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91.
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.  相似文献   
92.
Based on cytogenetic observations, several syndromes have been previously identified as microdeletion-based disorders. In this review, recent progress is presented regarding whether one or multiple genes can be implicated in the pathogenesis of these segmentally aneusomic syndromes. The syndromes discussed include Angelman, Alagille, Williams, Langer-Giedeon, Prader-Willi, Smith-Magenis, Miller-Dieker, and DiGeorge/velocardiofacial or the 22q11 deletion syndromes. For Angelman and Alagille syndromes, single genes have been identified, whereas for Williams and Langer-Giedion syndromes, more than one gene can be implicated. Although there has been significant progress in dissecting the molecular basis for the other disorders, the ultimate answer regarding one versus several genes remains to be determined.   相似文献   
93.
Background: Chronotherapy studies with inhaled corticosteroids have shown optimal therapeutic benefit when steroids are administered four times per day (QID) or once daily at 3 PM.Objective: This study evaluated whether more convenient once-daily dosage times (8 AM and 5:30 PM) produce improvement in asthma equivalent to QID.Methods: Efficacy outcome measures included FEV1, peak expiratory flow rates, bronchial responsiveness, use of β2-agonists, nocturnal awakenings, and responses to a quality of life questionnaire. Systemic effects were blood eosinophil count, cortisol level, 24-hour urinary cortisol, and evaluation for oral candidiasis and dysphonia.Results: Baseline measurements for all three treatment groups were similar. For morning peak expiratory flow rate, significant improvement was seen for the QID group (p = 0.001) and the 5:30 PM group (p = 0.003), but not the 8 AM group (p = 0.75). For evening peak expiratory flow rate, significant improvement was seen for the QID group (p = 0.005) and the 5:30 PM group (p = 0.01), but not for the 8 AM group (p = 0.47). There were significant improvements in all other outcome variables for each group except PC20. There was a significant improvement in PC20 only in the QID group. The systemic effects of the three regimens were comparable.Conclusion: Dosing of inhaled steroid at 5:30 PM had no increased systemic effects and produced efficacy similar to QID dosing. Dosing at 8 AM did not produce results consistently comparable to QID dosing. Optimal once-daily dosing of inhaled steroid is between 3 PM and 5:30 PM.  相似文献   
94.
We describe an infant girl, born with a pigmented giant nevus, who developed a malignant schwannoma in the retroperitoneum at 16 months of age. At birth the nevus covered over 50% of her body and histologically was a compound nevus with extension into the deep dermis surrounding dermal appendages. The malignant schwannoma was biphasic with areas composed of spindle and round cells. Ultrastructurally, the majority of the tumor cells exhibited a Schwann cell phenotype, but neuroepithelial and melanocytic cells were identified as well. We believe that this constellation of findings represents a form of neurocristopathy. Neurocristopathy, as defined by Bolande (Hum Pathol 5:409–429, 1974), is a disease that results from aberrations in the migration, growth, or cytodifferentiation of neural crest tissues. These diseases may be simple (a singular pathologic process, usually localized) or complex (multiple neuroectodermal lesions). We report this case because the occurrence of retroperitoneal malignant schwannoma arising in a 16-month-old infant born with a pigmented giant nevus is unique, and may represent a previously undescribed form of a complex neurocristopathy.  相似文献   
95.
Background: No published studies have compared the effectiveness of several treatments proposed to reduce cat allergenicity. Cat washing studies demonstrating efficacy involved very small sample sizes or infrequent washings. Allerpet-C (Allerpet, Inc., New York, N.Y.), a widely advertised topical spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating doses, have never been scientifically studied. Objective: We compared the effects of cat washing, Allerpet-C spray, and acepromazine with that of no treatment on the shedding of the primary cat allergen, Felis domesticus I by cats. Methods: In a blinded, comparative, controlled study, we measured the amounts of Fel d I shed during an 8-week treatment period with a sample of 24 female mongrel cats randomly assigned to four groups; one group received weekly distilled water washings, one received weekly Allerpet-C spray applications, one received daily oral acepromazine, and one had no treatment (control). Thirty-minute, twice-weekly air samples were collected from each cat with a laminated plastic–acrylic chamber and air sampler. Results: One-sample, two-sided t tests comparing baseline to final-week measurements revealed no significant change in Fel d I within each group (mean change ±SD: washing; 487.6 ± 1896.4 mU per 30 minutes, p = 0.63; Allerpet-C spray, 429.2 ± 871.6 mU per 30 minutes, p = 0.46 acepromazine; −620.6 ± 1031.2, p = 0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant change in Fel d I levels between groups (p = 0.72). Conclusions: Our data do not show significant reductions in Fel d I shedding as a result of any of these treatments. Therefore we cannot recommend them to patients allergic to cats. (J ALLERGY CLIN IMMUNOL 1995;95:1164-71.)  相似文献   
96.
Polyvinyl chloride (PVC) tubing is an indispensable medical material for extracorporeal circulation therapy. However, di(2-ethylhexyl)phthalate (DEHP), a suspected endocrine disruptor, can be eluted from PVC, suggesting that an alternative material that does not contain DEHP is needed for clinical applications. First, we evaluated the endocrine disrupting risks of the plasticizers contained in PVC tubes by investigating their binding affinities for the human estrogen receptor alpha (ERα). Our results revealed that, while DEHP has some binding affinity for ERα, neither epoxidized soybean oil nor tris(2-ethylhexyl)trimellitate (an alternative to DEHP) has any affinity for ERα. Second, we evaluated the endocrine disrupting risks of a tube made of newly developed plasticizer-free (PF) materials. We confirmed the presence of DEHP and detected several unidentified substances in plasma stored within the PVC tube. This plasma's competitive binding affinity for ERα was significantly higher than that of control plasma (P < 0.01). In contrast, the profile of plasma stored in the PF tube was similar to that of the control, both in terms of high-performance liquid chromatography chromatograms and competitive binding capacity for ERα, suggesting that the PF tube is biocompatible and is useful for reducing the elution of substances capable of binding to ERα. Presented in part at the 42nd Congress of the Japanese Society for Artificial Organs, October 5–7, 2004, Tokyo, Japan  相似文献   
97.
Background: LPS is a common contaminant in the health care environment and in latex examination gloves. Objective: We sought to investigate the role of LPS in enhancing the immune responses of mice to inhaled latex allergen. Methods: As our model allergen, we used a fusion protein containing the potent latex allergen Hev b 5. BALB/c mice were lightly anesthetized and given repeated intranasal doses of saline, LPS, and/or Hev b 5. The doses were given in 2 courses separated by a 6-week period, with the first course consisting of 6 doses and the second consisting of 3 doses. Results: After the first set of immunizations, mice given Hev b 5 alone had no detectable IgG1 or IgE responses to Hev b 5, whereas mice given the antigen along with LPS had significant responses (IgG1, 0.73 U ± 0.05; IgE, 0.88 U ± 0.2). No enhancement of specific IgG2a was observed. A stimulatory effect of LPS on all 3 immunoglobulin types was apparent after the second course. Lymphocytes from mice immunized with LPS and Hev b 5 had increased proliferation to Hev b 5 and its fusion partner. Conclusions: LPS may be an important immunoadjuvant for the development of allergic reactions to latex protein allergens. (J Allergy Clin Immunol 199;102:977-83.)  相似文献   
98.
99.
Impaired antibody responses in the hyperimmunoglobulin E syndrome   总被引:1,自引:0,他引:1  
Patients with the hyper-IgE (HIE) syndrome have recurrent bacterial infections with Staphylococcus aureus and other polysaccharide encapsulated organisms. To determine whether an impairment of the antibody response to polysaccharide antigens contributes to infections in this syndrome, we measured serum antibody to the teichoic acid of S. aureus and to the capsular polysaccharide of Haemophilus influenzae type b. Compared to control subjects who had no history of S. aureus infections (N = 14), sera from patients with HIE (N = 9) lacked the expected elevation of serum antibody to teichoic acid (p greater than 0.05) and had significantly lower levels of this antibody than sera from 14 patients with atopic dermatitis, complicated by recurrent cutaneous S. aureus infections (p less than 0.01). After immunization with the capsular polysaccharide of Haemophilus influenzae type of vaccine, the antibody response of patients with HIE was significantly impaired compared to that of age-matched control subjects (p = 0.01). Although patients with HIE syndrome had normal total IgG levels, most patients with HIE but not patients with atopic dermatitis had IgG2 subclass deficiency. Defective antibody responses in patients with HIE were not restricted to polysaccharide antigens because the serum levels of antitetanus toxoid antibody in these patients were significantly lower than that of control subjects (p less than 0.001). Impaired antigen-specific antibody responses in patients with HIE syndrome may contribute to their increased susceptibility to infection.  相似文献   
100.
We have investigated the role of cAMP and cAMP-dependent protein kinase (cAPK) in neutrophil phagocytosis. Inhibition of cAPK with H-89 reduced complement- and IgG-dependent phagocytosis to 83 and 46%, respectively. Fluorescence intensity measurements of phalloidin-stained actin in neutrophils showed a reduced amount of filamentous actin (F-actin) in pseudopods and around the phagosome in cells treated with H-89 or cAMP-elevating agents (forskolin and rolipram). The amount of phosphotyrosine-containing proteins was also reduced in pseudopods and around the phagosome. Taken together, the data show that cAMP/cAPK regulates F-actin reorganization during receptor-mediated phagocytosis, particularly triggered by IgG-FcR interaction. Our results support the hypothesis that active subcortical reorganization of F-actin is a prerequisite for FcR-mediated phagocytosis, but is less important during CR3-mediated ingestion.  相似文献   
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