Fetal myelomeningocele diagnosed in the antenatal period: Maternal-fetal characteristics and their relationship with pregnancy decision-making.

BACKGROUND: Spina bifida is the most common fetal anomaly of the central nervous system, which affects approximately 1:1000 live births in the United States. Myelomeningocele (MMC) is the most common presentation of spina bifida, representing half of these cases. Given the deformation to the spinal cord and the nerve roots, this defect may result in significant morbidity to infants and major life-long disabilities. In this study we aimed to identify maternal and fetal characteristics associated with expectant management or termination of pregnancy in the setting of antenatally diagnosed MMC. We hypothesized that the level of the defect would correlate with patient's decision to continue the pregnancy. METHODS: A retrospective cohort analysis was performed with patients who had presented to the Cleveland Clinic Fetal Care Center between 2005-2017. RESULTS: Our data showed 36% of patients with antenatal diagnosis of MMC elected for second trimester terminations versus 64% who chose to continue their pregnancy and deliver either by cesarean section or vaginal delivery. Based on ultrasound findings, there were no significant differences between these two groups. Maternal body mass index was significantly higher in those who continued pregnancies (p = 0.036). In addition, the fetal diagnostic methods chosen by patients were significantly different. Those who elected to terminate were more likely to pursue amniocentesis (p = 0.03) and less likely to opt for MRI characterization of the fetus (p = 0.007). CONCLUSION: We conclude, in the setting of fetal MMC diagnosed during pregnancy, patients often rely less on the associated ultrasonographic findings. Personal decisions likely influence the choice of other fetal diagnostic modalities. Other than BMI, we did not see an association between maternal factors and decisions regarding second trimester pregnancy termination.

Metabolism of R-beta-hydroxypentanoate and of beta-ketopentanoate in conscious dogs.

R-beta-Hydroxypentanoate and beta-ketopentanoate are homologues of physiological ketone bodies R-beta-hydroxybutyrate and acetoacetate. They derive from the oxidation in liver of the R-moiety of R,S-1,3-pentanediol, a potential nutrient. This report documents the metabolism of R-beta-hydroxypentanoate and beta-ketopentanoate in conscious dogs. Whether administered by bolus or constant infusion, the two substrates are interconverted and rapidly metabolized. When beta-ketopentanoate was infused at a rate corresponding to 75% of the dog's caloric requirement, the steady-state total plasma concentration of the two substrates was only 1.3 mM. Because the substrates are precursors of propionyl-CoA, we assayed the urinary concentrations of markers of propionic acidemia. Their accumulation was minor compared with what is observed in patients suffering from propionic acidemia. We conclude that, at least during short-term experiments, R-beta-hydroxypentanoate and beta-ketopentanoate are well metabolized in the dog without apparent intolerance to a large supply of propionyl-CoA.

The impact of formulary reservations on drug utilization: a controlled trial.

A controlled trial was conducted in two teaching hospitals (A and B), with similar case mixes to determine the impact of reservations, which were educational in nature, on the utilization of oral ciprofloxacin. Over a two-month period the health records of all the patients who received the drug were reviewed, and information on utilization and demographics of patients receiving the drug was recorded. As well, the number of admissions to the two hospitals over this period were compared. If culture and sensitivity (C & S) results were available, appropriateness was assessed in accordance with criteria for use established at site A; in the absence of C & S information, consensus by two microbiologists was used. Over the two-month period a total of 136 patients received ciprofloxacin at the two institutions. At site A, which had reservations, the number of patients who continued to receive ciprofloxacin upon admission was significantly decreased relative to site B, which did not have reservations (14% vs. 36% respectively, p = .029). As well, when assessed by total number of admissions to the institutions, the number of patients receiving ciprofloxacin at site A was less than site B (1.5% vs. 2.6% respectively, p = .003)). While the utilization was decreased at site A vs. site B, the proportion of patients with therapy deemed to be appropriate was not different between the two sites. Educationally based reservations are an effective formulary tool for optimizing drug utilization.

Assay of the concentration and 13C enrichment of acetate and acetyl-CoA by gas chromatography-mass spectrometry.

We present two techniques for determining the concentration and 13C enrichment of acetate in biological fluids. After the sample has been spiked with an internal standard of [2,2,2,2H3,1-13C]acetate, acetate is first enzymatically converted to acetyl-coenzyme A, which is chemically converted to acetylglycine. The latter is analyzed by gas chromatography-mass spectrometry, either as a methyl ester by positive chemical ionization or as a pentafluorobenzyl ester by negative chemical ionization. The mole percentage enrichment of tissue acetyl-CoA can also be assayed after conversion to acetylglycine pentafluorobenzyl ester.

Nonhomogeneous labeling of liver extra-mitochondrial acetyl-CoA. Implications for the probing of lipogenic acetyl-CoA via drug acetylation and for the production of acetate by the liver.

The labeling of liver extra-mitochondrial acetyl-CoA was investigated in isolated rat livers perfused with [2-(13)C]acetate, [1-(13)C]octanoate, or [1,2,3,4-(13)C4]docosanoate and with drugs that undergo acetylation (phenylaminobutyrate, paraaminobenzoate, and sulfamethoxazole; singly or in combination). The 13C enrichment of mitochondrial acetyl-CoA was probed by the enrichment of R-beta-hydroxybutyrate. The latter was not enriched from [1,2,3,4-(13)C4]docosanoate, thus excluding mitochondrial beta-oxidation of docosanoate. The 13C enrichment of extra-mitochondrial acetyl-CoA was probed by the enrichments of acetylated drugs and of free acetate. In most cases, the four probes yielded different enrichments. Thus, extra-mitochondrial acetyl-CoA appears nonhomogeneous. Competition between drugs alters the labeling of individual acetyl-CoA sub-pools. The labeling pattern of acetylated drugs suggests the existence of more than the two N-acetyltransferases identified so far by others. Our data question the possibility of probing the pool of lipogenic acetyl-CoA via drug acetylation.

Assay of the acetyl-CoA probe acetyl-sulfamethoxazole and of sulfamethoxazole by gas chromatography-mass spectrometry.

We present gas chromatographic-mass spectrometric assays for (i) the concentration of sulfamethoxazole and (ii) the concentration and molar percentage enrichment of acetyl-sulfamethoxazole in biological fluids. The compounds are extracted with ethyl acetate, derivatized with either diazomethane or pentafluorobenzyl bromide, and analyzed by gas chromatography-mass spectrometry. Quantitation is achieved using internal standards, [2H4]sulfamethoxazole and acetyl-[2H4]sulfamethoxazole. Limits of detection are 200 nmol for the methyl derivatives and 2 nmol for the pentafluorobenzyl derivatives. The high sensitivity of the assay with the pentafluorobenzyl derivatives allows measuring in plasma and urine (i) the pharmacokinetics of sulfamethoxazole and acetyl-sulfamethoxazole and (ii) the stable isotope enrichment of the acetyl moiety of acetyl-sulfamethoxazole. The latter is used as a probe for the noninvasive chemical biopsy of liver extramitochondrial acetyl-CoA.

Nebulized albuterol in acute childhood asthma: comparison of two doses.

Thirty-three children and adolescents from 5 to 17 years of age with moderate to severe acute asthma were given nebulized albuterol therapy in either a high (0.30 mg/kg body weight) or standard (0.15 mg/kg) dose administered at three hourly intervals in a randomized double-blind study. The high-dose hourly regimen resulted in significantly greater improvement in the forced expiratory volume in 1 second (FEV1). Furthermore, patients receiving the high dose showed a steady improvement in the FEV1 from the start to the end of the study, whereas FEV1 plateaued after the second dose in the standard-dose group. Although a rise in heart rate and a fall in serum potassium level occurred, neither of these changes nor other side effects were different in the two groups. The high-dose therapy resulted in much higher serum albuterol levels than the standard dose. There was no correlation between the drug levels and side effects or initial and subsequent FEV1. It is concluded that occasional hourly high-dose albuterol therapy should be considered for some pediatric patients with acute asthma of moderate severity, especially those who relapse between doses.

A quantitative automated immunoassay for fibrinogen/fibrin degradation products.

We describe a prototype quantitative automated assay for fibrin and fibrinogen degradation products, a particle-enhanced turbidimetric inhibition immunoassay (PETINIA) in the Du Pont aca discrete clinical analyzer. This assay involves a latex particle reagent with covalently bound fibrinogen and a polyclonal antiserum raised in rabbits against human fibrinogen. A special secondary sample-collection tube quantitatively removes fibrinogen from citrated plasma and inhibits further fibrinolysis, independent of heparin concentration. The assay range is 0-100 mg/L, in fibrinogen equivalents. The CV for the assay is less than 10% when performed with the aca. Nonclottable fibrin and fibrinogen fragments are measured by the assay, the greatest sensitivity being directed at the E domain of the fibrinogen molecule. We illustrate with case studies the potential of this assay for providing clinical information not obtainable with currently available qualitative and semi-quantitative assays.

Development and analytical performance of automated tests for antithrombin III and plasminogen on the Du Pont aca analyzer.

We describe assays for functional antithrombin III (AT III) and plasminogen in plasma with the Du Pont aca discrete clinical analyzer. Both are two-stage kinetic assays, based on synthetic substrate methodologies, and require 20-microL sample volumes. In the AT III assay the sample is incubated with excess thrombin and heparin to form the functionally inactive AT III-thrombin complex. Residual thrombin is measured through its rate of hydrolysis of a lysine thioester and is inversely related to analyte concentration. In the plasminogen assay excess streptokinase is reacted with the sample to form an enzymatically active complex. The substrate hydrolysis rate of this complex is measured, which is linearly related to the concentration of plasminogen in the sample. Reaction conditions for both assays were optimized by univariate and response surface techniques. The assay for AT III has a range of 0 to 150% of the value for normal human plasma (% NHP) with a CV of 3% at 80% NHP. The plasminogen assay is linear from 25 to 200% NHP with a CV of less than 2% at 80% NHP. No significant interferences with either method by common blood components or drugs were found.

Relationship between Vital Staining and Subculture Growth during the Senescence of Plant Tissue Cultures.

The vital staining properties of rose cultures (Rosa cv Paul's Scarlet) of increasing age were compared with their ability to be subcultured. At 4-day intervals beginning on day 14, after cell division and expansion had stopped, cells were stained separately with Evans blue, fluorescein diacetate, and phenosafranine. The degree to which parent cultures stained with each of these dyes was compared to the dry weight of their subcultures harvested after 9 and 21 days of growth.Staining with either Evans blue or fluorescein diacetate was demonstrated to be a good means of establishing when senescing cells died. However, the staining properties of aging cultures did not correlate well with their ability to be subcultured, because an increasing proportion of the living cells appeared to lose their ability to divide as senescence progressed.