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1.
OBJECTIVES: The object of this study was to investigate the diversity among streptococcal species isolated from root canals in conjunction with endodontic therapy and to characterize their production of extracellular proteins. STUDY DESIGN: Consecutive root canal samples (RCS) taken as bacteriological controls during root canal treatment of teeth with apical periodontitis were analyzed in a total of 100 clinical cases. Bacteria were isolated and classified by selective media and gas liquid chromatography. Streptococcal strains were identified by carbohydrate fermentation, hydrolysis of aesculin/arginine, and production of enzymes. Releases of extracellular proteins by streptococci and Enterococcus spp in fluid culture media were examined with SDS-PAGE and 2-dimension gel electrophoresis (2 DE). Extracellular proteins produced were quantified and qualitatively analyzed. Specific proteins were targeted with Western immunoblot assays. Comparisons were made with type strains. RESULTS: Of a total of 241 bacterial strains recovered in the first samples submitted, Streptococcus gordonii, S anginosus, and S oralis were the most frequently isolated streptococci. In 49 of 89 resubmitted samples showing bacterial growth, S gordonii and S oralis still predominated among streptococci. Other common bacterial isolates were Enterococcus spp, Lactobacillus paracasei, and Olsenella uli. Quantitative and qualitative differences in extracellular protein production were observed among clinical isolates and laboratory streptococcal strains. In similar conditions for growth, S intermedius, S anginosus, S oralis, and S gordonii were strong producers of extracellular proteins (>3.0 microg/mL), while Enterococcus spp and S mutans were weak. Whole cell protein extracts showed a different profile from that of extracellular proteins. The chaperone protein DnaK was recognized to be produced extracellularly by S gordonii, S oralis, S anginosus, and S parasanguis. CONCLUSIONS: Being strong producers of extracellular proteins and by virtue of common presence in teeth undergoing endodontic therapy, S gordonii, S anginosus, and S oralis may be of pathogenic significance in posttreatment apical periodontitis.  相似文献   
2.
OBJECTIVE: The Baking Tray Task is a comprehensible, simple-to-perform test for use in assessing unilateral neglect. The aim of this study was to validate further its use with stroke patients. METHODS: The Baking Tray Task was compared with 2 versions of the Behaviour Inattention Test and a test for personal neglect. A total of 270 patients were subjected to a 3-item version of the Behaviour Inattention Test and 40 patients were subjected to an 8-item version of the Behaviour Inattention Test, besides the Baking Tray Task and the personal neglect test. RESULTS: The Baking Tray Task was more sensitive than the 3-item Behaviour Inattention Test, but the 8-item Behaviour Inattention Test was more sensitive than the Baking Tray Task. The best combination of any 3 tests was Baking Tray Task, Reading an article, and Figure copying; the 2 last-mentioned being a part of the 8-item Behaviour Inattention Test. CONCLUSION: Multi-item tests detect more cases of neglect than do single tests. However, it is tiresome for the patient to undergo a larger test battery than necessary. It is also time-consuming for the staff. Behavioural tests seem more appropriate when assessing neglect. The Baking Tray Task seems to be one of the most sensitive single tests, but its sensitivity can be further enhanced when it is used in combination with other tests.  相似文献   
3.
The monoclonal antiparathyroid antibody E11 reacts with a glycoprotein of high molecular weight, which acts as a calcium receptor on the surface of parathyroid cells and mediates calcium regulation of parathyroid hormone (PTH) release. Reduced expression of the calcium receptor has been implicated as a cause of the defect in PTH regulation in the pathological parathyroid parenchyma of patients with hyperparathyroidism (HPT). The present study evaluated the efficacy of immunostainings with the E11 antibody in comparison with routine histopathological methods including staining by the oil red O technique for histological discrimination between normal and pathological parathyroid glands. Parathyroid tissue from euparathyroid individuals invariably presented intense and homogeneous surface staining, with the antibody on virtually all chief cells, while the pathological glands from patients with HPT consistently showed heterogeneous and reduced immunostaining. Even minimally enlarged pathological glands from individuals with mild hypercalcemia and the normal-sized glands associated with adenomas displayed parathyroid chief cells with reduced antibody reactivity. The monoclonal antiparathyroid antibody should constitute a useful tool in parathyroid histopathology not only by its ability to identify the parathyroid tissue, but also by directly demonstrating the functionally normal and abnormal cells within the parathyroid tissue.  相似文献   
4.
Two partially overlapping 19 and 22 amino acids long peptides representing a highly immunogenic site of the transmembranous glycoprotein (gp41) of human immunodeficiency virus (HIV) were used as antigen in ELISA tests. The results of antibody determination with this assay were compared with those of three or more conventional ELISAs and Western blot (WB) tests and radioimmunoprecipitation assay. Twenty-six sera from patients with AIDS or LAS and from asymptomatic carriers of HIV infection all showed a pronounced reaction in the peptide ELISA as well as positive results with other tests. In contrast, 27 sera from laboratory workers and blood donors were negative by all tests. A group of 39 blood donor sera, which had shown false positive or ambiguous results in the ELISAs and sometimes in WB tests employed for confirmation, also were negative in all cases with the peptide ELISA. Consecutive samples collected from individuals with primary HIV infection were also analyzed. In 6 out of 9 cases, the peptide ELISA revealed an antibody response within one month after onset of clinical symptoms and sensitivity for antibody detection equaled that of other ELISA tests. Eight sera from five West African persons infected with HIV-related viruses did not react in the peptide ELISA, reflecting differences in properties of the envelope components. The peptide ELISA used in this study appears to represent a simple technique employing chemically synthesized antigen for accurate and sensitive estimation of antibodies to the HIV group of nontransforming human retroviruses.  相似文献   
5.
A flavivirus microarray was developed for detection and identification of yellow fever (YF), West Nile, Japanese encephalitis (JE), and the dengue 1-4 viruses, which are causing severe human disease all over the world. The microarray was based on 500-nucleotide probe fragments from five different parts of the seven viral genomes. A low-stringent amplification method targeting the corresponding regions of the viral genomic RNA was developed and combined with hybridization to the microarray for detection and identification. For distinction of the generated virus-specific fluorescence-patterns a fitting analysis procedure was adapted. The method was verified as functional for all seven flaviviruses and the strategy for the amplification, combined with the long probes, provided a high tolerance for smaller genetic variability, most suitable for these rapidly changing RNA viruses. A potentially high detection and identification capacity was proven on diverged strains of West Nile and dengue viruses. The lower limit for detection was equivalent, or better, when compared to routinely used RT-PCR methods. The performance of the method was verified on human patient samples containing dengue viruses, or normal human serum spiked with YF or JE viruses. The results demonstrated the ability of the flavivirus microarray to screen simultaneously a sample for several viruses in parallel, in combination with a good lower limit of detection.  相似文献   
6.
Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established.  相似文献   
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8.
OBJECTIVE: To investigate hand problems in patients with systemic lupus erythematosus (SLE) and to explore consequences on the ability to perform daily activities. METHODS: One hundred nine patients with SLE completed a questionnaire assessing hand problems in terms of deficits in body structures, e.g., joints, and body functions including pain, grip force, and other physiologic functions of the hand, the Health Assessment Questionnaire (HAQ), and the Simple hand test. Patients who stated problems in hand function answered questions about performance of daily activities and to what extent different deficits in body structures and body functions interfered. RESULTS: Seventy-three percent of patients experienced hand problems and 42% reported interference with performance of daily activities. Problems from body structures of the hand were distributed relatively evenly over joints and tendons/muscles. Reduced grip force and activity-induced pain were the most commonly reported problems in body functions. The most affected activity area was productivity, namely household tasks, work at home, work/study, and child care; least affected was self-care. Reduced grip force followed by fumbling and pain were the most frequently reported body functions to create difficulties in performing daily activities. When comparing patients with and without difficulties in performing daily activities, there were significant differences in problems from tendons/muscles, joints in the thumb, reduced force, stiffness, fumbling, numbness/tingling, and the HAQ. CONCLUSION: A majority of the study group had hand problems and almost half of the group experienced difficulties in performing daily activities due to SLE. The most affected activity area was productivity, where reduced grip force, fumbling, and pain were the most interfering body functions.  相似文献   
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Background  

A better understanding of the relationship between treatment-seeking for alcohol problems and personality traits could give useful insight in factors promoting or hindering treatment for alcohol use disorders (AUD). The aim of this study was to analyze the associations between treatment-seeking for AUD, personality traits, and psychiatric co-morbidity in women. The study was based on pooled cross-sectional data from three population based samples and one clinical sample (n = 1,339). Comparisons were made between treated and untreated women with AUD, and between those with resolved and unresolved AUD.  相似文献   
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