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71.
BACKGROUND: Exposure to acute stressors modulates both innate and acquired immune function. However, little is known about whether stress has the potential to modulate the pathogenesis of allergic rhinitis. OBJECTIVES: To determine the effects of acute restraint stress on the initiation of allergic rhinitis in a murine model. METHODS: CBA/J mice were repeatedly intranasally sensitized with phospholipase A2 (PLA2) from honeybee venom without adjuvant. Restraint stress was applied using uniform cylinders once a week for a continuous 8-hour period, on five occasions in total. Production of PLA2-specific antibodies and degree of nasal and blood eosinophilia were compared between stressed and control mice. RESULTS: Repeated intranasal sensitization with PLA2 induced PLA2-specific IgE and marked eosinophilia in both the nose and blood in CBA/J mice. Exposure to restraint stress significantly inhibited production of PLA2-specific IgE, IgG1 and IgG2a. Conversely, the stress exerted no significant effect on eosinophilia. CONCLUSIONS: Exposure to acute restraint stress inhibits antigen-specific antibody production, but not local or systemic eosinophilia. The results of this study suggest that acute stress has the potential to modulate the initiation of allergic rhinitis.  相似文献   
72.
73.
Whole blood samples of known methylene tetrahydrofolate reductase (MTHFR) genotypes from 24 individuals were examined at site C677T. Their amplified DNA products were assessed by two-color fluorescence cross-correlation measurements and agarose gel electrophoresis/capillary gel electrophoresis. DNA subpopulations were identified which were not associated with the proper genotype by primer combinations and cycling conditions called multiplexes. We confirmed that DNA analysis by two-color fluorescence cross-correlation measurements allowed the detection of fluorescence signals specifically associated with the proper genotypes in a mixture of amplified nontarget DNA molecules without DNA sizing. The measurement approach does not require complex, follow-up mathematical analysis and is applicable to any single nucleotide polymorphisms. The simple immunogenetic model showed how the approach works to reveal specific DNA target by preventing detection of nontarget DNA. Under those experimental conditions, a new ultrasensitive, and specific method for clinical immunologists is born.  相似文献   
74.
A female patient with unilateral gonadal dysgenesis was a mosaic for three cell lines, 45,X/46,X, + marI/46,X, + marII, including two different marker chromosomes. DNA analysis using 17 Y-specific DNA probes revealed that each marker consists of different segments of the Y chromosome.  相似文献   
75.
Polymerase chain reaction (PCR) was used to detect Rickettsia tsutsugamushi-specific DNA in clinical specimens. The primer pair used for PCR was designed from the nucleotide sequence of the gene encoding the 56-kDa antigen of the Gilliam strain. Theses primers led to a 78-bp fragment by amplifying the genomic DNAs from five serovariants, i.e., the Gilliam, Karp, Kato, Kawasaki, and Kuroki strains of R. tsutsugamushi, and also the DNA from blood clots of patients with scrub typhus, even at the early stage of onset of the disease. This indicates that this method is suitable for the diagnosis of scrub typhus.  相似文献   
76.
This is a report of a 27-year-old woman with an unusual de novo chromosomal abnormality. Mosaicism was identified in peripheral blood cells examined by standard G-bands by trypsin using Giemsa (GTG) analysis and fluorescence in situ hybridization (FISH) analysis with chromosome-18 region-specific probes, 46,XX,del(18)(pter → q21.33:)[41], 46,XX,r(18)(::p11.21 → q21.33::)[8], and 46,XX,der(18)(pter → q21.33::p11.21 → pter)[1]. On the other hand, the karyotype of periodontal ligament fibroblasts was nonmosaic, 46,XX, der(18)(pter → q21.33::p11.21 → pter)[50]. All cell lines appeared to be missing a portion of 18q (q21.33 → qter). The pattern of the dup(18p)/del(18q) in the rod configuration raises the possibility of an inversion in chromosome 18 in one of the parents. However, no chromosomal anomaly was detected in either parent. The most probable explanation is that de novo rod and ring configurations arose simultaneously from an intrachromosomal exchange. The unique phenotype of this patient, which included primary hypothyroidism and primary hypogonadism, is discussed in relation to her karyotype.  相似文献   
77.
Germline mutations in patients with familial adenomatous polyposis were analyzed by polymerase chain reaction (PCR) amplification of the adenomatous polyposis coli gene. PCR products from heterozygous patients for deletions of this gene formed four distinct bands on polyacrylamide gel electrophoresis. The four fragments were subsequently purified and both strands of each fragment were directly sequenced, using an automated DNA sequencer and the same primers as those for PCR amplification. It was found that the two slower migrating fragments were “bulge” heteroduplexes, while the other two were homoduplexes made up of two wild-type strands and two deletion-mutant strands, respectively. The sites of deletions in the adenomatous polyposis coli gene could be exactly determined in four of the five patients. In an attempt to identify deletion-carriers of familial adenomatous polyposis at the presymptomatic stage, a family study was also carried out, and two children were found to have the same mutations as those of their affected parents. The direct sequencing of heteroduplex fragments generated during PCR amplification is a potentially useful method for detecting mutations of not only the adenomatous polyposis coli gene but also many other genes of genetic diseases. © 1993 Wiley-Liss, Inc.  相似文献   
78.
Dialysates from Dermatophagoides farinae were partially purified. Fractionation on HPLC and anion exchange chromatography revealed that the dialysates consisted of 5 major fractions of glycoprotein whose apparent molecular sizes were 5.1, 4.1, 3.2, and less than 1.35 kD on HPLC. The apparent molecular size of two fractions was 5.3 and 2.9 kD on SDS-PAGE. They were basic glycoproteins which had a pI ranging from 7.46 to 8.71 on PAG-IEF. These fractions were allergenic in the RAST and ELISA inhibition tests but not in the skin prick test (SPT). Our results suggest that the dialysates from D. farinae have haptenic properties. The dialysates from D. farinae (low molecular weight) and its 5 fractions bound noncovalently to human serum albumin (HSA) at the free tyrosine residues of HSA. They proved to bind noncovalently to serum proteins and collagens. Once they bound to proteins, the conjugates became allergenic not only in the RAST and ELISA inhibition test but also in the SPT. Our results provide evidence that the dialysates from D. farinae have haptenic properties.  相似文献   
79.
Point of care testing(POCT) is defined as clinical testing done at or near the site of patient treatment and care in the medical field, and includes all clinical test other than those performed at hospital laboratories and outside testing centers. Home testing is also a form of POCT relating to residential medical care. The ratio of clinical tests based on POCT has not tended to increase as rapidly in Japan, although such tests are greatly increasing in the US while clinical tests performed at hospital laboratories are decreasing. POCT products are generally applied to direct analysis of test samples obtained from patients. Since storage, transportation or pretreatment after sampling is not necessary in POCT, test data can be obtained in real time. Therefore, it is important to complete testing immediately after obtaining samples without transporting or storing them, when handling POCT samples. Consideration of POCT as a part of health care services covered by health insurance is the same as in the case of conventional testing. Recent technological innovation has provided a wide variety of POCT products that do not require medical equipment or reagents. Further development of novel, innovative POCT procedures in the near future is promising.  相似文献   
80.
Summary The purpose of this study was to examine whether the ventilatory threshold (Th v) would give the maximal lactate steady state ([1a]ss, max), which was defined as the highest work rate (W) attained by a subject without a progressive increase in blood lactate concentration [1a]b at constant intensity exercise. Firstly, 8 healthy men repeated ramp-work tests (20 W·min–1) on an electrically braked cycle ergometer on different days. During the tests, alveolar gas exchange was measured breath-by-breath, and theW atTh v (W Th v) was determined. The results of two-way ANOVA showed that the coefficient of variation of a singleW Th v determination was 2.6%. Secondly, 13 men performed 30-min exercise atW Th v (Th v trial) and at 4.9% aboveW Th v (Th v + trial), which corresponded to the 95% confidence interval of the single determination. The [1a]b was measured at 15 and 30 min from the onset of exercise. The [1a]b at 15 min (3.15 mmol·1–1, SEM 0.14) and at 30 min (2.95 mmol·1–1, SEM 0.18) were not significantly different inTh v trial. However, the [1a]b ofTh v+ trial significantly increased (P<0.05) from 15 min (3.62 mmol·1–1, SEM 0.36) to 30 min (3.91 mmol·1–1, SEM 0.40). These results indicate thatTh v gives the [1a]ss,max, at which one can perform sustained exercise without continuous [1a]b accumulation.  相似文献   
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