A prognostic model predicting recovery of walking independence of elderly patients after hip-fracture surgery. An experiment in a rehabilitation unit in Northern Italy.

UNLABELLED: A score for identifying post-hip-fracture surgery patients at various levels (high, medium, and low) of risk for unsuccessful recovery of pre-fracture walking ability was developed. Three hundred ninety-eight HF patients were enrolled in the study. The score significantly and independently predicted failure to walk independently at discharge, failure to walk independently after 12 months, and death after 12 months. The score may be useful for clinicians and healthcare administrators to target populations for rehabilitative programs. INTRODUCTION: To develop a model predicting at the time that elderly hip-fracture (HF) patients undergo rehabilitation if they will have recovered walking independence at discharge. METHODS: Data from all patients admitted to a Department of Rehabilitation in Italy between January 2001 and June 2008 after HF surgery were used. Variables concerning cognitive, clinical, functional, and social parameters were evaluated. Predominant measures were identified through correspondence analysis, and a variable score was defined. Three risk classes (minimum, moderate, and high) were identified and univariate and multivariate logistic regressions were used to assess the model's predictivity and risk classes for the various outcomes. RESULTS: Three hundred ninety-eight HF patients were enrolled. The variables selected to construct the score were age, gender, body mass index, number of drugs being taken, the Mini Mental State Examination, the Instrumental Activity of Daily Living, and the pre-fracture Barthel index. According to univariate analysis, the score was not better than the pre-fracture Barthel's index, but, according to multivariate analysis, it was an independent predictor for all the outcomes, while the pre-fracture Barthel index predicted only outcomes at discharge. In particular, the score significantly predicted failure to walk independently at discharge, failure to walk independently after 12 months, and death after 12 months. CONCLUSIONS: A method of identifying post-HF surgery patients at various levels (high-, medium-, and low-) of risk for unsuccessful recovery of pre-fracture walking ability has been designed. The method may be useful for clinicians and healthcare administrators to target populations for rehabilitative programs.

PI3K/AKT signaling determines a dynamic switch between distinct KSRP functions favoring skeletal myogenesis.

Skeletal myogenesis is orchestrated by distinct regulatory signaling pathways, including PI3K/AKT, that ultimately control muscle gene expression. Recently discovered myogenic micro-RNAs (miRNAs) are deeply implicated in muscle biology. Processing of miRNAs from their primary transcripts is emerging as a major step in the control of miRNA levels and might be well suited to be regulated by extracellular signals. Here we report that the RNA binding protein KSRP is required for the correct processing of primary myogenic miRNAs upon PI3K/AKT activation in myoblasts C2C12 and in the course of injury-induced muscle regeneration, as revealed by Ksrp knock-out mice analysis. PI3K/AKT activation regulates in opposite ways two distinct KSRP functions inhibiting its ability to promote decay of myogenin mRNA and activating its ability to favor maturation of myogenic miRNAs. This dynamic regulatory switch eventually contributes to the activation of the myogenic program.

Akt2-mediated phosphorylation of Pitx2 controls Ccnd1 mRNA decay during muscle cell differentiation.

Paired-like homeodomain 2 (Pitx2), first identified as the gene responsible for the Axenfeld-Rieger syndrome, encodes a protein factor that, controlling cell proliferation in a tissue-specific manner, has a crucial role in morphogenesis. During embryonic development, Pitx2 exerts a role in the expansion of muscle progenitors and is expressed at all stages of myogenic progression. In this study, we show that Pitx2 is phosphorylated by the protein kinase Akt2 and is necessary to ensure proper C2C12 myoblast proliferation and differentiation. Pitx2 associates with a ribonucleoprotein complex that includes the mRNA stabilizing factor HuR and sustains Ccnd1 (also known as Cyclin D1) expression, thereby prolonging its mRNA half-life. When the differentiation program is initiated, phosphorylation by Akt2 impairs the ability of Pitx2 to associate with the Ccnd1 mRNA-stabilizing complex that includes HuR and, as a consequence, Ccnd1 mRNA half-life is shortened. We propose that unphosphorylated Pitx2 is required to favor HuR-mediated Ccnd1 mRNA stabilization, thus sustaining myoblast proliferation. Upon Akt2-phosphorylation, the complex Pitx2/HuR/Ccnd1 mRNA dissociates and Ccnd1 mRNA is destabilized. These events contribute to the switch of C2C12 cells from a proliferating to a differentiating phenotype.

Altered vessel signalling molecules in subjects with Downs syndrome.

Downs syndrome (DS) is the most frequent human chromosomal abnormality and is associated with mental retardation. Some evidence indicates that certain inflammatory molecules may be increased in DS. Proinflammatory and vasoactive molecules in the blood of non demented subjects with DS were measured in the present investigation. Plasma levels of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1) and C reactive protein (CRP) were measured in child (2-14 years), adult (20-50 yrs) and elderly (> 60 yrs) DS subjects. Increased plasma levels of IL-6 and MCP-1 were present in DS. Plasma levels of VEGF were increased only in DS adults. Positive linear correlation between IL-6 and MCP-1 levels was present. However, no subclinical inflammation was apparent in DS, since neopterin and CRP levels were within the normal range. An altered regulation of these molecules might interfere with some processes involved in cognitive performances of DS subjects.

The management of adverse clinical events in nursing homes: a 1-year survey study.

OBJECTIVE: In Italian nursing homes (NHs), care delivery at night and during holidays is not regulated by regional laws; some facilities employ staff physicians, others employ physicians engaged from year to year (temporary physicians), and others employ publicly funded National Health System (NHS) physicians. This study was designed to determine whether the use of different kinds of physicians leads to different outcomes with regard to the rate of hospitalization and appropriateness of the management of adverse clinical events. DESIGN: Prospective, nonrandomized-survey data collection. SETTING: Ten nonprofit nursing facilities in Italy. PARTICIPANTS: Three hundred and fifty-two NH residents, staff physicians, temporary physicians, and NHS physicians. MEASUREMENTS: Medical intervention during adverse clinical events occurring at night and during holidays. RESULTS: Three hundred and fifty-two residents experienced 551 adverse clinical events; 78 were hospitalized. The hospitalization rate of NHS physicians was about two times that of the temporary physicians and six times that of the staff physicians. Staff physicians' diagnoses and management were appropriate in the majority of cases; NHS diagnosis and management were doubtful or incorrect in about one-third of all cases. CONCLUSIONS: NH residents frequently experience adverse clinical events; physician characteristics influence the rate of hospitalization and the quality of medical interventions.

Ontogeny of pituitary adenylate cyclase-activating polypeptide (PACAP) in the frog (Rana ridibunda) tadpole brain: immunohistochemical localization and biochemical characterization.

The anatomic distribution and biochemical characteristics of the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) were investigated in the central nervous system of the frog, Rana ridibunda, during development. Three to four days after hatching, at stages IV-VII, PACAP-immunoreactive perikarya were detected in the dorsal thalamus within the anterior ventral area, and a few fibers were found in the medial pallium. Positive cell bodies were first observed in the hypothalamus at stages VIII-IX, at the level of the dorsal and ventral infundibular nuclei. In these regions, the number of positive perikarya increased during ontogeny. In tadpoles, during the mid- and late premetamorphosis, a more complex organization of the PACAP-immunoreactive system was found in the thalamus with the appearance, at stages IX-XII, of two additional groups of positive neurons in the ventrolateral area and posterocentral nucleus. At stages XIII-XVIII of larval development and subsequent larval stages, PACAP-immunoreactive fibers were found in the median eminence. In newly metamorphosed animals, several additional groups of positive perikarya appeared in the medial pallium, the preoptic nucleus, the torus semicircularis, the tegmentum of the mesencephalon, and the cerebellum. The immunoreactive peptide contained in the tadpole brain was characterized by high performance liquid chromatography analysis combined with radioimmunoassay quantification. At all stages investigated, the predominant form of PACAP-immunoreactive material coeluted with synthetic frog PACAP38. The occurrence of PACAP soon after hatching indicates that the peptide may exert neurotrophic activities. The existence of immunoreactive elements in several thalamic regions at mid- and late premetamorphic stages suggests that PACAP may act as a neurotransmitter, neuromodulator, or both, during ontogenesis. Finally, the presence of PACAP-immunoreactive perikarya in hypothalamic nuclei and nerve fibers in the median eminence supports the view that PACAP may play a role in the control of pituitary hormone secretion during larval development.

One-year mortality in elderly stable patients with COPD.

A retrospective study was performed to evaluate the risks of one-year mortality in very old hospitalized patients including those suffering from chronic obstructive pulmonary disease (COPD). Six hundred and fifty-eight disabled patients (M = 194, mean age 79.2 +/- 7.4 years) consecutively admitted to and discharged from a Geriatric Evaluation and Rehabilitation Unit (GERU) after a comprehensive rehabilitation program were studied and divided into two groups: COPD (n = 337, 51%) and non-COPD (n = 321, 49%). Multidimensional evaluation including information on demographics, cognitive status [Mini Mental State Examination (MMSE)], physical health [number of diseases, Greenfield's Individual Disease Severity (IDS), and number of drugs used], functional disability [Basic Activity of Daily Living (BADL), Tinetti scale, and Physical Performance Test (PPT)], and nutritional status [Prognostic Nutritional Index (PNI)] were assessed at admission. Survival rate was assessed over a 1-year period following discharge. COPD patients mainly differed from non-COPD in terms of older age, smoking habit, number of associated diseases and drugs used. Aggregating the IDS 2-3-4 COPD classes (symptoms + functional impairment), the risk of one-year mortality was double that of the IDS 1 COPD class (symptoms only) and of non-COPD subjects (IDS 0 class) after adjusting for age, sex, disability, malnutrition, and comorbility. Moreover, IDS 2-3-4 COPD patients suffering from cor pulmonale (CP) had a fourfold 1-year risk of mortality in comparison with the IDS 1 COPD group after adjusting for the same covariates. Hospitalized stable very old COPD patients presenting functional impairment have a higher 1-year risk of mortality than only symptomatic COPD or non-COPD subjects. The presence of cor pulmonale with COPD further increases this risk.

Presenilin 1 protein directly interacts with Bcl-2.

Presenilin proteins are involved in familial Alzheimer's disease, a neurodegenerative disorder characterized by massive death of neurons. We describe a direct interaction between presenilin 1 (PS1) and Bcl-2, a key factor in the regulation of apoptosis, by yeast two-hybrid interaction system, by co-immunoprecipitation, and by cross-linking experiments. Our data show that PS1 and Bcl-2 assemble into a macromolecular complex, and that they are released from this complex in response to an apoptotic stimulus induced by staurosporine. The results support the idea of cross-talk between these two proteins during apoptosis.

Menopause and estrogen deficiency as a risk factor in dementing illness: hypothesis on the biological basis.

The positive efficacy of estrogen replacement therapy (ERT) in the treatment of neurodegenerative disorders such as Alzheimer's disease (AD) is a matter of intense debate among clinicians and neuroscientists. The experimental and preliminary clinical evidence supporting the use of ERT are based on epidemiological data and on the study of the effect of estrogens on several aspects of brain homeostasis, including the modulation of neurotransmitters and vascular changes. In spite of numerous data available the mechanisms underlying the putative estrogen effects in neurodegenerative diseases are largely unknown. The aim of this paper is to discuss and elaborate on some of the hypotheses and controversial findings currently present in this field.

Energy metabolism inhibition impairs amyloid precursor protein secretion from Alzheimer's fibroblasts.

The present study investigates the influence of aglycemia and sodium azide (a Cytochrome c Oxidase inhibitor) on sAPP secretion from skin fibroblasts derived from sporadic AD patients and control subjects. Aglycemia reduced sAPP release in the medium of both AD and control fibroblasts to a similar extent after 2 h incubation. Treatment for 2 h with increasing azide concentrations (1 microM-100 mM) under glucose deprivation did not significantly affect sAPP secretion from control fibroblasts, but was able to significantly inhibit sAPP secretion from AD fibroblasts (maximal inhibition 51%). The failure of antioxidants like glutathione (GSH) or N-acetylcysteine (NAC) to antagonize the azide effect on AD fibroblasts and lipoperoxidation data seemed to rule out the possibility that oxidative stress could mediate the sodium azide effect on sAPP release from AD fibroblasts.

Distribution of vasoactive intestinal peptide-like immunoreactivity in the brain and pituitary of the frog (Rana esculenta) during development.

The localization of vasoactive intestinal peptide (VIP)-like immunoreactive (ir) elements was investigated in the brain of the anuran amphibian, Rana esculenta, during development. Using an antiserum raised against the porcine VIP, ir cell bodies and fibers were observed in the forebrain of tadpoles a few days after hatching. During early premetamorphosis, ir perikarya were distributed in the ventral infundibular nucleus of the hypothalamus and in the posterocentral nucleus of the thalamus. Labeled fibers were detected in the olfactory bulbs and in the hypothalamus. In these larvae, furthermore, several VIP-ir cells were found in the pars distalis of the pituitary and there were ir fibers in the pars nervosa. In tadpoles at stages VIII-IX, a new group of VIP-labeled neurons was observed in the dorsal part of the infundibular nucleus. In other brain regions, the distribution of the immunoreactivity was similar to that described in the earliest stages, i.e., IV-VII. During mid-premetamorphosis, stages X-XII of development, an additional set of ir perikarya appeared in the ventrolateral area of the thalamus. During late premetamorphosis, stages XIII-XVIII, the organization of VIP-like immunoreactivity was more complex and its distribution more widespread. Two new groups of ir cell bodies appeared, one in the preoptic nucleus and another in the anteroventral area of the thalamus, and for the first time, VIP immunoreactivity was observed in the median eminence. This distribution pattern persisted through to the prometamorphic, four-limb stage. Strikingly, no VIP-ir elements were observed anywhere in the mid- and hindbrain. The present results indicate that a VIP-like ir peptide may be involved in the processing of olfactory information or may act as a neurohormone, hypophysiotropic factor, and neuromodulator in the brain of R. esculenta during development.

Role of brain allopregnanolone in the plasticity of gamma-aminobutyric acid type A receptor in rat brain during pregnancy and after delivery.

The relation between changes in brain and plasma concentrations of neurosteroids and the function and structure of gamma-aminobutyric acid type A (GABAA) receptors in the brain during pregnancy and after delivery was investigated in rats. In contrast with plasma, where all steroids increased in parallel, the kinetics of changes in the cerebrocortical concentrations of progesterone, allopregnanolone (AP), and allotetrahydrodeoxycorticosterone (THDOC) diverged during pregnancy. Progesterone was already maximally increased between days 10 and 15, whereas AP and allotetrahydrodeoxycorticosterone peaked around day 19. The stimulatory effect of muscimol on 36Cl- uptake by cerebrocortical membrane vesicles was decreased on days 15 and 19 of pregnancy and increased 2 days after delivery. Moreover, the expression in cerebral cortex and hippocampus of the mRNA encoding for gamma2L GABAA receptor subunit decreased during pregnancy and had returned to control values 2 days after delivery. Also alpha1, alpha2, alpha3, alpha4, beta1, beta2, beta3, and gamma2S mRNAs were measured and failed to change during pregnancy. Subchronic administration of finasteride, a 5alpha-reductase inhibitor, to pregnant rats reduced the concentrations of AP more in brain than in plasma as well as prevented the decreases in both the stimulatory effect of muscimol on 36Cl- uptake and the decrease of gamma2L mRNA observed during pregnancy. These results indicate that the plasticity of GABAA receptors during pregnancy and after delivery is functionally related to fluctuations in endogenous brain concentrations of AP whose rate of synthesis/metabolism appears to differ in the brain, compared with plasma, in pregnant rats.

Specific role for protein kinase C alpha in the constitutive and regulated secretion of amyloid precursor protein in human skin fibroblasts.

Reduced levels of protein kinase C alpha (PKC alpha) seems to be related to an altered amyloid precursor protein (APP) secretion in fibroblasts from Alzheimer's disease (AD) patients. In this report we used a specific inhibitor of PKC alpha (Gö-6976), to investigate the role of PKC alpha in the basal and phorbol esters regulated secretion of soluble APP (sAPP) in human fibroblasts derived from healthy aged volunteers. Treatment with Gö-6976 alone reduced basal secretion by a maximum of 39%, compared to untreated cells, suggesting the partial dependence of constitutive APP secretory pathway on PKC alpha enzyme. Moreover Gö-6976 treatment completely abolished the effect of phorbol-esters mediated PKC stimulation on sAPP release, suggesting that PKC alpha is the only PKC isoform involved in controlling the secretion of sAPP in human fibroblasts.

Peripheral markers in testing pathophysiological hypotheses and diagnosing Alzheimer's disease.

Alterations in amyloid precursor protein (APP) metabolism, calcium regulation, oxidative metabolism, and transduction systems have been implicated in Alzheimer's disease (AD). Limitations to the use of postmortem brain for examining molecular mechanisms underscore the need to develop a human tissue model representative of the pathophysiological processes that characterize AD. The use of peripheral tissues, particularly of cultured skin fibroblasts derived from AD patients, could complement studies of autopsy samples and provide a useful tool with which to investigate such dynamic processes as signal transduction systems, ionic homeostasis, oxidative metabolism, and APP processing. Peripheral cells as well as body fluids (i.e., plasma and CSF) could also provide peripheral biological markers for the diagnosis of AD. The criteria required for a definite diagnosis of AD presently include clinical criteria in association with histopathologic evidence obtained from biopsy or autopsy. Thus, the use of peripheral markers as a diagnostic tool, either to predict or at least to confirm a diagnosis, may be of great importance.

Detection of GnRH molecular forms in brains and gonads of the crested newt, Triturus carnifex.

Gonadotrophin-releasing hormone (GnRH) immunoreactivity is detectable in the brain, ovary, and testis of the newt, Triturus carnifex, collected during February (reproductive phase), May, and July (nonreproductive phase). In the brain of May animals, chicken GnRH-II positive cell bodies are located within the terminal nerve, the anterior preoptic area, and the preoptic nucleus, which appears to be devoid of immunoreactive mammalian GnRH cell bodies. During February and July, both chicken GnRH-II and mammalian GnRH are detected only within the terminal nerve and anterior preoptic area. Generally, in the reproductive as well as the nonreproductive periods, chicken GnRH-II fibers are widely distributed in the brain; however, the distribution of fibers of both molecular forms suggests that they exert hypophysiotropic activity. High-pressure liquid chromatography (HPLC) coupled with radioimmunoassay indicates the presence of an early-eluting GnRH peak in brains and gonads but not in plasma. Using chicken GnRH-II antiserum, immunoreactivity is observed in spermatocytes, spermatozoa, and the external theca layer. Seasonal changes of the GnRH-like material are observed in both sexes, and its high concentration detectable during February is in good correlation with the timing of reproduction.

Functional impairment in protein kinase C by RACK1 (receptor for activated C kinase 1) deficiency in aged rat brain cortex.

Several laboratories have reported a lack of protein kinase C (PKC) activation in response to various stimuli in the brain of aged rats. It has been suggested that changes in lipid membrane composition could be related to this functional deficit. However, recent evidence has indicated that the translocation of PKC to the different subcellular compartments is controlled by protein-protein interactions. Recently, a class of proteins, termed receptors for activated C kinase (RACKs), have been described that bind PKC. The present study was conducted to determine whether alterations in RACK1, the best-characterized member of RACKs, were associated with changes in translocation and expression of PKC. Quantitative immunoblotting revealed that RACK1 content was decreased by approximately 50% in aged rat brain cortex, compared with that in adult and middle-aged animals. The levels of calcium-independent PKC delta and epsilon, interacting with RACK1, and related calcium-independent PKC activity were not modified by the aging process. By comparison, phorbol ester-stimulated translocation of this activity and of PKC delta and epsilon immunoreactivity was absent in cortex from aged animals, as well as the translocation of the calcium-dependent PKC beta, also known to interact with RACK1. These results indicate that a deficit in RACK1 may contribute to the functional impairment in PKC activation observed in aged rat brain.

The gain of apolipoprotein E genotyping to separate patients with Alzheimer's disease from normal individuals: relevance to community studies.

Neuropsychological screening tests such as the Mini Mental State Examination (MMSE) are commonly used for case finding in community studies on dementia or Alzheimer's disease (AD). However, the high proportion of false-positives is an important limitation to the feasibility of such studies. The aim of this study was to evaluate whether adding apoliporotein E (apoE) genotyping to the MMSE is followed by a significant reduction of the false-positive rate. Subjects were 70 AD patients (MMSE 13-28) and 70 normal controls (MMSE 25-30). Multivariable discriminant analysis was used to classify subjects on the basis of age, gender, MMSE score and the presence of the epsilon 4 allele of apoE. When sensitivity was set at 99%, the model including age, gender and MMSE had a false-positive rate of 13.5%, while adding epsilon 4 to the previous variables decreased this figure to 6.7%. In a hypothetical community study screening for AD in a population of 1,000,000, this would turn in a decrease of false-positives from about 19,000 to about 9,500. We conclude that the use of apoE genotyping in community case-finding studies is promising and should deserve further consideration.