Public policy issues in nonprofit conversions: an overview

Conversions raise two critical policy questions: First, does ownership form (nonprofit or for-profit) make any difference to delivery of health care? Second, when conversions occur, how are charitable assets and purpose preserved? This paper addresses both questions, based on a review of evidence and experience. On the first question we conclude that, overall, nonprofit ownership enhances the potential for community benefit. However, that potential may be better realized by requiring nonprofits to meet minimum community benefit standards and possibly by mitigating pressure on institutions to convert. On the second question, we conclude that more states should take legislative action to establish a formal oversight process for conversions. Without public consideration of how much money to set aside and for what purpose, conversions pose the risk that communities will lose significant services and resources.

Characterization of two scleroderma autoimmune antigens that copurify with human ribonuclease P

Human RNase P has been purified more than 2000-fold from HeLa cells. In addition to the RNA component, H1 RNA, polypeptides of molecular masses 14, 20, 25, 30, 38, and 40 kDa copurify with the enzyme activity. Sera from two different patients with the autoimmune disease scleroderma were used to immunodeplete human RNase P activity. These same sera cross-reacted on immunoblots with two of the copurifying polypeptides, p30 and p38, whereas an autoimmune serum that does not immunodeplete RNase P activity did not react with these proteins. Peptide fragments derived from purified p30 and p38 facilitated the molecular cloning and sequencing of cDNAs coding for these two polypeptides, which are now designated as Rpp30 and Rpp38, respectively. RPP38 cDNA encodes a polypeptide that may be identical to a previously identified antigen of approximately 40 kDa, which is immunoprecipitated by Th and To autoimmune antisera, and that has been implicated as a protein subunit of human RNase P by virtue of its ability to bind to H1 RNA in vitro. The second autoimmune antigen, Rpp30, as such, has not been described previously.

Obstetric complications and age-related changes in brain morphology in schizophrenia

Birth problems can lead to changes in brain morphology in the general population and an increased prevalence of both birth problems and altered brain morphology are found in patients with schizophrenia. The purpose of this study was to test the hypothesis that these two findings are related. Birth history and the size of ventricular and sulcal spaces from nine regions of the brain were assessed in 80 male subjects with schizophrenia. No differences were found between patients with and those without a history of birth problems for the size of any brain space; however, ventricular size increased significantly with age in patients who had no birth complications but not in patients with a history of birth problems. The size of cortical sulci increased with age in patients with and those without a history of birth problems. These results suggest that region-specific rates of change in size may identify clinically meaningful patients subgroups.

The RNA subunit of ribonuclease P from the zebrafish, Danio rerio

A simple strategy has been devised to identify the gene encoding the RNA subunit of RNase P from the zebrafish, Danio rerio. The sequence obtained by amplification of genomic DNA with primers based on sequences common to two other vertebrates was confirmed by reverse transcription and amplification of RNA from a partially purified preparation of the holoenzyme. The 5' and 3' ends were determined by cyclizing the RNA, followed by reverse transcription and sequencing across the ligated RNA junction. The zebrafish sequence is 63% identical to that of Xenopus laevis nuclear RNase P RNA and 69% identical to the human RNase P RNA. A consensus secondary structure was constructed based on these nucleotide identities and on the many compensatory base changes in several regions among these three RNAs. The strategy used to obtain the zebrafish sequence should be useful in deriving analogous gene sequences from diverse classes of eukaryotes.

Requirements for cleavage by a modified RNase P of a small model substrate

M1 RNA, the catalytic RNA subunit of RNase P from Escherichia coli, has been covalently linked at its 3' terminus to oligonucleotides (guide sequences) that guide the enzyme to target RNAs through hybridization with the target sequences. These constructs (M1GS RNAs) have been used to determine some minimal features of model substrates. As few as 3 bp on the 3' side of the site of cleavage in a substrate complex and 1 nt on the 5' side are required for cleavage to occur. The cytosines in the 3' terminal CCA sequence of the model substrates are important for cleavage efficiency but not cleavage site selection. A purine (base-paired or not) at the 3' side of the cleavage site is important both for cleavage site selection and efficiency. M1GS RNAs provide both a simple system for characterization of the reaction governed by M1 RNA and a tool for gene therapy.

Mapping in three dimensions of regions in a catalytic RNA protected from attack by an Fe(II)-EDTA reagent

The accessibility of the ribose groups in the phosphodiester chain of M1 RNA, the catalytic subunit of ribonuclease P from Escherichia coli, has been probed with an Fe(II)-EDTA reagent when the RNA is alone in solution, when it is in a complex with a tRNA precursor substrate, and when it is in the holoenzyme complex with its cofactor, C5 protein. The regions found to be protected under these various conditions, as well as those previously identified in other chemical probing experiments, have been mapped on a three-dimensional working model of M1 RNA and are generally compatible with the previously proposed placement of the substrate on the enzyme and with previous data and inferences regarding the interactions of C5 protein with M1 RNA. On the basis of the accessibilities of the C(4') atoms, refinements have been introduced in the model to accommodate the Fe(II)-EDTA protection data. The protein cofactor makes contact with several helical regions of the catalytic RNA on the opposite side of the surface to which substrates bind.

Cleavage by RNase P of gene N mRNA reduces bacteriophage lambda burst size

RNase P, an enzyme essential for tRNA biosynthesis, can be directed to cleave any RNA when the target RNA is in a complex with a short, complementary oligonucleotide called an external guide sequence (EGS). RNase P from Escherichia coli can cleave phage lambda N mRNA in vitro or in vivo when the mRNA is in a complex with an EGS. The EGS can either be separate from or covalently linked to M1 RNA, the catalytic RNA subunit of RNase P. The requirement for Mg2+ in the reaction in vitro is lower when the EGS is covalently linked to M1 RNA. Substrates made of DNA can also be cleaved by RNase P in vitro in complexes with RNA EGSs. When either kind of EGS construct is used in vivo, burst size of phage lambda is reduced by > or = 40%. Reduction in burst size depends on efficient expression of the EGS constructs. The product of phage lambda gene N appears to function in a stoichiometric fashion.

Artificial regulation of gene expression in Escherichia coli by RNase P

Plasmids encoding various external guide sequences (EGSs) were constructed and inserted into Escherichia coli. In strains harboring the appropriate plasmids, the expression of fully induced beta-galactosidase and alkaline phosphatase activity was reduced by more than 50%, while no reduction in such activity was observed in strains with non-specific EGSs. The inhibition of gene expression was virtually abolished at restrictive temperatures in strains that were temperature-sensitive for RNase P (EC 3.1.26.5). Northern blot analysis showed that the steady-state copy number of EGS RNAs was several hundred per cell in vivo. A plasmid that contained a gene for M1 RNA covalently linked to a specific EGS reduced the level of expression of a suppressor tRNA that was encoded by a separate plasmid. Similar methods can be used to regulate gene expression in E. coli and to mimic the properties of cold-sensitive mutants.

Characterization of RNA with unusual electrophoretic mobility from tissues of patients with Crohn's disease

RNAs from tissues of patients with Crohn's disease that migrate off the diagonal in a two-dimensional gel electrophoresis system were partially characterized. One of the RNA species was a discrete cleavage product of region V2-9 of 28S rRNA; another is a conformer or variant of 5.8S rRNA; and a third is a mixture of unidentified fragments with mobility similar to that of 7S RNA. The yield of these species from resected tissue and their visualization by silver staining was very sensitive to the details of the preparative procedure. No evidence of viroid-like RNA was found within the range of molecular sizes (< 7S) that we examined.

Regional cortical anatomy and clozapine response in refractory schizophrenia

Regional measures of cortical sulcal and ventricular enlargement on computed tomography scan were studied in a clinical sample of patients treated with clozapine. Cortical sulci were significantly enlarged in clozapine nonresponders compared to responders. The Clinical Global Impressions score at discharge was related to the size of the posterior frontal and lateral temporal sulci, with large sulci predicting a poorer response to clozapine treatment.

Routine assessment of patient progress: a multiformat, change-sensitive nurses' instrument for assessing psychotic inpatients

A new instrument, the Routine Assessment of Patient Progress (RAPP), is a standardized scale with a unique format that allows trained nurses to incorporate both interview and observational data into a comprehensive assessment of psychiatric inpatients. The scale was developed to accurately document treatment effects, assist in treatment planning, and provide ancillary judgments of psychopathology that may affect diagnosis. The RAPP demonstrates satisfactory interrater reliability and internal consistency. The RAPP total score and its two subscales correlated highly, where expected, with an observation-based nursing scale, global measures, and an interview-based psychopathology scale. RAPP scores demonstrated sensitivity to change over time in patient functioning. It reliably discriminated among patients discharged to settings with varying degrees of independent living. The use of the RAPP over several years on a psychiatric inpatient unit has shown it to be a practical clinical tool that eases nurses' charting demands, helps create care plans, and facilitates interdisciplinary communication.

Processing of the precursor to the catalytic RNA subunit of RNase P from Escherichia coli

M1 RNA, the catalytic subunit of RNase P from Escherichia coli, is transcribed in vivo as a precursor with extra nucleotides at the 3' end. Although it was suggested previously that RNase E is not responsible for the 3' processing of M1 RNA, we show that RNase E is the enzyme responsible for this reaction. At nonpermissive temperatures, the 3' processing of M1 RNA is abolished in a temperature-sensitive strain of E. coli that harbors a mutation in the gene for RNase E. Enhanced processing of M1 RNA is correlated with the overproduction of RNase E in vivo and processing is also correlated with the activity of this enzyme during the course of its purification. The biosynthesis of mature M1 RNA can proceed from transcripts that are produced under the control of a proximal promoter, as well as from a distal, upstream promoter. Transcription from the distal promoter results in a polycistronic transcript that includes four open reading frames and the transcript of rnpB, the gene coding for M1 RNA. The enzymatic activity that removes the 5' nucleotides from the precursor to M1 RNA is not due to RNase E, RNase P, or RNase III alone.

A clinical study of clozapine treatment and predictors of response in a Canadian sample

OBJECTIVE

To study the clinical response to clozapine in patients with refractory schizophrenia.

METHOD

Open trial of clozapine in 61 consecutively-treated patients.

RESULTS

Following clozapine, the level of function of patients was improved relative to admission (p = 0.0001) and to the highest level in the previous year (p = 0.0001). Severity of illness was decreased (p = 0.0001). Overall, 31% of the patients were classified as responders to clozapine and the responders were all identified by 32 weeks of treatment. Poor functioning in the previous year was associated with less favourable response. At a mean interval of 26 months following discharge, 72% of the patients were continuing clozapine treatment.

CONCLUSIONS

This open trial of patients who were treated consecutively indicates a comparable degree of response to clozapine as observed in controlled clinical trials, and that level of functioning in the previous year was the best predictor of response.

Inhibition of viral gene expression by the catalytic RNA subunit of RNase P from Escherichia coli

The catalytic RNA subunit (M1 RNA) of RNase P from Escherichia coli has been converted to an endoribonuclease that specifically cleaves the mRNA that encodes thymidine kinase (TK) of herpes simplex virus 1 (HSV-1). Covalent attachment to the 3' end of M1 RNA of a sequence complementary to TK mRNA results in very efficient cleavage of the target RNA in vitro. This reaction can be stimulated by proteins extracted from both E. coli and HeLa cells. When mouse cells in culture that express the novel RNA construct are infected with HSV-1, the levels of both TK mRNA and protein are reduced by approximately 80% as compared with cells that either do not express the novel RNA construct or express constructs with certain deletions that are known to abolish the catalytic activity of M1 RNA.

Scoping out 1995. How experts see the health care year unfolding. Interview by Terese Hudson

In this issue, we look at the business side of health care from two different vantage points. First, how will health care fare in 1995 in the context of the overall economy? We've gathered a panel of economic experts to make predictions. Their conclusions? In general, providers won't benefit from a probable upturn in the broader economy.

Substrate recognition by human RNase P: identification of small, model substrates for the enzyme

RNase P from HeLa cells can efficiently cleave tRNA precursor molecules in vitro but cannot cleave potential substrates from which the D, anticodon and variable loops and stems of the tRNA moiety have all been removed. However, molecules from which the latter subdomains have been removed individually do serve as substrates. We show here that molecules that contain only a 5' leader sequence, the acceptor stem and the T stem and loop of the tRNA domain, and a bulge as small as one nucleotide downstream from nucleotide 7 in the tRNA sequence at the junction of the two stems, can serve as substrates for human RNase P. The identity of the nucleotide in the bulge is important in determining both the efficiency of the cleavage and the conformation of the substrate and/or the enzyme-substrate complex. We also show that the human enzyme locates the appropriate site for cleavage of its substrates in part by 'measuring' the length of the helices in the acceptor and T stems in both model and natural substrates.

Obstetric complications and severity of illness in schizophrenia

A history of obstetric complications (OCs) is common in schizophrenia and may lead to a severe form of the disorder. In order to test this possibility, three questions were identified: (1) Is a history of OCs in schizophrenia common in patients with a severe form of illness? (2) Do patients with OCs have more impaired function, greater severity of illness, and poorer treatment outcome than those with no identified OCs? (3) Are OCs associated with an early age at onset of illness? Obstetric history, clinical indices of functioning, and illness severity were obtained for 83 severely ill patients with schizophrenia. The proportion of patients with a history of OCs was greater in this study than has been reported previously. Subjects with a history of OCs had better functioning than those with no OCs at the time of admission but no group differences were found at discharge. No difference in age at onset of illness was found between patients with and without an OC history.

Diagnostic reassessment and treatment response in schizophrenia

BACKGROUND

The reasons for poor treatment response in some patients with schizophrenia remain unclear. It is possible that misdiagnosis of nonschizophrenic disorders as schizophrenia could result in suboptimal pharmacotherapy in some patients.

METHOD

To assess this possibility, 110 severely ill, chronic patients with a referral diagnosis of schizophrenia were comprehensively assessed and rediagnosed according to DSM-III-R criteria. Global Assessment of Function (GAF) and Clinical Global Impressions (CGI) ratings were made at admission and at discharge from the ward, after the implementation of individualized treatment plans.

RESULTS

The diagnosis of schizophrenia was confirmed in 80 patients (73%) and revised to another type of psychotic illness in 30 patients (27%). The GAF and CGI ratings were similar at admission in patients with confirmed and revised diagnoses. All patients improved by the time of discharge (p = .0001); however, patients with a revised diagnosis improved more than those with confirmed schizophrenia (p = .02). Patients with a revised diagnosis were less likely to require continued hospitalization on chronic care wards (p = .004). At admission, medication regimens were similar in the two groups of patients. At discharge, patients with a revised diagnosis were less likely to have received neuroleptics (p = .007) and more likely to have received antimanic drugs (p = .0002) or electroconvulsive therapy (p = .0004).

CONCLUSION

These findings from a clinical sample suggest that diagnostic reassessment is an important first step in the management of apparently refractory schizophrenia.

Differential evolution of substrates for an RNA enzyme in the presence and absence of its protein cofactor

Selection of substrates for an RNA enzyme, the catalytic subunit of RNAase P from E. coli, has been carried out by simulation of evolution in vitro in the presence and absence of the protein cofactor of the enzyme. In the presence of the protein, substrates resembling precursor tRNAs, which were readily cleaved by the catalytic RNA, were selected in addition to others, with different sequences and structures (one of which resembled the precursor to 4.5S RNA) that were not readily cleaved by the catalytic RNA alone. The ribonucleoprotein enzyme is more versatile than the RNA enzyme, and our results suggest that it and 4.5S RNA may have evolved after ancestral tRNAs.

Three-dimensional working model of M1 RNA, the catalytic RNA subunit of ribonuclease P from Escherichia coli

A three-dimensional model of M1 RNA, the catalytic RNA subunit of RNase P from Escherichia coli, was constructed with the aid of a computer. The modeling process took into account data from chemical and enzymatic protection experiments, phylogenetic analysis, studies of the activities of mutants, and the kinetics of reactions catalyzed by the binding of substrate to M1 RNA. The model provides a plausible picture of the binding to M1 RNA of the tRNA domain of a precursor tRNA substrate. The scissile bond and adjacent segments of the aminoacyl acceptor stem of a precursor tRNA substrate can fit into a cleft that leads to the phylogenetically conserved, central part of the structure.

Selection of guide sequences that direct efficient cleavage of mRNA by human ribonuclease P

Any RNA, when in a complex with another oligoribonucleotide known as an external guide sequence (EGS), can become a substrate for ribonuclease P. Simulation of evolution in vitro was used to select EGSs that bind tightly to a target substrate messenger RNA and that increase the efficiency of cleavage of the target by human ribonuclease P to a level equal to that achieved with natural substrates. The most efficient EGSs form transfer RNA precursor-like structures with the target RNA, in which the analog of the anticodon stem has been disrupted, an indication that selection for the optimal substrate for ribonuclease P yields an RNA structure different from that of present-day transfer RNA precursors.

Kinetic and thermodynamic analysis of RNA-protein interactions in the RNase P holoenzyme from Escherichia coli

A gel retardation assay has been used to examine the kinetic and equilibrium properties of the interaction between C5 protein and M1 RNA in the formation of the ribonuclease P holoenzyme from Escherichia coli. The interaction is relatively insensitive to the identity of the monovalent anions present and to pH in the range 7.0-9.0, but it has a more critical requirement for specific monovalent and divalent cations: NH4+, K+, Mg2+, Ca2+, and Mn2+ all promote efficient formation of the complex. A positive delta S (+6.4 cal mol-1 deg-1) and a negative delta H (-11.3 kcal mol-1) combine to give a delta G equal to -13.3 kcal mol-1 at 37 degrees C in 0.42 M salt. The binding reaction is sensitive to the concentration of monovalent and divalent cations, with the affinity increasing with increasing ionic strength (delta log Ka/delta log [NH4+] = +2.7 +/- 0.1). The dependence of Kd on the ionic strength and the positive delta S suggests that hydrophobic and stacking interactions contribute significantly to the formation of the RNase P holoenzyme.

Gel retardation analysis of the interaction between C5 protein and M1 RNA in the formation of the ribonuclease P holoenzyme from Escherichia coli

C5 protein binds specifically and with high affinity to M1 RNA to form the ribonuclease P holoenzyme of Escherichia coli. The interactions between the two subunits of the enzyme have been studied in vitro by a gel retardation assay. The stoichiometry of the subunits in the holoenzyme is 1:1. The dissociation constant (Kd) for the specific interactions of the subunits in the holoenzyme complex is < or = 0.4 nM. C5 protein also has nonspecific affinity for M1 RNA and a variety of other RNA molecules with Kd values in the order of 10-40 nM. Scatchard analysis of binding data suggests the existence of two modes of interaction between C5 protein and M1 RNA--one high-affinity and one low-affinity mode. Regions of M1 RNA essential for formation of the specific complex with C5 protein have been defined by deletion analysis and footprinting methods. Our data show that regions of M1 RNA that interact with C5 protein are clustered into three main areas that are localized between nucleotides 41-99, 168-198, and 266-287.