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41.
Tim H.-M. Huang Diane Peckham Jacqueline R. Batanian Matthew B. Martin Melissa Kouba Charles W. Caldwell Judith H. Miles 《Clinical genetics》1994,46(4):299-303
We describe two brothers and a cousin with common clinical features, including mild mental retardation, motor delays, hypotonia with truncal ataxia, esotropia, and mild facial and hand dysmorphia. The initial routine chromosome study failed to detect any abnormality in the proband. Based on a high index of clinical suspicion, high-resolution chromosome studies were performed on the proband's parents. A small reciprocal translocation t(10;14) (q26.1;q32.3) was detected in the father. The breakpoint on the derivative chromosome 14 was further placed telomeric to the immunoglobulin heavy-chain gene cluster at the band q32.33 by fluorescence in situ hybridization. Studies of the proband and two affected paternal cousins revealed that each had inherited the same derivative chromosome 10 from their carrier parents. This unbalanced karyotype resulted from an adjacent-1 segregation of the 10;14 translocation. 相似文献
42.
Local active gingival immunization by a 3,800-molecular-weight streptococcal antigen in protection against dental caries. 总被引:1,自引:3,他引:1
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Local gingival immunization was attempted in an effort to confine the immune response to the oral cavity and bypass the systemic immune response. A low-molecular-weight (3.8K) streptococcal antigen (SA) I/II was applied 10 times over a period of 1 year to the gingival crevices of rhesus monkeys. The antigen was maintained in situ by means of silicone rubber appliances. Serial examinations over a period of 1 year showed that topical gingival immunization with the 3.8K SA results in a significantly lower incidence of dental caries and colonization of Streptococcus mutans compared with that of the sham-immunized controls. This was associated with an increase in gingival crevicular immunoglobulin G and salivary immunoglobulin A anti-SA I/II antibodies, whereas no change occurred in serum antibodies to SA I/II. The immune mechanism which prevents the colonization of S. mutans and the development of caries may involve antibodies that prevent the adherence of S. mutans to the teeth and facilitate phagocytosis and killing by the local neutrophils. This novel route of local immunization is noninvasive, does not cause side effects, and bypasses systemic immunization. 相似文献
43.
44.
Clearance of Chlamydia trachomatis from the murine genital mucosa does not require perforin-mediated cytolysis or Fas-mediated apoptosis 总被引:3,自引:0,他引:3
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The molecular mechanisms of resistance to genital infection with the mouse pneumonitis (MoPn) strain of Chlamydia trachomatis are unknown. A role for major histocompatibility complex class II-restricted, interleukin-12-dependent CD4(+) T cells has been established, but the functional activity of these cells does not depend on secretion of gamma interferon. Here we examined the potential contribution of T-cell-mediated cytotoxicity and apoptosis to mucosal clearance of MoPn by using mice deficient in the molecular mediators of target cell lysis. Animals lacking perforin, Fas, Fas ligand, or both perforin and Fas ligand were infected genitally with C. trachomatis MoPn and monitored for expression of immunity to chlamydial antigens and clearance of MoPn from the genital mucosa. In each case, the profile of spleen cytokine production, the magnitude of the host antibody response, and the kinetics of chlamydial clearance were similar to those of genetically intact controls. Compensatory overproduction of tumor necrosis factor alpha, an alternate mediator of apoptosis in certain cell types, did not appear to account for the ability of mutant mice to resolve Chlamydia infections. These results fail to support CD4(+) T-cell-mediated apoptosis or CD8(+) T-cell-mediated cytotoxicity as being critical to the clearance of C. trachomatis MoPn urogenital infections. 相似文献
45.
Polymorphisms in the Chlamydia trachomatis cytotoxin locus associated with ocular and genital isolates
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Carlson JH Hughes S Hogan D Cieplak G Sturdevant DE McClarty G Caldwell HD Belland RJ 《Infection and immunity》2004,72(12):7063-7072
Chlamydia trachomatis is a strict human pathogen producing infections that cause medically important chronic inflammatory diseases, such as blinding trachoma and tubal factor infertility. Isolates exist as serotypes that fall into distinct biologic and pathological groups corresponding to differences in infection tissue tropism and invasion properties. Paradoxically, genome sequencing of several diverse strains has revealed a remarkable level of genomic synteny, suggesting that minor genetic differences determine the pathogen host- and tissue-specific infection characteristics. To better understand the genetic basis of chlamydial pathobiologic diversity, we performed comparative DNA-DNA microarray genomic hybridizations with all 15 C. trachomatis serovariants. We found there are few major genetic differences among the 15 serovars. An exception was the cytotoxin locus located in the plasticity zone, a region that exhibited significant polymorphisms among serovars. We therefore sequenced this region from all 15 serovars. The cytotoxin gene was interrupted by extensive mutations and deletions among the different serovars; however, three basic open reading frame motifs were discovered that correlated with noninvasive oculotropic, urogenitotropic, and invasive serovars. Of interest, only noninvasive genitotropic serovars possessed an intact N-terminal portion of the putative toxin gene. This region contains the UDP-glucose binding domain and the glycosyltransferase domain required for enzymatic activity of the clostridial toxin homologs, suggesting a role in urogenital infection or pathogenesis. 相似文献
46.
C R Yonker K D Caldwell J C Giddings J L Van Etten 《Journal of virological methods》1985,11(2):145-160
A virus (PBCV) from the symbiotic Chlorella-like algae of Paramecium bursaria has been characterized by sedimentation field flow fractionation (SdFFF). The method yields effective molecular weight M' (molecular weight X buoyancy factor) with a precision of better than 5% under a variety of experimental conditions. The value for M' is used to calculate true molecular weight values through combination with density values; densities were obtained from outside sources, from ultrasonic densitometry, and from sedimentation coefficients determined independently. The actual molecular weight is also determined through SdFFF analysis of the virus in carriers of different densities. Values for the particle diameter are obtained from SdFFF zone broadening studies. The various SdFFF characterization results are compared with molecular weight, particle size, and density values determined by conventional methods. 相似文献
47.
Fibrinogen adsorption by PS latex particles coated with various amounts of a PEO/PPO/PEO triblock copolymer 总被引:1,自引:0,他引:1
Bohner M Ring TA Rapoport N Caldwell KD 《Journal of biomaterials science. Polymer edition》2002,13(6):733-746
Polystyrene (PS) latex particles of different sizes were adsorption coated with the polymeric surfactant Pluronic F108 (PEO129-PPO56-PEO129). The commercial surfactant was found to have a bimodal molecular weight distribution. However, the maximum surface concentrations resulting from adsorption of either the purified high molecular weight component or the composite were identical. An increase in the copolymer surface concentration on 252-nm particles was found to decrease their fibrinogen uptake exponentially. At maximum copolymer surface concentration, the fibrinogen uptake was two orders of magnitude lower than that of bare particles (down from 3.3 mg/m2 to 0.03 mg/m2). This surface protection was equally effective whether the adsorption involved the bimodal polymer surfactant or the purified high molecular weight fraction. The PEO tail mobility was investigated with electron paramagnetic resonance (EPR), and found to increase with an increase in polymer surface concentration. The comparatively slow motion of the PEO chains at low surface concentration indicated that not only the PPO block, but also the PEO blocks interacted hydrophobically with the PS surface. When the copolymer surface concentration was increased, the PEO tails were gradually being released, acquiring higher mobility as the surface became covered by the more strongly binding PPO blocks. Results obtained with F108 coated particles of different sizes showed that particle size had a significant effect on the fibrinogen uptake, with larger particles showing larger fibrinogen uptakes. 相似文献
48.
Oral immunization with Streptococcus mutants in rhesus monkeys and the development of immune response and dental caries. 总被引:3,自引:0,他引:3
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The oral route of immunization with Streptococcus mutants was compared with the subcutaneous route in rhesus monkeys. Significant levels of serum IgG, IgM and IgA antibodies in Strep. mutans were elicited only in monkeys immunized subcutaneously. Similarly, the skin delayed hypersensitivity reaction to Strep. mutans was elicited only in the subcutaneously immunized monkeys. Oral immunization induced a modest increase in salivary IgA antibodies to Strep. mutans, though a slight increase in IgA antibodies was also found in the saliva of all other groups of immunized and control monkeys. A small though not significant reduction in dental caries was found in the monkeys immunized orally, whereas subcutaneous immunization with Strep. mutans consistently elicited a significant reduction in caries. Oral feeding of Strep. mutans failed to induce tolerance to a subsequent subcutaneous challenge by the same organism. Furthermore, sequential subcutaneous followed by oral immunization had little effect on the titre of salivary or serum antibodies. 相似文献
49.
R. N. Scott R. H. Brittain R. R. Caldwell A. B. Cameron V. A. Dunfield 《Medical & biological engineering & computing》1980,18(1):65-69
Progress in the development of a system to provide sensory feedback of the pinch force of an artificial hand is described.
Design criteria relating to electrocutaneous stimulation and compatibility with myoelectric control are discussed. Details
of a practical system, presently in use by two amputees prior to full-scale clinical evaluation, are presented. 相似文献
50.
Economic and social forces have converged to influence the fundamental nature of marriage in the 1980s. Marriages are shifting from the complementary type, in which the husband is employed and the wife cares for the household and children, to the parallel type, in which both spouses are employed and both are responsible for the housework. This study examines the relationship between marital sex role incongruence and marital adjustment. Both the magnitude and the direction of the incongruence are related to marital adjustment level. The study's major hypothesis is that the relationship between marital sex-role incongruence and marital adjustment is a function of both the magnitude of the incongruence and the direction of the disagreement. Couples in the study were recruited from a moderately sized midwestern university community. 103 couples agreed to participate but 73 couples actually returned the questionnaire. Of these 73 couples, 63% were randomly recruited through door-to-door solicitation, 29% were recruited from an evangelical Christian organization and church, and 8% were recruited from acquaintances of the 1st author. After deleting incomplete questionnaires, final sample size was 67 couples. Each member of a marital dyad completed a questionnaire including a Dyadic Adjustment Scale to measure marital adjustment, a Sex-Role Egalitarianism Scale to measure marital sex-role orientation, a Marlowe-Crowne Social Desirability Scale Short Form C to measure social desirability bias, and a demographic information sheet. Findings indicate that direction of incongruence plays a very important role in determining the impact of marital sex-role incongruence on marital adjustment; namely, the greater the incongruence is in the direction of the wife being more egalitarian relative to her husband, the more negative is the estimated impact on marital adjustment. Conversely, the greater the incongruence is in the direction of the husband being more egalitarian than his wife, the more positive is its estimated impact on marital adjustment. 相似文献