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41.
Kim YS Cheon KA Kim BN Chang SA Yoo HJ Kim JW Cho SC Seo DH Bae MO So YK Noh JS Koh YJ McBurnett K Leventhal B 《Yonsei medical journal》2004,45(1):81-89
In order to develop a structured and objective diagnostic instrument, authors completed: (1) the translation and back translation of the Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and Lifetime Version (K-SADS-PL) and (2) the examination of its validity and reliability of the K-SADS-PL-Korean version (K-SADS- PL) when used with Korean children. A total of 91 study subjects were recruited from child and adolescent psychiatry outpatient clinics. Clinical diagnoses were used as a gold standard for the examination of validity of K-SADS-PL-K. Consensual validity of threshold and sub-threshold diagnoses were good to excellent for attention-deficit/hyperactivity disorder (ADHD), fair for tic and oppositional defiant disorders, and poor to fair for anxiety and depressive disorders. Inter-rater and test-retest reliabilities were fair to excellent for ADHD and tic disorder. The significant correlations between the K-SADS-PL-K and Korean Child Behavior Checklist (K-CBCL) were found, which provided additional support for the concurrent validity of the K-SADS-PL-K. Sensitivities varied according to the diagnostic categories, but specificities remained high over all diagnoses, suggesting that the K-SADS-PL-K is a desirable confirmatory diagnostic tool. The results of this study suggest that the K-SADS-PL-K is an effective instrument for diagnosing major child psychiatric disorders, including ADHD, behavioral disorders and tic disorders in Korean children. Future studies will examine the validity and reliability of the K-SADS-PL-K in larger samples, including adolescents and community samples on a variety of child and adolescent psychiatric disorders. 相似文献
42.
Delivery of a hammerhead ribozyme specifically down-regulates the production of fibrillin-1 by cultured dermal fibroblasts 总被引:4,自引:1,他引:4
Kilpatrick MW; Phylactou LA; Godfrey M; Wu CH; Wu GY; Tsipouras P 《Human molecular genetics》1996,5(12):1939-1944
The hammerhead ribozyme is a small catalytic RNA molecule. Potential
hammerhead ribozymes that possess a catalytic domain and flanking sequence
complementary to a target mRNA can cleave in trans at a putative cleavage
site within the target molecule. We have investigated the potential of
hammerhead ribozymes to down-regulate the product of the fibrillin-1 gene
(FBN1). Fibrillin is a 347 kDa glycoprotein that is a major constituent of
the elastin-associated microfibrils. Mutations in the FBN1 gene are
responsible for Marfan syndrome (MFS), a common systemic disorder of the
connective tissue. Many FBN1 mutations responsible for MFS appear to act in
a dominant-negative fashion, raising the possibility that reduction of the
amount of product from the mutant FBN1 allele might be a valid therapeutic
approach for MFS. A trans-acting hammerhead ribozyme (FBN1-RZ1) targeted to
the 5' end of the human FBN1 mRNA has been designed and synthesized, and
shown to cleave its target efficiently in vitro. FBN1-RZ1 cleavage is
magnesium dependent and efficient at both 37 and 50 degrees C. Delivery of
the FBN1-RZ1 ribozyme into cultured dermal fibroblasts, by receptor-
mediated endocytosis of a ribozyme-transferrin-polylysine complex,
specifically reduces both cellular FBN1 mRNA and the deposition of
fibrillin in the extracellular matrix. These results suggest that the use
of hammerhead ribozymes is a valid approach to the study of fibrillin gene
expression and possibly to the development of a therapeutic approach to
MFS.
相似文献
43.
Studies on the origin of redox enzymes in seminal plasma and their relationship with results of in-vitro fertilization 总被引:3,自引:0,他引:3
Yeung CH; Cooper TG; De Geyter M; De Geyter C; Rolf C; Kamischke A; Nieschlag E 《Molecular human reproduction》1998,4(9):835-839
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide
dismutase (SOD) and catalase-like enzyme activity were quantified in
seminal plasma from normozoospermic patients, men with known distal ductal
occlusion, proven fathers and male partners of couples receiving in-vitro
fertilization (IVF) treatment for both male and female causes. Glutathione
was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme
activities per unit volume were lower in semen from vasectomized men,
suggesting that they did not originate substantially from the testis or
epididymis. The strongest relationships between enzyme activities and
accessory gland markers were between zinc and GRD (r = 0.678), SOD (r =
0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these
enzymes. Only weak relationships between accessory gland markers and
catalase-like activity suggested a multi-glandular source of this enzyme.
There was no relationship between the activity of any of the enzymes in the
IVF patients with their fertilization rates in vitro or the establishment
of pregnancy after IVF. Nor was there any correlation of enzyme activity
with the morphology and percentage of motile spermatozoa in semen or with
the percentage motility of spermatozoa immediately after swim-up or after
overnight incubation. These findings suggest that the protective enzymes in
the seminal plasma are contributed largely by the prostate and little by
the epididymis, and that in most cases of IVF, they have no major influence
on the outcome.
相似文献
44.
Efficient correction for CT image artifacts caused by objects extending outside the scan field of view 总被引:3,自引:0,他引:3
The purpose of this paper is to develop a method of eliminating CT image artifacts generated by objects extending outside the scan field of view, such as obese or inadequately positioned patients. CT projection data are measured only within the scan field of view and thus are abruptly discontinuous at the projection boundaries if the scanned object extends outside the scan field of view. This data discontinuity causes an artifact that consists of a bright peripheral band that obscures objects near the boundary of the scan field of view. An adaptive mathematical extrapolation scheme with low computational expense was applied to reduce the data discontinuity prior to convolution in a filtered backprojection reconstruction. Despite extended projection length, the convolution length was not increased and thus the reconstruction time was not affected. Raw projection data from ten patients whose bodies extended beyond the scan field of view were reconstructed using a conventional method and our extended reconstruction method. Limitations of the algorithm are investigated and extensions for further improvement are discussed. The images reconstructed by conventional filtered backprojection demonstrated peripheral bright-band artifacts near the boundary of the scan field of view. Images reconstructed with our technique were free of such artifacts and clearly showed the anatomy at the periphery of the scan field of view with correct attenuation values. We conclude that bright-band artifacts generated by obese patients whose bodies extend beyond the scan field of view were eliminated with our reconstruction method, which reduces boundary data discontinuity. The algorithm can be generalized to objects with inhomogeneous peripheral density and to true "Region of Interest Reconstruction" from truncated projections. 相似文献
45.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
46.
The localisation of the principal blood group antigens has been studied in human liver. These blood group antigens included the erythrocyte antigens and the antigen of the major histocompatibility complex. This study was performed by the indirect immunofluorescence technique using polyclonal antibodies of human or animal origin and monoclonal antibodies from hybridomas. This study has shown that the normal hepatocyte is lacking in blood group antigens. On the contrary, the biliary cell was rich in antigenic markers: the main antigens expressed were Lewis, Pr, HLA-A and B antigens. In Kupffer cells, only i and HLA-DR antigens were clearly expressed. The endothelial cells of blood vessels mainly show A, B, H, HLA-A and B antigens; HLA-DR and Pr are slightly expressed. HLA-DR antigens were more strongly expressed on veins than on arteries. Dendritic cells have been identified in the portal space of human liver. They bore i and HLA-DR antigens. 相似文献
47.
Bae JW Takahashi I Sasano Y Onodera K Mitani H Kagayama M Mitani H 《Journal of anatomy》2003,203(2):235-241
Matrix metalloproteinases (MMPs) have been implicated in physiological cartilage matrix remodelling as well as in pathological and invasive extracellular matrix remodelling of tissue. Age-related changes in the gene expression patterns of MMPs in mandibular condylar cartilages (MCCs) were analysed. We examined the gene expression patterns of Mmp-8 and -13 and their substrates, Col1a1, Col2a1 and Col10a1, in MCC of growing and ageing rats. Temporomandibular joints of male Wistar rats aged 4, 8, 16 and 32 weeks were subjected to in situ hybridization analysis. Histologically, MMCs showed characteristics of growth plate cartilage at ages 4 and 8 weeks, and more closely resembled articular cartilage thereafter. Mmp-8 was expressed in the cells in all cartilaginous cell layers at ages 4 and 8 weeks, and then was localized only in the mature cells at ages 16 and 32 weeks. Whereas Mmp-13 expression was limited to the lowermost hypertrophic chondrocytes in the growth stage, mature chondrocytes instead of hypertrophic chondrocytes expressed Mmp-13 in adult non-hypertrophic MCC. Because Mmp-8 and -13 expression overlapped with Col2a1 and Col10a1, chondrocytes could play a pivotal role in degradation as well as production of the cartilaginous matrix in MCC. 相似文献
48.
The modifying potential of capsaicin (CAP) on lesion development was examined in a rat multiorgan carcinogenesis model. Groups 1 and 2 were treated sequentially with diethylnitrosamine (DEN) (100 mg/kg, ip, single dose at commencement), N-methylnitrosourea (MNU) (20 mg/kg, ip, 4 doses at days 2, 5, 8, and 11), and N,N-dibutylnitrosamine (DBN) (0.05% in drinking water during weeks 3 and 4). Group 3 received vehicles without carcinogens during the initiation period. Group 4 served as the untreated control. After this initiating procedure, Groups 2 and 3 were administered a diet containing 0.01% CAP. All surviving animals were killed 20 weeks after the beginning of the experiment and the target organs examined histopathologically. The induction of GST-P+ hepatic foci in rats treated with carcinogens was significantly inhibited by treatment with CAP. CAP treatment significantly decreased the incidence of adenoma of the lung but increased the incidence of papillary or nodular (PN) hyperplasia of the urinary bladder. The tumor incidence of other organs, such as the kidney and thyroid, was not significantly different from the corresponding controls. These results demonstrated that concurrent treatment with CAP not only can inhibit carcinogenesis but can also enhance it depending on the organ. Thus, this wide-spectrum initiation model could be used to confirm organ-specific modification potential and, in addition, demonstrate different modifying effects of CAP on liver, lung, and bladder carcinogenesis. 相似文献
49.
A retrospective study of 90 cases of small-sized (less than 3 mm on the printed CT film) acute (within 24 hours) subdural hematoma (SASDH) is presented. From March 1985 to December 1986, the SASDH were immediately operated on (operation rate: 86.0%). From January 1988 to December 1989, we attempted to treat them conservatively (operation rate: 49.1%). The patient population for this study consisted of 38 surgically-treated patients in the first period (Group I), 26 surgically-treated patients in the second period (Group IIs), and 26 conservatively-treated patients in the second period (Group IIc). We compared the clinical features, radiologic findings, and outcome of these 3 groups. The clinical features of Group I, including age, sex, Glasgow Coma Scale (GCS) score on admission, pupillary status on arrival, and interval from injury to the CT, did not differ significantly from those of Group II (P greater than 0.01). The only difference was the timing of the operation. In Group I, 20 patients (52.6%) received an operation within 4 hours, while in Group IIs, only 7 patients (26.9%) underwent surgery within 4 hours (P less than 0.05). The radiologic findings of Group I, including the thickness and volume of the hematoma, the degree of midline shift, and the frequency of skull fracture, also did not differ from those of Group II (P greater than 0.1). However, the outcome of Group II strikingly differed from that of Group I. The mortality rate was 76.3% in Group I, while it was 44.2% in Group II (P less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
50.
Byun BH Lee SW Bae SH Choi JY Kim DG Byun JY Park YM Park DH Kim BS 《Journal of Korean medical science》1999,14(1):97-101
Biliary complications after orthotopic liver transplants are a continuing cause of morbidity and mortality. Biliary stones and sludge are less well known complications of hepatic transplantation, although they have long been recognized. Recently we experienced two cases of biliary stones developed after liver transplantation. One 32-year-old male, who frequently admitted due to recurrent cholangitis, was treated with percutaneous transhepatic biliary drainage and choledochojejunostomy with cholecystectomy. The other 58-year-old male, who had stones in commone bile duct, was treated by endoscopic manipulation. They are in good condition without recurrent bile duct stones or its accompanying complications. Although stones and sludge are relatively infrequent after liver transplantation, surgical or interventional radiologic treatments are usually performed for treatment. 相似文献