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1.
Human eosinophils produce a large number of cytokines, including immunoregulatory cytokines. Given that eosinophils store and release interleukin (IL)-4, a key cytokine in the pathogenesis of allergic inflammation, and that IL-4 and IL-13 share common biological functions, we investigated the possibility that IL-13 may be synthesized by these cells. Using flow cytometry and immunocytochemistry, we show that eosinophils synthesize and store IL-13. Granule localization was demonstrated after subcellular fractionation, and IL-13 immunoreactivity was localized to crystalloid, granule-enriched fractions. Furthermore, electron microscopic analyses specifically localized IL-13 to the dense cores of bicompartmental secondary granules. Upon CD28 ligation, IL-13 was released by eosinophils, whereas a combination of CD28 and immunoglobulin A complexes resulted in decreased IL-13 secretion. Furthermore, eosinophil-derived IL-13 exerts a biological effect, inducing CD23 expression on B cells. By having the capacity to synthesize and release IL-13, eosinophils may participate in the development and maintenance of the T helper cell type 2 response, a prominent feature of allergic diseases.  相似文献   
2.
We describe a 77‐year‐old female with hypertrophic cardiomyopathy in whom live/real time three‐dimensional transesophageal echocardiography (3DTEE) provided incremental value over two‐dimensional transthoracic and transesophageal echocardiography (2DTTE, 2DTEE) and three‐dimensional transthoracic echocardiography (3DTTE) in making a more comprehensive assessment and a more confident diagnosis of caseous mitral annular calcification. 3DTEE revealed a portion of the mass to consist of small, multiple, highly echogenic discrete band‐like and punctate areas within a relatively much less echogenic stroma and surrounded by a well defined highly echogenic border. This appearance correlated with the pathological findings of calcific granules/strands located in a liquefied or semiliquefied interior providing a typical toothpaste like appearance. The highly echogenic outer border represented the residual outer portion or rim of the calcific mass which did not undergo liquefaction. These findings on 3DTEE which correlated with the toothpaste like appearance seen at surgery were not visualized on 2DTTE, 2DTEE, and 3DTTE. (Echocardiography 2010;27:1147‐1150)  相似文献   
3.

Objective

The purpose of this study was to compare the relationship between flexion endurance capacity and joint position error in participants with or without chronic neck pain (CNP).

Methods

Sixty-one CNP and 60 asymptomatic volunteers participated in this cross-sectional, case-control, and correlational analysis study. The measured variables included absolute and constant joint repositioning errors in the sagittal and horizontal directions, clinical flexor endurance test score, pain intensity, and neck disability index.

Results

The groups did not statistically differ in flexion endurance (P > .05). The CNP group had a smaller absolute error on the right (P < .01) and left (P = .01) rotation and an overshooting error pattern in the flexion direction (P < .05). But the asymptomatic group did not exhibit any over-/undershooting pattern tendency (P > .05). Although flexion endurance was not correlated with any of the joint repositioning error components in either group, pain and disability scores were significantly correlated with left rotation absolute error (r = –0.34 and ρ = –0.37, respectively).

Conclusion

The clinical cervical flexor endurance test, ignoring the relative contribution of the deep and superficial groups of muscles, may not efficiently characterize CNP patients.  相似文献   
4.
Current oral cholera vaccines induce lower levels of protective efficacy and shorter durations of protection in young children than in adults. Immunity against cholera is serogroup specific, and immune responses to Vibrio cholerae lipopolysaccharide (LPS), the antigen that mediates serogroup-specific responses, are associated with protection against disease. Despite this, responses against V. cholerae O-specific polysaccharide (OSP), a key component of the LPS responsible for specificity, have not been characterized in children. Here, we report a comparison of polysaccharide antibody responses in children from a region in Bangladesh where cholera is endemic, including infants (6 to 23 months, n = 15), young children (24 to 59 months, n = 14), and older children (5 to 15 years, n = 23) who received two doses of a killed oral cholera vaccine 14 days apart. We found that infants and young children receiving the vaccine did not mount an IgG, IgA, or IgM antibody response to V. cholerae OSP or LPS, whereas older children showed significant responses. In comparison to the vaccinees, young children with wild-type V. cholerae O1 Ogawa infection did mount significant antibody responses against OSP and LPS. We also demonstrated that OSP responses correlated with age in vaccinees, but not in cholera patients, reflecting the ability of even young children with wild-type cholera to develop OSP responses. These differences might contribute to the lower efficacy of protection rendered by vaccination than by wild-type disease in young children and suggest that efforts to improve lipopolysaccharide-specific responses might be critical for achieving optimal cholera vaccine efficacy in this younger age group.  相似文献   
5.

Aims

Compare physical activity (PA) levels in adults with and without type 1 diabetes and identify diabetes-specific barriers to PA.

Methods

Forty-four individuals with type 1 diabetes and 77 non-diabetic controls in the Coronary Artery Calcification in Type 1 Diabetes study wore an accelerometer for 2?weeks. Moderate-to-vigorous physical activity (MVPA) was compared by diabetes status using multiple linear regression. The Barriers to Physical Activity in Type 1 Diabetes questionnaire measured diabetes-specific barriers to PA, and the Clarke hypoglycemia awareness questionnaire measured hypoglycemia frequency.

Results

Individuals with type 1 diabetes engaged in less MVPA, fewer bouts of MVPA, and spent less time in MVPA bouts per week than individuals without diabetes (all p?<?0.05), despite no difference in self-reported PA (p?>?0.05). The most common diabetes-specific barrier to PA was risk of hypoglycemia. Individuals with diabetes reporting barriers spent less time in MVPA bouts per week than those not reporting barriers (p?=?0.047).

Conclusions

Individuals with type 1 diabetes engage in less MVPA than those without diabetes despite similar self-reported levels, with the main barrier being perceived risk of hypoglycemia. Adults with type 1 diabetes require guidance to meet current PA guidelines and reduce cardiovascular risk.  相似文献   
6.

Aim  

To test the reliability and validity of the translated version of the knowledge, attitude and practice (KAP) questionnaire on immunization among Arabic parents.  相似文献   
7.
We report a young patient with post traumatic acquired thoracic aortic coarctation in whom three‐dimensional transthoracic echocardiography (3DTTE) demonstrated incremental value over two‐dimensional transthoracic echocardiography (2DTTE). 3DTTE showed (1) en face views of the obstruction site that showed a markedly narrowed, roughly circular orifice measuring 0.33 cm2 in area, (2) echogenic tissue encroaching on the graft lumen consistent with fibrosis/thrombus, and (3) no graft protrusion into the aortic lumen, only hypermobility of the medial portion of the graft. These important findings were not detected by 2DTTE. (Echocardiography 2010;27:470‐472)  相似文献   
8.
Smad proteins transduce signals carried by the transforming growth factor beta (TGF-beta) cytokine superfamily from receptor serine/threonine kinases at the cell surface to the nucleus, thereby affecting cell proliferation, differentiation, as well as pattern formation during early vertebrate development. Smad4/DPC4, located at chromosome 18q21, was identified as a candidate tumor suppressor gene that is inactivated in nearly half of all pancreatic carcinomas. For functional characterization of Smad4, a recombinant adenovirus encoding Smad4 (Ad-Smad4) was generated. When Smad4 was expressed in Smad4-null breast carcinoma cell line MDA-MB-468 using the recombinant adenovirus, TGF-beta signaling was restored as determined by TGF-beta-dependent activity of plasminogen activator inhibitor 1 promoter and p21 expression. Infection with Ad-Smad4 in the presence of TGF-beta1 also resulted in an altered cell morphology that coincided with enhanced beta1 integrin expression and reduced efficiency of colony formation in soft agar. In agreement with increased p21 expression, Smad4-expressing cells showed modest reduction in S phase. However, Smad4 expression did not lead to induction of apoptosis under normal culture conditions. Interestingly, when Smad4-expressing cells were detached and incubated in suspension, they underwent rapid apoptosis in a TGF-beta-dependent manner. Induction of apoptosis caused by loss of anchorage is known as anoikis. Anoikis is believed to prevent colonization elsewhere of detached cells. Additional characterization revealed an increase in the level of focal adhesion kinase 2 (or Pyk2) and activation of caspases 2, 3, 6, and 8 during anoikis because of Smad4 expression and restoration of TGF-beta signaling. Because resistance to anoikis in tumor cells is thought to contribute to metastasis, our data suggest a functional basis for the strong correlation between defects in Smad4 and development of malignancy.  相似文献   
9.
This study aimed to identify changes in knowledge and practices learned to prevent dengue fever in two areas of Catanduva, S?o Paulo State, from 1999 to 2001: a study area and a control area. The study included an initial quantitative survey, qualitative research, a preliminary diagnosis presented to the community to launch a discussion aimed at defining future actions, implementation of the actions in the study area with community participation (but without changes in the control area), and a final comparison of the two areas. Changes in the study area included: vector control workers began demonstrating preventive measures without removing potential breeding places or using larvicide; use of educational aids specific to the local reality; activities related to the residents priorities; and activities such as music, theater skits, scavenger hunts, and games to demonstrate the vector cycle. Potential domiciliary breeding sites were significantly reduced; the proportion of houses without breeding sites was significantly increased; and there was an increase in the percentage of individuals who recognized the larval form of the vector in the study area as compared to the control area.  相似文献   
10.
Three-dimensional (3D) high-resolution ultrasonography has proved to be useful for in vitro assessment of cartilage remodeling due to osteoarthritis. The diagnosis is performed by computation of the mean thickness of the cartilage, which reveals hypertrophy or thinning, and by 3D reconstruction of the data, which provides essential information about the size, extent, and localization of the lesion. In both cases, preliminary segmention of the cartilage is necessary. This article proposes an algorithm for automatic segmentation of the cartilage from 3D ultrasonic acquisitions of the rat patella, which includes the detection of the cartilage surface and the cartilage/bone interface. The method was designed on the assumption of regularity and smoothness of the interfaces. The use of a global threshold was sufficient to separate the patella area from the background. The cartilage/bone interface was detected by selection of regions of interest (ROIs) encompassing the interface, followed by the detection of the interface within these ROIs using the graph theory. The method was applied to 162 samples. The detection accuracy was judged to be very good or good in 99% of the cases for the cartilage surface and in 86% of the cases for the cartilage/bone interface. The mean cartilage thickness value in the central part of the patella obtained from the automatic detection method was compared to that obtained manually. The coefficient of correlation between the two measurements was 0.92. These results show that our method is reliable. Thus, fast processing of a large number of acquisitions and a more complete analysis of the cartilage surface become possible.  相似文献   
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