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31.
Taylor  GA; Fitz  CR; Miller  MK; Garin  DB; Catena  LM; Short  BL 《Radiology》1987,165(3):675-678
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis.  相似文献   
32.
Chondromalacia patellae: assessment with MR imaging   总被引:10,自引:0,他引:10  
Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.  相似文献   
33.
Mediastinal tumors: biopsy under US guidance   总被引:8,自引:0,他引:8  
Percutaneous biopsies of mediastinal tumors were successfully performed under sonographic guidance in 14 of 21 patients. In 10 of 11 malignant lesions, malignancy was determined by means of cytologic and histologic examination of the specimens obtained. A histologic diagnosis was reached in seven patients with malignant mediastinal tumors, including all four cases of Hodgkin lymphoma. Mediastinal biopsy under sonographic guidance is a technically simple, rapid, and accurate procedure, but its application is limited to tumors of the anterior mediastinum.  相似文献   
34.
Ractopamine [1-(4-hydroxyphenyl-2-(1-methyl-3-(4-hydroxyphenyl)propylamino)ethanol] enhances protein accretion in skeletal muscle (sm) of pigs. Experiments were conducted to elucidate fractional protein synthesis (FSR) and mRNA abundance for alpha-actin in sm of pigs fed a 16% protein diet containing 20 parts/million ractopamine for 21 days. Pigs were infused for 6 h with [14C]lysine (80 microCi/h.pig); after infusion pigs were killed, and longissimus dorsi muscle samples were obtained for RNA isolation and measurement of [14C]lysine incorporation. FSR was determined in vivo by incorporation of [14C]lysine from the muscle free amino acid pool into purified sm alpha-actin. FSR of sm alpha-actin was 55% greater in ractopamine-treated pigs than in controls. Relative mRNA abundance of alpha-actin was determined by dot blot hybridization of 0.1-0.4 microgram RNA to human sm alpha-actin [32P]cDNA probe. Longissimus dorsi alpha-actin mRNA abundance was 2-fold greater in pigs fed ractopamine. Sm RNA was translated in vitro using a cell-free assay to determine pretranslational effects on other muscle proteins. Effects of ractopamine on muscle protein synthesis are not specific to sm alpha-actin, because other muscle proteins also were increased using the in vitro translation assay. These results indicate that the increase in sm accretion in pigs fed ractopamine is due in part to an increase in myofibrillar protein synthesis and that some of the increase can be accounted for by an increase in mRNA abundance for sm alpha-actin.  相似文献   
35.
Occult cerebral vascular malformations: high-field MR imaging   总被引:4,自引:0,他引:4  
Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions.  相似文献   
36.
Classification of familial amyloidosis by the chemical natureof the fibrillar protein has become possible. Most such amyloidogenicproteins so far recognized are variant transthyretins, but twokindreds with the same apolipoprotein AI modification have beenreported. We describe the clinical features of another suchfamily in whom petechial skin rash appeared to be a marker forthe disease, which was non-neuropathic and of the Ostertag-type.Immunohistochemistry showed the protein to be apolipoproteinAI, but allele-specific DNA amplification indicated that itwas not the Arg26 variant previously identified.  相似文献   
37.
BACKGROUND: Treatment of hemophilia patients with recombinant factor VIII concentrates has not previously been associated with anaphylaxis. STUDY DESIGN AND METHODS: A 5-week-old boy with severe hemophilia A developed dyspnea, cyanosis, hypotension, and a diffuse urticarial rash following treatment with a recombinant factor VIII (Recombinate). To identify the cause of anaphylaxis in this patient, the vial lot was examined for the presence of endotoxin, and a checkerboard immunoblotting technique was used to test serum and/or plasma samples from the patient and mother for the presence of antibodies (IgA, IgG, IgE, and IgM) to Recombinate-related antigens (recombinant factor VIII, von Willebrand factor, human serum albumin, Chinese hamster ovary proteins, bovine serum albumin, mouse monoclonal anti-human factor VIII, polyethylene glycol 3350), and to ethylene oxide, the agent used to sterilize the infusion equipment. RESULTS: No immune response directed against the Recombinate-related antigens or ethylene oxide that could be associated with the anaphylactic reaction was identified. Endotoxin was not present upon rabbit pyrogen testing of the therapeutic product. CONCLUSION: These studies failed to show any association between Recombinate and the onset of the allergic reaction. This seems to be the first reported case of anaphylaxis following the infusion of a recombinant form of factor VIII concentrate.  相似文献   
38.
Discrepancies in reverse ABO typing due to prozone   总被引:5,自引:0,他引:5  
Three group O sera manifesting prozone in reverse ABO tests are reported. All were implicated in erroneous blood typing results. One sample failed to react with A1 red cells (RBCs) in immediate-spin (IS) tests, had anti-A and -B titers of 8192 and 2048, respectively, by indirect antiglobulin technique (IAT), and was from a diabetic patient; the parenteral administration of A substance present in porcine insulin is a possible cause of hyperimmunity in this case. The second sample was from the recipient of a single unit of group B fresh-frozen plasma; the serum anti-A and -B titers were 10,240 by IAT, but only weak reactions with A1 and B RBCs were noted in routine IS reverse typing tests; the hyperimmunity in the patient concerned was likely due to crossreacting anti-A, B stimulated by B-active glycoproteins and/or glycolipids in the transfused plasma. The third serum also had anti-A and anti-B IAT titers of 10,240 but did not react with A1 and B RBCs by IS; the hyperimmunity in this case may be related to sepsis from intestinal flora carrying A- and/or B-like antigens. These antibodies lysed A1 and/or B RBCs in tests incubated at room temperature (RT) and strongly agglutinated those RBCs by IS when diluted 10-fold with saline. The absence of the prozone phenomenon in tests with RBCs suspended in diluents containing EDTA is consistent with the previously published mechanism for anti-A prozone: namely, the steric hindrance of agglutination by the C1 component of human complement.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
39.
Previous studies have reported markedly lower biological potency of D-T3 than would be predicted from its relative affinity for the specific nuclear L-T3 receptor as measured in vitro. Studies were undertaken to define the basis of this discrepancy. In vitro studies of the relative binding affinities of [125I]L-T3 and [125I]D-T3 using either whole nuclei or partially purified solubilized receptor confirmed several previous reports which had indicated only small relative differences. The mean L/D binding ratio of all in vitro studies was 1.43. In contrast, we determined from measurement of final alpha-glycerophosphate dehydrogenase activity that the potency ratio (L/D) after seven daily injections of graded doses of L- and D-T3 was 6.7 for liver, with 95% confidence limits of 4.1 to 10.8, and 15.9 for heart, with 95% confidence limits of 5.1 to 50.2. Difference in biological potency could not be attributed to differences in the metabolism of L- and D-T3. Thus, tracer [125I]L- and [125I]D-T3 studies showed that the mean residence time, t, of L-T3 was not different from that of D-T3 [10.6 +/- (SE) 3.1 h vs. 11.4 +/- 3.8 h]. The MCR for L-T3 was 19.1 +/- 4.4 ml/h . 100 g BW and for D-T3, 26.1 +/- 5.6 ml/h . 100 g BW. The volume of distribution of L-T3 (181 ml/100 g BW) was 68% that of D-T3 (263 ml/100 g BW), in part owing to the 27% greater plasma binding (bp) of L-T3. Moreover, the calculated free hormone clearance (MCR X bp) of D-T3 was only 8% greater than for L-T3. Throughout the 24 h after injection of the [125I]L- or D-T3, concentrations of the D-enantiomer in liver were almost twice those of [125I]L-T3, whereas in heart [125I]D-T3 concentrations were half or less those of [125I]L-T3. Nevertheless, in both liver and heart, the integrated nuclear occupancy of L-T3 was 5 to 6 times that of D-T3, approaching the ratio in biological potency observed in the tissues. Thus, selective nuclear binding of L-T3 vs. D-T3 in vivo appears to be a major determinant in the relative biological effects of these enantiomers.  相似文献   
40.

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.  相似文献   
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