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H L Sherman

Publications and source records attributed to H L Sherman.

6 recordsLinked to original sources
PubMed2000

Transpulmonary passage of Albunex as a marker of intracardiac hemodynamics and outcome in chronic congestive heart failure.

BACKGROUND: Aggressive management to reduce pulmonary artery systolic pressure (PASP) and pulmonary capillary wedge pressure (PCWP) reduces hospitalization rates and is crucial for patients awaiting transplantation but may require periodic invasive monitoring with right heart catheterization. METHODS: The purpose of this study was to define the relation of transpulmonary passage of Albunex (Mallinckrodt Medical, St Louis, Mo) to intracardiac hemodynamics and clinical outcome in patients with chronic congestive heart failure (CHF). Patients (n = 38) with chronic CHF underwent graded dobutamine infusion (baseline, 5, 10, 20 microg/kg per minute; 5-minute stages) with 5.0 mL Albunex injected intravenously at each stage. The dobutamine dose at which Albunex appeared in the left ventricle was determined. All patients had right heart catheterization to determine PASP and PCWP. RESULTS: Transpulmonary passage of Albunex at baseline or at 5 microg/kg per minute dobutamine infusion predicted PCWP <20 mm Hg with a positive predictive value of 100% and a negative predictive value of 79%. Initial appearance of Albunex in the left ventricle at a dobutamine dose of 20 microg/kg per minute or failure to appear at any dose predicted a PCWP >20 mm Hg with a positive predictive value of 100% and a negative predictive value of 94%. No patient with Albunex passage at baseline sustained a major adverse event. Major adverse events occurred in 11 of 21 patients in whom Albunex either failed to cross or crossed the pulmonary bed at a dose of 20 microg/kg per minute of dobutamine. CONCLUSION: In patients with chronic CHF, transpulmonary passage of Albunex during dobutamine infusion can be used to predict both elevated and normal intracardiac pressures and to identify a subset of patients at high risk for an adverse outcome.

Adult↗
PubMed1995

False positives in recognition memory produced by cohort activation.

Cohort theory in spoken-word recognition assumes that a cohort of word candidates consistent with incoming sensory information is activated implicitly as a spoken sound stimulus unfolds over time. Five experiments examined implications of this internal-generation-of-words mechanism. In Experiments 1 and 2, a "base" word was disqualified (the sensory information was no longer consistent with the word) either early or late in the presentation of a spoken stimulus. On a later recognition-memory test, significantly more false-positive errors occurred to base words following presentations of study items that had late, compared to early, disqualification points. Experiments 3-5 tested whether this phenomenon could be accounted for in terms of overlapping features between non-word stimuli and their base words or in terms of a post-identification processing mechanism. Experiment 3 replicated Experiments 1 and 2, and demonstrated that differences in early and late disqualification points for non-word targets, unlike word targets, were not related to false-positive recognition memory errors. The study inter-item interval in Experiment 4 was reduced to 1 s to minimize the role of post-identification processing activities, and the results for both word and non-word targets were consistent with Experiment 3. A word-association task in Experiment 5 revealed that the late non-word derivations used in this research were on the average more effective stimuli than the early non-word derivations in eliciting their base words. However, even when comparisons were restricted to item sets with early and late non-words that were equally effective in eliciting base words, false-positive recognition memory errors to target words were higher following prior presentations of their late derived non-words than following prior presentations of their early derived non-words.

Adult↗
PubMed1990

Modulation of apolipoprotein B-100 mRNA editing: effects on hepatic very low density lipoprotein assembly and intracellular apoB distribution in the rat.

We have studied the consequences of alterations to hepatic apoB mRNA editing on the biosynthesis and intracellular distribution of newly synthesized apoB variants together with their mass distribution in nascent Golgi very low density lipoproteins (VLDL). Radiolabeled liver membrane fractions were prepared from control or hypothyroid animals and separated by discontinuous sucrose gradient centrifugation. Hepatic apoB-100 synthesis in these groups accounted for 93-100% of total newly synthesized apoB species of Golgi fractions recovered from the sucrose gradients (G1 and G2). The analogous fractions isolated from the livers of hyperthyroid (treated with 3,3',5-triiodo-L-thyronine, T3) animals revealed that newly synthesized apoB-100 accounted for only 46 +/- 10% (G1) and 24 +/- 11% (G2), respectively, of total newly synthesized apoB. ApoB-100 mass in nascent Golgi VLDL from control and hypothyroid G1 fractions represented 70-78% total apoB as determined by Western blot analysis. By contrast, Golgi VLDL from hyperthyroid animals contained predominantly (greater than 78%) apoB-48 as the apoB species. Electron microscopy revealed that the morphology and size distribution of hyperthyroid G1 VLDL were similar to particles isolated from control animals. Thus, despite a profound reduction in the proportion of apoB-100 mRNA species containing an unmodified codon (CAA, B-GLN) at position 2153 in hyperthyroid animals (6 +/- 1% vs 50-61% in control and hypothyroid animals) apoB-100 biosynthesis was detectable in a defined membrane fraction isolated by discontinuous sucrose gradient centrifugation. However, no apoB-100 synthesis was detectable in liver samples prepared by Polytron disruption in Triton-containing buffers. These data suggest that effective hepatic VLDL assembly and secretion in the T3-treated rat continues despite a profound reduction in apoB-100 biosynthesis and implies that apoB-48 contains the requisite domains to direct this process, a situation analogous to that in the intestine.

Animals↗