilateral decrease in the rCBF in all neocortical regions except for the perirolandic areas and the occipital lobe. There have been three groups of brain structures, each representing one type of deactivation during the progression of NREM sleep. The activity of the midbrain reticular formation is maintained during light NREM sleep and therefore represents a key distinguishing characteristic between light and deep NREM sleep. Selective deactivation of heteromodal association cortices, including those related to language, occurs with increasingly deep NREM sleep, which supports the recent theory that sleep is not a global, but it is a local process of the brain.
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Mapeamento Encefálico , Encéfalo/fisiologia , Circulação Cerebrovascular/fisiologia , Mesencéfalo/fisiologia , Neocórtex/fisiologia , Formação Reticular/fisiologia , Fases do Sono/fisiologia , Adulto , Cerebelo/fisiologia , Humanos , Masculino , Mesencéfalo/irrigação sanguínea , Neocórtex/irrigação sanguínea , Fluxo Sanguíneo Regional , Formação Reticular/irrigação sanguínea , Vigília/fisiologiaRESUMO
The aim of this study was to compare circadian and sleep characteristics between patients with delayed sleep phase syndrome (DSPS) and healthy controls. The authors studied 8 DSPS patients and 15 normal controls. Serum melatonin concentration was assessed every hour for 24 h under dim light conditions. The sleep phase and the melatonin rhythm in DSPS patients were significantly delayed compared to those in normal controls. Sleep length was significantly greater in DSPS patients compared to that in controls, but the duration of melatonin secretion did not differ between the two groups. The final awakening, relative to melatonin onset, melatonin midpoint, and melatonin offset, was significantly longer in DSPS patients than in controls. By contrast, the timing of sleep onset relative to melatonin rhythm did not differ between the two groups. The authors found a significant positive correlation between sleep phase markers and melatonin phase markers in DSPS. They postulate that a delayed circadian pacemaker may be responsible for delayed sleep phase syndrome. The alteration of phase angle between melatonin rhythm and sleep phase suggested that not only the delay of the circadian clock but also a functional disturbance of the sleep-wake mechanism underlies DSPS.
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Ritmo Circadiano , Melatonina/sangue , Transtornos do Sono-Vigília/fisiopatologia , Adolescente , Adulto , Temperatura Corporal , Feminino , Hábitos , Humanos , Masculino , Sono , Distúrbios do Início e da Manutenção do Sono/sangue , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Transtornos do Sono-Vigília/sangue , Fatores de TempoRESUMO
Recent studies suggest that an exemplary Kondo insulator SmB6 belongs to a new class of topological insulators (TIs), in which non-trivial spin-polarized metallic states emerge on surface upon the formation of Kondo hybridization gap in the bulk. Remarkably, the bulk resistivity reaches more than 20 Ω cm at 4â K, making SmB6 a candidate for a so-called bulk-insulating TI. We here investigate optical-pulse responses of SmB6 by pump-and-probe photoemission spectroscopy. Surface photovoltage effect is observed below ~90â K. This indicates that an optically-active band bending region develops beneath the novel metallic surface upon the bulk-gap evolution. The photovoltaic effect persists for >200â µs, which is long enough to be detected by electronics devices, and could be utilized for optical gating of the novel metallic surface.
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The biological activity of 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3], 23(S)25(R)-1 alpha,25(OH)2D3-26,23-lactone, and three intermediate metabolites of the lactone in vivo and in vitro was comparatively examined. The three intermediate metabolites, 1 alpha,25(R)26(OH)3D3, 1 alpha,23(S)25(R)26(OH)4D3, and 23(S)25(R)-1 alpha,25(OH)2D3-26,23-lactol, stimulated increases, as did 1 alpha,25(OH)2D3, in intestinal calcium transport and serum calcium level in vitamin D-deficient rats fed a low-calcium diet. On the other hand, 23(S)25(R)-1 alpha,25(OH)2D3-26,23-lactone increased the calcium transport but decreased the serum calcium level. 1 alpha,25(OH)2D3,23(S)25(R)-Lactone and the other three metabolites stimulated multinucleate cell formation from hematopoietic blast cells in a manner correlated with their binding affinities for the 1 alpha,25(OH)2D3 receptor. But 23(S)25(R)-lactone did not show any inhibitory effect on the multinucleate cell formation induced by 1 alpha,25(OH)2D3 in contrast to the results obtained from unfractionated marrow cultures. Conditioned medium obtained from 23(S)25(R)-lactone-treated MC3T3-E1 cells inhibited the formation, probably by the action of some inhibitory factors elaborated by the cells treated with the lactone, whereas conditioned medium obtained from 1 alpha,25(OH)2D3 or other metabolite-treated MC3T3-E1 cells stimulated the formation. These findings suggest that 23(S)25(R)-1 alpha,25(OH)2D3-26,23-lactone might inhibit bone resorption through an inhibition of osteoclastic cell formation and that other vitamin D3 metabolites stimulate bone resorption by development of new osteoclastic cells in addition to indirect osteoclast activation.
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Osso e Ossos/metabolismo , Calcitriol/análogos & derivados , Calcitriol/farmacologia , Cálcio/metabolismo , Duodeno/metabolismo , Animais , Biotransformação , Osso e Ossos/efeitos dos fármacos , Calcitriol/metabolismo , Células Cultivadas , Duodeno/efeitos dos fármacos , Absorção Intestinal/efeitos dos fármacos , Cinética , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Ratos , Ratos Endogâmicos , Valores de Referência , Relação Estrutura-Atividade , Deficiência de Vitamina D/metabolismoRESUMO
Using our new culture system for multinucleate cells (MNCs) that have many characteristics of osteoclasts, we examined the effects of factors produced by osteoblastic cells on osteoclastic cell formation. Conditioned medium (CM) from undifferentiated osteoblastic MC3T3-E1 cells during their growth phase inhibited MNC formation in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Diluted CM (1:81) from differentiated cells obtained after cultivation for more than 20 days stimulated MNC formation, but at lower dilutions inhibited their formation. Dialyzed CM (greater than 2000 mol wt) from the differentiated cells was more stimulatory than undialyzed CM and showed no inhibitory effect on MNC formation. The inhibitory effect was observed with filtered (less than 3000 mol wt) CMs and was specific for osteoblastic cell CM. Prostaglandin E2 (PGE2) was detected in the CM from undifferentiated or differentiated MC3T3-E1 cells at concentrations (317 +/- 66 and 1287 +/- 179 pg/ml, respectively) sufficient to inhibit MNC formation, and this inhibition was partially abolished with CM (at 3-fold dilution) in indomethacin-treated cells (PGE2, less than 20 pg/ml), suggesting PGE2-mediated inhibition of MNC formation and the presence of another factor(s) besides PGE2 that influenced MNC formation. In contrast to day 3 CM plus 1,25-(OH)2D3, day 60 CM plus 1,25-(OH)2D3 induced MNC formation even in the absence of GM-CSF, and this induction was inhibited by an antibody to GM-CSF. Secondary colony formation assays showed the presence of a GM-CSF-like factor in the day 60 CM. These findings indicate that osteoblastic cells are involved in the process of osteoclastic cell formation, with at least two soluble factors produced by osteoblasts, a GM-CSF-like factor, which is stimulatory, and PGE2, which is inhibitory. The effects of CMs also differed depending on the stage of osteoblast differentiation.
Assuntos
Osteoblastos/fisiologia , Osteoclastos/citologia , Animais , Calcitriol/farmacologia , Diferenciação Celular , Divisão Celular , Linhagem Celular , Células Cultivadas , Meios de Cultura , Técnicas Citológicas , Dinoprostona/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Camundongos , Osteoblastos/citologia , Osteoblastos/metabolismoRESUMO
The pineal hormone melatonin has some circadian regulatory effects and is assumed to have a close relation with sleep initiation and maintenance. Many previous reports have described age-related decreases in melatonin levels, especially in elderly insomniacs (EIs), which may act as causal or exacerbating factors in sleep disturbances in the elderly. Ten elderly residents with psychophysiological insomnia (mean age, 74.2 yr), 10 healthy residents of the same home [elderly control (EC) group; mean age, 72.7 yr], and 10 healthy young control subjects (mean age, 20.9 yr) living at home participated in this study. The elderly persons, especially the EIs, were exposed to significantly less environmental light and simultaneously suffered from significantly diminished nocturnal melatonin secretion. Supplementary exposure to 4 h (1000 to 1200 h, 1400 to 1600 h) of midday bright light in the EI group significantly increased melatonin secretion to levels similar to those in the young control group without circadian phase-shifting. There was a tendency for the magnitude of the increase in nocturnal melatonin secretion stimulated by bright light to parallel amelioration of sleep disturbances in these subjects. The present findings suggest that we need to pay attention to elderly individuals who suffer under conditions of poor environmental light resulting in disorganized circadian rhythms, including the sleep-wake cycle.
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Envelhecimento/metabolismo , Iluminação , Melatonina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Feminino , Humanos , Masculino , Periodicidade , Valores de Referência , Sono/fisiologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologiaRESUMO
BACKGROUND: There is growing evidence that the dysregulation of circadian rhythms may play an important role in irregular sleep-waking in demented elderly. In this study, we investigated daily variation of the pineal hormone melatonin, which has been reported to possess hypnogenic and synchronizing effects, in patients with senile dementia of Alzheimer's type. METHODS: Serum melatonin secretion rhythms in inpatients with senile dementia of Alzheimer's type (SDAT group, n = 10, average age = 75.7 years) with disturbed sleep-waking and nondemented elderly (ND group, n = 10, age = 78.3 years) without clinical sleep disorders in the same facility were monitored under a dim light condition without excessive physical exercise. RESULTS: The SDAT group showed a significantly higher degree of irregularities in actigraphically recorded rest-activity (R-A) rhythm during the 7-day baseline period compared with the ND group. The SDAT group simultaneously showed significantly reduced amplitude, larger variation of peak times, and diminished amount of total secretion in the melatonin secretion rhythm compared with the ND group. There were significantly positive correlations between the severity of R-A rhythm disorder and the reduced amplitude as well as diminished amount of total melatonin secretion. CONCLUSIONS: The SDAT patients with disturbed sleep-waking possessed melatonin secretion rhythm disorders that may play an important role in irregular sleep-waking in demented elderly.
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Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Ritmo Circadiano/fisiologia , Melatonina/metabolismo , Transtornos do Sono-Vigília/fisiopatologia , Idoso , Análise de Variância , Estudos de Casos e Controles , Fatores de Confusão Epidemiológicos , Ambiente Controlado , Exercício Físico/fisiologia , Humanos , Monitorização Fisiológica , Atividade Motora/fisiologia , Estimulação LuminosaRESUMO
BACKGROUND: The fact that most women experience sleep changes across the menstrual cycle is thought to be associated with changes in circadian rhythms; however, few studies have investigated this relationship. METHODS: We applied an ultrashort sleep-wake schedule to eight healthy women and studied diurnal fluctuations in sleep propensity, sleepiness, rectal temperature, and serum concentrations of melatonin, thyroid-stimulating hormone, and cortisol in the follicular and luteal phases. RESULTS: In the luteal phase, amplitude of core body temperature, total melatonin secretions, and amplitudes of TSH and cortisol rhythms were significantly decreased, whereas sleepiness and occurrence of slow-wave sleep during the daytime were significantly increased. Differences in the amount of daytime slow-wave sleep across the menstrual cycle were positively correlated with differences in the daily mean rectal temperature. CONCLUSIONS: The findings suggest that the amplitude of circadian oscillation may be dampened in the luteal phase. Increased daytime sleepiness in the luteal phase may be associated with increased daytime slow-wave sleep, due possibly to changes in thermoregulation in the luteal phase.
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Ritmo Circadiano , Ciclo Menstrual/fisiologia , Sono/fisiologia , Adulto , Análise de Variância , Temperatura Corporal/fisiologia , Estudos Cross-Over , Estradiol/metabolismo , Feminino , Fase Folicular/fisiologia , Humanos , Hidrocortisona/metabolismo , Fase Luteal/fisiologia , Melatonina/metabolismo , Polissonografia , Progesterona/metabolismo , Tireotropina/metabolismoRESUMO
Using an actigraph and a long-term body temperature (BT) monitoring system, we simultaneously monitored rest-activity (R-A) and BT rhythms in patients with senile dementia of Alzheimer's type (SDAT; n = 20) or multi-infarct dementia (MID; n = 21) for 5-7 consecutive days. The SDAT group exhibited a well-organized BT rhythm with significantly higher amplitude compared with the MID group. The SDAT group also showed significant positive correlation between the total daily activity as well as percentage of nighttime activity and the degree of dementia, while no such tendency was observed in the MID group. The different properties of the biological rhythm disorders among the SDAT and MID groups possibly underlie their sleep and behavioral disorders.
Assuntos
Doença de Alzheimer/fisiopatologia , Ritmo Circadiano/fisiologia , Demência por Múltiplos Infartos/fisiopatologia , Idoso , Temperatura Corporal/fisiologia , Feminino , Humanos , Masculino , Movimento/fisiologia , Sono/fisiologia , Vigília/fisiologia , Punho/fisiologiaRESUMO
We studied an 84-year-old man with a 20-year history of nocturnal violent behavior during sleep, but no other clinically evident neuropsychiatric disorders. Polysomnographic investigations confirmed that he suffered from REM sleep behavior disorder (RBD). Histopathologic examination revealed he had Lewy body disease with a marked decrease of pigmented neurons in the locus ceruleus and substantia nigra. These histologic findings represent the first documented evidence of a loss of brainstem monoaminergic neurons in clinically idiopathic RBD and suggest that Lewy body disease might provide an explanation for idiopathic RBD in the aged.
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Doença de Parkinson/fisiopatologia , Transtornos do Sono-Vigília/fisiopatologia , Sono REM/fisiologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Humanos , Masculino , PolissonografiaRESUMO
A solid-phase radioimmunoassay for quantitating anti-double-stranded deoxyribonucleic acid antibodies (anti-dsDNA) in IgG, IgM and IgA classes has been devised. A distinct feature of the method is an application of polystyrene tubes coated with poly-L-lysine, through which dsDNA could be bound firmly to a solid phase. Studies on patients' sea as well as normal sera revealed that anti-dsDNA was not qualitatively but quantitatively characteristic of systemic lupus erythematosus (SLE) and that IgG anti-dsDNA levels correlated well with the disease activity.
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Anticorpos/análise , DNA/imunologia , Radioimunoensaio/métodos , Anticorpos/metabolismo , Anticorpos Anti-Idiotípicos/metabolismo , Estabilidade de Medicamentos , Humanos , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Cinética , Lúpus Eritematoso Sistêmico/sangue , Filtros Microporos , Poliestirenos , Fator Reumatoide/farmacologiaRESUMO
The binding properties of C1q solid-phase radioimmunoassay (C1q SPRIA) were examined, using heat-aggregated IgG (HAG) as the model of immune complexes (IC). The free, liquid-phase C1q, which was added to the C1q-coated tubes prior to the addition of HAG, had little inhibitory effect on binding of HAG to the solid-phase C1q, suggesting that the solid-phase C1q has a higher affinity for HAG than the liquid-phase C1q. On the other hand, more than 60% inhibition was seen when HAG was preincubated with the liquid-phase C1q. These binding properties of HAG to the solid-phase C1q in the presence of the liquid-phase C1q were not essentially altered by the heat inactivation or the addition of EDTA, suggesting that these pretreatments are not essential in C1q SPRIA. Next, in similar kinds of experiments, the binding properties of C1q-binding IgG complexes in SLE sera were investigated. In contrast to HAG, the binding capacity of IgG complexes in SLE sera to the solid-phase C1q was not inhibited by the preincubation with excess liquid-phase C1q. These findings suggest that C1q-binding IgG complexes in SLE sera detected by C1q SPRIA may not be bound to endogenous C1q in the circulation.
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Complexo Antígeno-Anticorpo , Enzimas Ativadoras do Complemento/imunologia , Imunoglobulina G/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Autoanticorpos/imunologia , Enzimas Ativadoras do Complemento/análise , Complemento C1q , Ácido Edético/farmacologia , Temperatura Alta , Humanos , Radioimunoensaio/métodos , SolubilidadeRESUMO
To assess the immunologic disturbance in WErner syndrome, antibodies to "intrinsic" (auto)antigens (anti-DNA antibodies and rheumatoid factors) and "natural" antibodies to "extrinsic" antigens (hemagglutinins for sheep red cells and antibodies against ABO blood type antigens) were measured in serum samples from 16 patients with Werner syndrome and compared with those from 150 healthy persons ranging in age from less than a year to 98. Employing a sensitive solid-phase radioimmunoassay, we found that the levels of both anti-double-stranded and anti-single-stranded DNA antibodies in the IgG class gradually increased with age in normal donors; a more abrupt increase with age was observed in those with Werner syndrome, although they lacked any complication of renal disease and hypocomplementemia. The titers of rheumatoid factor detected by sensitized sheep cell agglutination also gradually rose in normal persons and patients with Werner syndrome. In contrast, the titers of natural antibodies declined with age in both groups. These disturbances in antibody production suggested that Werner syndrome expresses an accelerated form of aging in immunologic aspect.