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21.
The localization of intraglomerular deposits of fibrin (Fb)/fibrinogen (Fg)-related antigen (FRA) in children with various glomerular diseases was determined by an immunohistopathologic method using an anti-Fg antibody capable of detecting FRA, an anti-D-dimer antibody capable of detecting crosslinked Fb (XLFb) and its derivatives (XLFbDP), and by a method using the effect of monochloroacetic acid (MCA) treatment on kidney sections. In proliferative glomerulonephritis (PGN), XLFbs were detected within the capillaries and extension beyond the mesangium was seen in severe PGN. The FRA within the mesangium of minimal or mild PGN was composed of the non-XLFb substance. The FRA within Bowman's space of most PGN had disappeared after MCA treatment, suggesting a non-XLFb substance. The presence of FRA within electron-dense deposits (EDD) suggested that FRA deposits are associated with immune-complex deposits in the glomeruli.  相似文献   
22.
We report a family with inner ear lateral semicircular canal (LSC) malformation and external and middle ear abnormalities. The family had no history of known syndromes or toxic exposures. Distinct phenotypic manifestations were found in three family members. A young girl exhibited bilateral LSC malformation with a right-sided preauricular tag, a mildly deformed auricle, a stenotic external auditory canal, and a constricted middle ear cavity. She had moderate conductive hearing loss in the right ear but normal hearing in the left ear. Her younger brother exhibited right-sided LSC malformation, microtia, external auditory canal atresia, a malformed middle ear cavity, and abnormal auditory ossicles. He had severe mixed hearing loss in his right ear. Their mother exhibited left-sided LSC malformation without external and middle ear abnormalities, and the hearing was normal in her left ear. None of the three cases had vestibular symptoms, and their results of balance tests were appropriate for the corresponding ages. In contrast, significantly decreased LSC function was revealed by caloric tests in an ear with LSC malformation. Previously, LSC malformation may have been underdiagnosed in patients presenting with external and middle ear abnormalities and their relatives, since this malformation is frequently associated with normal hearing and balance or conductive hearing loss only. To our knowledge, this condition has not been described previously. This condition supports a genetic basis for the combination of LSC malformation and external and middle ear abnormalities and may represent an autosomal dominant condition with variable expressivity.  相似文献   
23.
We report the cloning of the gene encoding the 32-kDa lipoprotein, designated LipL32, the most prominent protein in the leptospiral protein profile. We obtained the N-terminal amino acid sequence of a staphylococcal V8 proteolytic-digest fragment to design an oligonucleotide probe. A Lambda-Zap II library containing EcoRI fragments of Leptospira kirschneri DNA was screened, and a 5.0-kb DNA fragment which contained the entire structural lipL32 gene was identified. Several lines of evidence indicate that LipL32 is lipid modified in a manner similar to that of other procaryotic lipoproteins. The deduced amino acid sequence of LipL32 would encode a 272-amino-acid polypeptide with a 19-amino-acid signal peptide, followed by a lipoprotein signal peptidase cleavage site. LipL32 is intrinsically labeled during incubation of L. kirschneri in media containing [(3)H]palmitate. The linkage of palmitate and the amino-terminal cysteine of LipL32 is acid labile. LipL32 is completely solubilized by Triton X-114 extraction of L. kirschneri; phase separation results in partitioning of LipL32 exclusively into the hydrophobic, detergent phase, indicating that it is a component of the leptospiral outer membrane. CaCl(2) (20 mM) must be present during phase separation for recovery of LipL32. LipL32 is expressed not only during cultivation but also during mammalian infection. Immunohistochemistry demonstrated intense LipL32 reactivity with L. kirschneri infecting proximal tubules of hamster kidneys. LipL32 is also a prominent immunogen during human leptospirosis. The sequence and expression of LipL32 is highly conserved among pathogenic Leptospira species. These findings indicate that LipL32 may be important in the pathogenesis, diagnosis, and prevention of leptospirosis.  相似文献   
24.
Even though cigarette smoking has been shown to suppress immune responses in the lungs, little is known about the effect of cigarette smoke components on respiratory infections. In the present study, the effects of cigarette smoke condensate (CSC) on bacterial replication in alveolar macrophages and the immune responses of macrophages to infection were examined. Furthermore, a possible immunotherapeutic effect of epigallocatechin gallate (EGCg), a major form of tea catechins, on the CSC-induced suppression of antimicrobial activity and immune responses of alveolar macrophages was also determined. The treatment of murine alveolar macrophage cell line (MH-S) cells with CSC significantly enhanced the replication of Legionella pneumophila in macrophages and selectively down-regulated the production of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) induced by bacterial infection. The treatment of macrophages with EGCg not only overcame the CSC-induced suppression of antimicrobial activity but also strengthened the resistance of macrophages to infection. EGCg also markedly up-regulated the CSC-suppressed IL-6 and TNF-α production by macrophages in response to infection. The results of exogenous TNF-α treatment and neutralization treatment with anti-TNF-α and anti-gamma-interferon (IFN-γ) antibodies and the determination of IFN-γ mRNA levels indicate that CSC-suppressed macrophages can be activated by EGCg to inhibit L. pneumophila growth by up-regulation of TNF-α and IFN-γ production. Thus, this study revealed that CSC selectively alters the immune responses of macrophages to L. pneumophila infection and leads to an enhancement of bacterial replication in macrophages. In addition, the tea catechin EGCg can diminish such suppressive effects of CSC on alveolar macrophages.  相似文献   
25.
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine carcinomas. Received: 14 April 1999 / Accepted: 7 July 1999  相似文献   
26.
27.
BACKGROUND: Intestinal microbiota are known to play an important role in the establishment of oral tolerance, thereby protecting the organism from food allergies. Dietary intake of nucleic acid (NA) is also reported to have such an anti-allergic effect; however, one unsolved question is whether or not dietary NA would act through a process of toll-like receptor 9 signaling activated by DNA containing a CpG motif, a well-known sequence leading to immunostimulatory activity. In this study, we focused on the question of whether the addition of dietary NA lacking CpG motifs would allow continued modulation of the Th1/Th2 balance. METHODS: Germ free (GF) and Bifidobacterium-infantis-monoassociated BALB/c mice were maintained on either an NA-free casein diet or on an NA-supplemented casein diet for 4 weeks. Thereafter, both the in vivo anti-casein antibody levels and in vitro splenocyte cytokine secretion pattern were evaluated. RESULTS: Feeding with a casein diet elicited a substantial increase in the serum anti-casein-specific IgG1, IgG2a, and IgE levels of GF mice fed the NA free-diet. The in vitro cytokine production profile showed that enhanced IL-4 production in the GF mice fed the NA free-diet was markedly reduced by the supplementation with dietary NA in both the GF and B.-infantis-monoassociated mice. In addition, IFN-gamma secretion increased in the B.-infantis-reconstituted mice fed the diet containing NA. CONCLUSIONS: These results suggest that dietary intake of NA devoid of CpG motifs may prevent the development of allergies via acceleration of Th1-dominant immunity.  相似文献   
28.
Summary In order to clarify the histogenesis of clear cell sarcoma of tendons and aponeuroses (CCS), two cases of human and one nude mouse-transplanted CCS line were studied using an ultrastructural and enzyme cytochemical approach. Most of the tumour cells obtained from the primary and transplanted CCS demonstrated melanosomes in various stages of development within the cytoplasm, whereas no melanosomes could be identified in the metastatic CCS. However, cholinesterase and tyrosinase activities could be demonstrated not only in the melanotic primary and transplanted CCS but also in the amelanotic metastatic CCS. The results therefore support the hypothesis that CCS is a soft tissue tumour derived from the neural crest.  相似文献   
29.
Among Japanese, ossification of the posterior longitudinal ligament of the spine (OPLL) is a leading cause of myelopathy, showing ectopic bone formation in the paravertebral ligament. We have provided genetic evidence that the collagen α2 (XI) (COL11A2) locus of chromosome 6 constitutes susceptibility for OPLL. Five distinct single nucleotide polymorphisms (SNPs), identified in COL11A2, were combined to construct possible haplotypes by the use of a maximum likelihood program. Estimated haplotype frequency was compared in OPLL patients and non-OPLL controls. We report a gender-specific association of the COL11A2 haplotype with OPLL. The frequency of the most commonly observed haplotype was significantly higher in male patients (P = 0.0003) compared with controls, but not in female patients (P = 0.21). OPLL is predominantly observed in males, with a prevalence ratio of 2 : 1, and our gender-specific associations indicate that genetic factors involving COL11A2 play a specific role in the etiology of OPLL exclusively in males. Received: September 5, 2000 / Accepted: October 2, 2000  相似文献   
30.
The proliferative T cell responses to poly(GluLysTyr) (GLT) and poly(GLULysPhe) (GLPhe) are restricted by the E alpha E beta class II MHC molecule (E) in most responded strains. Some nonresponder strains that carry responder E beta, but cannot express cell surface E molecules, can complement with other nonresponder strains that provide the missing E alpha chain needed for the expression of E molecules and for responsiveness to GLT and GLPhe. Here another type of complementation is described between two E-nonexpressor haplotypes, H-2f and H-2s, which result in E-nonexpressor F1 hybrids, which are responders to GLT. The restriction element involved in this response is an Af/As hybrid molecule. The data support the hypothesis that conformational determinants resulting from the free association of alpha and beta chains in heterozygotes can increase the immune potential of the individual.  相似文献   
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