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BACKGROUNDCytomegalovirus (CMV) colitis is usually seen in immunocompromised patients with risk factors such as human immunodeficiency virus infection, solid organ transplant, inflammatory bowel disease, or malignancy. Therefore, many clinicians usually do not consider the possibility of CMV colitis in immunocompetent patients. We reported a rare case of segmental colonic hypoganglionosis associated with CMV colitis in an immunocompetent patient. CASE SUMMARYA 48-year-old woman with no underlying disease was admitted to our hospital for severe abdominal pain and constipation. Computed tomography of the abdomen showed diffuse dilatation of the small intestine and the entire colon. Initial sigmoidoscopic findings and result of polymerase chain reaction (PCR) for CMV revealed the compatible findings of CMV colitis, the patient was treated with intravenous ganciclovir. After treatment, sigmoidoscopic findings and CMV PCR results improved. However the patient continued to suffered from constipation. Eight months after the initial admission, patient visited the emergency department with severe abdominal pain and imaging revealed aggravation of fecal impaction and bowel dilatation. We performed subtotal colectomy to control patient’s symptom. Histological examination of the resected specimen showed significantly reduced number of mature ganglion cells in the sigmoid colon compared to that in the proximal colon.CONCLUSIONOur case demonstrates that CMV colitis can develop even in patients with no other underlying disease, and that CMV colitis can be one of the causes for developing colonic hypoganglionosis.  相似文献   
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Purpose

Neisseria meningitidis is a leading cause of bacterial meningitis in young adults. University students, especially those living in dormitories, have been known to be at increased risk of meningococcal disease. We performed a longitudinal study to determine the carriage rates of N. meningitidis and the changes thereof.

Materials and Methods

We recruited Inha University freshmen who were, at that time, admitted to a student dormitory. A pharyngeal swab was taken from all participant who were also asked to complete a questionnaire. This was repeated four weeks later.

Results

A total of 136 students were enrolled at the first culture. After four weeks, 128 students were enrolled, including 106 re-participants. The overall carriage rates changed from 11.8% to 14.1%. In analysis of the 106 re-participants, "visiting to pubs" was associated with carriage of N. meningitis for both the first (p=0.047) and second cultures (p=0.026). Serogroup C was found to be the most frequent serogroup (5 isolates), while 3 isolates were found from serogroup B. The most prevalent PorA types were P1.22,14-6 (4 isolates) and P1.19,15 (3 isolates). The DNA sequences of PorA VR2 were changed in 2 students during prolonged carriage.

Conclusion

The meningococcal carriage rate among first year university students who resided in a dormitory did not significantly increase over 4-week interval between cultures, which is markedly different from those reported in Western studies. Close social contact appeared to be related with carriage. Our data also revealed diversity in PorA types, suggesting the possibility of rapid mutation of the PorA gene during the 4-week interval.  相似文献   
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Most current approaches to multiantigen fluorescent imaging require overlaying of multiple images taken with separate filter sets as a result of differing dye excitation requirements. This requirement for false-color composite imaging prevents the user from visualizing multiple species in real time and disallows imaging of rapidly moving specimens. To address this limitation, here we investigate the use of oligodeoxyfluoroside (ODF) fluorophores as labels for antibodies. ODFs are short DNA-like oligomers with fluorophores replacing the DNA bases and can be assembled in many colors with excitation at a single wavelength. A DNA synthesizer was used to construct several short ODFs carrying a terminal alkyne group and having emission maxima of 410–670 nm. We developed a new approach to antibody conjugation, using Huisgen–Sharpless cycloaddition, which was used to react the alkynes on ODFs with azide groups added to secondary antibodies. Multiple ODF-tagged secondary antibodies were then used to mark primary antibodies. The set of antibodies was tested for spectral characteristics in labeling tubulin in HeLa cells and revealed a wide spectrum of colors, ranging from violet-blue to red with excitation through a single filter (340–380 nm). Selected sets of the differently labeled secondary antibodies were then used to simultaneously mark four antigens in fixed cells, using a single image and filter set. We also imaged different surface tumor markers on two live cell lines. Experiments showed that all colors could be visualized simultaneously by eye under the microscope, yielding multicolor images of multiple cellular antigens in real time.  相似文献   
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BackgroundCondylar cartilage acts as a centre of craniofacial complex growth and magnetic resonance imaging (MRI) is the most suitable examination to differentiate tissues and identify pathological conditions of TMJ. Condylar growth disturbance can alter the maxillofacial morphology, including occlusal relationship, and the affected children may not present symptoms. Although TMJ in children is similar to that in adults, the anterior condylar inclination is straight and increases with age, presenting slight condylar flattening and slight contrast enhancement.ObjectiveThe present work aimed to review the literature focussing to assess how MRI and the development of TMJ can contribute to orthopaedic/orthodontic diagnosis in growing patients.Main resultsMRI can also complement the predictive diagnosis of growth in which the image of a double contour of the condyle reveals proliferation of cartilage cells with immature ossification. Considering that orthodontic therapy usually begins after eruption of permanent teeth, the moment of alternation of the double contour-like structure is close or coincident with the eruption of upper second molars.ConclusionClinically, the advantage of diagnosis of double contour is not to use any ionizing radiation related to scan in these subjects. Therefore, MRI could be a choice for the follow-up of growing patients.  相似文献   
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