Apoptosis in the skeletal muscle of patients with heart failure: investigation of clinical and biochemical changes

OBJECTIVE—To investigate the contribution of apoptosis in the development of the skeletal myopathy in chronic heart failure.
DESIGN—The electrophoretic pattern of myosin heavy chains (MHC), fibre cross sectional area, number of in situ nick end labelling (TUNEL) positive apoptotic myocyte nuclei, and the tissue levels of caspase-3, Bcl-2, and ubiquitin were determined in biopsies taken from the vastus lateralis muscle. The study involved nine patients with severe chronic heart failure caused by ischaemic heart disease and hibernating myocardium and five controls.
RESULTS—In chronic heart failure patients the vastus lateralis showed a significant increase of MHC_2a and MHC_2b and a greater degree of fibre atrophy, as demonstrated by the decreased cross sectional area. There was also an increased number of TUNEL positive apoptotic myocyte nuclei. Tissue concentrations of Bcl-2 were decreased, while those of caspase-3 and ubiquitin were increased. Peak oxygen consumption (VO₂) was negatively correlated with the number of TUNEL positive nuclei and the fibre cross sectional area. There was a correlation between the number of apoptotic nuclei and the fibre cross sectional area, but no correlation between myosin heavy chains and number of apoptotic nuclei.
CONCLUSIONS—Myocyte apoptosis occurs in the skeletal muscle of patients with chronic heart failure, and its magnitude is associated with the severity of exercise capacity limitation and the degree of muscle atrophy. Muscle atrophy contributes to the limitation of exercise capacity, together with the increased synthesis of fast, more fatiguable myosin heavy chains.


Keywords: apoptosis; chronic heart failure; exercise capacity; myosin heavy chains     

Bioinformatic methods for integrating whole-genome expression results into cellular networks

Extracting a comprehensive overview from the huge amount of information arising from whole-genome analyses is a significant challenge. This review critically surveys the state of the art methods that are used to connect information from functional genomic studies to biological function. Cluster analysis methods for inferring the correlation between genes are discussed, as are the methods for integrating gene expression information with existing information on biological pathways and the methods that combine cluster analysis with biological information to reconstruct novel biological networks.     

Development and validation of the ABC pain scale for healthy full-term babies

AIM: We developed and validated a pain scale (ABC scale) for term babies based on acoustic features of crying. METHODS: The scale consisted of three different cry parameters: (a) pitch of the first cry; (b) rhythmicity of the crying bout; (c) constancy of crying intensity. These parameters were previously found to distinguish between medium and high levels of pain measured by spectral analysis of crying. We validated the scale using healthy term babies undergoing routine heel prick. Concurrent validity was assessed comparing pain values obtained with our scale with those obtained with another pain scale; this relationship was also used to assess the sensitivity of the scale. To assess specificity we compared the ABC scores during a painful event (heel prick) with two non-painful events (preliminary phase of prick in the same group of babies, and heel prick with analgesia in another group). RESULTS: Specificity: (a) analgesic/non-analgesic comparison, p < 0.0001; (b) pain/sham comparison, p < 0.0001). Sensitivity: a high correlation between scores of the ABC scale and the Douleur Aigue du Nouveau-Né scale indicates good sensitivity. Concurrent validity: Spearman rho = 0.91. Internal consistency: Cronbach's alpha = 0.76. Inter-rater reliability: Cohen's kappa for multiple raters = 0.83. Intra-rater reliability: Cohen's kappa = 0.85. Practicality: All nurses who used it scored the scale as "good". CONCLUSION: The ABC scale proved to be simple and reliable for assessing pain in healthy, non-intubated term newborns.     

Better surgical prognosis for patients with complete atrioventricular septal defect and Down's syndrome

Background

Several studies have shown that Down's syndrome is not a risk factor for biventricular repair of complete atrioventricular septal defects. However, few data are available about the comprehensive outcome of all the cardiac surgical procedures in patients with trisomy 21, including palliative surgery.

Methods

This is a retrospective study of 206 consecutive patients who underwent cardiac surgery from January 1992 to January 2002. Data about mortality and morbidity were analyzed and the impact of Down's syndrome was evaluated.

Results

Overall mortality was 7.7%. Actuarial survival was 94% among patients with Down's syndrome versus 86% of the group with normal karyotype (p = 0.12). The presence of unbalanced ventricles was the only independent risk factor affecting survival at multivariate analysis (p < 0.0001). The need for a Norwood type surgery was more frequent among non-Down patients (12.0% vs 1.5%, p = 0.02) as was the prevalence of pulmonary artery banding operations (22.9% vs 9.3%, p = 0.04). Cumulative mortality after palliation was higher in non-Down patients (44% vs 2.9%, p = 0.0001). Freedom from reoperation was lower in the group with normal chromosomes in respect to patients with Down's syndrome (81.4% vs 94.6%, p = 0.04), due to the higher prevalence of anomalies of the mitral valve (4.9% vs 1.8%, p = 0.03) or left ventricular outflow tract (7.3% vs 0%, p = 0.01).

Conclusions

Down patients showed a decreased risk for biventricular repair and lower mortality and morbidity in cases of complex cardiac malformations requiring complex palliative operations.     

A pilot study of nurse-led, home-based telecardiology for patients with chronic heart failure

We assessed the feasibility of home-based telecardiology for patients with chronic heart failure (CHF). Seventy-four CHF patients were enrolled into a programme of telephone follow-up and single-lead electrocardiography (ECG) monitoring. The patients transmitted their ECG data by fixed telephone line to a receiving station, where a nurse was available for an interactive teleconsultation. Patients were followed up for a mean (SD) of 307 (108) days; 1467 calls were analysed (213 ad hoc consultations and 1254 scheduled consultations). A total of 124 cardiovascular events were recorded. Modifications to therapy were suggested in response to 119 calls; hospital admissions were suggested for 13 patients, further investigations for 7 and a consultation with the patient's general practitioner for 13. No action was taken after 1330 calls. Twenty-two ECG abnormalities were recorded. In 63 patients receiving the beta-blocker carvedilol, the mean dosage increased from 36 to 42 mg. In the previous year there were 1.8 hospitalizations per patient, while in the follow-up period there were 0.2 hospitalizations per patient. Following up CHF patients using a nurse-led telecardiology programme seems to be feasible and useful.     

Presynaptic nigro-striatal function in a group of Alzheimer’s disease patients with parkinsonism: evidence from a dopamine transporter imaging study

Summary. The occurrence of parkinsonism in Alzheimers disease (AD) is quite common, however the molecular and neurochemical changes underlying such extrapyramidal features in AD have been not fully understood. Post-mortem as well as in vivo imaging study have produced conflicting results as regards the existence of dopaminergic changes in AD. Aim of the present study was to investigate in vivo the nigro-striatal dopaminergic function in a group of AD patients with parkinsonism. Thirteen patients with AD and extrapyramidal features not related to past neuroleptic use (AD-P) underwent SPECT with ¹²³I-FP-CIT, a ligand of dopamine transporter, and the data were compared with those obtained in 15 patients with Diffuse Lewy Body Dementia (DLBD), 20 patients with Parkinsons disease (PD), and 8 healthy elderly controls. The analysis of the data was performed by regions-of-interest approach and calculations of the striatal-to-non specific (occipital lobes) radioactivity ratios were made. The ¹²³I-FP-CIT striatal uptake in patients with AD-P was similar to that obtained in the control population. Both the DLBD and PD groups showed significantly lower ¹²³I-FP-CIT uptake in all striatal areas with respect to AD-P and control groups (p<0.005). The lack of dopamine transporter changes in our series of AD-P patients can indicate that dopaminergic presynaptic function is preserved in this population and that different dopaminergic changes such as postsynaptic ones, or different neurotransmitter alterations might underlie the extrapyramidal features in AD.     

Posterior knee pain: primary symptom of a small non-occlusive venous clot

A healthy 9 year old girl presented with severe posterior knee pain and a small segmental non-occlusive popliteal venous thrombosis. The case is relevant for its unique presentation and symptoms. Lack of recanalisation persisted at one year follow up.     

Retrovirus-mediated gene transfer and galactocerebrosidase uptake into twitcher glial cells results in appropriate localization and phenotype correction

Galactocerebrosidase (GALC) is deficient in all tissues from human patients and animal models with globoid cell leukodystrophy (GLD) or Krabbe disease. The deficiency results in decreased lysosomal catabolism of certain galactolipids including galactosylceramide and psychosine that are synthesized maximally during myelination. According to current theories, the accumulation of psychosine in humans and animals with GLD induces oligodendrocyte degeneration and myelination ceases. Transduction of oligodendrocytes from twitcher mice with a retroviral vector containing the GALC cDNA can correct the enzyme deficiency in these cells. Our data show that twitcher astrocytes and oligodendrocytes can internalize exogenous GALC, as well as donate the enzyme to the mutant glial cells. Antibodies against human GALC localized the GALC antigen in retrovirally transduced cells and cells receiving enzyme via cell to cell secretion and uptake to the lysosomal fraction. In fact immunocytochemical studies in transduced oligodendrocytes revealed that the GALC colocalizes in vesicles lysosomal-associated membrane protein-2 (LAMP2) (+). Moreover, labeling cells with anti-GALC and a marker for oligodendrocytes demonstrated that, upon differentiation, transduced, twitcher oligodendrocytes attained the normal branched process configuration, while untransduced cells show only abnormal morphology. Phenotype correction in mutant oligodendrocytes has also been observed after enzyme transfer. These studies indicate that GALC activity supplied to cultured oligodendrocytes from twitcher mice by different methods can correct the pathological phenotype of these cells.     

Role of growth hormone in chronic heart failure. Therapeutic implications

Congestive heart failure is a multiple aetiology, high prevalence, poor prognosis cardiovascular disorder. Medical treatment of dilated cardiomyopathy is aimed at alleviating the symptoms of heart failure. Diuretics, ACE inhibitors and very recently, beta-blockers have been shown to have favourable effects on symptoms, exercise capacity and mortality. Growth hormone (GH) and insulin-like growth factor (IGF)-1 are involved in several physiological processes such as the control of muscle mass and function, body composition and regulation of nutrient metabolism. The roles of GH and IGF-1 as modulators of myocardial structure and function are well established. Receptors for both GH and IGF-1 are expressed by cardiac myocytes; therefore, GH may act directly on the heart or via the induction of local or systemic IGF-1, whereas IGF-1 may act by endocrine, paracrine or autocrine mechanisms. Patients with acromegaly have an increased propensity to develop ventricular hypertrophy and cardiovascular diseases and, in addition, an impaired cardiac efficiency is observed in patients with GH deficiency. Animal models of pressure and volume overload have demonstrated up-regulation of cardiac IGF-1 production and expression of GH and IGF-1 receptors, implying that the local regulation of these factors is influenced by haemodynamic changes. Moreover, experimental studies suggest that GH and IGF-1 have stimulatory effects on myocardial contractility, possibly mediated by changes in intracellular calcium handling. Heart failure is caused by ventricular dilatation with abnormal wall thickening, which leads to impaired cardiac performance; therefore, based on the evidence available for GH we would expect beneficial effects from the use of GH in these patients. Several papers highlight the positive influence of GH in the regulation of heart development and performance. In patients with GH deficiency, GH administration dramatically improves cardiac function. In small nonblind studies, both short and long term GH treatment have demonstrated beneficial effects in patients with heart failure secondary to ischaemic or idiophatic cardiomyopathy. Recently, two randomised, placebo-controlled studies, did not show significant GH-mediated improvement in cardiac performance in patients with dilated cardiomyopathy, despite significant increases in IGF-1. Acquired GH resistance, might be an important feature of severe heart failure and explain the different responses to GH therapy seen in different patients. Whether GH treatment will finally find a place, and with which modalities, in the treatment of heart failure remains to be established.