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1.
Conall T. Morgan Brigitte Mueller Varsha Thakur Vitor Guerra Callaghan Jull Luc Mertens Mark Friedberg Fraser Golding Mike Seed Steven E.S. Miner Edgar T. Jaeggi Cedric Manlhiot Lynne E. Nield 《The Canadian journal of cardiology》2019,35(4):453-461
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.
End-tidal Carbon Dioxide Monitoring during Procedural Sedation 总被引:2,自引:0,他引:2
James R. Miner MD William Heegaard MD MPH David Plummer MD 《Academic emergency medicine》2002,9(4):275-280
OBJECTIVE: To prospectively determine whether end-tidal carbon dioxide (ETCO2) monitors can detect respiratory depression (RD) and the level of sedation in emergency department (ED) patients undergoing procedural sedation (PS). METHODS: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS. Patients were monitored for vital signs, depth of sedation per the physician by the Observer's Assessment of Alertness/Sedation scale (OAA/S), pulse oximetry, and nasal-sample ETCO2 during PS. Respiratory depression was defined as an oxygen saturation <90%, an ETCO2 >50 mm Hg, or an absent ETCO2 waveform at any time during the procedure. The physician also determined whether protective airway reflexes were lost during the procedure and assisted ventilation was required, or whether there were any other complications. Rates of RD were compared with the physician assessment of airway loss and between agents using chi-square statistics. Spearman's rho analysis was used to determine whether there was a correlation between ETCO2 and the OAA/S score. RESULTS: Seventy-four patients were enrolled in the study. Forty (54.1%) received methohexital, 21 (28.4%) received propofol, ten (13.5%) received fentanyl and midazolam, and three (4.1%) received etomidate. Respiratory depression was seen in 33 (44.6%) patients, including 47.5% of patients receiving methohexital, 19% receiving propofol (p = 0.008), 80% receiving fentanyl and midazolam, and 66.6% receiving etomidate. No correlation between OAA/S and ETCO2 was detected. Eleven (14.9%) patients required assisted ventilation at some point during the procedure, all of whom met the criteria for RD. Pulse oximetry detected 11 of the 33 patients with RD. Post-hoc analysis revealed that all patients with RD had an ETCO2 >50 mm Hg, an absent waveform, or an absolute change from baseline in ETCO2 >10 mm Hg. CONCLUSIONS: There was no correlation between ETCO2 and the OAA/S score. Using the criteria of an ETCO2 >50 mm Hg, an absolute change >10 mm Hg, or an absent waveform may detect subclinical RD not detected by pulse oximetry alone. The ETCO2 may add to the safety of PS by quickly detecting hypoventilation during PS in the ED. 相似文献
3.
Proteins were extracted from corneocytes of skin of 2-day-old rats and fractionated by gel filtration and cation exchange column chromatography. The different protein fractions were tested for direct inactivation of herpes simplex virus infectivity as determined by reduction of plaque formation. The most effective protein fractions against herpes simplex virus were a neutral pH buffer soluble and mol. wts. ranging from 20 K to 30 K. Amino acid composition of the proteins were virtually identical to epidermal histidine-rich proteins. The activity was significantly (P less than 0.001) stronger against type-2 than type-1. The activity was most stable at pH 7.2 and the rate of inhibition increased in a time-dependent manner up to 4 h. The 50% effective dose was estimated as 1.1 micrograms protein/ml. 相似文献
4.
Does increased intracranial pressure in patients with pseudotumour cerebri PTC result in cognitive impairments The results of previous investigations have not clarified this question It may be that there is a subgroup within those diagnosed with PTC that does experience cognitive decline with increased intracranial pressure However elevated intracranial pressure headache and emotional distress also can contribute to reduced cognitive performance and increased self monitoring As a result of the lack of clarity regarding the impact of PTC on cognition clinicians are left with no empirically derived practice guidelines A case study demonstrates subjective complaints of concentration and memory deficits in a depressed patient with PTC whose neuropsychological stores except Seashore Rhythm Test were in the normal range 相似文献
5.
6.
Janine M Prince Teresa C M Klinowska Emma Marshman Emma T Lowe Ulrike Mayer Jeff Miner Daniel Aberdam Dietmar Vestweber Barry Gusterson Charles H Streuli 《Developmental dynamics》2002,223(4):497-516
Epithelial cell survival is dependent on extracellular signals provided by both soluble factors and by adhesion. In the mammary gland, extensive apoptosis of epithelial cells occurs rapidly when lactation ceases, but the mechanism of apoptosis induction is not known. In tissue culture, mammary epithelial cells require laminin as a survival ligand and specific beta1 integrins are necessary to suppress apoptosis. To explore the possibility that dynamic changes in cell-matrix interactions contribute to the onset of apoptosis during mammary involution in vivo, a detailed immunohistochemical analysis of the expression of integrin subunits and their extracellular matrix ligands during mouse mammary gland development has been performed. The kinetics of apoptosis were determined by using tissue samples obtained from virgin, pregnant, lactating, and involuting gland. The maximal elevation of apoptosis occurred within 24 hr of weaning as determined by histologic analysis and caspase-3 staining. A wide variety of laminin subunits, together with nidogen-1 and -2, and perlecan were identified within the basement membrane region of epithelial ducts, lobules, and alveoli in both human and mouse mammary gland. However, no change in the distribution of any of the basement membrane proteins or their cognate integrin receptors was observed during the transition from lactation to apoptosis. Instead, we discovered that altered ligand-binding conformation of the beta1 integrin to a nonbinding state coincided with the immediate onset of mammary apoptosis. This finding may provide a novel dynamic mechanism for inhibiting the transduction of extracellular matrix survival signals, thereby contributing to the onset of apoptosis in a developmental context in vivo. 相似文献
7.
K M Miner C L Manyak E Williams J Jackson M Jewell M T Gammon C Ehrenfreund E Hayes L T Callahan rd H Zweerink et al. 《Infection and immunity》1986,52(1):56-62
Results show that various inbred strains of mice can be segregated into two distinct groups, based on their capacity to allow a number of nontuberculous mycobacterial infections to grow in target organs following experimental intravenous infection. The first group, which allowed these infections to grow progressively, was thus designated as naturally susceptible to these infections; in contrast, those strains which were able to exert detectable bacteriostasis were designated as naturally resistant. It was then found that segregation of mouse strains based on this distinction also mirrored the capacity of these animals to generate acquired immunity to the mycobacterial infections. For example, Mycobacterium simiae grew progressively in susceptible C57BL/6 mice, subsequently triggering acquired mechanisms of immunity, whereas no evidence for acquired immunity could be found in resistant A/Tru mice infected with this organism. The possibility that acquired immunity could not be expressed in the latter strain as a result of a defect in macrophage activation was excluded. Moreover, it was found that the trait of resistance to these infections could be transferred by bone marrow cells into radiation chimeras, thus indicating that this trait was expressed by the progeny of hemopoietic precursor cells. Subsequent backcross analysis to determine the mode of inheritance of the trait of resistance to these mycobacterial infections revealed data that were consistent with the hypothesis that this resistance is controlled by more than one gene. Statistical analysis of the data by the maximum likelihood method suggested polygenic control, although in some cases the probability values suggested control by a major gene, influenced by modifier genes. These findings suggest that the previous hypothesis that the growth of mycobacterial infections in inbred strains of mice is controlled by a single gene should be reevaluated. 相似文献
8.
Simultaneous detection of antibodies to cytomegalovirus and herpes simplex virus by using flow cytometry and a microsphere-based fluorescence immunoassay. 总被引:2,自引:0,他引:2 下载免费PDF全文
A sensitive assay for the simultaneous detection of anti-cytomegalovirus and anti-herpes simplex virus antibodies was developed. Two different sizes of polystyrene microspheres were coated with purified viral antigens. Human antiviral antibodies were detected with a biotin-streptavidin amplification procedure with phycoerythrin as the fluorescent label. Microsphere-associated fluorescence was quantitated with a flow cytometer. Sixteen percent of samples initially scored as seronegative for cytomegalovirus and 35% of samples initially scored as seronegative for herpes simplex virus by conventional assays were clearly found positive by the microsphere technique. This flow cytometric assay can simultaneously detect several specific antibodies at levels which are below the sensitivity of standard assays. The dynamic range of this assay is at least sixfold greater than that of enzyme immunoassays. This technique is amenable to numerous serologic assays and could greatly expand the clinical laboratory applications of flow cytometry. 相似文献
9.
10.
OBJECTIVE: To investigate the influence of relationships on psychosocial status in patients with Stage III and IV brain tumours. PATIENTS AND METHODS: Thirty-three outpatients at a university medical centre were referred to the study by their treating physician prior to the initiation of aggressive chemotherapy. All subjects underwent a comprehensive psychosocial assessment. RESULTS: Depressive and anxious complaints were common, but not related to gender. Single/divorced status suggested greater vulnerability to anxiety as 88% of singles and only 48% of patients with partners reported clinical levels of anxiety. Single patients' anxiety was related to inactivity (r = 0.78, p < 0.05) and fears of financial difficulties (r = 0.72, p < 0.05). State and trait anxiety related differently to married patients' complaints. Married patients more frequently reported clinical levels of depressive symptoms (44% partnered vs 28% singles). Depression among married patients was predicted by problems with sex, finances, marital difficulties, and inactivity [R2 = 0.803; F = 20.420, df(4,20), p < 0.0001)]. Problems with relationships were disassociated from problems with sex. Married patients' problematic relationships were predicted by overprotection, inactivity, concerns of bodily deterioration, depression, and anxiety [R2 = 0.775, F = 13.060, df(5, 19) < 0.0001]. CONCLUSIONS: Married neuro-oncology patients may experience depressive symptoms arising from the marriage, but appear to be buffered from anxiety when compared with single/divorced patients. The prevalence of anxiety among single patients suggests modifications of interventions by relationship status. 相似文献