Restoration of thymocyte development and function in zap-70-/- mice by the Syk protein tyrosine kinase

The Syk family of protein tyrosine kinases, consisting of ZAP-70 and Syk, associate with the pre- and alphabeta T cell antigen receptors (TCRs) and undergo tyrosine phosphorylation and activation following receptor engagement. Thymocyte development in zap-70-/- mice is blocked at the CD4+CD8+ TCR(lo) stage. The presence of Syk in the thymus has raised the possibility that Syk may be able to mediate TCR function. To determine if Syk can play a role in thymocyte development, we generated zap-70-/- mice expressing a human syk cDNA. Syk expression restored both thymocyte development and function. In addition, Syk function required the CD45 transmembrane protein tyrosine phosphatase. Hence, ZAP-70 and Syk can play overlapping functions and exhibit similar regulatory mechanisms in mediating alphabeta T cell development.

A dose-intensive, cyclophosphamide-based regimen for the treatment of recurrent/progressive or advanced solid tumors of childhood: a report from the Australia and New Zealand Children's Cancer Study Group

BACKGROUND

Children with solid tumors that progress or recur after conventional multimodality therapies have a very poor prognosis. In a pilot study, vincristine, etoposide, and dose-escalated cyclophosphamide (VETOPEC) was shown to be a promising salvage regimen. Continued accrual of patients and increased duration of follow-up has resulted in substantial experience with VETOPEC.

METHODS

Between May 1991 and March 1994, 56 pediatric patients from 6 centers were enrolled in this study; 44 had recurrent or progressive tumors (Group A) and 12 had newly diagnosed, advanced tumors with a very poor prognosis (Group B). The VETOPEC regimen was comprised of vincristine, 0.05 mg/kg, on Days 1 and 14; etoposide, 2.5 mg/kg, on Days 1, 2, and 3; and fractionated, dose-escalated cyclophosphamide on Days 1, 2, and 3. The initial cyclophosphamide dose was 90 mg/kg (2.7 g/m2)/cycle with an escalation of 15 mg/kg/cycle in each subsequent cycle, to a maximum (over 6 cycles) of 165 mg/kg (5.0 g/m2)/cycle. Tumor response was evaluated every two to three cycles and included central review of imaging.

RESULTS

The combined and partial response rates for Groups A and B were 66% (25 of 38 patients) and 91% (10 of 11 patients), respectively. In Group A, best evaluable responses and event free (EF) survivors were observed with: brain tumors (7 of 9 patients; 2 EF at 39 and 45 months [mos], respectively), Wilms' tumor (6 of 7 patients; 3 EF at 37-49 mos), and lymphoma (4 of 4 patients; 2 EF at 52 and 59 mos, respectively); in Group B best evaluable responses and EF were observed with: neuroblastoma (5 of 6 patients; 1 disease free at 57 mos) and rhabdomyosarcoma (4 of 4 patients; no survivors). Hematologic toxicity was limiting despite support with myeloid growth factors in 33 patients. Four deaths in Group A and one in Group B were directly associated with this toxicity. Specifically, no cases of drug-related myocardial toxicity or pneumonitis were observed.

CONCLUSIONS

This chemotherapy regimen with its intense scheduling produced a high response rate and appreciable survival in patients with a variety of recurrent, progressive, or advanced solid tumors of childhood.

Granulocyte-macrophage colony-stimulating factor in association with high-dose chemotherapy (VETOPEC) for childhood solid tumors: a report from the Australia and New Zealand Children's Cancer Study Group

PURPOSE

Combination chemotherapy with vincristine, etoposide, and high-dose, escalating cyclophosphamide (VETOPEC) is an effective regimen in pediatric patients with high-risk solid tumors. The toxicity of the regimen is predominantly haematologic. This study addressed the role of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) following each cycle of chemotherapy in decreasing neutropaenia, incidence of fever/ hospitalization, and/or increasing chemotherapy dose-intensity.

PATIENTS AND METHODS

Twenty-nine children with recurrent solid tumors were treated with the VETOPEC regimen. Sequential cohorts of patients received no GM-CSF (Group I), or GM-CSF in a dosage of 5 micrograms/kg/day (Group II) or 10 micrograms/kg/day (Group III) on days 4-18 of each chemotherapy cycle. Up to four cycles of chemotherapy were analysed with respect to haematopoietic recovery, clinical parameters, and dose intensity.

RESULTS

Neutrophil recovery was significantly more rapid in patients treated with GM-CSF. Time to achieving an absolute neutrophil count (ANC) over 0.5 x 10(9)/L in Groups I, II, and III were 21, 18, and 16 days, respectively (P < 0.0001). Time to achieving an absolute neutrophil count (ANC) over 1.0 x 10(9)/L in Groups I, II, and III were 24, 19, and 17 days, respectively (P < 0.0001). There was no significant difference in the incidence of febrile neutropaenia between the three groups. Febrile neutropaenia occurred following 42, 68, and 62% of chemotherapy cycles in Groups I, II, and III, respectively (P = 0.27). Chemotherapy dose intensity was not different between the three groups. GM-CSF was associated with pericarditis and myalgias in one patient, and transient hypoxia/hypotension in another.

CONCLUSION

GM-CSF led to significantly more rapid neutrophil recovery following VETOPEC chemotherapy, but did not lead to any demonstrable clinical benefit, either in reducing febrile events, or in increasing chemotherapy dose intensity.

Delivery of oligoribonucleotides to human hepatoma cells using cationic lipid particles conjugated to ferric protoporphyrin IX (heme)

The receptor-ligand interaction between hepatocyte heme receptors and heme was evaluated as a basis for developing a targeted cationic lipid delivery reagent for nucleic acids. Heme (ferric protoporphyrin IX) was conjugated to the aminolipid dioleoyl phosphatidylethanolamine (DOPE) and used to form cationic lipid particles with dioleoyl trimethylammonium propane (DOTAP). These lipids particles (DDH) protect oligoribonucleotides from degradation in human serum and increase oligoribonucleotide uptake into 2.2.15 human hepatoma cells (to a level of 50-60 ng oligo/10(4) cells) when compared with the same lipid particles (DD) prepared identically without heme. The DDH heme level that was optimal for oligoribonucleotide delivery was also optimal for maximum expression of plasmid-encoded luciferase. The enhancing effect of heme was evident only at net particle negative charge. Fluorescence microscopy showed that DDH delivered oligoribonucleotides into both the 2.2.15 cell cytoplasm and nucleus. DDH may thus be a potentially useful delivery vehicle for oligonucleotide-based therapeutics and transgenes, appropriate for use in such liver diseases as viral hepatitis, hepatoma, and hypercholesterolemia.

CD45 regulates Src family member kinase activity associated with macrophage integrin-mediated adhesion

BACKGROUND

Adhesion of leukocytes to the extracellular matrix and to other cells is mediated by members of the integrin family of adhesion molecules. Src family kinases are activated upon integrin-mediated adhesion. In lymphocytes, CD45 is a leukocyte-specific transmembrane protein tyrosine phosphatase that activates Src family kinases associated with B-cell and T-cell antigen receptor signaling by constitutive dephosphorylation of the inhibitory carboxy-terminal tyrosine phosphorylation site. Here, we show that CD45 is also important in downregulating the kinase activity of Src family members during integrin-mediated adhesion in macrophages.

RESULTS

We found that CD45 colocalized with beta2 integrin and the Src family kinase p53/56(lyn) to adhesion sites in bone marrow-derived macrophages. Macrophages from CD45(-/-) mice were unable to maintain integrin-mediated adhesion. In adherent macrophages, absence of CD45 led to the hyperphosphorylation and hyperactivation of p56/59(hck) and p53/56(lyn), but not of p58(c-fgr). CD45 directly inactivated p59(hck) but not p56(lck) in transient transfection assays. Furthermore, coexpression of CD45 with p59(hck) or p56(lyn) containing a tyrosine to phenylalanine mutation at the carboxy-terminal negative regulatory site resulted in decreased tyrosine phosphorylation of the Src family member kinases due to dephosphorylation of the potentiating tyrosine phosphorylation site within the kinase domain.

CONCLUSIONS

Using primary bone marrow macrophages, these studies demonstrate that CD45 regulates Src family kinases and is required to maintain macrophage adhesion. CD45 decreases Src family kinase activity by dephosphorylating the tyrosine residue located within the kinase domain.

Docetaxel in combination with fluorouracil: study design and preliminary results

The relatively recent introduction of a new class of chemotherapeutic agents--the taxoids--has raised hope of improved survival for patients with advanced or metastatic cancer. Following encouraging preclinical results of taxoid combinations, this phase I, nonrandomized trial was designed to evaluate a 1-hour intravenous infusion of docetaxel (Taxotere) on day 1 combined with fluorouracil (5-FU) as a daily intravenous bolus for 5 consecutive days. To date, 27 patients with advanced solid neoplasms have received 86 courses of docetaxel/5-FU at the following dose levels: 25/100, 35/150, 50/200, 60/200, and 60/300 mg/m2. Preliminary results showed no unexpected toxicities, and the principal toxicity was neutropenia of short duration. A treatment regimen of 60 mg/m2 docetaxel on day 1 and 300 mg/m2 of 5-FU given for 5 days, with a single course length of 28 days, is projected as the maximum tolerated dose.

Symptom severity and cognitive impairment in chronically hospitalised geriatric patients with affective disorders

BACKGROUND

Affective disorders typically have a better outcome than schizophrenia, although recent evidence suggests that some patients with affective disorder have a relatively poor outcome, with cognitive impairments and persistent symptomatology.

METHOD

Fifty chronically hospitalised geriatric patients with mood disorders (major depression or bipolar disorder) were compared on the clinical symptoms and aspects of cognitive impairment with 308 geriatric schizophrenic patients who were hospitalised at the same institution. The two samples did not differ in current age or in premorbid education level, but the affective patients had a later age of onset and more females in the sample.

RESULTS

There were no overall differences in cognitive functioning between the groups, although the clinical symptom profiles resembled those seen in better outcome patients.

CONCLUSIONS

Cognitive impairment is present in poor-outcome patients with affective disorders as well as schizophrenia, suggesting that cognitive impairments predict poor outcome across psychiatric disorders and not just in schizophrenia.

Cognitive performance and mood after a weekend on call in a surgical unit

BACKGROUND

Considerable interest and concern have been expressed about junior doctors' hours. This study was carried out to evaluate the emotional and cognitive effects of a weekend on call in a surgical ward.

METHODS

Ten surgical house officers were assessed, in counterbalanced design, on four Monday mornings, twice after a weekend off duty and twice after a weekend on call. Cognitive functioning was assessed using the Cognitive Drug Research computerized cognitive assessment system, and emotional state was evaluated by means of the Aberdeen Mood Rating Scale.

RESULTS

Following a weekend on call, significant impairment in concentration, speed and power was observed, and the doctors felt less confident, less energetic and more confused. Impaired attention, working memory, long-term memory and confusion were most closely correlated with number of hours worked on Sunday, and tiredness and confusion were related to number of hours slept.

CONCLUSION

A weekend on call has significant deleterious effects on cognitive performance and mood. The findings have implications for staffing levels and the design of duty rosters.

Characteristics of elderly psychiatric patients retained in a state hospital during downsizing: a prospective study with replication

OBJECTIVE

This study examined the clinical characteristics of elderly inpatients associated with retention in a large state hospital during a period of rapid reduction in the inpatient census.

DESIGN

During the first year of the study all inpatients age 65 or greater were individually evaluated. Patients remaining in the hospital during the second year were reevaluated and followed for an additional year. Separate statistical analysis of the data allowed for replication of findings.

SETTING

The study was conducted at Pilgrim Psychiatric Center, the largest state hospital in New York State.

PARTICIPANTS

The entire inpatient population over the age of 65 were included in the study (N = 806). The average age of the sample was 76 years and 70% were assigned a lifetime research diagnosis of schizophrenia. The majority of patients were hospitalized for long periods (mean = 33.9 years) and had significant cognitive impairment.

MAIN OUTCOME MEASURES

Cognitive functioning was assessed on the Clinical Dementia Rating Scale. Severity of psychiatric symptoms was evaluated on the PANSS. Occurrence of dangerous behavior and medical and psychiatric treatment were obtained from the patients' medical histories.

MAIN RESULTS

The findings, replicated across assessments, were that patients retained had more severe symptoms of excitement, hostility and impulsive behavior than those discharged, while uncooperativeness, delusions, grandiosity and suspiciousness were also more severe in those retained than those discharged.

CONCLUSIONS

Elderly patients who are very difficult to place are so characterized because of behavior disorders that are difficult to manage rather than psychotic symptoms, cognitive impairment or medical disorders.

Determination of the true metabolizable energy (TMEN) by roosters of feedstuffs made from seal by-products

TMEN values for various seal by-product feedstuffs were determined using roosters. Four samples of seal meal [seal meal 1991, seal meal 1992, seal meal 1994 (juveniles), seal meal 1994 (mixed ages)] and three samples of seal meat (oven-dried at 50 °C, oven-dried at 120 °C, and freeze-dried) were given to 16 roosters (30 g: precision fed) housed in individual wire cages. Total collection of excreta from a 48-h period was used to provide samples for analysis of gross energy, nitrogen, and dry matter content. TMEN results indicate variability in quality of the meals, associated with the different raw materials used to produce the seal meals as well as year of production. The TMEN values for the seal meals ranged from 3896 kcal kg−1 to 4621 kcal kg−1 with an average value of 4283 kcal kg−1. The crude protein content of the seal meals ranged from 64.2 to 67.6%, the crude fat content from 12.7 to 14.7%, the calcium content from 5.38 to 8.98% and the total phosphorus content from 3.16 to 4.79%. Oven-drying the seal meat at 120 °C significantly reduced TMEN (2643 kcal kg–1). The TMEN values for the freeze-dried and the low temperature oven-dried (50 °C) seal meat were not significantly different (4008 kcal kg–1 and 4013 kcal kg–1, respectively). Key words: True metabolizable energy, seal by-products, roosters, seal meal, seal meat, TMEN

External quality assessment of the serum bactericidal test: results of a methodology/interpretation questionnaire

Two hundred microbiology laboratories in the UK took part in two separate experimental external quality assessment distributions related to the serum bactericidal test (SBT). In the first, Staphylococcus aureus NCTC 6571 (vancomycin MIC 1 mg/L), was tested against a human serum containing vancomycin 38 mg/L plus gentamicin 0.5 mg/L. In the second, Streptococcus oralis PAJ 112/4183 (penicillin MBC < or = 0.03 mg/L) and Streptococcus sanguis PAJ 107/4184 (penicillin MBC = 128 mg/L) were tested against human serum containing penicillin 15 mg/L. Respondents returned their laboratory results and a questionnaire on clinical interpretation and technical aspects. Most laboratories (194/199, 97.5%) recommend the use of the SBT in the management of infective endocarditis but only 48 (25.2%) often or always change therapy on the basis of the result. A wide range of interpretative criteria, definitions of bactericidal endpoints and methodologies are used. Performance in the first distribution was acceptable for 75% of laboratories but in the second only 34% could identify penicillin tolerance; 34 respondents reported an SBT result of < or = 2 for the tolerant strain, 81 laboratories reported one of > or = 16. Technical factors related to acceptable performance were: sonication of broth before counting the inoculum; knowing the inoculum size in cfu/mL; use of a 4-8 h broth culture to make the inoculum; incubation of recovery plates for > 36 h; use of a calibrated pipette to sample for surviving bacteria; use of measured volumes to add the inoculum. Use of uncalibrated pipettes or standard loops to recover survivors was related to poor performance. Microbiology departments in the UK should review the clinical need to perform the SBT in the light of their local circumstances and if they elect to continue to offer this test, revise their methodologies which could be producing misleading results when testing alpha-haemolytic streptococci.

Age-related differences in formal thought disorder in chronically hospitalized schizophrenic patients: a cross-sectional study across nine decades

OBJECTIVE

This study used a cross-sectional design to examine the frequency of occurrence and severity of 10 different signs of thought disorder in schizophrenic patients across the lifespan.

METHOD

Schizophrenic patients, who ranged in age from 19 to 96 years (N = 392), were examined with the Scale for Assessment of Thought, Language, and Communication. The cognitive functioning of the geriatric patients (patients over the age of 64, N = 120) was also assessed.

RESULTS

Poverty of speech was more common and more severe in geriatric patients, while four different signs of thought disorder that reflect disconnected speech were less common and less severe in geriatric patients. Analysis of covariance found that the lower severity of disconnection thought disorders in the older patients was not attributable to differences in the amount of speech produced.

CONCLUSIONS

Aspects of disconnected speech were less severe in older patients, while the severity and frequency of poverty of speech were greater. These findings suggest that the two previously identified separate dimensions of communication disorder in schizophrenia vary differently with age and possibly in their cognitive and biological underpinnings.

Empirical assessment of the factorial structure of clinical symptoms in schizophrenia. A multisite, multimodel evaluation of the factorial structure of the Positive and Negative Syndrome Scale. The PANSS Study Group

The Positive and Negative Syndrome Scale (PANSS) is widely used as a method for the assessment of symptoms of schizophrenia but the most complete model of how symptoms are structured has not been determined. Using the methods of confirmatory factor analysis with a large sample of 1,233 of schizophrenic subjects this study examined the goodness of fit of 20 previously proposed models. None of these proposed models met criteria for adequate fit to the empirical data. The sample was then stratified and half of the data was used to calibrate a new model. The model was validated in the second half of the data. The new pentagonal model uses 25 of the 30 items of the PANSS in 5 factors: positive, negative, dysphoric mood, activation, and and autistic preoccupation. Patients who varied widely in age, severity, and chronicity of illness did not differ in their overall symptom structure. The results of this study also implicated some problems in the validity of the PANSS as currently configured when used to assess symptoms of schizophrenia.

Social-Adaptive Functioning Evaluation (SAFE): a rating scale for geriatric psychiatric patients

Geriatric chronic psychiatric inpatients often remain in a chronic psychiatric hospital because of serious deficits in adaptive life functions. Because the additional complications and adaptive changes associated with aging have not been considered in previous scales, the Social-Adaptive Functioning Evaluation (SAFE) was developed. The items in the scale measure social-interpersonal, instrumental, and life skills functioning and are designed to be rated by observation, caregiver contact, and interaction with the subject if possible. Interrater and test-retest reliability were examined (n = 60) and convergent and discriminant validity were rated against other relevant measures (n = 50) in separate studies, with all being found adequate. The factor structure of the scale was examined with exploratory factor analysis, revealing a three-factor structure. Finally, predictive validity was examined in a preliminary study of 140 patients, 45 of whom were discharged after the assessment. The results indicate that patients who remained hospitalized could be discriminated from those who were sent to nursing homes or community care on the basis of certain SAFE items and subscales. These results support the use of this instrument in later studies of geriatric psychiatric patients.

Alzheimer's disease: the evolution of a diagnosis

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Cognitive impairment and negative symptoms in geriatric chronic schizophrenic patients: a follow-up study

Cognitive impairment is increasingly recognized as an important aspect of schizophrenia. Since cognitive impairment has many features in common with the negative symptoms of the illness, it is possible that some of the characteristics attributed to negative symptoms are due to an association with cognitive impairments. In order to test this hypothesis, 174 chronically hospitalized geriatric schizophrenic patients were examined twice at a 1-year follow-up with ratings of the severity of their symptoms (using the Positive and Negative Syndrome Scale: PANSS) and assessments of cognitive functions with the Mini-Mental State Examination and a brief neuropsychological battery aimed at the typical impairments seen in dementia. Positive symptoms were unassociated with any of the cognitive variables, while negative symptom severity was correlated with each of the cognitive measures. In the cross-temporal analyses, cognitive impairments were more stable over time than negative symptom scores, but cognitive impairment did not predict the severity of any negative symptom over time. At each assessment, however, cognitive impairment was strongly correlated with each of the seven negative symptoms studied. These data indicate that cognitive impairments and negative symptoms are related, but discriminable, features in schizophrenia and that the considerable overlap between some negative symptoms and estimates of cognitive function may suggest a rethinking of the definition of some of these symptoms.

Empirical evaluation of the factorial structure of clinical symptoms in schizophrenia: effects of typical neuroleptics on the brief psychiatric rating scale

There has been little investigation of the effect of neuroleptic medication on the structure of symptoms in schizophrenia. In this study, 135 male schizophrenic patients were rated with the Brief Psychiatric Rating Scale (BPRS) after 4 weeks of treatment with typical neuroleptic medication and after 2 weeks free of neuroleptics, with the order of assessment varying across patients. Confirmatory factor analyses (CFA) found that there were no differences in symptom structure across medication status and no differences in the structure of symptoms in treatment responders and nonresponders. The typical 5-factor BPRS model fit the data poorly and the fit improved considerably through deletion of items measuring symptoms not associated with schizophrenia, suggesting that some of the symptoms that contribute to a total BPRS score may be adding primarily error variance. Although the sample size in this study is limited, the results suggest that using total BPRS scores to measure severity of schizophrenic symptoms should be reconsidered.

Prevalence of dementia in older Japanese-American men in Hawaii: The Honolulu-Asia Aging Study

OBJECTIVE

To determine prevalence of dementia and its subtypes in Japanese-American men and compare these findings with rates reported for populations in Japan and elsewhere.

DESIGN AND SETTING

The Honolulu Heart Program is a prospective population-based study of cardiovascular disease established in 1965. Prevalence estimates were computed from cases identified at the 1991 to 1993 examination. Cognitive performance was assessed using standardized methods, instruments, and diagnostic criteria.

PARTICIPANTS

Subjects were 3734 Japanese-American men (80% of surviving cohort) aged 71 through 93 years, living in the community or in institutions.

MAIN OUTCOME MEASURES

Age-specific, age-standardized, and cohort prevalence estimates were computed for dementia (all cause) defined by 2 sets of diagnostic criteria and 4 levels of severity. Prevalence levels for Alzheimer disease and vascular dementia were also estimated.

RESULTS

Dementia prevalence by Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised ranged from 2.1% in men aged 71 through 74 years to 33.4% in men aged 85 through 93 years. Age-standardized prevalence was 7.6%. Prevalence estimates for the cohort were 9.3% for dementia (all cause), 5.4% for Alzheimer disease (primary or contributing), and 4.2% for vascular dementia (primary or contributing). More than 1 possible cause was found in 26% of cases. The Alzheimer disease/vascular dementia ratio was 1.5 for cases attributed primarily to Alzheimer disease or vascular dementia.

CONCLUSIONS

Prevalence of Alzheimer disease in older Japanese-American men in Hawaii appears to be higher than in Japan but similar to European-ancestry populations. Prevalence of vascular dementia appears to be slightly lower than in Japan, but higher than in European-ancestry populations. Further cross-national research with emphasis on standardized diagnostic methods is needed.

Age disorientation in chronically hospitalized patients with mood disorders

Age disorientation was studied in 45 geriatric patients with chronic mood disorders. In a yearly assessment of cognitive functions, subjects were questioned about their age, year of birth, and the current year. Patients who misstated their age by > or = 5 years were considered age disoriented. Among the 45 patients, age-disorientation data were available for 32 patients, with the remainder either stating that they did not know their age or providing age-delusional responses. Six of the 32 patients were characterized as age disoriented at baseline and again at 12- to 18-month follow-up assessment. Age-disoriented patients performed worse overall on the Mini-Mental State Examination compared with patients who did not show age disorientation. Future studies of brain function and structure should include poor-outcome patients with mood disorders as well as patients with schizophrenia in attempts to identify the possible neurological dysfunctions that may underlie the phenomenon of age disorientation.

Symptom stability in geriatric chronic schizophrenic inpatients: a one-year follow-up study

The results of previous studies of symptom stability in schizophrenia suggest that negative symptoms manifest traitlike characteristics while positive symptoms fluctuate over time. Various prospective studies of chronic schizophrenic patients have found consistent results, regardless of the follow-up period, yet there is little research addressing symptomatology in geriatric schizophrenic patients. Since these patients have a very poor outcome and more severe negative symptoms, their symptoms might differ from younger patients. This study examined the course of symptomatology in 178 geriatric schizophrenic inpatients who were assessed twice at a 1-year interval with the Positive and Negative Syndrome Scale (PANSS). Intraclass correlations revealed that the distribution of negative symptoms was considerably more stable than that of positive symptoms over the interval, and subtypes based on negative symptoms were the only ones that manifested consistent stability over time. There was also a significant increase in negative symptom severity for the sample, with a slight decrease in positive symptom severity. Thus, even in chronic inpatients, with a very extended illness, positive symptom severity is not particularly stable within patients. These data indicate that the characteristics of negative and positive schizophrenic symptoms are similar in younger and geriatric schizophrenic patients, suggesting a continuity of the illness process. Tentative evidence for increasing severity of negative symptoms over a brief follow-up period suggests the possibility of a steady worsening of clinical state in very elderly patients who remained hospitalized.