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91.
92.
Adeno-associated virus (AAV) vector system has several useful advantages with regard to in vitro and in vivo gene transfer. However, their usages have been limited by cumbersome and labor-intensive vector production in the traditional method. To overcome limitations in AAV production, in this report, we explored the possibility of generating AAV packaging cell line, 293T R/C.VA.E2A.E4. cells, by using lentivirus-mediated transduction of Rep/Cap gene of AAV-2, VA RNA, E2A, and E4 genes of Ad5 into 293T cells. In packaging cell lines, it is important that supply of the AAV vector can be stably performed for long time. We showed that the 293T R/C.VA.E2A.E4. cells have stably maintained the transduced components after more than 10 passages and yielded high-titer AAV vectors, and the titer of AAV vectors did not decline even if culture of the packaging cells was continued for long time. The Rep/Cap and E4 gene products caused no remarkable cytotoxicity. The 293T R/C.VA.E2A.E4. cells might be able to tolerate the Rep/Cap and E4 gene products, or have less copy numbers of the Rep/Cap and E4 genes than the traditional method. Moreover, we showed that the AAV vectors derived from 293T R/C.VA.E2A.E4. cells infected the primary human CD34+ haematopoietic progenitor cells with high efficiency (50-70%). In the 293T R/C.VA.E2A.E4. cells, the AAV vectors can be generated by the transfection of one AAV vector plasmid, and large-scale AAV production can be easily achieved. It is important that cumbersome, variable, and costly transfection is avoided.  相似文献   
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94.
Microscopic polyangiitis associated with diffuse panbronchiolitis   总被引:1,自引:0,他引:1  
There are several case reports of systemic vasculitis associated with chronic suppurative lung diseases. We describe a 46-year-old female, previously diagnosed as having diffuse panbronchiolitis (DPB), presenting with hemosputum and dyspnea. Her serum titer of MPO-ANCA was positive together with a high titer of BPI-ANCA. Chest X-ray and chest CT scan showed pulmonary hemorrhage, and the renal biopsy specimen revealed necrotizing, crescentic glomerulonephritis. She was diagnosed as having ANCA-associated vasculitis, and more specifically, microscopic polyangiitis accompanied by DPB. She was treated with methylprednisolone pulse therapy, followed by intravenous cyclophosphamide. This case suggested a possible association with chronic bacterial infection, which may play a role in the pathogenesis of ANCA-associated vasculitis.  相似文献   
95.
During the epidemic of severe acute respiratory syndrome in 2003, a 27-year- old Japanese woman presented a high fever and acute respiratory distress with pulmonary infiltrates after traveling to a high-risk area. An alternative diagnosis was made as Epstein-Barr virus-associated hemophagocytic syndrome, based on the proliferation of macrophages with hemophagocytosis in the bone marrow and Epstein-Barr viral marker profiles. Virus-associated hemophagocytic syndrome in an international traveler should be included in the differential diagnosis of severe acute respiratory syndrome.  相似文献   
96.

Background

Atopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malassezia globosa was identified as the major histamine releasing antigen in human sweat.

Methods

The full length cDNA of the counterpart of MGL_1304 in Malassezia restricta (Mala r 8), was cloned by degenerate PCR and rapid identification of cDNA ends (RACE). Recombinant MGL_1304, and its counterparts, Mala s 8 (produced by Malassezia sympodialis) and Mala r 8 were prepared, and compared in their allergenicities by dot blot analysis and histamine release tests with sera and basophils of patients with AD.

Results

The identities between MGL_1304 and Mala s 8, MGL_1304 and Mala r 8, and Mala s 8 and Mala r 8 were 68%, 78%, and 76%, respectively, in protein sequences. Dot blot analysis revealed that the level of IgE binding to Mala s 8 was higher than that of MGL_1304. However, histamine release tests revealed that MGL_1304 and Mala r 8 possessed higher activity than Mala s 8. In addition, the crude lysate of M. globosa showed higher histamine release ability than that of M. sympodialis.

Conclusions

Patients with AD showed hypersensitivities against MGL_1304 and its homologs. However, the allergenicities of the homologs are variable and the histamine release activities may be different from the solid-phase binding activities for IgE. Sweat allergy should be carefully evaluated with biological activities of MGL_1304 and its homologs of other Malassezia fungi residing on the skin.  相似文献   
97.
Ambulatory electrocardiographic monitoring was performed in 18 children with a congenital complete heart block (CCHB). They had no cardiac structural anomalies. These patients could be divided into 3 groups according to the pattern of fluctuations in beat-to-beat ventricular rates. Type 1 patients showed rapid and transient fluctuations and demonstrated a high correlation between atrial and ventricular rates. Type 3 patients showed a constant ventricular rate and little variation through the 24 hour period and there was no appreciable correlation between atrial and ventricular rates. Twelve of 18 patients had additional arrhythmias. A few sporadic ventricular premature contractions (VPCs) were found in 9 patients, and bigeminy of VPCs or ventricular tachycardias were seen in 2 patients during exercise. Frequent and sudden prolongation of RR intervals was found during sleep in 3 patients. The longest intervals of ventricular asystoles were 7.2, 3.2 and 3.2 sec, respectively. The mechanism of this phenomenon appeared to be not only an exit block, but also arrest or a lack of automaticity of a subsidiary pacemaker. One of these patients developed frequent Stokes-Adams attacks. Type 3 patients with sudden prolongation of RR intervals and/or frequent ventricular arrhythmias should be under careful observation. Ambulatory electrocardiographic monitoring is recommended for children with CCHB for evaluation of potential risk factors for Stokes-Adams attacks.  相似文献   
98.
We report a patient with spontaneous rupture of the common bile duct. This is an extremely rare condition which produces free leakage of bile into the peritoneal cavity. There has been no previous report concerning the formation of a large retroperitoneal encapsulation of bile. The preoperative diagnosis in our patient was very difficult and endoscopic retrograde pancreatocholangiography and cystography by ultrasound guidance were helpful.  相似文献   
99.
To delineate the effects of aging on basal and glucose-stimulated secretion of islet amyloid polypeptide (IAPP), we compared the basal level of plasma IAPP and its response to an oral glucose load in elderly subjects with those of young subjects. Plasma IAPP level was determined by radioimmunoassay. Basal level of plasma IAPP in 20 elderly subjects (mean age 63 yr) was 5.3 +/- 0.4 pmol/l, which was not significantly different from 5.0 +/- 0.3 pmol/l in 22 young subjects (mean age 26 yr). Plasma glucose levels after an oral glucose load in elderly subjects (n = 8, mean age 67 yr) and young subjects (n = 8, mean age 29 yr) were within normal limits. However, the plasma glucose response in the aged group was significantly higher than that in the young group. The plasma insulin response to a glucose load in elderly subjects was not different from that in young subjects. The plasma IAPP level in the aged group significantly increased from 5.3 +/- 0.5 to 16.4 +/- 2.3 pmol/l 120 min after the oral glucose load. This result was quite similar to that in the young group whose plasma IAPP level increased from 4.9 +/- 0.5 to 14.1 +/- 1.5 pmol/l 120 min after the glucose load. We concluded that the basal level of plasma IAPP and its response to glucose were not affected by aging.  相似文献   
100.
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