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1.

Background

The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.

Methods

A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.

Results

Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.

Conclusions

In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler.  相似文献   
2.
The origins of the projections of the superior colliculus to the dorsal lateral geniculate nucleus and to the pulvinar in Dutch-belted rabbits were investigated using horseradish peroxidase (HRP) methods. Following injections of HRP in the dorsal lateral geniculate nucleus, retrogradely labeled neurons were found in the upper two-thirds of the stratum griseum superficiale of the ipsilateral superior colliculus. Most of the labeled somata were spindle-shaped, and their major axes tended to be perpendicular to the surface of the superior colliculus. In contrast, following injections of the pulvinar, labeled neurons were found in the lower third of the ipsilateral stratum griseum superficiale. In these cases, the labeled somata were larger than those labeled following dorsal lateral geniculate injections and were multipolar in shape.  相似文献   
3.
Preparations of Amsacta moorei entomopox virions were obtained from virus-containing inclusions (VCI) by using a carbonate-thioglycolate solution (pH 10.7–11.5). The virions possessed a uniform coat (“halo”) surrounding the viral envelope and exhibited an RNA polymerase activity. The “halo” could be removed by prolonged exposure to the carbonate-thioglycolate solution. Virions obtained by this treatment, however, possessed low infectivity and no detectable RNA polymerase activity. Removal of the “halo” by trypsin resulted in virions which possessed RNA polymerase activity and relatively high infectivity.Preparations of particles with and without the “halo” were similar in percent DNA, protein per OD260, number of particles per OD260, and RNA polymerase activity. Particles without the “halo,” however, were less dense (1.262 g/cm3) in CsCl than those with the “halo” (1.282 g/cm3) and 15–45 times more infective.Parallel studies of “nonhaloed” Amsacta virions (trypsin-treated) and vaccinia virions showed that both viruses contained similar amounts of protein per OD260, but Amsacta virions contained only 36% of the DNA found in vaccinia.  相似文献   
4.
Sera of 86 patients clinically sensitive to foods were tested by passive sensitization of human and/or monkey lung (127 tests) and the radioallergosorbent test (RAST) (72 tests), using whole-food antigens; the results were compared with skin (prick) testing. Results of the prick test correlated with history in 76% of cases; lung sensitization correlated with history in 37% and with prick test in 57%; and RAST correlated with history in 54% and prick test in 72%. It is concluded that a very large percentage of adverse reactions to foods are IgE-mediated. The prick test is of use in diagnosis, particularly when combined with RAST; the lung sensitization test is technically impractical and not a reliable indicator. The best diagnostic method is careful history with food challenge and withdrawal and rechallenge; the latter is safe except in patients with a history of violent reaction.  相似文献   
5.
In a comprehensive study of 80 patients with vasculitis, 4 had concurrent hepatitis B virus (HBV) infection. Polyarteritis nodosa was present in 2 and in the other 2, cutaneous vasculitis, presenting clinically as palpable or Henoch-Schönlein purpura. In one of these patients skin biopsies demonstrated granular deposits of IgM, C3, C4, and the hepatitis B surface antigen (HBsAg) and electron-dense deposits of aggregated 20-nm particles resembling HBsAg in postcapillary venules. Evidence for circulating HBsAg-immune complexes included increased serum C1q binding activity, decreased serum complement, and a cryoprecipitate containing both HBsAg and IgM anti-HBs. Aggregated 20-nm particles resembling intact HBsAg were also seen by negative staining electron microscopy of the serum cryoprecipitate. This patient fulfills all the criteria for a specific immune complex vasculitis caused by his immune response to a chronic HBV infection. These findings emphasize that HBV infection may be associated with small vessel vasculitis as well as polyarteritis nodosa, mixed cryoglobulinemia, and glomerulonephritis. A similar immune response to other viral infections may be expressed as palpable (Henoch-Schönlein) purpura also.  相似文献   
6.
7.
This report describes a spectrum of respiratory symptoms in workers exposed to trimellitic anhydride (TMA), a biologically reactive chemical used in the plastics industry. Fourteen workers who had worked on a unit which synthesized TMA were evaluated by clinical and immunologic methods. Respiratory syndromes induced by TMA inhalation included asthma and rhinitis of the immediate type, late onset asthma with systemic symptoms, and airway irritation. TMA was shown to couple rapidly to human serum albumin, forming an immunoreactive hapten-protein complex. The workers' immunologic reactivity to this complex could be quantitated and correlated with the three respiratory syndromes. The asthma-rhinitis syndrome was mediated by IgE antibody specific for the TMA hapten. The syndrome of late onset asthma with systemic symptoms was accompanied by elevated levels of TMA-specific IgG antibody. Rheumatoid factor in high titer was found in one worker with IgE-mediated asthma and in two workers with asthma of late onset. Lymphocyte reactivity of TMA-HSA was demonstrated in three workers representative of the three clinical syndromes. Leukocyte histamine release was demonstrated to TMA-HSA in one worker with high levels of IgE antibody specific for TMA-HSA who had severe symptoms of acute rhinitis and asthma.  相似文献   
8.
Growth of diploid cells from breast cancers   总被引:1,自引:0,他引:1  
Cell cultures were derived from normal and cancerous breast tissues and from metastases by methods that selected for relatively adherent epithelial aggregates. Karyotypic analyses of first or second passage cultures yielded predominantly normal diploid cells. Nonclonal aberrations were more common in tumor-derived than in normal cultures. Three of the cultures that originated from metastases were characterized by abnormal clones. These results support observations based on DNA content, which indicate that a considerable fraction of breast cancers are composed predominantly of diploid cells. They differ greatly from chromosomal findings in long-term cultures of tumor effusions and thus emphasize the karyotypic diversity that can be found in tumors from a single tissue of origin--the breast.  相似文献   
9.
Inhaled trimellitic anhydride (TMA) reacts with airway proteins to produce trimellityl (TM) proteins. The TM-proteins result in both systemic and local immune responses, of which various proteins present in the airway can be used for markers. Thus TM-human serum albumin (HSA), TM-IgG, and TM-IgA can be used as hapten-protein complexes for immunologic studies in sera of humans exposed to TMA by inhalation. Various immunologic assays have been established to measure antibodies against TM-proteins and have various purposes. With TM-HSA as a model antigen, total serum antibody may be measured by the ammonium sulfate technique of coprecipitation of TM-125I HSA. By solid-phase radioimmunoassays, IgE, IgG, IgA, and IgM antibodies can be measured. Lymphocyte reactivity can be measured by 3H thymidine uptake of TM-protein-stimulated lymphocytes. Biologic effects of IgE antibody can be measured by allergy skin tests and leukocyte histamine release with TM-proteins such as TM-HSA. The reaction of TMA with proteins results in alteration of those proteins that include changes in charge and physical conformation, the latter resulting in an apparent change in molecular size. These changes may relate to the observations that human antibody is not merely directed against the hapten in the hapten-human protein complex but also against new antigenic determinants formed by the TM-protein complex. Correlations have been made with certain human immunologic responses and lung disease after TMA inhalation, as follows: IgE antibody against TM-proteins correlates with TMA-induced rhinitis, conjunctivitis, and asthma; high levels of total antibody, IgG, and IgA antibody appear to correlate with the late respiratory systemic syndrome, probably a variant of hypersensitivity pneumonitis; workers exposed to TMA fumes (rather than TMA powder) have the highest levels of antibody, and this may correlate with occurrence of the hemorrhagic pneumonitis seen in this group of workers; patients with no symptoms or mild irritative symptoms have the lowest or no antibody levels. The immunopathogenetic relationships may be better understood with the further development of animal models of TMA lung disease now available.  相似文献   
10.
The calcium ionophore A23187(A23) at concentrations exceeding 1 microgram/ml has been shown to be progressively cytotoxic for human blood basophils, neutrophils, lymphocytes, and erythrocytes. Toxicity to basophils was considered to be manifested by the increasing inability of 2-deoxyglucose (2DG) to inhibit histamine release (HR) at increasing concentrations of A23. The toxicity to neutrophils and lymphocytes was demonstrated by decreased lactate production (LP) after incubation with A23 of Ficoll-Hypaque fractions greatly enriched in each respective cell type. Red cells present in dextran-sedimented leukocytes were increasingly susceptible to lysis during washing subsequent to exposure to increasing concentrations of A23. A concentration of 4 microgram A23/ml, which is cytotoxic at 37 degrees C, produced optimal and noncytotoxic HR at 22 degrees C. It was possible to reduce A23 concentrations required for optimal HR by increasing Ca++ from 0.6 to 3 mM.  相似文献   
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