Genomic Analysis and Surveillance of Respiratory Syncytial Virus (RSV) Using Wastewater-Based Epidemiology (WBE)

Respiratory syncytial virus (RSV) causes severe infections in infants, immunocompromised or elderly individuals resulting in annual epidemics of respiratory disease. Currently, limited clinical surveillance and the lack of predictable seasonal dynamics limits the public health response. Wastewater-based epidemiology (WBE) has recently been used globally as a key metric in determining prevalence of SARS-CoV-2 in the community but its application to other respiratory viruses is limited. In this study, we present an integrated genomic WBE approach, applying RT-qPCR and partial G-gene sequencing to track RSV levels and variants in the community. We report increasing detection of RSV in wastewater concomitant with increasing numbers of positive clinical cases. Analysis of wastewater-derived RSV sequences permitted identification of distinct circulating lineages within and between seasons. Altogether, our genomic WBE platform has the potential to complement ongoing global surveillance and aid the management of RSV by informing the timely deployment of pharmaceutical and non-pharmaceutical interventions.

Is cell culture a risky business? Risk analysis based on scientist survey data

Cell culture is a technique that requires vigilance from the researcher. Common cell culture problems, including contamination with microorganisms or cells from other cultures, can place the reliability and reproducibility of cell culture work at risk. Here we use survey data, contributed by research scientists based in Australia and New Zealand, to assess common cell culture risks and how these risks are managed in practice. Respondents show that sharing of cell lines between laboratories continues to be widespread. Arrangements for mycoplasma and authentication testing are increasingly in place, although scientists are often uncertain how to perform authentication testing. Additional risks are identified for preparation of frozen stocks, storage and shipping.

Transcription factors and th17 cell development in experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE), a widely studied animal model of human central nervous system demyelinating diseases such as multiple sclerosis, is a T-cell-mediated autoimmune disease involving effector T helper (Th) subsets such as Th and Th7. Recently, Th7 cells have been shown to play a major role in many autoimmune and other inflammatory diseases. The development of Th subsets is controlled by a complex network of cytokines and signaling and transcription molecules that act to augment the development of one cell type while restricting the development of other lineages. Here, we review the transcription factors (TFs) that are required for Th17 cell development in EAE and classify them into three types: major or essential such as RORγt and STAT3, an array of helper factors that work in combination with or regulate the expression of the major factors, and regulatory TFs that attenuate the expression of Th17 genes. The plasticity of the Th17 cell lineage is also discussed in relation to the interaction of TFs that play a major role in the development of other Th or regulatory T cell (Treg) lineages such as T-bet and Foxp3 with the Th17 TFs.

Time to viral load suppression in antiretroviral-naive and -experienced HIV-infected pregnant women on highly active antiretroviral therapy: implications for pregnant women presenting late in gestation

OBJECTIVE

To compare time to achieve viral load <400 copies/ml and <1000 copies/ml in HIV-infected antiretroviral (ARV) -naive versus ARV-experienced pregnant women on highly active antiretroviral therapy (HAART).

DESIGN

Retrospective cohort study.

SETTING

Three university medical centers, USA.

POPULATION

HIV-infected pregnant women initiated or restarted on HAART during pregnancy.

METHODS

We calculated time to viral load <400 copies/ml and <1000 copies/ml in HIV-infected pregnant women on HAART who reported at least 50% adherence, stratifying based on previous ARV exposure history.

MAIN OUTCOME MEASURES

Time to HIV viral load <400 copies/ml and <1000 copies/ml.

RESULTS

We evaluated 138 HIV-infected pregnant women, comprising 76 ARV-naive and 62 ARV-experienced. Ninety-three percent of ARV-naive women achieved a viral load < 400 copies/ml during pregnancy compared with 92% of ARV-experienced women (P = 0.82). The median number of days to achieve a viral load < 400 copies/ml in the ARV-naive cohort was 25.0 (range 3.5-133; interquartile range 16-34) days compared with 27.0 (range 8-162.5; interquartile range 18.5-54.3) days in the ARV-experienced cohort (P = 0.02). In a multiple predictor analysis, women with higher adherence (adjusted relative hazard [aRH] per 10% increase in adherence 1.29, 95% confidence interval [CI] 1.08-1.54, P = 0.01) and receiving a non-nucleotide reverse transcriptase inhibitor (NNRTI) -based regimen (aRH 2.48, 95% CI 1.33-4.63, P = 0.01) were more likely to achieve viral load <400 copies/ml earlier. Increased baseline HIV log10 viral load was associated with a later time of achieving viral load <400 copies/ml (aRH 0.60, 95% CI 0.39-0.92, P = 0.02). In a corresponding model of time to achieve viral load <1000 copies/ml, adherence (aRH per 10% increase in adherence 1.79, 95% CI 1.34-2.39, P < 0.001), receipt of NNRTI (aRH 2.95, 95% CI 1.23-7.06, P = 0.02), and CD4 cell count (aRH per 50 count increase in CD4 1.12, 95% CI 1.03-1.22, P = 0.01) were associated with an earlier time to achieve viral load below this threshold. Increasing baseline HIV log10 viral load was associated with a longer time of achieving viral load <1000 copies/ml (aRH 0.54, 95% CI 0.34-0.86, P = 0.01). In multiple predictor models, previous ARV exposure was not significantly associated with time to achieve viral load below thresholds of <400 copies/ml and <1000 copies/ml.

CONCLUSIONS

Pregnant women with ≥50% adherence, whether ARV-naive or ARV-experienced, on average achieve a viral load <400 copies/ml within a median of 26 days and a viral load of <1000 copies/ml within a median of 14 days of HAART initiation. Increased adherence, receipt of NNRTI-based regimen and lower baseline HIV log10 viral load were all statistically significant predictors of earlier time to achieve viral load <400 copies/ml and <1000 copies/ml. Increased CD4 count was statistically significant as a predictor of earlier time to achieve viral load <1000 copies/ml.

Abstract 4218: Validation of the Ion AmpliSeq™ Comprehensive Cancer Panel (CCP) using castPCR™ technologies

Somatic mutation has been implicated in many aspects of cancer such as susceptibility, diagnosis, prognosis, drug response and tumor progress. Detection of somatic mutation is of wide interest in cancer research. The rapid advances in next generation sequencing (NGS) technologies have transformed cancer research. For example, the Ion AmpliSeq™ technology enables the selective amplification of 10s to 1000s of target sequences in a single multiplexed PCR and meshes seamlessly with the Ion semiconductor sequencing platform. The Ion Ampliseq™ Comprehensive Cancer Panel (CCP) provides ready-access to hundreds of genes, making it ideal for broad targeted re-sequencing studies. Alternative technologies are in demand to validate the NGS data orthogonally and screen hundreds or more cancer samples to evaluate mutation patterns, prevalence and frequencies in population. Here, we have demonstrated the utility of TaqMan® Mutation Detection Assays using our competitive allele specific TaqMan® PCR (castPCR™) technology in validation of Ion Torrent sequencing data. In this study, we applied the Ion Ampliseq™ Comprehensive Cancer Panel (CCP) panel to NCI-60 cell lines (MCF-7, MDA-MB-231, DU-145, PC-3, SK-MEL- 28) derived from breast, prostate, and skin cancers on Ion Torrent PGM sequencer. We confirmed previously reported mutations in these cell lines and identified the mutations that were not reported before, including missense and non-coding mutations. We then selected a subset of mutation targets from the cancer panel for castPCR validation including the genes of KRAS. EGFR, BRAF, NRAS, PIK3CA, PTEN, KIT, TP53, and more. Since limited sample quantity has been a challenging issue for most cancer researchers, especially for those who are interested in testing multi-targets by qPCR, we developed a preamplification method to enrich the targets of interest prior to running castPCR assays. We compared the Cq values of on-targets and off-targets from preamplified samples and non-preamplified samples, and the data indicates that our preamplification strategy not only provides roughly100 fold target enrichment but also maintains specificity during the preamplification process. For mutation detection, we showed that the mutation data from castPCR™ and from Ion Torrent PGM sequencer share high concordance for any given mutations. The detailed comparison and analysis will be presented and discussed. Our results demonstrate that castPCR™ technology is a valuable validation tool for next generation sequencing. The combination of Ion Torrent sequencing and castPCR validation empowers cancer researchers to understand the roles that somatic mutation plays in cancer.

Citation Format: Kelly Li, Cora Woo, Mokang Mouanoutoua, Bonnie Moy, Emanuel Langit, Pius Brzoska, Xiaoqing You, Sejal Desai, David Keys, Junko Stevens, Benjamin Kong, Mark Shannon, Shiaw-Min Chen, David Ruff, Chieh-Yuan Li, David Joun, Iris Casuga, Robert Bennett. Validation of the Ion AmpliSeq™ Comprehensive Cancer Panel (CCP) using castPCR™ technologies. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4218. doi:10.1158/1538-7445.AM2013-4218

Natural history of acoustic neuromas

The growth rate of acoustic neuromas was studied in a series of 50 patients who underwent follow-up imaging studies, since surgery was not performed after the initial diagnostic study or only performed after the follow-up studies. In 50% of the cases the tumor did not grow during the length of the follow-up. In the other patients the growth was less than 50% of the original tumor size in all but four. No correlation was observed between tumor growth, length of the follow-up, and age of the patient. Our results suggest a change in the management of this benign tumor.

Applications of quantitative polymerase chain reaction protein assays during reprogramming

The capability to reprogram human somatic cells to induced pluripotent stem cells (iPSCs) has opened a new area of biology and provides unprecedented access to patient-specific iPSCs for drug screening, disease models, and transplantation therapies. Although the process of obtaining iPSC lines is technically simple, reprogramming is a slow and inefficient process consisting of a largely uncharacterized chain of molecular events. To date, researchers have reported a wide range of reprogramming efficiencies, from <0.01% to >1%, depending on the specific reprogramming factors used, the mode of delivery of the reprogramming factors, properties of the starting cells, and culture conditions. We have applied a quantitative polymerase chain reaction methodology, TaqMan Protein Assays to directly quantify the kinetics, and cellular levels of crucial transcription factors during the reprogramming process. Further, we have used the assays to ascertain the threshold levels of reprogramming protein factors required to generate iPSC colonies, to characterize the protein expression signatures of different iPSC lines, and to rapidly identify iPS versus non-iPSC colonies based on expression of pluripotency markers. These data demonstrate that TaqMan Protein Assays can be used as tools to dissect and gain greater understanding of the mechanisms guiding reprogramming and to further characterize individual established iPSC lines.

Expression and interdependencies of pluripotency factors LIN28, OCT3/4, NANOG and SOX2 in human testicular germ cells and tumours of the testis

OCT3/4, NANOG, SOX2 and, most recently, LIN28 have been identified as key regulators of pluripotency in mammalian embryonic and induced stem cells, and are proven to be crucial for generation of the mouse germ-cell lineage. These factors are a hallmark of certain histological types of germ-cell tumours (GCTs). Here, we report novel information on the temporal and spatial expression pattern of LIN28 during normal human male germ-cell development as well as various types of GCTs. To investigate LIN28 expression, immunohistochemical analyses and quantitative proximity ligation assay-based TaqMan protein assays were applied on snap-frozen and formalin-fixed, paraffin-embedded samples as well as representative cell lines. LIN28 was found in primordial germ cells, gonocytes and pre-spermatogonia, in contrast to OCT3/4 and NANOG, which were found only in the first two stages. LIN28 was also found in all precursor lesions (carcinoma in situ and gonadoblastoma) of type II GCTs, as well as the invasive components seminoma and the non-seminomatous elements embryonal carcinoma and yolk sac tumour. Choriocarcinoma showed a heterogeneous pattern, while teratomas and spermatocytic seminomas (type III GCTs) were negative. This expression pattern suggests that LIN28 is associated with malignant behaviour of type II GCTs. Cell line experiments involving siRNA knockdown of LIN28, OCT3/4 and SOX2 showed that LIN28 plays a role in the maintenance of the undifferentiated state of both seminoma and embryonal carcinoma, closely linked to, and likely upstream of OCT3/4 and NANOG. In conclusion, LIN28 regulates the differentiation status of seminoma and embryonal carcinoma and is likely to play a related role in normal human germ-cell development.

Expanding applications of protein analysis using proximity ligation and qPCR

The correlation of gene and protein expression changes in biological systems has been hampered by the need for separate sample handling and analysis platforms for nucleic acids and proteins. In contrast to the simple, rapid, and flexible workflow of quantitative PCR (qPCR) methods, which enable characterization of several classes of nucleic acid biomarkers (i.e. DNA, mRNA, and microRNAs), protein analysis methods such as Western blotting are cumbersome, laborious, and much less quantitative. However, TaqMan(R) Protein Assays, which use the proximity ligation assay (PLA) technology, now expand the range of qPCR applications to include the direct detection of proteins through the amplification of a surrogate DNA template after antibody binding. Here we describe an integrated qPCR approach for measuring relative changes in gene and protein expression from the same starting sample and on a single analytical platform that pairs TaqMan Gene Expression (GEx) Assays with TaqMan Protein Assays. We have monitored the changes in mRNA, microRNA, and protein expression of relevant biomarkers in the pluripotent human embryonal carcinoma cell line, NTERA2, upon differentiation to neuronal cells. In addition, TaqMan Protein Assays have been used to monitor protein expression in induced pluripotent stem cells (iPSC) that have been reprogrammed from human somatic cells. The data presented establishes a general paradigm utilizing real-time PCR instruments and reagents for studying the relationship between the stem cell transcriptome and proteome.

Abstract 1163: Sensitive and specific detection of clinically relevant proteins in human testicular germ cell tumors using proximity ligation and quantitative PCR

Human testicular germ cell tumors (TGCTs) are the most frequent solid cancer in Caucasian males between the ages of 15 and 45 years. In spite of the high success rate of current treatment strategies (surgery, irradiation and chemotherapy), TGCTs are the second leading cause of death in this age group. The initiating event, leading to carcinoma in situ (CIS), occurs during embryonal development, offering a window of opportunity for early detection and intervention, thereby preventing the need for intensive (systemic) treatment. CIS is the malignant counterpart of a primordial germ cell, and can be effectively diagnosed using immunohistochemisty for OCT3/4, NANOG, c-KIT and its ligand (stem cell factor, SCF). In addition, SOX17 and SOX2 are informative for the diagnosis of the invasive components seminoma and embryonal carcinoma. Currently, in a clinical setting, these proteins are detected using predominantly immunohistochemistry, an approach that is labor-intensive and non-quantitative. Here we present data on the detection of these proteins using a novel qPCR-based method, Taqman Protein Expression Assay, which is based on the Proximity Ligation Assay (PLATM) technology. The method was first validated on negative controls and a series of TGCT-derived cell lines with efficient siRNA-induced down-regulation of the targets, an informative system for investigating stem cell regulatory circuits. Subsequently, the assay was further developed to enable analysis of both snap frozen and formalin-fixed paraffin-embedded (FFPE) tissues. The assays were found to be fast (results in less than 1 day), highly reproducible (SD less than 0.2 CTs), sensitive (able to detect target protein from as few as 10-100 cells, depending on the level of expression of the protein under investigation), and quantitative. Taqman Protein Expression Assays therefore allow the systematic analysis of multiple proteins within a single small sample in a high throughput set up, and offer unique opportunities for sensitive, specific and quantitative protein detection in both experimental and clinical studies.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1163.

Guidelines on the insertion and management of central venous access devices in adults

Central venous access devices are used in many branched of medicine where venous access is required for either long-term or a short-term care. These guidelines review the types of access devices available and make a number of major recommendations. Their respective advantages and disadvantages in various clinical settings are outlined. Patient care prior to, and immediately following insertion is discussed in the context of possible complications and how these are best avoided. There is a section addressing long-term care of in-dwelling devices. Techniques of insertion and removal are reviewed and management of the problems which are most likely to occur following insertion including infection, misplacement and thrombosis are discussed. Care of patients with coagulopathies is addressed and there is a section addressing catheter-related problems.

EGFR mutations (muts), IHC and FISH status, and chromosome 7 gene copy number combined with pAkt expression as potential predictors of survival in non-small cell lung cancer (NSCLC) patients (pts) treated with gefitinib (GEF)

7182

Background: EGFR and pAkt expression by immunohistochemistry (IHC), muts, and FISH status have been identified as possible molecular predictors for GEF efficacy in NSCLC (Cappuzzo, et. al, JNCI, 2005). The goal of this study was to independently evaluate these findings regarding survival (surv), and to assess the predictive value of mean chromosome 7 copy number/cell (C7). Methods: 150 consecutive Expanded Access Trial pts with >1 week GEF therapy were included for analysis. IHC (present vs not detected) was performed for 87 pts, and 58 pts were analyzed for muts by SSCP, mut-specific PCR, and sequencing. Tissue from 81 pts was evaluated for EGFR and C7 gene copy numbers by fluorescence in situ hybridization (FISH). Results: 150 pts (77 female, 73 male; median (md) age 67; 85 adenocarcinoma) received GEF; md follow-up was 5.8 months (mo). Overall response was 8% (2 CR, 10 PR); 56 pts had stable disease. Md Kaplan-Meier surv was 5.9 mo. IHC revealed that 47/87 pts (54%) had EGFR+, and 36/75 pts (48%) had pAkt + tumors. pAkt+ pts had significantly (sig) longer surv than pAkt− pts (11.4 vs 5.8 mo, p < .05). High polysomy was seen in 36/81 pts (44%) who were designated FISH+; 45 pts were FISH−. EGFR IHC and FISH positivity were not sig associated with surv. C7 was defined as low (<3.6, 63 pts) or high (≥3.6, 18 pts); md surv was 6.6 and 17.1 mo, respectively, p < .01. Muts were found in 17/58 tumors (29%). Md surv for pts with and without muts was 23.8 and 7.9 mo, respectively, p < .07. EGFR IHC− pAkt− pts (18 pts) had sig shorter surv than 57 pts with any pos value (4.7 vs 8.8 mo, p < .02). Double-positive pts had sig longer surv than pts with any neg value. Conclusions: These findings resemble but do not duplicate those reported by Cappuzzo, et al. Additionally, high C7, alone or combined with pAKT, may be an important predictor for GEF efficacy in NSCLC. Further studies of C7, a technically simple and reproducible FISH assay, are warranted.

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An efficient and high-throughput approach for experimental validation of novel human gene predictions

A highly automated RT-PCR-based approach has been established to validate novel human gene predictions with no prior experimental evidence of mRNA splicing (ab initio predictions). Ab initio gene predictions were selected for high-throughput validation using predicted protein classification, sequence similarity to other genomes, colocalization with an MPSS tag, or microarray expression. Initial microarray prioritization followed by RT-PCR validation was the most efficient combination, resulting in approximately 35% of the ab initio predictions being validated by RT-PCR. Of the 7252 novel genes that were prioritized and processed, 796 constituted real transcripts. In addition, high-throughput RACE successfully extended the 5' and/or 3' ends of >60% of RT-PCR-validated genes. Reevaluation of these transcripts produced 574 novel transcripts using RefSeq as a reference. RT-PCR sequencing in combination with RACE on ab initio gene predictions could be used to define the transcriptome across all species.

Hospital planning for acts of terrorism and other public health emergencies involving children

In today's world the increased potential of terrorist attacks places unique burdens and consequences on health care workers. Hospitals and hospital personnel must now be prepared to react immediately to such events. They must also implement, in advance, policies to protect their own health care personnel while providing care to victims. In this review, we discuss the four major forms of mass casualty terrorism (biological, chemical, nuclear, and thermomechanical) including clinical signs and symptoms for each, the impact on health care personnel, and special considerations for children. We will then outline key principles of hospital preparation with regard to paediatrics in anticipation of such emergencies.

Recreational music-making modulates the human stress response: a preliminary individualized gene expression strategy

BACKGROUND

A central component of the complex human biological stress response is the modulation of the neuro-endocrine-immune system with its intricate feedback loops that support homeostatic regulation. Well-documented marked gene expression variability among human and animal subjects coupled with sample collection timing and delayed effects, as well as a host of molecular detection challenges renders the quest for deciphering the human biological stress response challenging from many perspectives.

MATERIAL/METHODS

A novel Recreational Music-Making (RMM) program was used in combination with a new strategy for peripheral blood gene expression analysis to assess individualized genomic stress induction signatures. The expression of 45 immune response-related genes was determined using a multiplex preamplification step prior to conventional quantitative Real Time Polymerase Chain Reaction (qRT-PCR) mRNA analysis to characterize the multidimensional biological impact of a 2-phase controlled stress induction/amelioration experimental protocol in 32 randomly assigned individuals.

RESULTS

In subjects performing the RMM activity following a 1-hour stress induction protocol, 19 out of 45 markers demonstrated reversal with significant (P = 0.05) Pearson correlations in contrast to 6 out of 45 markers in the resting control group and 0 out of 45 in the ongoing stressor group.

CONCLUSIONS

The resultant amelioration of stress-induced genomic expression supports the underlying premise that RMM warrants additional consideration as a rational choice within our armamentarium of stress reduction strategies. Modulation of individualized genomic stress induction signatures in peripheral blood presents a new opportunity for elucidating the dynamics of the human stress response.

Direct signaling by the BMP type II receptor via the cytoskeletal regulator LIMK1

Bone morphogenetic proteins (BMPs) regulate multiple cellular processes, including cell differentiation and migration. Their signals are transduced by the kinase receptors BMPR-I and BMPR-II, leading to Smad transcription factor activation via BMPR-I. LIM kinase (LIMK) 1 is a key regulator of actin dynamics as it phosphorylates and inactivates cofilin, an actin depolymerizing factor. During a search for LIMK1-interacting proteins, we isolated clones encompassing the tail region of BMPR-II. Although the BMPR-II tail is not involved in BMP signaling via Smad proteins, mutations truncating this domain are present in patients with primary pulmonary hypertension (PPH). Further analysis revealed that the interaction between LIMK1 and BMPR-II inhibited LIMK1's ability to phosphorylate cofilin, which could then be alleviated by addition of BMP4. A BMPR-II mutant containing the smallest COOH-terminal truncation described in PPH failed to bind or inhibit LIMK1. This study identifies the first function of the BMPR-II tail domain and suggests that the deregulation of actin dynamics may contribute to the etiology of PPH.

Differential expansion of zinc-finger transcription factor loci in homologous human and mouse gene clusters

Mammalian genomes carry hundreds of Krüppel-type zinc finger (ZNF) genes, most of which reside in familial clusters. ZNF genes encoding Krüppel-associated box (KRAB) motifs are especially prone to this type of tandem organization. Despite their prevalence, little is known about the functions or evolutionary histories of these clustered gene families. Here we describe a homologous pair of human and mouse KRAB-ZNF gene clusters containing 21 human and 10 mouse genes, respectively. Evolutionary analysis uncovered only three pairs of putative orthologs and two cases where a single gene in one species is related to multiple genes in the other; several human genes have no obvious homolog in mouse. We deduce that duplication and loss of ancestral cluster members occurred independently in the primate and rodent lineages after divergence, yielding substantially different ZNF gene repertoires in humans and mice. Differences in expression patterns and sequence divergence within the DNA binding regions of predicted proteins suggest that the duplicated genes have acquired novel functions over evolutionary time. Since KRAB-ZNF proteins are predicted to function as transcriptional regulators, the elaboration of new lineage-specific genes in this and other clustered ZNF families is likely to have had a significant impact on species-specific aspects of biology.

Coprescribing and codispensing of cisapride and contraindicated drugs

CONTEXT

Cisapride, an oral prokinetic drug indicated for the symptomatic treatment of nocturnal heartburn due to gastroesophageal reflux disease, was approved by the US Food and Drug Administration in July 1993. After reports of serious cardiac arrhythmias and deaths during administration of cisapride, most involving concomitant exposure to another drug, a series of label changes and warnings were issued in February 1995, October 1995, June 1998, and June 1999. Cisapride was removed from general distribution in July 2000.

OBJECTIVE

To determine the frequency of contraindicted coprescribing and codispensings, in which cisapride and a contraindicated drug were prescribed or dispensed to the same patient for overlapping periods, and the proportion of contraindicated coprescribing by the same physicians and codispensing by the same pharmacies.

DESIGN AND SETTING

Retrospective study of prescription claims from a managed care organization database for all patients with cisapride prescriptions between July 1993 and December 1998.

PARTICIPANTS

A total of 38 757 adult and pediatric patients who had a cisapride prescription immediately preceded by at least 60 days of insurance eligibility.

MAIN OUTCOME MEASURE

Proportion of cisapride prescriptions or dispensing occurring during the same treatment period as a drug contraindicated at that time prescribed by the same physicians or dispensed by the same pharmacies.

RESULTS

Of 131 485 cisapride prescriptions dispensed after the warnings began, 4414 (3.4%) overlapped with at least 1 drug contraindicated in the labeling at the time of the prescription. Of all overlapping prescription pairs, 2190 (50%) were by the same physicians, 3908 (89%) were by the same pharmacies, and 765 (17%) were dispensed on the same day.

CONCLUSION

Prescriptions dispensed by the same pharmacies accounted for a far higher proportion of contraindicated medication pairs than prescriptions from the same physicians. The pharmacy may be an important and underutilized intervention point to prevent contraindicated drugs from being used together.

Nephrotoxicity after acute severe acetaminophen poisoning in adolescents

OBJECTIVE

To determine the rate of acetaminophen related nephrotoxicity in adolescents who present after acute severe acetaminophen intoxication and to identify potential predictors of this outcome.

STUDY DESIGN

Retrospective analysis of consecutive patients between the ages of 12 and 18 years who were admitted at a tertiary care children's hospital for treatment of acute severe acetaminophen intoxication with N-acetylcysteine. The main outcome measure was the frequency of acetaminophen-related nephrotoxicity, defined as abnormal blood urea nitrogen (>6.4 mmol/L or > 18 mg/dL) and/or elevated creatinine (97.2 micromol/L or > 1.1 mg/dL) in association with one or both of the following: elevated blood pressure (systolic blood pressure > 140 mm Hg/diastolic blood pressure >85) or abnormal urinalysis (urinalysis with hematuria or proteinuria). Statistical analyses used were measures of central tendency, Student's t-test, Mann-Whitney, and multivariate logistic regression.

RESULTS

Fourty-five patients were included. Acetaminophen-related nephrotoxicity occurred in 4 (8.9%) cases. One victim developed severe renal injury in association with elevated hepatic transaminases. Intergroup analyses revealed no statistically significant association between acetaminophen-related nephrotoxicity and amount/kg of acute severe acetaminophen ingested, delay in treatment with N-acetylcysteine, or measures of hepaticfunction.

CONCLUSIONS

Acetaminophen-related nephrotoxicity occurred in 8.9% [95% CI: 4.52, 20.48] of children with severe overdose. There are no obvious predictors of this complication of acetaminophen overdose. Because the occurrence of renal injury can not be predicted, serial blood pressure, blood urea nitrogen/creatinine, and urinalysis should be considered an integral part of the management of children with acute, severe acetaminophen intoxication.

Harris Galante cementless acetabular replacement in avascular necrosis

We describe the results of 76 total arthroplasties of the hip for stage-III or stage-IV avascular necrosis of the femoral head. Harris Galante Porous cups were used in 63 patients between 1986 and 1994 and followed prospectively. We reviewed 70 hips with a follow-up of more than five years (mean 7.6). At the latest review the mean Harris Hip Score had improved from a preoperative value of 29 +/- 14.7 to 94 +/- 6.8. Radiologically, there was no evidence of acetabular migration. The rate of revision for the femoral component was 8.6%, three being undertaken for loosening and three to allow downsizing of the femoral head. The rate of revision for the acetabular component was 7.1% (five cups). At the time of revision none of the cups was clinically loose, and only required the liner to be changed. The rate of complications was low with no case of deep infection or dislocation, but nine of the 76 hips (11.8%) showed grade-III heterotopic ossification. Previous studies of patients undergoing cemented total hip arthroplasty for the treatment of advanced avascular necrosis have indicated a high incidence of loosening of the acetabular component. Our findings show good medium-term results using the Harris Galante Porous cup for acetabular reconstruction, together with a variety of cemented femoral components, for the treatment of this difficult problem.

Tandem zinc-finger gene families in mammals: insights and unanswered questions

Evidence for the remarkable conservation of mammalian genomes, in both content and organization of resident genes, is rapidly emerging from comparative mapping studies. The frequent occurrence of familial gene clustering, presumably reflecting a history of tandem in situ duplications starting from a single ancestral gene, is also apparent from these analyses. Genes encoding Kruppel-type zinc-finger (ZNF) proteins, including those containing Kruppel-associated box (KRAB) motifs, are particularly prone to such clustered organization. Existing data suggest that genes in KRAB-ZNF gene clusters have diverged in sequence and expression patterns, possibly yielding families of proteins with distinct, yet related, functions. Comparative mapping studies indicate that at least some of the genes within these clusters in mammals were elaborated prior to the divergence of mammalian orders and, subsequently, have been conserved. These data suggest a possible role for these tandem KRAB-ZNF gene families in mammalian evolution.