Newly formed dust within the circumstellar environment of SN Ia-CSM 2018evt

Dust associated with various stellar sources in galaxies at all cosmic epochs remains a controversial topic, particularly whether supernovae play an important role in dust production. We report evidence of dust formation in the cold, dense shell behind the ejecta-circumstellar medium (CSM) interaction in the Type Ia-CSM supernova (SN) 2018evt three years after the explosion, characterized by a rise in mid-infrared emission accompanied by an accelerated decline in the optical radiation of the SN. Such a dust-formation picture is also corroborated by the concurrent evolution of the profiles of the Hα emission line. Our model suggests enhanced CSM dust concentration at increasing distances from the SN as compared to what can be expected from the density profile of the mass loss from a steady stellar wind. By the time of the last mid-infrared observations at day +1,041, a total amount of 1.2 ± 0.2 × 10-2 M⊙ of new dust has been formed by SN 2018evt, making SN 2018evt one of the most prolific dust factories among supernovae with evidence of dust formation. The unprecedented witness of the intense production procedure of dust may shed light on the perceptions of dust formation in cosmic history.

Performance demonstration of vacuum microwave components critical for the operation of the ITER low-field side reflectometer

Final design studies in preparation for manufacturing have been performed for functional components of the vacuum portion of the ITER Low-Field Side Reflectometer (LFSR). These components consist of an antenna array, electron cyclotron heating (ECH) protection mirrors, phase calibration mirrors, and vacuum windows. Evaluation of these components was conducted at the LFSR test facility and DIII-D. The antenna array consists of six corrugated-waveguide antennas for simultaneous profile, fluctuation, and Doppler measurements. A diffraction grating, incorporated into the plasma-facing miter bend, provides protection of sensitive components from stray ECH at 170 GHz. For in situ phase calibration of the LFSR profile reflectometer, an embossed mirror is incorporated into the adjacent miter bend. Measurements of the radiated beam profile indicate that these components have a small, acceptable effect on mode conversion and beam quality. Baseline transmission characteristics of the dual-disk vacuum window are obtained and are used to guide ongoing developments. Preliminary simulations indicate that a surface-relief structure on the window surfaces can greatly improve transmission. The workability of real-time phase measurements was demonstrated on the DIII-D profile reflectometer. The new automated real-time analysis agrees well with the standard post-processing routine.

In vivo modulation of polo-like kinases supports a key role for PLK2 in Ser129 α-synuclein phosphorylation in mouse brain

α-Synuclein is the major component of Lewy bodies. α-Synuclein phosphorylated at Ser 129 (Phospho-α-Syn) is the most common synuclein modification observed in Parkinson's disease pathology and transgenic animal models. Polo-like kinase 2 (PLK2) was previously proposed as an important kinase in α-synuclein phosphorylation at Ser129. To better understand the role of PLK2 in α-synuclein phosphorylation in vivo, we further evaluated the effect of PLK2 genetic knockdown and pharmacological inhibition on Phospho-α-Syn levels in different brain regions of PLK2 knockout (KO), heterozygous (Het) and wild-type (WT) mice. Whereas PLK2 knockdown had no effect on Total-α-synuclein brain levels, it resulted in a gene-dosage dependent, albeit incomplete, reduction of endogenous Phospho-α-Syn levels in all brain regions investigated. No compensatory induction of other α-synuclein kinases (PLK3, casein kinase-2, G-protein-coupled receptor kinase 5 (GRK5) and GRK6) was observed at the mRNA level in the PLK2 KO mouse brain. To determine whether increased activity of another PLK family member is responsible for the residual Phospho-α-Syn levels in the PLK2 KO mouse brain, the pan-PLK inhibitor BI 2536 was tested in PLK2 KO mice. Whereas BI 2536 reduced Phospho-α-Syn levels in WT mice, it did not further reduce the residual endogenous Phospho-α-Syn levels in PLK2 KO and Het mice, suggesting that a kinase other than PLK1-3 accounts for the remaining PLK inhibitor-resistant pool in the mouse brain. Moreover, PLK3 KO in mice had no effect on both Total- and Phospho-α-Syn brain levels. These results support a significant role for a PLK kinase in phosphorylating α-synuclein at Ser129 in the brain, and suggest that PLK2 is responsible for this activity under physiological conditions.

The operative correction of symptomatic flat foot deformities in children: the relationship between static alignment and dynamic loading

At our institution surgical correction of symptomatic flat foot deformities in children has been guided by a paradigm in which radiographs and pedobarography are used in the assessment of outcome following treatment. Retrospective review of children with symptomatic flat feet who had undergone surgical correction was performed to assess the outcome and establish the relationship between the static alignment and the dynamic loading of the foot. A total of 17 children (21 feet) were assessed before and after correction of soft-tissue contractures and lateral column lengthening, using standardised radiological and pedobarographic techniques for which normative data were available. We found significantly improved static segmental alignment of the foot, significantly improved mediolateral dimension foot loading, and worsened fore-aft foot loading, following surgical treatment. Only four significant associations were found between radiological measures of static segmental alignment and dynamic loading of the foot. Weakness of the plantar flexors of the ankle was a common post-operative finding. Surgeons should be judicious in the magnitude of lengthening of the plantar flexors that is undertaken and use techniques that minimise subsequent weakening of this muscle group.

Initial description of the human NLRP3 promoter

Mutations in NLRP3 (CIAS1) are identified in a continuum of related inflammatory disorders, known as cryopyrinopathies since NLRP3 codes for the protein cryopyrin. Approximately 40% of patients with classic presentation lack mutations in the coding region of NLRP3 suggesting heterogeneity or epigenetic factors. Cryopyrin is a key regulator of proinflammatory cytokine release. Therefore, variations in the NLRP3 promoter sequence may have effects on disease state in patients with cryopyrinopathies and other inflammatory diseases. In this report, we confirmed three 5'-untranslated region splice forms with two separate transcriptional start sites, and identified potential promoter regions and six new DNA promoter variants. One variant is unique to a mutation negative cryopyrinopathy patient and increases in vitro gene expression. Additional studies can now be performed to further characterize the NLRP3 promoter and sequence variants, which will lead to better understanding of the regulation of NLRP3 expression and its role in disease.

Evaluation of the validity of the Quality of Well-being Scale in Trinidad and Tobago

Both developing countries in the Caribbean and developed countries face resource allocation challenges. However, cost-effectiveness analysis instruments that may assist in allocation of resources have not been tested in Caribbean countries. Trinidad and Tobago is an advantageous location to test an instrument for potential use in the Caribbean. It has a single payer healthcare system and a literate population. Due to historical and current migration from other Caribbean countries, the population might be a fair representation of English-speaking Caribbean nations. We tested the validity of the Quality of Well-being Scale (QWB) on a sample of the non-institutionalized general population in Trinidad. The survey included reports of chronic conditions and items from the Trinidad and Tobago National Health Interview Survey. Data were analyzed using a multivariable regression model. One adult from each of 235 households consented to the interview. The results are consistent with results obtained in the United States of America. Being older female, more chronic conditions and more symptoms/problems were significantly associated with lower mean QWB scores. These results suggest that the QWB with US-derived weights show evidence of validity in Trinidad and Tobago. Thus, health decision makers can use the QWB to compare the effects of different health conditions and health interventions. In addition, investigators can make cross-cultural comparisons of QWB scores for diseases or health conditions.

Impact of Ménière's disease on quality of life

OBJECTIVE

To describe health-related quality of life among patients with Ménière's disease in whom conventional therapy failed and who requested further medical intervention.

STUDY DESIGN

Pretreatment interviews to establish baseline quality of life characteristics before medical intervention.

SETTING

Tertiary referral center.

PATIENTS

19 adult patients, 12 women and 7 men, whose ages ranged from 32 to 83 years.

INTERVENTIONS

Pretreatment baseline interviews.

MAIN OUTCOME MEASURES

Quality of Well-being Scale, SF-12 Physical and SF-12 Mental scores, Center for Epidemiologic Studies-Depression Scale.

RESULTS

The Quality of Well-being score (0.561) indicated a loss of well-being from 1 to 0.561 = 43.9% in patients with Ménière's disease as compared with people with no symptoms and full functional status. The hypothesis that Quality of Well-being scores on days on which patients had symptoms characteristic of acute Ménière's disease episodes were lower than Quality of Well-being scores on days on which they did not report such symptoms was supported (p = 0.000). The reported SF-12 Physical mean score (38.9) was greater than 1 standard deviation below the general mean of 50, and the SF-12 Mental score (44.2) was 0.5 standard deviation below the general mean of 50. The Center for Epidemiologic Studies-Depression Scale score was 23, with a score 16 or greater indicating clinically significant depression.

CONCLUSIONS

The results suggest that the condition of patients with Ménière's disease may be measured by these instruments, that the instruments are in substantial agreement about the serious impairment in patients' quality of life, and that the days with acute episodes of Ménière's disease symptoms are significantly worse than the days without such symptoms. Treating physicians indicated surprise at the breadth and the level of debilitation characteristic of these patients with Ménière's disease.

Substitution model of sequence evolution for the human immunodeficiency virus type 1 subtype B gp120 gene over the C2-V5 region

Phylogenetic analyses frequently rely on models of sequence evolution that detail nucleotide substitution rates, nucleotide frequencies, and site-to-site rate heterogeneity. These models can influence hypothesis testing and can affect the accuracy of phylogenetic inferences. Maximum likelihood methods of simultaneously constructing phylogenetic tree topologies and estimating model parameters are computationally intensive, and are not feasible for sample sizes of 25 or greater using personal computers. Techniques that initially construct a tree topology and then use this non-maximized topology to estimate ML substitution rates, however, can quickly arrive at a model of sequence evolution. The accuracy of this two-step estimation technique was tested using simulated data sets with known model parameters. The results showed that for a star-like topology, as is often seen in human immunodeficiency virus type 1 (HIV-1) subtype B sequences, a random starting topology could produce nucleotide substitution rates that were not statistically different than the true rates. Samples were isolated from 100 HIV-1 subtype B infected individuals from the United States and a 620 nt region of the env gene was sequenced for each sample. The sequence data were used to obtain a substitution model of sequence evolution specific for HIV-1 subtype B env by estimating nucleotide substitution rates and the site-to-site heterogeneity in 100 individuals from the United States. The method of estimating the model should provide users of large data sets with a way to quickly compute a model of sequence evolution, while the nucleotide substitution model we identified should prove useful in the phylogenetic analysis of HIV-1 subtype B env sequences.

The importance of gender on outcome after major trauma: functional and psychologic outcomes in women versus men

BACKGROUND

Outcome after major trauma is an increasingly important focus of injury research. The effect of gender on functional and psychological outcomes has not been examined. The Trauma Recovery Project is a large, prospective, epidemiologic study designed to examine multiple outcomes after major trauma, including quality of life, functional outcome, and psychological sequelae such as depression and early symptoms of acute stress reaction. The specific objectives of the present report are to examine gender differences in short- and long-term functional and psychological outcomes in the Trauma Recovery Project population.

METHODS

Between December 1, 1993, and September 1, 1996, 1,048 eligible trauma patients triaged to four participating trauma center hospitals in the San Diego Regionalized Trauma System were enrolled in the study. The enrollment criteria for the study included age 18 years and older, admission Glasgow Coma Scale score of 12 or greater, and length of stay greater than 24 hours. Quality of life was measured after injury using the Quality of Well-being scale, a sensitive index to the well end of the functioning continuum (range, 0 = death to 1.000 = optimum functioning). Depression was assessed using the Center for Epidemiologic Studies Depression scale and early symptoms of acute stress reaction were assessed using the Impact of Events scale. Patient outcomes were assessed at discharge and at 6, 12, and 18 months after discharge.

RESULTS

Functional outcome was significantly worse at each follow-up time point in women (n = 313) versus men (n = 735). Quality of Well-being scale scores were markedly and significantly lower at 6-month follow-up in women compared with those in men (0.606 vs. 0.646, p < 0.0001). This association persisted at 12-month (0.637 vs. 0.6685, p < 0.0001) and 18-month (0.646 vs. 0.6696, p < 0.0001) follow-up. Women were also significantly more likely to be depressed at all follow-up time points (discharge odds ratio [OR] = 1.4, p < 0.05; 6-month follow-up OR = 2.2, p < 0.01; 12-month follow-up OR = 2.0, p < 0.01; 18-month follow-up OR = 2.2, p < 0.01) and to have early symptoms of acute stress reaction at discharge (OR = 1.4, p < 0.05). These differences remained significant and independent after adjusting for injury severity, mechanism, age, and sociodemographic factors.

CONCLUSION

Women are at risk for markedly worse functional and psychological outcomes after major trauma than men, independent of injury severity and mechanism. Gender differences in short- and long-term trauma outcomes have important implications for future studies of recovery from trauma.

Functional gamma-secretase inhibitors reduce beta-amyloid peptide levels in brain

Converging lines of evidence implicate the beta-amyloid peptide (Ass) as causative in Alzheimer's disease. We describe a novel class of compounds that reduce A beta production by functionally inhibiting gamma-secretase, the activity responsible for the carboxy-terminal cleavage required for A beta production. These molecules are active in both 293 HEK cells and neuronal cultures, and exert their effect upon A beta production without affecting protein secretion, most notably in the secreted forms of the amyloid precursor protein (APP). Oral administration of one of these compounds, N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester, to mice transgenic for human APP(V717F) reduces brain levels of Ass in a dose-dependent manner within 3 h. These studies represent the first demonstration of a reduction of brain A beta in vivo. Development of such novel functional gamma-secretase inhibitors will enable a clinical examination of the A beta hypothesis that Ass peptide drives the neuropathology observed in Alzheimer's disease.

The impact of major in-hospital complications on functional outcome and quality of life after trauma

BACKGROUND

Little is known about the impact of major in-hospital complications on functional outcome in the short- and long-term period after serious injury. The Trauma Recovery Project (TRP) is a large, prospective, epidemiologic study designed to examine multiple outcomes after major trauma, including quality of life and functional limitation. Patient outcomes were assessed at discharge and at 6, 12, and 18 months after discharge. The specific objectives of the present report are to examine the effect of postinjury complications on functional outcomes at discharge and at 6-, 12-, and 18-month follow-up time points in the TRP population.

METHODS

Between December 1, 1993, and September 1, 1996, 1,048 eligible trauma patients triaged to four participating trauma center hospitals in the San Diego Regionalized Trauma System were enrolled in the study. The enrollment criteria for the study included age 18 years or older; admission Glasgow Coma Scale score of 12 or greater; and length of stay greater than 24 hours. Quality of life was measured after injury using the Quality of Well-being (QWB) scale, a sensitive index to the well end of the functioning continuum (range, 0 [death] to 1.000 [optimum functioning]). Major in-hospital complications were assessed for 820 patients and were coded as pulmonary, cardiovascular, gastrointestinal, hepatic, hematologic, infections, renal, musculoskeletal, neurologic, and vascular, on the basis of standardized codes used in the Trauma Registry.

RESULTS

Major in-hospital complications were present in 83 (10.1%) patients. Discharge QWB scores were significantly lower in patients with major complications (0.394 vs. 0.402, p < 0.05). QWB scores were also significantly lower at 6-month follow-up in patients with major complications (0.575 vs. 0.637, p < 0.0001). Types of major complications with significantly lower 6-month follow-up QWB scores were pulmonary, gastrointestinal, infections, and musculoskeletal. Patients with major complications also had significantly lower 12-month (0.626 vs. 0.674, p < 0.01) and 18-month (0.646 vs. 0.681, p < 0.05) follow-up QWB scores. Pulmonary major complications and infections were associated with significantly lower QWB scores at 12-month follow-up.

CONCLUSION

These results provide new evidence that major in-hospital complications may have an important impact on functional outcomes after major trauma.

Likelihood-based tests of topologies in phylogenetics

Likelihood-based statistical tests of competing evolutionary hypotheses (tree topologies) have been available for approximately a decade. By far the most commonly used is the Kishino-Hasegawa test. However, the assumptions that have to be made to ensure the validity of the Kishino-Hasegawa test place important restrictions on its applicability. In particular, it is only valid when the topologies being compared are specified a priori. Unfortunately, this means that the Kishino-Hasegawa test may be severely biased in many cases in which it is now commonly used: for example, in any case in which one of the competing topologies has been selected for testing because it is the maximum likelihood topology for the data set at hand. We review the theory of the Kishino-Hasegawa test and contend that for the majority of popular applications this test should not be used. Previously published results from invalid applications of the Kishino-Hasegawa test should be treated extremely cautiously, and future applications should use appropriate alternative tests instead. We review such alternative tests, both nonparametric and parametric, and give two examples which illustrate the importance of our contentions.

Testing the hypothesis of a recombinant origin of human immunodeficiency virus type 1 subtype E

The human immunodeficiency virus type 1 (HIV-1) epidemic in Southeast Asia has been largely due to the emergence of clade E (HIV-1E). It has been suggested that HIV-1E is derived from a recombinant lineage of subtype A (HIV-1A) and subtype E, with multiple breakpoints along the E genome. We obtained complete genome sequences of clade E viruses from Thailand (93TH057 and 93TH065) and from the Central African Republic (90CF11697 and 90CF4071), increasing the total number of HIV-1E complete genome sequences available to seven. Phylogenetic analysis of complete genomes showed that subtypes A and E are themselves monophyletic, although together they also form a larger monophyletic group. The apparent phylogenetic incongruence at different regions of the genome that was previously taken as evidence of recombination is shown to be not statistically significant. Furthermore, simulations indicate that bootscanning and pairwise distance results, previously used as evidence for recombination, can be misleading, particularly when there are differences in substitution or evolutionary rates across the genomes of different subtypes. Taken jointly, our analyses suggest that there is inadequate support for the hypothesis that subtype E variants are derived from a recombinant lineage. In contrast, many other HIV strains claimed to have a recombinant origin, including viruses for which only a single parental strain was employed for analysis, do indeed satisfy the statistical criteria we propose. Thus, while intersubtype recombinant HIV strains are indeed circulating, the criteria for assigning a recombinant origin to viral structures should include statistical testing of alternative hypotheses to avoid inappropriate assignments that would obscure the true evolutionary properties of these viruses.

Coordinated plant defense responses in Arabidopsis revealed by microarray analysis

Disease resistance is associated with a plant defense response that involves an integrated set of signal transduction pathways. Changes in the expression patterns of 2,375 selected genes were examined simultaneously by cDNA microarray analysis in Arabidopsis thaliana after inoculation with an incompatible fungal pathogen Alternaria brassicicola or treatment with the defense-related signaling molecules salicylic acid (SA), methyl jasmonate (MJ), or ethylene. Substantial changes (up- and down-regulation) in the steady-state abundance of 705 mRNAs were observed in response to one or more of the treatments, including known and putative defense-related genes and 106 genes with no previously described function or homology. In leaf tissue inoculated with A. brassicicola, the abundance of 168 mRNAs was increased more than 2.5-fold, whereas that of 39 mRNAs was reduced. Similarly, the abundance of 192, 221, and 55 mRNAs was highly (>2.5-fold) increased after treatment with SA, MJ, and ethylene, respectively. Data analysis revealed a surprising level of coordinated defense responses, including 169 mRNAs regulated by multiple treatments/defense pathways. The largest number of genes coinduced (one of four induced genes) and corepressed was found after treatments with SA and MJ. In addition, 50% of the genes induced by ethylene treatment were also induced by MJ treatment. These results indicated the existence of a substantial network of regulatory interactions and coordination occurring during plant defense among the different defense signaling pathways, notably between the salicylate and jasmonate pathways that were previously thought to act in an antagonistic fashion.

Purification and cloning of amyloid precursor protein beta-secretase from human brain

Proteolytic processing of the amyloid precursor protein (APP) generates amyloid beta (Abeta) peptide, which is thought to be causal for the pathology and subsequent cognitive decline in Alzheimer's disease. Cleavage by beta-secretase at the amino terminus of the Abeta peptide sequence, between residues 671 and 672 of APP, leads to the generation and extracellular release of beta-cleaved soluble APP, and a corresponding cell-associated carboxy-terminal fragment. Cleavage of the C-terminal fragment by gamma-secretase(s) leads to the formation of Abeta. The pathogenic mutation K670M671-->N670L671 at the beta-secretase cleavage site in APP, which was discovered in a Swedish family with familial Alzheimer's disease, leads to increased beta-secretase cleavage of the mutant substrate. Here we describe a membrane-bound enzyme activity that cleaves full-length APP at the beta-secretase cleavage site, and find it to be the predominant beta-cleavage activity in human brain. We have purified this enzyme activity to homogeneity from human brain using a new substrate analogue inhibitor of the enzyme activity, and show that the purified enzyme has all the properties predicted for beta-secretase. Cloning and expression of the enzyme reveals that human brain beta-secretase is a new membrane-bound aspartic proteinase.

Covariation of physical and mental symptoms across illnesses: results of a factor analytic study

OBJECTIVE

Chronic illnesses are associated with reports of symptoms, problems, and dysfunction along multiple dimensions. To determine if the dimensionality is disease-specific and whether physical and emotional symptoms are concomitant and inseparable aspects of the illness experience, we present a factor analysis of symptom and problem reports from five different chronic conditions.

METHOD

People with five different conditions participated in this study: multiple sclerosis (MS) (n = 263), non-insulin-dependent diabetes mellitus (n = 420), nonhead nonneck injury trauma (n = 852), and a group of terminal patients comprised of acquired immune deficiency syndrome (AIDS) (n = 99) and cancer (n = 74) patients. Participants were asked to complete the Quality of Well-Being Scale (QWB) and symptom items from the QWB were factor analyzed.

RESULTS

Both within each condition and across conditions, two factors accounted for the majority of the explained variance and could be described as an Observable Limitations factor and a Subjective Symptoms factor.

CONCLUSIONS

Our factor analyses suggest that physical and emotional symptoms covary and are common to different types of illness.

FVB/N (H2(q)) mouse is resistant to arthritis induction and exhibits a genomic deletion of T-cell receptor V beta gene segments

Animal models of autoimmune diseases have been instrumental in advancing our understanding of autoimmunity in humans. Collagen-induced arthritis (CIA) in mice is an autoimmune disease model of rheumatoid arthritis. Susceptibility to CIA in mice is linked to genes of the major histocompatibility complex (MHC). CD4(+) T cells that express the T-cell receptor (TCR) Tcra-V11.1 and/or Tcrb-V8.2 play a key role in the pathogenesis of arthritis in the DBA/1 mouse (H2(q)). We identified an inbred mouse strain, FVB/NJ (H2(q)), that is resistant to arthritis induction and exhibits a genomic deletion of certain Tcrb-V gene segments. We report a novel polymerase chain reaction-based method for the rapid identification of new mouse strains that exhibit germline Tcrb-V gene deletions. We mapped for the first time both the 5' and 3' breakpoints of the Tcrb-V deletion in the FVB/NJ, SWR, SJL, C57L, and C57BR strains to within 1.1 kilobases. Since there is an association between a particular Tcra-V allele (Tcra-V11.1(d)) and arthritis susceptibility in H2(q) mouse strains, we examined the allelic polymorphisms of the Tcra-V11 gene subfamily members between the arthritis-susceptible DBA/1 mouse and the arthritis-resistant FVB/NJ mouse strain. The amino acid sequences of the Tcra-V11.1 alleles differ at two positions (codons 18 and 68). Therefore, the resistance of FVB/NJ mouse to arthritis induction may be due in part to Tcra-V11.1 coding sequence polymorphism and Tcrb-V8.2 gene segment deletion, as we have recently demonstrated in the case of SWR mouse strain.

T-cell receptor vbeta deletion and valpha polymorphism are responsible for the resistance of SWR mouse to arthritis induction

Collagen type II-induced arthritis (CIA) develops in susceptible mouse strains after intradermal injections of type II collagen (CII) in complete Freund's adjuvant (CFA). Susceptibility to CIA in mice is linked to genes of the major histocompatibility complex (MHC). Although the SWR mouse has a susceptible MHC haplotype (H2q), it is resistant to CIA. SWR exhibits at least two known immunological defects: (1) it contains a germline deletion of about 50% of T-cell receptor (TCR) Vbeta-chain gene segments, and (2) SWR is deficient in complement component C5. It has been shown that T cells that express TCRValpha11.1 and TCRVbeta8.2 play a substantial role in the pathogenesis of arthritis in the DBA/1 mouse (H2q). We generated SWR transgenic (tg) mice to determine whether the expression of pathogenic Valpha11.1 and/or Vbeta8.2 transgenes would confer arthritis susceptibility. Arthritis was induced in the SWR TCRalphabeta tg mice, but not in SWR TCRbeta tg mice. To address the role of Valpha11.1 in arthritis susceptibility, we examined the allelic polymorphisms of the Tcra-V11-gene subfamily members between the arthritis susceptible DBA/1 mouse and the arthritis-resistant SWR mouse strain. The amino acid sequences of the Valpha11.1 alleles differ at two positions (codons 18 and 68). Accordingly, these two amino acid changes are sufficient to allow the production of pathogenic T cells in SWR mice. This is the first demonstration of the association of a particular Tcra-V allele and arthritis susceptibility in mice.

Outcome after major trauma: 12-month and 18-month follow-up results from the Trauma Recovery Project

BACKGROUND

The importance of outcome after major injury has continued to gain attention in light of the ongoing development of sophisticated trauma care systems in the United States. The Trauma Recovery Project (TRP) is a large prospective epidemiologic study designed to examine multiple outcomes after major trauma in adults aged 18 years and older, including quality of life, functional outcome, and psychologic sequelae such as depression and posttraumatic stress disorder (PTSD). Patient outcomes were assessed at discharge and at 6, 12, and 18 months after discharge. The specific objectives of the present report are to describe functional outcomes at the 12-month and 18-month follow-ups in the TRP population and to examine the association of putative risk factors with functional outcome.

METHODS

Between December 1, 1993, and September 1, 1996, 1,048 eligible trauma patients triaged to four participating trauma center hospitals in the San Diego Regionalized Trauma System were enrolled in the TRP study. The admission criteria for patients were as follows: (1) age 18 years or older; (2) Glasgow Coma Scale score on admission of 12 or greater; and (3) length of stay greater than 24 hours. Functional outcome after trauma was measured before and after injury using the Quality of Well-Being (QWB) Scale, an index sensitive to the well end of the functioning continuum (0 = death, 1.000 = optimum functioning). Follow-up at 12 months after discharge was completed for 806 patients (79%), and follow-up at 18 months was completed for 780 patients (74%). Follow-up contact at any of the study time points (6, 12, or 18 months) was achieved for 926 (88%) patients.

RESULTS

The mean age was 36 +/- 14.8 years, and 70% of the patients were male; 52% were white, 30% were Hispanic, and 18% were black or other. Less than 40% of study participants were married or living together. The mean Injury Severity Score was 13 +/- 8.5, with 85% blunt injuries and a mean length of stay of 7 +/- 9.2 days. QWB scores before injury reflected the norm for a healthy adult population (mean, 0.810 +/- 0.171). At the 12-month follow-up, there were very high levels of functional limitation (QWB mean score, 0.670 +/- 0.137). Only 18% of patients followed at 12 months had scores above 0.800, the norm for a healthy population. There was no improvement in functional limitation at the 18-month follow-up (QWB mean score, 0.678 +/- 0.130). The majority of patients (80%) at the 18-month follow-up continued to have QWB scores below the healthy norm of 0.800. Postinjury depression, PTSD, serious extremity injury, and intensive care unit days were significant independent predictors of 12-month and 18-month QWB outcome.

CONCLUSION

This study demonstrates a prolonged and profound level of functional limitation after major trauma at 12-month and 18-month follow-up. This is the first report of long-term outcome based on the QWB Scale, a standardized quality-of-life measure, and provides new and provocative evidence that the magnitude of dysfunction after major injury has been underestimated. Postinjury depression, PTSD, serious extremity injury, and intensive care unit days are significantly associated with 12-month and 18-month QWB outcome.

Familial antiphospholipid antibody syndrome: criteria for disease and evidence for autosomal dominant inheritance

OBJECTIVE

To develop diagnostic criteria for a familial form of antiphospholipid antibody syndrome (APS), identify families with >1 affected member, examine possible modes of inheritance, and determine linkage to potential candidate genes.

METHODS

Family members of probands with primary APS were analyzed for clinical and laboratory abnormalities associated with APS. Families with > or =2 affected members were analyzed by segregation analysis and typed for candidate genetic markers.

RESULTS

Seven families were identified. Thirty of 101 family members met diagnostic criteria for APS. Segregation studies rejected both environmental and autosomal recessive models, and the data were best fit by either a dominant or codominant model. Linkage analysis showed independent segregation of APS and several candidate genes.

CONCLUSION

Clinical and laboratory criteria are essential to identify the spectrum of disease associated with APS. We believe a set of criteria was developed that can precisely define affected family members with APS. Modeling studies utilizing these criteria strongly support a genetic basis for disease in families with APS and suggest that a susceptibility gene is inherited in an autosomal dominant pattern. However, in these families, APS was not linked with HLA, Fas, or other candidate genes, including beta2-glycoprotein 1, HLA, T cell receptor beta chain, Ig heavy chain, antithrombin III, Fas ligand, factor V, complement factor H, IgK, and Fas.

The Quality of Well-Being Scale: critical similarities and differences with SF-36

PURPOSE

To summarize the development and application of a generic measure of health-related quality of life known as the Quality of Well-Being Scale (QWB).

BACKGROUND

The QWB is part of a general health policy model. The measure includes functional components for mobility, physical activity, and social activity. In addition, it includes a comprehensive list of symptoms and problems. QWB scoring allows placement of each individual on a continuum of wellness ranging from 0 (for dead) to 1.0 for asymptomatic full function. The General Health Policy Model combines this point in time measure with information on prognosis and mortality to estimate quality-adjusted life-years (QALYs). Forming a ratio of program costs to QALYs yields estimates of cost per quality-adjusted life year. Evidence supports the validity of the QWB for a wide variety of applications in population monitoring, descriptive studies of patient populations, and clinical trials. We offer a variety of comparisons between the QWB and Medical Outcomes Study Short Form 36 (SF-36).

MAIN FINDINGS

In comparison with the SF-36, the QWB provides less information on health profiles, but has the advantage of providing a metric that can be used for cost-utility or cost-effectiveness analysis. Although ceiling effects are common for some SF-36 subscales, perfect scores on the QWB are very rare. The QWB has an approximately normal distribution for populations of adults. Although, often criticized for not including a mental health component, we present evidence documenting the validity of the QWB for patients with psychological and psychiatric diagnoses.

CONCLUSIONS

The QWB and SF-36 are alternative comprehensive measures of health outcomes.

Comparison of the Quality of Well-being Scale and the SF-36 results among two samples of ill adults: AIDS and other illnesses

PURPOSE

To compare results of using the SF-36 Short Form 36 (SF-36) and the Quality of Well-being Scale (QWB) in characterizing health outcomes over time in patients having serious illnesses, including cancer and AIDS.

BACKGROUND

The SF-36 and the QWB are alternative measures of health-related quality of life. The SF-36 is a morbidity measure that features a profile of nine dimensions. The QWB is a preference-based measure that combines morbidity and mortality into a single number. However, the QWB can also be scored and used as a profile. We compare SF-36 and QWB scores with different scoring methods to assess validity and sensitivity to change over time in health outcomes for adult patients with HIV infection, cancer, and other serious illnesses.

SUBJECTS

201 adults with serious illnesses, including 99 with AIDS and 102 with cancer or other illnesses.

PROCEDURE

All subjects received both measures at baseline and at 6-month intervals thereafter, over a period of 21/2 years.

RESULTS

In the profile mode, the QWB captured outcomes that characterize the AIDS syndrome. The SF-36 differentiated between the AIDS and other illnesses patients on some scales, but without consistent direction. However, the overall QWB showed a decrease in quality of life over time for both the AIDS and other illnesses patients while the SF-36 did not. This is because many patients died and these were counted as outcomes by the QWB and as missing data by the SF-36.

CONCLUSIONS

The QWB appears to be better able to capture outcomes of serious illness over time than does the SF-36.

Outcome after major trauma: discharge and 6-month follow-up results from the Trauma Recovery Project

BACKGROUND

The study of both short-term and long-term outcomes after major trauma has become an increasingly important focus of injury research because of the improved survival rates attributable to the evolution of sophisticated trauma care systems. The Trauma Recovery Project (TRP) is a large prospective epidemiologic study designed to examine multiple outcomes after major trauma in adults aged 18 years and older, including quality of life, functional outcome, and psychologic sequelae such as depression and posttraumatic stress disorder (PTSD). Patient outcomes were assessed at discharge and at 6, 12, and 18 months after discharge. The specific objectives of the present report are to describe functional outcomes at the discharge and 6-month follow-up time points in the TRP population and to examine the association of putative risk factors with functional outcome.

METHODS

Between December 1, 1993, and September 1, 1996, 1,048 eligible trauma patients triaged to four participating trauma center hospitals in the San Diego Regionalized Trauma System were enrolled in the TRP study. The admission criteria for patients were as follows: (1) age 18 years or older, (2) Glasgow Coma Scale score on admission of 12 or greater, and (3) length of stay greater than 24 hours. Functional outcome after trauma was measured before and after injury using the Quality of Well-Being (QWB) scale, a more sensitive index to the well end of the functioning continuum (range, 0 = death to 1.000 = optimum functioning). Functional outcome was also measured using a standard activities of daily living (ADL) scale (range, 13 = full function to 47 = maximum dysfunction). Follow-up at 6 months after discharge was completed for 826 patients (79%).

RESULTS

The mean age was 36 +/- 14.8 years; 70% of the patients were male; 52% of the patients were white, 30% were Hispanic, and 18% were black or other. Less than 40% of study participants were married or living with a partner. The mean Injury Severity Score was 13 +/- 8.5, with 85% blunt injuries, and a mean length of stay of 7 +/- 9.2 days. QWB scores before injury reflected the norm for a healthy adult population (mean, 0.810 +/- 0.171). After major trauma, QWB scores at discharge showed a significant degree of functional limitation (mean, 0.401 +/- 0.045). At 6-month follow-up, QWB scores continued to show high levels of functional limitation (mean, 0.633 +/- 0.122). Limitation measured using the standard ADL scale found only moderate dysfunction at discharge (mean, 30.0 +/- 7.7) and at 6-month follow-up (mean, 15.0 +/- 4.2). Postinjury depression, PTSD, serious extremity injury, and length of stay were significant independent predictors of 6-month QWB outcome.

CONCLUSION

Postinjury functional limitation is a clinically significant complication in trauma patients at discharge and a 6-month follow-up. The QWB yields a more sensitive assessment of functional status than traditional ADL instruments. Postinjury depression, PTSD, serious extremity injury, and length of stay are significantly associated with 6-month QWB outcome.

Fine mapping of a genetic locus for Peutz-Jeghers syndrome on chromosome 19p

Peutz-Jeghers syndrome (PJS) was recently mapped in a single report to the telomeric region of chromosome 19p (A. Hemminki et al., Nat. Genet., 15: 87-90, 1997). Our studies confirm this location and provide further localization of the PJS locus. In the five families examined, there were no recombinants with the marker D19S886. The multipoint log odds score at D19S886 is 7.52, and we found no evidence for genetic heterogeneity. We also found that all carriers expressed the PJS phenotype and no noncarriers displayed PJS sequellae, indicating complete penetrance with no sporadic cases.

Reply to Roberts: cooperation is an outcome, not a mechanism

No Abstract

Quality-adjusted life years lost to arthritis: effects of gender, race,and social class

OBJECTIVE

To estimate the public health impact of self-reported arthritis in terms of Quality-Adjusted Life Years.

METHOD

The Quality of Well-being Scale (QWB) is a general measure of health-related quality of life that scores levels of wellness on a continuum between death (0.0) and optimum functioning (1.0). Values for the QWB were imputed for the National Health Interview Survey. These estimates were adjusted for mortality based on the life tables. Age-specific estimates were obtained for those reporting arthritis and compared to estimators for the population not reporting arthritis. These estimates were broken down by race (white versus nonwhite), gender and socioeconomic status.

RESULTS

The expected life years lost because of arthritis were 1.86 (95% confidence interval 1.40-2.32 years). Arthritis was reported more often among those of lower income, those living in rural areas, those of lower educational attainment, and older respondents. Men and women did not differ in rates of reporting arthritis, but men with arthritis had lower QWB scores than women with arthritis.

CONCLUSION

Arthritis has a significant public health impact.

Relaxation: mapping an uncharted world

Nine hundred and forty practitioners of massage, abbreviated progressive muscle relaxation (PMR), yoga stretching, breathing, imagery meditation, and various combination treatments described their technique experiences on an 82-item wordlist. Factor analysis yielded 10 interpretable relaxation categories: Joyful Affects and Appraisals (Joyful), Distant, Calm, Aware, Prayerful, Accepted, Untroubled, Limp, Silent, and Mystery The relaxation response and cognitive/somatic specificity models predict Calm and Limp, which account for only 5.5% of the variance of relaxation experience. Unlike much of previous relaxation research, we found important technique differences. PMR and massage are associated with Distant and Limp; yoga stretching, breathing, and meditation with Aware; meditation with Prayerful and all techniques except PMR with Joyful. Results are consistent with cognitive-behavioral relaxation theory and have implications for relaxation theory, treatment, training, assessment, and research. We close with a revised model of relaxation that posits three global dimensions; tension-relief, passive disengagement, and passive engagement.

An outcomes study of cochlear implants in deaf patients. Audiologic, economic, and quality-of-life changes

OBJECTIVES

To investigate and quantitate the changes in economic, emotional, and health-related quality of life after cochlear implantation.

SUBJECTS

Nine patients between the ages of 18 and 60 years who qualified for surgery.

METHODS

Patients underwent assessment using four socioeconomic indicator scales administered preoperatively, and at 6 months, 1 year, 2 years, 30 months, and 3 years postoperatively. All patients continued to use their cochlear implants during the 3-year follow-up period.

RESULTS

Uniform and systematic improvement in quality of life and psychologic well-being, and a steady increase in mean personal income for the group that underwent implantation, supporting the contention that cochlear implantation is a beneficial surgical procedure for profoundly deaf patients.

Validity of the Quality of Well-Being Scale for persons with human immunodeficiency virus infection. HNRC Group. HIV Neurobehavioral Research Center

To evaluate the validity of the Quality of Well-Being Scale (QWB) for studies of patients with human immunodeficiency virus (HIV) disease, 514 men were studied who were divided among four categories: Centers for Disease Control and Prevention (CDC) Group A (N = 272), CDC-B (N = 81), CDC-C (N = 47), and uninfected male controls (N = 114). The QWB and a variety of medical, neuropsychological, and biochemical measures were administered to all participants. When QWB scores were broken down by HIV group, the CDC-C group was significantly lower (.614) than the CDC-B (.679), CDC-A (.754), or control group (.801). The difference between Groups CDC-C and CDC-A was about .14 units of well-being, which suggests that individuals lose 1/7 equivalents of 1 well year of life for each year they are in Group CDC-C in comparison to the asymptomatic group (Group CDC-A). In comparison to the controls, this would equal a 1-year of life loss for each seven infected individuals. The QWB was shown to be significantly associated with CD4+ lymphocytes (p < .001), clinician ratings of neuropsychological impairment (p < .04), neurologists ratings of dysfunction (p < .001), and all subscales of the Profile of Mood States. Baseline QWB scores were significant prospective predictors of death over a median follow-up time of 30 months. Multivariate models demonstrated high covariation between predictors of QWB. It was concluded that the QWB is a significant correlate of biological, neuropsychological, neurological, psychiatric, and mortality outcomes for male HIV-infected patients.

Morphology and primary crystal structure of a silk-like protein polymer synthesized by genetically engineered Escherichia coli bacteria

The morphology and primary crystal structure of SLPF, a protein polymer produced by genetically engineered Escherichia coli bacteria, were characterized. SLPF is a segmented copolymer consisting of amino acid sequence blocks modeled on the crystalline segments of silk fibroin and the cell attachment domain of human fibronectin. Wide angle x-ray scattering (WAXS), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and molecular simulations were used to analyze the primary crystal structure of SLPF. TEM experiments conducted on SLPF droplets cast from formic acid on amorphous carbon film demonstrated that these protein films have a microstructure formed of woven sheaves. The sheaves are composed of well-defined whisker crystallites. The width of the whiskers, 11.8 +/- 2.2 nm, may be correlated to the length of the silk-like segment in SLPF as predicted by molecular simulations. WAXS data, TEM images, SAED, patterns, molecular simulations, and theoretical diffraction patterns all were consistent with the crankshaft model proposed for Silk I by Lotz and Keith.

Effects of offering advance directives on quality adjusted life expectancy and psychological well-being among ill adults

Two hundred and four patients from various clinical services at the San Diego Veterans' Administration Medical Center and the University of California, San Diego Medical Center were randomly assigned to either experimental (offered the opportunity to execute an Advance Directive regarding the level of care they wanted to receive if incapacitated) or control (no Advance Directive offered) conditions. Patients were given a baseline interview and re-interviewed at specific intervals (3 months, 6 months, 1 year and 2 years after baseline, and every 6 months thereafter). Outcome measures included the Qualitty of Well-being Scale, a measure of health status, and the General Well-being Index, a measure of psychological well-being. All differences between the health status and psychological well-being of experimental and control groups 3.5 years after the randomization were non-significant. Methodological implications of including mortality as part of the outcomes are discussed.

Functional limitation after major trauma: a more sensitive assessment using the Quality of Well-being scale--the trauma recovery pilot project

Little is known about the degree of disability and quality of life of patients after major trauma. We conducted a prospective study to examine the incidence and predictors of functional limitation (FL). Between January 1, 1990 and March 30, 1990, 61 eligible trauma patients were enrolled in the study (admission GCS score > or = 12, LOS > 24 hours). Functional limitation after trauma was measured at discharge and 3 months after discharge using the Quality of Well-being (QWB) scale, a more sensitive index to the well end of the functioning continuum (range, 0 = death to 1.000 = optimum functioning). Functional limitation was also measured using a standard ADL scale (range, 17 = full function to 41 = maximum dysfunction). Risk factors measured were injury severity, body region, depression (CES-D) scale, and social support. Follow-up was achieved in 42 patients (70%). The mean age was 30 years, 74% were male, 52% white, 41% hispanic, and 3% other. The mean ISS was 15, with 69% blunt injuries and a mean LOS of 12 days. The QWB scores improved between discharge and follow-up; discharge mean = 0.457 (+/- 0.048), follow-up mean = 0.613 (+/- 0.118), but the mean QWB score at follow-up still reflected a significant degree of functional limitation. The mean percentage of change in QWB scores was 34.5% (+/- 25.5%) with a range of -6.34% to 103.8%. The discharge mean FDS was 29 (+/- 6.2) while the follow-up FDS mean was 17 (+/- 3.8), reflecting that most patients at follow-up reported near-perfect ADL functioning.(ABSTRACT TRUNCATED AT 250 WORDS)

Binding of vascular heparan sulfate proteoglycan to Alzheimer's amyloid precursor protein is mediated in part by the N-terminal region of A4 peptide

The exact mechanisms of deposition and accumulation of amyloid in senile plaques and in blood vessels in Alzheimer's disease remain unknown. Heparan sulfate proteoglycans may play an important role in amyloid deposition in Alzheimer's disease. Previous investigations have demonstrated high affinity binding between heparan sulfate proteoglycans and the amyloid precursor, as well as with the A4 peptide. In the current studies, a specific vascular heparan sulfate proteoglycan found in senile plaques bound with high affinity to two amyloid protein precursors (APP695 and APP770). Vascular heparan sulfate proteoglycan also bound the Alzheimer's amyloid A4 peptide, and not other amyloid protein precursor regions studied, with high affinity. Both heparan sulfate glycosaminoglycan chains and chemically deglycosylated vascular heparan sulfate proteoglycan protein core bound to A4. High affinity interactions between vascular heparan sulfate proteoglycan and the A4 peptide may play a role in the process of amyloidogenesis in Alzheimer's disease, by localizing the site of deposition of A4, protecting A4 from further proteolysis, or by promoting aggregation and fibril formation.

An alternative secretase cleavage produces soluble Alzheimer amyloid precursor protein containing a potentially amyloidogenic sequence

Cell culture studies have shown that the Alzheimer amyloid precursor protein (APP) is secreted after full-length APP is cleaved by a putative secretase at the Lys16-Leu17 bond (secretase cleavage I) of the amyloid peptide sequence. Because this cleavage event is incompatible with amyloid production, it has been assumed that secreted APP cannot serve as a precursor of the amyloid depositions observed in Alzheimer's disease. Here we show that in neuronally differentiated PC12 cells and human kidney 293 cell cultures a portion of the secreted extracytoplasmic APP reacted specifically with both a monoclonal antibody recognizing amyloid protein residues Leu17-Val24 and a polyclonal antiserum directed against amyloid protein residues Ala21-Lys28. Furthermore, this APP failed to react with antisera recognizing the cytoplasmic domain of the full-length protein. These data indicate the presence of an alternative APP secretase cleavage site (secretase cleavage II), C-terminal to the predominant secretase cleavage I. Depending on the exact location of cleavage site II, potentially amyloidogenic secreted APP species may be produced.

The genesis of the senile plaque. Further evidence in support of its neuronal origin

Senile plaques are among the most conspicuous neuropathologic changes found in the brains of elderly individuals and patients with Alzheimer's disease (AD). The origin of the amyloid beta protein (A beta P) that accumulates in senile plaques continues to be highly controversial. Recently, using quantitative immunohistochemistry and computerized image analysis, we obtained evidence that at least a subset of early ("diffuse") senile plaques originate from neurons. In the current investigation, we employed monoclonal antibodies to A beta P and the same computerized methodology to examine in further detail the quantitative patterns of A beta P deposition in diffuse plaques in a population of intellectually intact elderly individuals. The presence of neurocentric concentration gradients of A beta P accumulation was confirmed in this study. Most significantly, this was the most predominant pattern of early amyloid deposition in the population studied. The highest concentration of A beta P was centered around neuronal cell bodies or their processes, and occasionally along neuronal plasma membranes. Computerized images showed patterns that can be interpreted as a pathogenetic sequence ranging from initial neurogenic concentration gradients centered around one single neuron to larger deposits (diffuse plaques) composed of several "anastomosing" gradients involving several adjacent neurons. It is proposed that the described very early deposits constitute the initial stage in the development of the senile plaque. Although this study does not fully prove that the accumulated A beta P is synthesized in the neuron or neuronal process it surrounds, the images herein presented suggest that neurons are the initial nidus of plaque formation.

Effects of offering advance directives on medical treatments and costs

OBJECTIVE

To examine the effects of advance directives on medical treatments and on patient satisfaction and well-being and to determine whether the enhancement of patient autonomy through advance directives provides a more ethically feasible approach to cost control than does the imposition of limits through rationing.

DESIGN

Randomized, controlled trial.

SETTING

University and Veterans Affairs medical center.

PATIENTS

Two hundred and four patients with life-threatening illnesses, 100 of whom died after enrollment in the study.

INTERVENTION

Patients randomly assigned to the experimental group were offered the California Durable Power of Attorney (a typical proxy-instruction directive), and patients assigned to the control group were not offered the advance directive. Hospital admissions were monitored to assure that a summary of the document was present in the active medical record at each hospitalization.

MEASUREMENTS

Cognitive function, patient satisfaction, psychological well-being, health locus of control, sense of coherence, health-related quality of life, receipt of medical treatments, and medical treatment charges.

RESULTS

No significant differences were found between advance-directive and control groups regarding psychosocial variables, health outcome variables, and medical treatments or charges. Patients offered an advance directive had an average hospital stay of 40.8 days (95% CI, 32.2 to 49.4 days), compared with an average of 33.1 days (95% CI, 26.0 to 40.2 days) for controls. Patients offered an advance directive were charged an average of $19,502 (95% CI, $13,030 to $25,974) for medical treatments in the last month of life compared with $19,700 (95% CI, $13,704 to $25,696) for controls.

CONCLUSIONS

Despite claims that public demand for longer life accounts for rising medical costs, most surveys suggest that patients are calling for less, not more, of the expensive, high-technology treatment often used in terminal phases of illness. Executing the California Durable Power of Attorney for Health Care and having a summary copy placed in the patient's medical record had no significant positive or negative effect on a patient's well-being, health status, medical treatments, or medical treatment charges.

Relationship of general advance directive instructions to specific life-sustaining treatment preferences in patients with serious illness

OBJECTIVE

To determine whether brief general instructions in a typical proxy-instruction advance directive (California Durable Power of Attorney for Health Care [DPAHC]) provide interpretable information about patient requests to limit life-saving treatments, and to determine whether patient treatment preferences are stable over time.

DESIGN

Prospective structured interviews.

SETTING

University of California, San Diego Medical Center and Veterans Affairs Medical Center, La Jolla.

PATIENTS

One hundred four patients (from a randomly chosen sample of 185) with a 5-year life expectancy of no better than 50% as judged by their physicians.

MAIN OUTCOME MEASURES

Patients completed the California DPAHC, a proxy-instruction advance directive, at entry and at 1 year. The patients also completed a questionnaire at entry, after 6 months, and after 1 year, indicating their preferences on a five-point Likert-format comparative rating scale for cardiopulmonary resuscitation, mechanical ventilation, artificial nutrition, and hospitalization for pneumonia.

RESULTS

Sixty-eight percent of the subjects executed the DPAHC. Most patients wished treatments to be limited or withheld under certain conditions of reduced quality of life. Although general instructions noted on the DPAHC and preferences regarding specific procedures were stable over the course of a year, the advance directive's general instructions were often inconsistent with, and poor predictors of, specific procedure preferences.

CONCLUSIONS

The brief general instruction component of the California DPAHC is not helpful in communicating patient wishes regarding specific life-saving procedures.

Evidence for intracellular cleavage of the Alzheimer's amyloid precursor in PC12 cells

The Alzheimer's amyloid precursor (APP) is cleaved by an unidentified enzyme (APP secretase) to produce soluble APP. Fractionation of PC12 cell homogenates in a detergent-free buffer showed the presence of the Kunitz protease inhibitor (KPI)-containing soluble APP (nexin II) in the particulate fraction. Digitonin or sodium carbonate treatment of this fraction solubilized nexin II suggesting that it is contained in the lumen of vesicles. Nexin II production was not affected by lysosomotropic agents, suggesting that APP secretase is not a lysosomal enzyme. Labelling of cell surface proteins by iodination failed to detect full-length APP on the surface of PC12 cells, suggesting that most of this protein is located intracellularly. Furthermore, pulse-chase experiments showed that nexin II is detected in cell extracts before it appears in the culture medium. Cellular nexin II was detected at zero time of chase after only 5 min of pulse labelling with 35S-sulfate, indicated that APP secretase cleavage takes place immediately after APP is sulfated. Temperature block, pulse-chase, and 35S-sulfate-labelling experiments suggested that APP is cleaved by APP secretase intracellularly in the trans-Golgi network (TGN) or in a post-Golgi compartment.

Quality of life and policy analysis in arthritis

Problems in the American health care system have stimulated interest in cost-effectiveness methodologies. However, there is little consensus on how to define a common unit of health outcome. Many measures used in policy studies consider only mortality and do not fully capture the significant impact of disease-related dysfunction. The impact of conditions, such as osteoarthritis, that have little impact on mortality rates but substantial impact on functioning and well-being may be underestimated in these analyses. In this article, we propose a measurement and policy model that is based on a theoretical conceptualization of health outcome. The model considers the impact of disease and its treatment in terms of both morbidity and mortality. The value of the model for clinical trials, population assessments, and policy analysis is reviewed. A public policy application of the model in Oregon is briefly described.

Chondroitin sulfate proteoglycan form of the Alzheimer's beta-amyloid precursor

The Alzheimer's amyloid beta protein is derived from a family of membrane glycoproteins termed amyloid precursor proteins (APP). Here we show that APP exists as the core protein of a chondroitin sulfate (CS) proteoglycan, ranging in apparent molecular size from 140 to 250 kDa, secreted by glial cell line C6. After partial purification on ion-exchange and gel chromatography, the secreted APP proteoglycan was recognized on Western blots by several antibodies specific to different regions of APP. Chondroitinase AC or ABC treatment of our samples completely eliminated the high molecular weight proteoglycan with a concomitant increase in the APP protein. This digested product reacted with an anti-stub antibody which recognizes 4-sulfated disaccharide. Sequencing of the N terminus of the core protein of this CS proteoglycan yielded 18 residues identical to the N terminus sequence of the mature APP. Quantitative analysis showed that, in this cell line, about 90% of the secreted nexin II form of APP occurs in the proteoglycan form, suggesting that the CS chains have a role in the biological function of this protein. The close proximity of two consensus CS attachment sites to both the N terminus of the amyloid beta protein and the secretase cleavage site, suggests that the CS chains may affect the proteolysis of APP and production of the amyloid beta protein.