Development, women-centricity and psychometric properties of maternity patient-reported outcome measures (PROMs): A systematic review

BACKGROUND

Measuring maternity care outcomes based on what women value is critical to promoting woman-centred maternity care. Patient-reported outcome measures (PROMs) are instruments that enable service users to assess healthcare service and system performance.

AIM

To identify and critically appraise the risk of bias, woman-centricity (content validity) and psychometric properties of maternity PROMs published in the scientific literature.

METHODS

MEDLINE, CINAHL Plus, PsycINFO and Embase were systematically searched for relevant records between 01/01/2010 and 07/10/2021. Included articles underwent risk of bias, content validity and psychometric properties assessments in line with COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidance. PROM results were summarised according to language subgroups and an overall recommendation for use was determined.

FINDINGS

Forty-four studies reported on the development and psychometric evaluation of 9 maternity PROMs, grouped into 32 language subgroups. Risk of bias assessments for the PROM development and content validity showed inadequate or doubtful methodological quality. Internal consistency reliability, hypothesis testing (for construct validity), structural validity and test-retest reliability varied markedly in sufficiency and evidence quality. No PROMs received a level 'A' recommendation, required for real-world use.

CONCLUSION

Maternity PROMs identified in this systematic review had poor quality evidence for their measurement properties and lacked sufficient content validity, indicating a lack of woman-centricity in instrument development. Future research should prioritise women's voices in deciding what is relevant, comprehensive and comprehensible to measure, as this will impact overall validity and reliability and facilitate real-world use.

Universal DNA methylation age across mammalian tissues

Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.

Association between nonalcoholic fatty liver disease and carotid intima-media thickness

Background

Many non-invasive methods have been studied for assessing the severity of fatty liver disease and carotid intima-media thickness (CIMT). However, the correlation between hepatic steatosis and CIMT has not been fully studied, either globally or in Vietnam. This study investigated the association between nonalcoholic fatty liver disease (NAFLD) and CIMT.

Methods

A cross-sectional study was performed on 125 patients at the Cardiology Department, the Emergency Interventional Cardiology Department, and the Internal Cardiology Clinic of Thong Nhat Hospital.

Results

Among the 125 patients in our study population, NAFLD was diagnosed in 56%, and the mean CIMT was 0.89 ± 0.48 mm. Normal CIMT was measured in 21% of patients, whereas 79% had an elevated CIMT. The NAFLD rates were significantly different between patients with normal and increased CIMT, at 26.9% and 69.6%, respectively (p = 0.001).

Conclusions

Our study revealed a strong association between NAFLD and CIMT. NAFLD is currently considered a feature of metabolic syndrome, and an increase in the prevalence of NAFLD might result in an increase in the incidence of cardiovascular disease.

Correlation between nonalcoholic fatty liver disease and coronary atherosclerosis

BACKGROUND

Various non-invasive methods have been studied for assessing the severity of fatty liver disease and coronary atherosclero-sis. However, the correlation between hepatic steatosis and coronary atherosclerosis has not been fully studied, either globally or specifically in Vietnam. This study investigated the association between nonalcoholic fatty liver disease (NAFLD) and coronary atherosclerosis using coronary computed tomography angiography (CCTA).

METHODS

An analytical cross-sectional study was performed, including 223 patients treated by the Cardiology Department, the Emergency Interventional Cardiology Departments, and the Internal Cardiology Clinic of Thong Nhat Hospital.

RESULTS

In our cohort of 223 patients, the NAFLD was detected in 66% of the population, the mean coronary artery stenosis (CAS) was 44.54% ± 20.23%, and the mean coronary artery calcium score (CACS) was 3569.05 ± 425.99, as assessed using the Agatston method. The proportion of patients with significant atherosclerotic plaque (CAS 50%) >was 32%, whereas the remaining 68% had insignificant stenosis. Among our study population, 16% had no coronary artery calcification, 38% had mild calcification, and 46% had moderate to severe calcification. In the group of NAFLD patients, 33.3% had significant atherosclerotic plaque, which was not significantly different from the rate in individuals without NAFLD (p = 0.51). Mild coronary artery calcification was detected in 37.4% of NAFLD patients, and moderate to severe calcification was detected in 48.3% (p = 0.45).

CONCLUSIONS

NAFLD was not found to be strongly associated with coronary atherosclerosis in this study. More studies with larger sample sizes remain necessary to verify whether any correlation exists.

Latitudinal variation in top-down and bottom-up control of a salt marsh food web

The shrub Iva frutescens, which occupies the terrestrial border of U.S. Atlantic Coast salt marshes, supports a food web that varies strongly across latitude. We tested whether latitudinal variation in plant quality (higher at high latitudes), consumption by omnivores (a crab, present only at low latitudes), consumption by mesopredators (ladybugs, present at all latitudes), or the life history stage of an herbivorous beetle could explain continental-scale field patterns of herbivore density. In a mesocosm experiment, crabs exerted strong top-down control on herbivorous beetles, ladybugs exerted strong top-down control on aphids, and both predators benefited plants through trophic cascades. Latitude of plant origin had no effect on consumers. Herbivorous beetle density was greater if mesocosms were stocked with beetle adults rather than larvae, and aphid densities were reduced in the "adult beetle" treatment. Treatment combinations representing high and low latitudes produced patterns of herbivore density similar to those in the field. We conclude that latitudinal variation in plant quality is less important than latitudinal variation in top consumers and competition in mediating food web structure. Climate may also play a strong role in structuring high-latitude salt marshes by limiting the number of herbivore generations per growing season and causing high overwintering mortality.

Does combined multichannel intraluminal esophageal impedance and manometry predict postoperative dysphagia after laparoscopic Nissen fundoplication?

Laparoscopic Nissen fundoplication (LNF) is an effective treatment for gastroesophageal reflux disease; however, some patients develop dysphagia postoperatively. Manometry is used to evaluate disorders of peristalsis, but has not been proven useful to identify which patients may be at risk for postoperative dysphagia. Multichannel intraluminal impedance (MII) evaluates the effective clearance of a swallowed bolus through the esophagus. We hypothesized that MII combined with manometry may detect those patients most at risk of developing dysphagia after LNF. Between March 2003 and January 2007, 74 patients who agreed to participate in this study were prospectively enrolled. All patients completed a preoperative symptom questionnaire, MII/manometry, and 24-h pH monitoring. All patients underwent LNF. Symptom questionnaires were administered postoperatively at a median of 18 months (range: 6-46 months), and we defined dysphagia (both preoperatively and postoperatively) as occurring more than once a month with a severity >or=4 (0-10 Symptom Severity Index). Thirty-two patients (43%) reported preoperative dysphagia, but there was no significant difference in pH monitoring, lower esophageal sphincter pressure/relaxation, peristalsis, liquid or viscous bolus transit (MII), or bolus transit time (MII) between patients with and without preoperative dysphagia. In those patients reporting preoperative dysphagia, the severity of dysphagia improved significantly from 6.8 +/- 2 to 2.6 +/- 3.4 (P < 0.001) after LNF. Thirteen (17%) patients reported dysphagia postoperatively, 10 of whom (75%) reported some degree of preoperative dysphagia. The presence of postoperative dysphagia was significantly more common in patients with preoperative dysphagia (P= 0.01). Patients with postoperative dysphagia had similar lower esophageal sphincter pressure and relaxation, peristalsis, and esophageal clearance to those without dysphagia. Neither MII nor manometry predicts dysphagia in patients with gastroesophageal reflux disease or its occurrence after LNF. The presence of dysphagia preoperatively is the only predictor of dysphagia after LNF.

A diagnosis support system for capsule endoscopy

The diagnostic time required for a full, 8-hour video capsule endoscopy is usually between 45 and 120 min. The aim of this work is to evaluate the diagnostic time required when applying a method that adaptively controlls the image display rate. The advantage of the method is that the sequence can be played at high speed in stable smooth sequences to save time and then decreased at sequences where there are sudden rough changes, in order to assess suspicious findings detail. In this paper, this method is examined under real conditions: 10 sequences were independently evaluated by 4 medical doctors. The methods of evaluation include: 1) the time required for reading a sequence, 2) the percentage of abnormal regions accurately found, and 3) the manipulations of the evaluating physicians. The results indicate that the proposed method reduces diagnostic time to around 10 +/- 1.5% length of the sequence and is of valuable assistance to medical doctors.

On the role of the starved codon and the takeoff site in ribosome bypassing in Escherichia coli

Translating ribosomes can skip over stretches of messenger RNA and resume protein chain elongation after a "bypassed" region. We have previously shown that limitation for isoleucyl-tRNA can initiate a ribosome bypass when an AUA codon is in the ribosomal A-site. We have now generalized this effect to other "hungry" codons calling for four different limiting aminoacyl-tRNA species, suggesting that a pause at any A-site will have this effect. We have assessed bypassing in a large family of reporters with nearly every different triplet in the "takeoff site", i.e. the P-site on the 5' side of the hungry codon, and an identical "landing site" codon 16 nucleotides downstream. The different takeoff sites vary over a factor of 50 in bypassing proficiency. At least part of this variation appears to reflect stability of the codon Colon, two colons anticodon interaction at the takeoff site, as indicated by the following: (a) the bypassing proficiency of different tRNAs shows a rough correlation with the frequency of A Colon, two colons U as opposed to G Colon, two colons C pairs in the codon Colon, two colons anticodon association; (b) specific tRNAs bypass more frequently from codons ending in U than from their synonym ending in C; (c) an arginine tRNA with Inosine in the wobble position which reads CGU, CGC, and CGA bypasses much more frequently from the last codon than the first two synonyms.

Recombinant prostate specific antigen inhibits angiogenesis in vitro and in vivo

BACKGROUND

Prostate specific antigen (PSA) is a kallikrein family member with serine protease activity commonly used as a diagnostic marker for prostate cancer. We recently described anti-angiogenic properties of PSA [Fortier et al.: JNCI 91:1635-1640].

METHODS

Two forms of PSA were cloned and expressed in Pichia pastoris: one, an intact PSA with an N-terminus of IVGGVS em leader; the second, an N-1 PSA variant. The recombinant proteins were tested for serine protease activity and for anti-angiogenic activity in vitro and in vivo.

RESULTS

The rate of substrate hydrolysis by the intact recombinant PSA was similar to that of PSA isolated and purified from human seminal plasma. In contrast, the N-1 PSA variant lacked serine protease activity. In an endothelial cell migration assay, the concentration that resulted in 50% inhibition (IC(50)) was: 0.5 microM for native PSA, 0.5 microM for intact recombinant protein, and 0.1 microM for the N-1 variant PSA. Both the intact recombinant and the N-1 recombinant PSA inhibited angiogenesis in vivo.

CONCLUSIONS

Purified recombinant PSA inhibits angiogenesis, proving the concept that PSA is an anti-angiogenic, and serine protease activity, as determined by synthetic substrate hydrolysis, is distinct from the anti-angiogenic properties of PSA.

Diagnosis of malignant granular cell tumor by fine needle aspiration cytology:

BACKGROUND

Malignant granular cell tumors (GCT) are the rarest of all sarcomas, and the histologic differentiation from their benign counterpart may be extremely difficult or impossible unless metastatic disease is demonstrated. To our knowledge, this is the first report of a malignant GCT diagnosed by fine needle aspiration (FNA) cytology.

CASE

A 70-year-old, Caucasian female presented with a progressively enlarging left supraclavicular mass. FNA of the mass revealed a metastatic tumor cytologically consistent with GCT. With this diagnosis, a search for other metastatic sites was initiated. Computed tomography (CT) scan revealed several tumor nodules in the lungs and liver. CT-guided FNA and tru-cut needle biopsy of a liver mass confirmed the diagnosis of metastatic GCT. In searching for a primary site, the patient revealed a clinical history of having had a tumor removed from her back two months before; it was reported to be an atypical GCT. Comparison of the three tumors revealed similar histologic, cytologic and immunohistochemical features.

CONCLUSION

Evidence of mild to moderate cytologic atypia; increased mitotic activity; locally aggressive growth; increased proliferative activity as demonstrated by immunohistochemical evaluation of proliferation markers; and DNA ploidy analysis, as reported for this case, may be helpful in predicting malignant behavior of GCTs.

Reduced pulmonary function and its associations in type 2 diabetes: the Fremantle Diabetes Study

To determine whether diabetes is associated with reduced lung function, we studied 421 Anglo-Celt/European subjects, representing 20.5% of all patients with type 2 diabetes identified in an urban Australian catchment area of 120097 people. In addition to collection of detailed demographic and diabetes-specific data, spirometry was performed and forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), vital capacity (VC) and peak expiratory flow (PEF) measured. When expressed as a percentage of those predicted (%pred) for age, sex and height, the means of all spirometric measures were reduced by > or =9.5%. After controlling for smoking, age and gender in a linear regression model, HbA(1c) was not associated with any measure of lung function (P>0.13) but diabetes duration was significantly associated with FEV1(%pred) and PEF(%pred) (P< or =0.04) and had borderline associations with FVC(%pred) and VC(%pred) (P< or =0.064). In separate analyses controlling for smoking alone, age, body mass index (BMI), coronary heart disease (CHD) and retinopathy were independently and inversely associated with FVC(%pred), FEV1(%pred) and VC(%pred) (P<0.05). In sub-group analyses, these three spirometric measures were associated with BMI, CHD and diabetes duration in males, and age and BMI in females. Pulmonary function is reduced in type 2 diabetes. Diabetes duration seems a more important influence than glycaemic control, but obesity and vascular disease may also contribute.

The influence of global discourse on lexical ambiguity resolution

The influence of global discourse on the resolution of lexical ambiguity was examined in a series of naming experiments. Two-sentence passages were constructed to bias either the dominant or the subordinate meaning of a homonym that was embedded in a locally ambiguous sentence. The results provided evidence for the immediate (0-msec interstimulus interval) resolution of lexical ambiguity and were subsequently replicated in Experiment 2, in which an 80-msec stimulus onset asynchrony exposure duration was employed for the homonyms. Strong dominant and subordinate biased discourse contexts activated only the contextually appropriate sense of a homonym. In Experiment 3, each sentence of the discourse was presented in isolation. The pattern of activation obtained in Experiments 1 and 2 was found to be contingent on the integration of the two sentences to construct an overall global discourse representation of the text. The results support a context-sensitive model of lexical ambiguity resolution.

Strength of discourse context as a determinant of the subordinate bias effect

Two experiments examined the influence of strength of discourse bias on lexical ambiguity resolution. Short passages were constructed to bias polarized ambiguous words (homonymous) strongly or weakly toward the dominant or subordinate meanings. Using a self-paced reading task in Experiment 1, it was demonstrated that in strongly biased discourse, reading times for homonyms in dominant discourse did not differ from those in subordinate discourse. However, when the discourse was weakly biased, homonyms were read faster in dominant discourse than in subordinate discourse. Experiment 2 combined the reading paradigm with a naming task in order to provide an assessment of specific word-meaning activation. Reading times on ambiguous words replicated the results of Experiment 1. In addition, naming latencies for probe words revealed that only the contextually appropriate sense of a homonym was activated in strongly biased discourse. In contrast, both contextually appropriate and inappropriate senses were activated following a weakly biased subordinate discourse, whereas only the dominant sense was activated following weakly biased dominant discourse. The results demonstrate (1) an immediate influence of prior discourse information on lexical processing; and (2) that the strength of discourse constraints can play a governing role in lexical ambiguity resolution. The results were interpreted within the framework of a context-sensitive model of lexical ambiguity resolution.

Strength of context does modulate the subordinate bias effect: a reply to Binder and Rayner

Using a self-paced reading task, Kellas, Martin, Yehling, Herman, and Vu (1995) demonstrated that strength of context can modulate the effects of meaning frequency. Binder and Rayner (1998) initially replicated the results, using eye-tracking methodology. On further examination of the stimuli, Binder and Rayner eliminated 43% of the stimulus set and found that context strength failed to modulate meaning frequency. Binder and Rayner's initial replication of Kellas et al. and the convergence of results between their two main experiments established the validity of self-paced reading as a measure of on-line reading, when compared with eye-tracking methodology. However, their central conclusion, that context strength cannot modulate the subordinate bias effect, is open to question. In this commentary, we examine the criteria adopted to exclude items from our homonym set and discuss the issue of local versus published norms. We also discuss the issue of context strength, as related to the specific rating procedures employed. Finally, we conclude that strong context can, in fact, eliminate the subordinate bias effect and that the context-sensitive model can more fully account for the available data on lexical ambiguity resolution.

Comparative performance of the RapID Yeast Plus System and the API 20C AUX Clinical Yeast System

The performance of the RapID Yeast Plus System (Innovative Diagnostic Systems, Norcross, Ga.), a 4-h micropanel using single-substrate enzymatic test reactions, was compared with that of the API 20C AUX Clinical Yeast System (bioMerieux Vitek, Hazelwood, Mo.), a 48- to 72-h carbohydrate assimilation panel. Two hundred twenty-five yeasts, yeast-like fungi, and algae, comprising 28 species and including 30 isolates of Cryptococcus neoformans, an important pathogen not tested in appreciable numbers in other comparisons, were tested by both methods. On initial testing, 196 (87.1%) and 215 (95.6%) isolates were correctly identified by the RapID and API systems, respectively. Upon repeat testing, the number of correctly identified isolates increased to 220 (97.8%) for the RapID system and 223 (99.1%) for the API system. Reducing the turbidity of the test inoculum to that of a no. 3 McFarland turbidity standard, which is below that recommended by the manufacturer, resulted in the correct identification of most of the isolates initially misidentified by the RapID system, including 10 of 30 C. neoformans isolates. Concordance between the RapID and API results after repeat testing was 97.3%.

Plasma acylation stimulating protein, adipsin and lipids in non-obese and obese populations

BACKGROUND

Acylation stimulating protein (ASP) is a potent stimulator of TG synthesis in human adipocytes.

DESIGN

In the present study, we have analysed plasma ASP and adipsin levels and their relationships to plasma lipids in non-obese and obese groups.

RESULTS

The results show that the frequency distribution of ASP is skewed but that of adipsin is normal in both groups. In the non-obese population, the mean levels of plasma ASP and adipsin were 20.2 nmol L-1 (median) and 66.6 +/- 19 nmol L-1 (mean) respectively. No difference was observed between men and women for each of the parameters. In the obese population, the median plasma ASP was increased by 246% (69.9 nmol L-1) and adipsin by 31% (87.0 +/- 22.7 nmol L-1) above that of the control group. Although the levels for men and women were not statistically different for adipsin, the median ASP plasma concentration was 1.9-fold higher in obese women than in obese men (71.8 nmol L-1 vs. 37.6 nmol L-1, P < 0.05). Best subset regression analysis provided a model with variables that best predict plasma ASP [r2 = 0.160, P < 0.008 for body mass index (BMI), P < 0.05 for triacylglycerol (TG), P < 0.03 for free fatty acid (FFA)] and plasma adipsin (r2 = 0.057, P < 0.017 for BMI) in a non-obese population. In obese subjects, the model was different for plasma ASP (P = NS for any of the variables) and plasma adipsin (r2 = 0.356, P < 0.008 for FFA, P < 0.0002 for BMI, P < 0.02 for age). There was no correlation between ASP and adipsin in either the non-obese or the obese group.

CONCLUSION

The present data suggest involvement of the ASP/adipsin pathway in the pathogenesis of obesity.

Cloning and characterization of a cDNA encoding a novel subtype of rat thyrotropin-releasing hormone receptor

A cDNA encoding a thyrotropin-releasing hormone (TRH) receptor expressed in the pituitary was previously cloned (De La Pena, P., Delgado, L. M., Del Camino, D., and Barros, F. (1992) Biochem. J. 284, 891-899; De La Pena, P., Delgado, L. M., Del Camino, D., and Barros, F. (1992) J. Biol. Chem. 267, 25703-25708; Duthie, S. M., Taylor, P. L., Anderson, J., Cook, J., and Eidne, K. A. (1993) Mol. Cell Endocrinol. 95, R11-R15). We now describe the isolation of a rat cDNA encoding a novel subtype of TRH receptor (termed TRHR2) displaying an overall homology of 50% to the pituitary TRH receptor. Introduction of TRHR2 cDNA in HEK-293 cells resulted in expression of high affinity TRH binding with a different pharmacological profile than the pituitary TRH receptor. De novo expressed receptors were functional and resulted in stimulation of calcium transient as assessed by fluorometric imaging plate reader analysis. The message for TRHR2 was exclusive to central nervous system tissues as judged by Northern blot analysis. Studies of the expression of TRHR-2 message by in situ hybridization revealed a pattern of expression remarkably distinct (present in spinothalamic tract, spinal cord dorsal horn) from that of the pituitary TRH receptor (present in hypothalamus, and ventral horn of the spinal cord, anterior pituitary). Therefore, we have identified a novel, pharmacologically distinct receptor for thyrotropin-releasing hormone that appears to be more restricted to the central nervous system particularly to the sensory neurons of spinothalamic tract and spinal cord dorsal horn, which may account for the sensory antinociceptive actions of TRH.

Sources of sentence constraint on lexical ambiguity resolution

Results from a series of naming experiments demonstrated that major lexical categories of simple sentences can provide sources of constraint on the interpretation of ambiguous words (homonyms). Manipulation of verb (Experiment 1) or subject noun (Experiment 2) specificity produced contexts that were empirically rated as being strongly biased or ambiguous. Priming was demonstrated for target words related to both senses of a homonym following ambiguous sentences, but only contextually appropriate target words were primed following strongly biased dominant or subordinate sentences. Experiment 3 showed an increase in the magnitude of priming when multiple constraints on activation converged. Experiments 4 and 5 eliminated combinatorial intralexical priming as an alternative explanation. Instead, it was demonstrated that each constraint was influential only insofar as it contributed to the overall semantic representation of the sentence. When the multiple sources of constraint were retained but the sentence-level representation was changed (Experiment 4) or eliminated (Experiment 5), the results of Experiments 1, 2, and 3 and were not replicated. Experiment 6 examined the issue of homonym exposure duration by using an 80-msec stimulus onset asynchrony. The results replicated the previous experiments. The overall evidence indicates that a sentence context can be made strongly and immediately constraining by the inclusion of specific fillers for salient lexical categories. The results are discussed within a constraint-based, context-sensitive model of lexical ambiguity resolution.

The superoxide synthases of rose cells . Comparison Of assays

In an effort to identify the enzymatic mechanism responsible for the synthesis of reactive oxygen species produced during the hypersensitive response, preparations of rose (Rosa damascena) cell plasma membranes, partially solubilized plasma membrane protein, and cytosol were assayed for the NADH- and NADPH-dependent synthesis of superoxide using assays for the reduction of cytochrome c (Cyt c), assays for the reduction of nitroblue tetrazolium, and assays for the chemiluminescence of N,N'-dimethyl-9,9'-biacridium dinitrate (lucigenin). Each assay ascribed the highest activity to a different preparation: the Cyt c assay to cytosol, the nitroblue tetrazolium assay to plasma membrane, and the lucigenin assay to the partially solubilized plasma membrane protein (with NADH). This suggests that no two assays measure the same set of enzymes and that none of the assays is suitable for comparisons of superoxide synthesis among different cell fractions. With the plasma membrane preparation, the presence of large amounts of superoxide-dismutase-insensitive Cyt c reductase confounded attempts to use Cyt c to measure superoxide synthesis. With the partially solubilized membrane protein, direct reduction of lucigenin probably contributed to the chemiluminescence. Superoxide synthesis detected with lucigenin should be confirmed by superoxide-dismutase-sensitive Cyt c reduction.

The role of interleukin-2, interleukin-12, and dendritic cells in cancer therapy

PURPOSE

Recombinant interleukin-2 (rIL-2) administration can mediate regression of solid tumors in patients with melanoma and renal cell carcinoma. A better understanding of the mechanisms of rIL-2-mediated antitumor effects has led to the investigation of novel immunotherapeutic approaches. Two approaches that appear promising include administration of antigen-pulsed dendritic cells (DC) and administration of DC or genetically engineered fibroblasts expressing human interleukin-12 (IL-12). The rationale for these immunotherapeutic approaches and preliminary clinical studies are presented.

PATIENTS AND METHODS

We have conducted a pilot study to evaluate the feasibility of treating melanoma patients with peptide-pulsed DC. Six melanoma patients received 1 to 3 x 10(6) DC pulsed with synthetic melanoma antigenic peptides. The peptide-pulsed DC were infused weekly for 4 weeks. We have also treated 32 patients in a phase I/II trial with IL-12-producing fibroblasts. Patients received escalating doses of cells weekly for 4 weeks, which produced quantities of IL-12 ranging from 10 ng to 9 micrograms/24 hours.

RESULTS

Infusion of melanoma peptide-pulsed DC produced a complete response in one patient, and significant T-cell and DC infiltration of melanoma lesions was observed. Lesional and regional responses have been observed in patients with melanoma, head and neck carcinoma, and breast cancer who received intralesional injections of IL-12-producing fibroblasts. Phase II studies of this approach are planned and will be initiated in the next few months.

CONCLUSIONS

These studies confirm the feasibility of these novel immunotherapeutic approaches and demonstrate their potential antitumor activity. These approaches may be effective in patients with metastatic melanoma and other solid tumors, and they may ultimately be used to improve the efficacy of rIL-2-based immunotherapy.

Characterization and modulation of LP(a) in human hepatoma HEPG2 cells

HepG2 cells have been widely used to study factors which affect the secretion of apoB100 lipoprotein particles. The objectives of this study were to determine if Lp(a) particles were present in conditioned medium from HepG2 cells and if so, was this accumulation affected by factors which alter apoB100 lipoprotein metabolism. The data demonstrate that Lp(a) accumulated in the medium in a time dependent manner over a 48 h incubation period. Ultracentrifugation fractionation and Western blot analysis demonstrated that lipoprotein particles containing apo(a) in complex with apoB100 were present at a density consistent with human plasma Lp(a). Incubation of the HepG2 cells with LDL or VLDL caused increases in Lp(a) accumulation in the medium (+33% +/- 14%, P NS and 56% +/- 21%, P < 0.05, respectively). In contrast, apo(a) mRNA decreased (-17% +/- 3%, P < 0.01 for both LDL and VLDL incubation). Increasing concentrations of amino acids in the medium resulted in progressively less Lp(a) and apoB100 in the medium, the effect being greater on apoB100. ApoB100 mRNA levels decreased with incubation of HepG2 cells with amino acids (-22% +/- 10%, P < 0.06) whereas apo(a) mRNA levels increased significantly (+47% +/- 14%, P < 0.005). Taken together, our data show that HepG2 cells express mRNA for apo(a), and accumulate Lp(a) in the medium. The close correlation of medium Lp(a) levels with medium apoB100 levels, and not with apo(a) mRNA levels, suggests that medium Lp(a) accumulation may be a function of lipoprotein synthesis and secretion and is consistent with extracellular assembly of Lp(a) lipoprotein particles.

A proposal for minimum detectable compartment in MIRD dosimetry modelling

The accuracy of radiation dose estimates from radiopharmaceutical administrations has recently become more important for three main reasons: (i) clinical providers are demanding more information on diagnostic procedures; (ii) regulatory groups are scrutinizing dosimetry for research subjects; and (iii) accurate organ doses are crucial in therapeutic administrations. These dose estimates are a sensitive function of the residence times. Because most clinical data acquisition protocols are limited to the first 24 h after dose administration, the area under the remainder of the time-activity curve (TAC) must be estimated. Estimation methods range from assuming physical decay only (overly conservative) to extrapolating end point physiological kinetics (overly liberal). This study demonstrates how much the results from these two methods vary and develops an alternative method which more accurately estimates this remainder term. A method, called the minimum detectable compartment (MDC), is constructed so that an accurate dose estimate can be made with a realistic measure of the remainder term. The method for determining MDC uses standard hypothesis testing. Using an analogue of the traditional minimal detectable activity calculation, a model with and without constant compartments is fitted to the TAC. The size of the constant compartment is varied until the relative likelihood of the two models meets the desired measure of power and sensitivity. Computer simulations of a simple mono-exponential are used to demonstrate the MDC as a function of the model, the number of data points, the range of the data and the noise in the data. The MDC is a very sensitive function of the data range. It falls by more than 50% when the data range is increased from two to three half-lives. In addition, the MDC is moderately sensitive to the noise in the data and relatively insensitive to the number of data points. These findings suggest that the MDC method can also be uses a priori to indicate what type of data collection regimen is necessary to achieve a certain accuracy.

A risk index for pregnancy during anesthesia

STUDY OBJECTIVE

To determine the validity of limiting pregnancy testing only to females older than 14 years, hypothesizing that (1) if this recommendation were valid, we would find no incidence of pregnant patients receiving anesthesia in our department under age 15, and (2) by identifying all patients receiving anesthesia while pregnant versus those who are not pregnant might allow calculation of a relative risk index for pregnancy per age group.

DESIGN

A retrospective chart review.

SETTING

Department of Anesthesiology at Louisiana State University Medical Center in Shreveport.

MEASUREMENTS AND MAIN RESULTS

The relative numbers and ages of 1) all male versus female patients treated, 2) females presenting with viable pregnancy receiving anesthetic care, and 3) ages of conception in the youngest females were quantified to 4) correlate relative rates for pregnancy/anesthetic at each age. Of 16,033 anesthetics administered, 1,849 pregnant patients ages 13 to 44 years received 1,968 anesthetics (12.5% of total). One patient conceived at the age of 12. The rates of pregnant 13 (n = 4) and 14 (n = 24) year-olds in our anesthetized population equaled rates found with patients in the third and fourth decades of life, respectively.

CONCLUSIONS

Louisiana State University Medical Center's current departmental guideline to preoperatively test all patients aged 12 to 44 years is supported by the desire to identify pregnancy prior to anesthesia and the encountered pregnancy distribution and incidence. Although radiation is a known danger to fetal development, our radiology department tests only females who "fail to confirm in writing a nonpregnant state." While females younger than 15 years deserve the same consideration as 30- and 40-year-old patients, multiple ethical, pragmatic, economic, and theoretical considerations may mitigate the need for mandatory testing of all patients.

The effect of individual amino acids on ApoB100 and Lp(a) secretion by HepG2 cells

The rate at which HepG2 cells secrete apoB100 lipoproteins is inversely related to the concentration of amino acids in the medium (Zhang, Z., Sniderman, A. D., Kalant, D., Vu, H., Monge, J. C., Tao, Y., and Cianflone, K. (1993) J. Biol. Chem. 268, 26920-26926). The purpose of the present study was to determine the effect of individual amino acids on apoB100 and lipoprotein secretion. Asparagine was associated with modestly increased secretion. The branched chain amino acids (leucine, isoleucine, and valine) and lysine had minor inhibitory effects. The other amino acids, by contrast, decreased apoB secretion, although the magnitude of the effect varied considerably, the most potent being tyrosine, cysteine, phenylalanine, tryptophan, methionine, and glutamine. Although the effect on Lp(a) generally paralleled that on apoB100, it was usually much less pronounced. No amino acid caused a marked decrease in albumin, apoAI, or total protein secreted from the HepG2 cells. The amino acid effect on apoB was paralleled by similar decreases in secreted cholesterol ester (CE) primarily in the low density lipoprotein density range (d < 1.006-1.063 g/ml), although there was no significant change in intracellular CE. Neither intracellular nor secreted triglycerides (TG) or free cholesterol changed, resulting in a slightly larger TG-enriched particle being secreted. The effect was confirmed in cultured primary hamster hepatocytes, where a mixture of amino acids also caused a decrease in apoB secretion (up to 40%). ApoAI appeared to increase as with the HepG2 cells. Secreted CE paralleled apoB . There was no change in intracellular or secreted TG or free cholesterol, resulting in a substantially larger TG-rich particle being secreted. mRNA for apoB100 increased with asparagine, decreased moderately with branched chain amino acids, and decreased further with glutamine, as shown by dot blot and Northern blotting. Pulse-chase studies indicated that there was no change in apoB secretion efficiency under any condition. These results extend our previous observations by demonstrating specificity of the amino acid effect on apoB100 secretion. Although an effect on transcription is the likely mechanism, the exact basis for this remains to be determined.

Use of phthaloyl protecting group for the automated synthesis of 3'-[(hydroxypropyl)amino] and 3'-[(hydroxypropyl)triglycyl] oligonucleotide conjugates

The chemical stability of oligonucleotides (ODNs) containing 3'-propanolamine was investigated. Invariably, all the ODNs synthesized from Fmoc-protected 3-aminopropane-1,2-diol-CPG support gave a mixture of three compounds at the end of automated synthesis as analyzed by denaturing PAGE and HPLC. On the basis of analytical procedures, these compounds were identified to be 3'-[N-acetyl-N-(hydroxypropyl)amino],3'-[(hydroxypropyl)amino], and 3'-hydroxyl ODNs. The instability of the amino protecting group under the synthesis conditions was responsible for this observed heterogeneity. In order to evaluate the stability, a comparative study on the chemical stability of the ODN containing amino-protecting groups such as [(9-fluorenylmethyl)oxy]carbonyl (Fmoc), trifluoroacetyl (TFA), and phthaloyl was undertaken. The results indicate that the phthaloyl group provided the best stability for the synthesis of 3' amine-modified ODNs, and the protecting group is cleaved and deprotected in concentrated ammonium hydroxide:40% aqueous methylamine, 1:1, for 5-10 min, at 56 degrees C. The 3'-hydroxypropyl)triglycyl] ODN conjugates were also synthesized from Fmoc- and phthaloyl-protected (hydroxypropyl)triglycine-CPG supports.

Synthesis and properties of cholesteryl-modified triple-helix forming oligonucleotides containing a triglycyl linker

In order to enhance the nuclear uptake of triple-helix forming oligonucleotides (TFOs), a triglycylcholesterol group was attached to the 3' end. The peptide unit was introduced as a "labile" linker with the aim of releasing the oligonucleotide from the endosomes by the action of peptidases after crossing the cell membrane. Cholesteryl-CPG (8) and -TentaGel (9) supports containing 2-[N-(glycylglycylglycyl)amino]propane-1,3-diol (GAP-3) linker were prepared and used for automated oligonucleotide synthesis. The synthesis, characterization, and stability of these compounds are described.

Effects of albumin on lipid synthesis, apo B-100 secretion, and LDL catabolism in HepG2 cells

This study examines the effects of extracellular albumin on hepatic apo B-100 metabolism. To do so, a transformed human liver cell line, HepG2, was used as a hepatocyte model and the concentration of albumin in the medium was varied between 0 and 5 g%. Apo B-100 and apo A1 concentrations in the medium were determined by specific enzyme-linked immunoassay (ELISA) and intracellular synthesis of cholesterol ester and triglyceride were determined by addition of appropriate radiolabels to the medium. The data demonstrate that the reduction of extracellular albumin concentration resulted in increased apo B-100 concentration in the medium. Apo A1 secretion, however, was unaffected. While the differences in apo B-100 concentration in the medium were statistically significant (33% +/- 7%, P < 0.0025, 0 g% albumin compared to 5 g% albumin in the medium), the absolute magnitude of the effect under these conditions was relatively modest. Nevertheless, the changes were consistent and evident over incubation periods as long as 8 days. Of interest, although triglyceride synthesis was unaffected, cholesterol ester synthesis changed such that as albumin concentration decreased, synthesis of cholesterol ester increased paralleling the changes in apo B-100 (170% +/- 9%, P < 0.005). These findings were extended by studying interventions which altered cholesterol ester synthesis. Addition of the compound 58-035 (5 micrograms/ml, a specific inhibitor of acylcholesterol acyltransferase activity) resulted in substantial inhibition of cholesterol ester synthesis (39% to 66%, P < 0.025 and P < 0.005, respectively) and apo B-100 concentrations in the medium which decreased by 20% to 28%, P < 0.025. Triglyceride synthesis, in contrast, increased significantly by 32% P < 0.025. Therefore, addition of 58-035 confirmed the previous findings of a parallel relation between cholesterol ester synthesis and apo B-100 concentration in the medium. Nonetheless, albumin still had an additional inhibitory effect on cholesterol ester and apo B-100 secretion. Of interest, when chylomicron remnants (25 micrograms/ml cholesterol), which cause apo B-100 secretion to increase by more than threefold, were added to the medium, albumin now had a more pronounced absolute effect on apo B-100 secretion with a 48% inhibition observed as albumin was increased from 0 to 5 g% in the medium (P < 0.0125). The effect of extracellular albumin on the low density lipoprotein (LDL) pathway was also examined. No differences in non-specific cell association component were detected.(ABSTRACT TRUNCATED AT 400 WORDS)

The role of amino acids in ApoB100 synthesis and catabolism in human HepG2 cells

The object of this study was to examine the effects of extracellular amino acids on hepatic apoB100 metabolism using a transformed human liver cell line (HepG2) as a hepatocyte model. The data demonstrate that reduced extracellular amino acids resulted in marked increases in apoB100 concentrations in the medium (87 +/- 10% increase; p < 0.002). These data contrast with the effects of amino acids on secretion of total hepatic protein into the medium, which increased by 541 +/- 83% at 5.5 mg/ml amino acids compared to the low (0.5 mg/ml) amino acid medium (p < 0.01), pointing to a positive relationship between the concentration of amino acids in the medium and overall secretion of protein by the HepG2 cells. No significant effect of medium amino acid concentration on intracellular synthesis of cholesterol ester, cholesterol, triglyceride, or apoA1 secretion was evident. Amino acids also affected the activity of the low density lipoprotein pathway: at lower medium amino acid concentration, specific cell-associated radioactivity and cellular degradation were increased (117 +/- 24 and 233 +/- 13% at 0.5 versus 5.5 mg/ml amino acids, respectively). Pulse-chase analysis demonstrated that there was no difference in secretion efficiency of apoB (36 +/- 6 versus 46 +/- 8% in low versus high amino acid medium, respectively), but that the initial amount of [3H]apoB synthesized was greater in the low amino acid medium (10.5 +/- 3.8 versus 5.7 +/- 1.7 x 10(3) dpm [3H]apoB/mg of cell protein; p < 0.05). In contrast, the initial amount of [3H]albumin synthesized was much greater in the high amino acid medium (26.6 +/- 5.0 versus 54.6 +/- 19.0 x 10(3) dpm [3H]albumin/mg of cell protein in low versus high amino acid medium, respectively; p < 0.05). Slot blot analysis of apoB mRNA was 87 +/- 22% higher in lower amino acid medium as compared to the high amino acid medium (p < 0.01). These results demonstrate that amino acids have a profound negative regulatory effect on apoB synthesis and secretion and may shed light on the pathogenesis of some clinical dyslipidemias such as the increased plasma apoB levels in patients treated with continuous ambulatory peritoneal dialysis.

Effect of zidovudine on human placental trophoblast and Hofbauer cell functions

We have optimized a procedure to isolate placental trophoblasts and Hofbauer cells simultaneously in a quantity sufficient for short-term cultures and then used these placental cells to investigate the effects of zidovudine (ZDV) on trophoblast and Hofbauer cell functions. Of more than 10 term placentas tested, ZDV inhibits DNA synthesis of trophoblasts in a concentration-dependent manner with half the maximal inhibitory concentration (IC50) of 9.88 +/- 1.35 microM. Of the hormones evaluated, production of progesterone by trophoblasts is most sensitive to ZDV (IC50 = 3.65 +/- 0.29 microM). The inhibitory effect of ZDV on the secretion of placental lactogen and choriogonadotropin by the trophoblasts was detected only at a much higher concentration (> or = 60 microM). ZDV does not affect trophoblast or Hofbauer cell protein synthesis. Collectively, our results indicate that at clinically relevant concentrations (< or = 10 microM), ZDV significantly inhibits both the DNA synthesis of placental trophoblasts and their production of progesterone, while having a minimal effect on protein synthesis of both types of placental cells.

Effect of moderate hypertriglyceridemia on the relation of plasma total and LDL apo B levels

The risk of premature coronary artery disease is related to an important degree to the number of particles of low density lipoproteins (LDL) in plasma, an estimate given by measurement of LDL apo B. In clinical practise, though it is total, not LDL apo B, which is measured. The purpose of the present study therefore was to compare plasma total and LDL apo B in the presence and absence of moderate hypertriglyceridemia. The results demonstrate that within the range of plasma triglyceride levels examined, i.e., values of triglyceride up to 500 mg/dl, there is close correspondence between total and LDL apo B, with the latter more than 90% of the former. VLDL composition was also examined and two patterns found in hypertriglyceridemic patients: those with normal apo B had markedly lipid enriched VLDL while those with elevated apo B had VLDL which was normal in composition except for a moderate increase in triglyceride content. Thus total apo B within the circumstances studied reflects principally LDL apo B. Moreover measurement of apo B allows distinction between two different forms of hypertriglyceridemia, only one of which - that with an increased LDL particle number - has previous work shown to be associated with increased coronary risk. Total apo B, therefore, provides additional information not available from conventional plasma and lipoprotein lipids which allows more precise physiologic classification and may lead to more rational choice of pharmacologic therapy in normolipidemic and hypertriglyceridemic patients.

Jejunal angiodysplasia presenting as acute lower gastrointestinal bleeding

Vascular malformations of the bowel are uncommon sources of gastrointestinal (GI) tract bleeding with the majority of cases occurring in the right colon in elderly patients. Angiodysplasia can be difficult to diagnose, thereby complicating management as well. In the past, the diagnosis of angiodysplasia was rarely made early and rested upon a high index of suspicion in patients with lower GI bleeding and multiple negative diagnostic evaluations. Consequently, surgery was often performed late with increased morbidity and high recurrence rates. With the advent of pre- and intraoperative selective angiography, these vascular malformations are readily demonstrated in most cases and will often respond to conservative interventional radiologic procedures. Failing this, angiographic localization has made segmental resection both safe and quite accurate, thus obviating extensive, blind excision.

Metabolic response of Acylation Stimulating Protein to an oral fat load

Acylation Stimulating Protein (ASP) is a small (mol wt 14,000), basic (pI 9.0) protein present in human plasma. When examined in vitro with normal human cultured skin fibroblasts and adipocytes, ASP appears to be the most potent stimulant of triglyceride synthesis yet described. In this study, a competitive ELISA assay for ASP has been developed using immunospecific polyclonal antibodies, and ASP levels have been measured in seven normal subjects. Following an oral fat load, a sustained significant increase in ASP occurs, whereas after an oral glucose load, ASP levels do not change significantly. These responses are entirely opposite to those of insulin, which rises sharply but transiently after an oral glucose load but is unchanged after an oral fat load. Both the fasting and peak ASP levels were significantly related to the postprandial lipemia. These data provide the first in vivo evidence that Acylation Stimulating Protein may play an important physiological role in the normal response to an oral fat load.