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101.
Functional characteristics of an autoreactive (I-Ek-restricted) T cell line (l/+ T1), previously established from MRL/M(p-)+/+(MRL/+) mice with lpr-GVHD, were analyzed in vivo. Intravenous injection of l/+ T1 cells to non-irradiated H-2k (MRL/+ or AKR) mice (but not H-2d mice) induced enhanced spontaneous proliferation of recipient spleen cells; this was also I-Ek self-restricted. This augmented self-reactivity seemed to be mediated by recipient L3T4+ T cells, since few l/+ T1 cells were detected in the spleen cells of l/+ T1-injected AKR mice by cell surface marker analyses, and the treatment of the spleen cells with anti-Thy-1.1 antibody (Ab) or anti-L3T4 Ab plus complement abolished this enhanced spontaneous proliferation. The production of IgM rheumatoid factor (RF) in AKR mice and IgG RF in MRL/+ mice increased, although no enhancement of anti-ssDNA Ab production was observed. Judging from both spleen B cell proportion and serum Ig levels, autoantibody induction by the injection of l/+ T1 cells was not associated with polyclonal B cell activation. When lethally irradiated B10 congenic mice were used as recipients, B10. BR mice showed elevated levels of IgM anti-ssDNA and IgM RF 1 wk after l/+ T1 cell injection; it is likely that lethal irradiation causes autoantigens, particularly DNA, to be exposed. These findings suggest that the autoreactivity of l/+ T1 cells can be transferred to recipient L3T4+ T cells via T-T interaction or the immunological network, and that increased autoreactivity induces autoantibody production in the presence of autoantigen stimulation. In contrast to the stimulatory effects observed in AKR and MRL/+ mice, MRL/Mp-lpr/lpr(MRL/lpr) mice showed a different response to the injection of l/+ T1 cells; spontaneous proliferation of spleen cells and autoantibody production were not enhanced, and suppression of the mitogen responses was observed. It is discussed that lpr-GVHD may be due to these unusual features of MRL/lpr mice.  相似文献   
102.
61 patients suffering from chronic pancreatitis were studied in order to clarify the psychosomatic aspects of this disease. They were classified into 5 types, out of which 3 types were examined in detail according to their personality traits and life habits. It was found that the mind-body relationship took the primary form in the psychosomatic and neurotic types, while in the organic type it took the secondary form such as distorted life habits. This finding indicated that the distortion in the personality structure and that of life habits were closely interrelated. The authors also discussed the clinical features of chronic pancreatitis from the standpoint of alexithymia. The patients with the organic type were most alexithymic, which were followed by the psychosomatic type. It was learned that alexithymic problems were reflected in the patients' life habits.  相似文献   
103.
104.
The reversibility and cation selectivity of the K(+)-Cl(-) cotransporter (KCC), which normally extrudes Cl(-) out of neurons, was investigated in dissociated lateral superior olive neurons of rats using the gramicidin perforated patch technique. Intracellular Cl(-) activity (alpha[Cl(-)](i)) was maintained well below electrochemical equilibrium as determined from the extracellular Cl(-) activity and the holding potential, where the pipette and external solutions contained 150 mM K(+) ([K(+)](pipette)) and 5 mM K(+) ([K(+)](o)), respectively. Extracellular application of 1 mM furosemide or elevated [K(+)](o) increased alpha[Cl(-)](i). When the pipette solution contained 150 mM Cs(+) ([Cs(+)](pipette)), alpha[Cl(-)](i) increased to a value higher than the passive alpha[Cl(-)](i). An increase of alpha[Cl(-)](i) with the [Cs(+)](pipette) was not due to the simple blockade of net KCC by the intracellular Cs(+) since alpha[Cl(-)](i), with the pipette solution containing 75 mM Cs(+) and 75 mM K(+), reached a value between those obtained using the [K(+)](pipette) and the [Cs(+)](pipette). The higher-than-passive alpha[Cl(-)](i) with the [Cs(+)](pipette) was reduced by 1 mM furosemide, but not by 20 microM bumetanide or Na(+)-free external solution, indicating that the accumulation of [Cl(-)](i) in the [Cs(+)](pipette) was mediated by a KCC operating in a reversed mode rather than by Na(+)-dependent, bumetanide-sensitive mechanisms. Replacement of K(+) in the pipette solution with either Li(+) or Na(+) mimicked the effect of Cs(+) on alpha[Cl(-)](i). On the other hand, Rb(+) mimicked K(+) in the pipette solution. These results indicate that K(+) and Rb(+), but not Cs(+), Li(+), or Na(+), can act as substrates of KCC in LSO neurons.  相似文献   
105.
Genomic DNA from 19 Japanese patients with congenital lipoid adrenal hyperplasia (lipoid CAH) representing 16 different families was examined to identify the genetic alterations of steroidogenic acute regulatory protein (StAR). Ten of 19 patients had a 46,XX karyotype and nine had a 46,XY karyotype. Six of the 46,XX patients have experienced spontaneous pubertal changes including breast development and irregular menstruation whereas none of the 46,XY subjects displayed pubertal changes. Eight different mutations were identified. Sixteen patients were either homozygotes or compound heterozygotes for the Q258X mutation. The seven other mutations identified were 189delG, 246insG, 564del13bp, 838delA, Q212X, A218V and M225T. The 189delG, 246insG, 546del13bp and Q212X mutants encode truncated proteins. COS-1 cells transfected with expression vectors encoding cDNAs for the mutant StAR proteins which affect the C-terminus, 838delA, A218V and Q258X, exhibited no steroidogenesis enhancing activity. However, the M225T mutant retained some steroidogenic activity. The patient with the M225T mutation had late onset of this disorder and some capacity to secrete testosterone in response to hCG. These findings suggest: (i) that the Q258X mutation can be used as a genetic marker for the screening of Japanese for lipoid CAH, (ii) that the C-terminus of StAR plays an important role in the protein's activity and (iii) that there are differences in the extent of functional impairment of the testis and ovaries in lipoid CAH.   相似文献   
106.
PSORS1, near HLA-C, is the major genetic determinant of psoriasis. We present genetic and structural evidence suggesting a major role for the HCR gene at the PSORS1 locus. Genotyping of 419 families from six populations revealed that coding single-nucleotide polymorphisms of HCR formed a conserved allele HCR*WWCC that associated highly significantly with psoriasis and with the HLA-Cw6 allele in all populations. Because of strong linkage disequilibrium between HLA-Cw6 and HCR*WWCC, the two genes could not be genetically distinguished by this sample size. However, the variant HCR allele was predicted to differ in secondary structure from the wild-type protein. HCR protein expression in lesional psoriatic skin differed considerably from that observed in normal skin. These results provide strong evidence for the HCR*WWCC allele as a major genetic determinant for psoriasis, probably by a mechanism impacting on keratinocyte proliferation.  相似文献   
107.
The suppressive effect of cleavable penicilloylated dextran (BPO-DEX), whose directly bound penicilloyl groups undergo hydrolytic cleavage within 3 days under physiological conditions, on murine IgE antibody formation against the benzylpenicilloyl (BPO) determinant was investigated in BALB/c and C3H mice. Intraperitoneal administration of BPO-DEX during either primary or secondary IgE responses to BPO ascaris produced a reversible suppression of BPO-specific IgE, while not affecting carrier-specific IgE antibody formation. Suppression of longer duration, at least 10 weeks, was achieved, however, by repeated administrations of BPO-DEX. BPO-DEX itself did not generate detectable BPO-specific IgE antibodies. These results suggest that BPO-DEX might be one of the promising tolerogens in the prevention of penicillin allergy.  相似文献   
108.
BACKGROUND: In Japan in 1993, the Japanese Society of Allergology (JSA) developed guidelines for diagnosis and management of asthma (JGL), which were based on the concept that asthma is a chronic inflammatory disorder of the airway. METHODS: This survey study was intended to investigate the recognition and utilization of JGL among physicians who had treated asthma. The survey comprised two methods: a quantitative mail survey and a qualitative door-to-door survey conducted by trained interviewers. RESULTS: In the mail survey, a total of 1028 physicians responded; 552 members of the JSA and 476 nonmembers. Ninety-four percent of JSA members were aware of adult asthma management guidelines, while 53% of nonmembers were aware of them. Although approximately half of the physicians, both members and nonmembers, found differences between the asthma management policies in JGL and their previous policies, most of them utilized JGL once they read it. In the qualitative door-to-door survey, 80-90% of physicians evaluated JGL as good after they read it. CONCLUSIONS: JGL was recognized and utilized by most JSA members, but only half of nonmember physicians were aware of JGL, although they utilized JGL after they read it. Further action to implement JGL among nonspecialist physicians is needed to improve management of asthma.  相似文献   
109.
In this study, we examined the corrosion behaviors of pure titanium, the alloys Ti-6Al-4V and Ti-6Al-7Nb, and the new experimental alloys Ti-Pt and Ti-Pd using anodic polarization and corrosion potential measurements in an environment containing fluoride. Before and after immersion in the test solutions, we made observations using a scanning electron microscope. The test solutions included an artificial saliva containing 0.2% NaF (corresponding to 905 ppm F) and an artificial saliva with a low concentration of oxygen. Although the surfaces of the Ti-Pt and Ti-Pd alloys were not affected by an acidic environment containing fluoride, the surfaces of the pure titanium, the Ti-6Al-4V alloy, and the Ti-6Al-7Nb alloy were markedly roughened by corrosion. The surfaces of the pure titanium, the Ti-6Al-4V alloy, and the Ti-6Al-7Nb alloy were microscopically damaged by corrosion when they were immersed in the solution containing a low concentration of dissolved oxygen, even with a fluoride concentration included in the commercial dentifrices. In this situation, however, the surfaces of the new Ti-Pt and Ti-Pd alloys were not affected. These alloys are expected to be of use in dental work as new titanium alloys with high corrosion resistances.  相似文献   
110.
The kinetics of IgE-mediated release of serotonin from passively sensitized rat mast cellsin vitro was studied by stopping14C-serotonin release with the application of formaldehyde fixative or ice-cold mast cell medium (MCM). Antigen dose-release curves of14C-serotonin and/or histamine were comparable when mediator release was terminated with either formaldehyde at a final concentration of 1% or ice-cold MCM 15 min after antigen challenge. However, the kinetic study of immunological mediator release stopped by formaldehyde showed that the addition of antigen resulted in a progressive increase of released14C-serotonin for 7 min, the release curve being sigmoidal, whereas the application of ice-cold MCM artificially enhanced14C-serotonin and histamine release in the first 2 min. The results suggest that stopping IgE-mediated release of14C-serotonin with formaldehyde is a simple, rapid and accurate method of studying the kinetics of mediator release from mast cells.  相似文献   
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