A practical approach to cardiac imaging in adults with Duchenne muscular dystrophy - echocardiography or cardiac MRI?

Funding Acknowledgements

Type of funding sources: None.

Background

The incidence of cardiomyopathy in Duchenne muscular dystrophy (DMD) increases with age, accounting for up to 20% of mortality in the third decade of life. As patients are frequently asymptomatic until advanced stages of disease, imaging plays an essential role in screening for cardiac involvement and monitoring progression. Guidelines recommend annual transthoracic echocardiography assessment, with periodic use of cardiac magnetic resonance imaging (CMR). However, some studies suggest that CMR should be the gold standard imaging in DMD. This study aimed to review the use echo and CMR in adult patients with DMD, with particular focus on practical utility and real-world limitations.

Methods

 

A retrospective chart review of 24 patients attending our DMD cardiomyopathy clinic was undertaken. Demographic data including age, genotyping and medical therapy were noted. Results of cardiac imaging, as well as discussions regarding referral for CMR were recorded.

Results

All patients had echocardiography performed in our facility (table 1) and all had a documented discussion regarding referral for CMR in their medical notes. 15 patients (60%) were unsuitable for CMR and were not referred. Reasons were inability to lie flat due to breathing/claustrophobia (n = 12) and difficulty with positioning due to contractures (n = 9). 2 patients (8%) attended for CMR but were unable to proceed due to difficulty with positioning in the scanner. 4 patients (16.5%) had CMR performed, 3 additional patients were referred and awaited CMR. Results outlined in table 1 and image 1 show correlation between measurement of left ventricular ejection fraction (LVEF) on echo and CMR. Wall motion abnormalities and fibrosis were better detected with CMR. 

Conclusion

 

Significant limitations were seen with both imaging techniques. Accessibility of CMR for adults with DMD is poor, related primarily to the severity of underlying musculoskeletal and respiratory disease. Echocardiography is easily accessible, but images are frequently suboptimal. Despite this, strong correlation was seen in assessment of LV function in those who underwent both echocardiography and CMR, with indication that echocardiography can accurately guide intensification of medications and cardiac device therapy. CMR remains the optimal modality for the assessment of myocardial fibrosis. Improving accessibility of CMR for patients with DMD should be prioritised for the future of this modality.

The effect of different feed delivery methods on time to consume feed and the resulting changes in postprandial metabolite concentrations in horses

Management techniques that reduce the insulin response to feeding in horses have application in preventing insulin resistance (IR) and potential associations (e.g., laminitis). Eight mature idle horses of BCS between 5 and 6.5 and with no previous indication of IR were fed a meal of concentrate under 4 feed delivery treatments in a repeated Latin Square design. Treatments were all based on a bucket of equal dimensions. The treatments included a control (CON) and 3 treatments hypothesized to increase time to consume feed (TCF): mobile obstacles above the feed (BALL), stationary obstacles below the feed (WAFF), and feed with water added (WTR). Jugular venous blood samples were taken at feed delivery, every 10 min for the first hour, and then every 30 min until 300 min after feed delivery. The TCF was different across treatment and was greater (P < 0.05) for BALL and WAFF when compared with CON and WTR. Glucose and insulin concentrations increased after feeding (P < 0.05) and tended to differ among treatments (P < 0.10). Peak insulin and glucose concentrations were affected by treatment as were the time to peak insulin and the area under the curve of insulin (P < 0.05). Therefore, feed delivery methods that include obstacles effectively increase TCF and attenuate postprandial glucose and insulin concentrations. A second experiment was designed to determine if the TCF changes associated with BALL and WAFF in Exp. 1 remain effective over a 4-d period. Four horses with no recent or regular history of consuming concentrates were fed concentrate meals for 4 consecutive d using the same treatments described in Exp. 1 and a Latin square design. Horses were subject to a 4-d adaptation period and were randomly assigned to 4-d treatment periods using the 4 previously described treatments. During adaptation, TCF decreased over time (P = 0.02). After adaptation, WAFF had greater TCF when compared with CON and WTR (P < 0.05) whereas WTR had the lowest TCF overall. Using obstacles to increase TCF on a daily basis may be an effective method to reduce postprandial glucose and insulin concentrations, thereby decreasing the risk of IR development in horses.

Predictions for positive nodes in breast cancer using computerized modeling

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Background: The accuracy and consistency of sentinel lymph node (SLN) biopsy for axillary staging in breast cancer has been well established by multiple studies. Although the standard of care has been to perform a completion axillary lymph node dissection (ALND) on patients who have a positive sentinel node, recent data (ACOSG Z0010, Z0011 and NSABP B-32) suggests that an ALND may be avoided in certain subsets of patients. To further study this question, we used a Bayesian model to predict the probability of finding disease in the ALND for breast cancer.

Methods: All SLN procedures performed by a single surgeon, for clinical T1-T2 N0 disease between September 2000 and March 2009 were retrospectively reviewed under an IRB approved protocol. Demographic, disease and surgical procedural variables were collected. Values are reported as mean ± standard deviation. A Bayesian model, a standard statistical model frequently used in medicine, was used to identify variables that could predict a positive ALND.

Results: A total number of 235 SLN procedures were reviewed. The mean patient age was 58.6 ± 11.8 (range 28-88), tumor size was 1.8 ± 1.3 cm (range 0.2-7.4), and BMI was 28 ± 6.1. The number of SLN found was 3.6 ± 1.9 (range 0-10), and in 2 cases no SLN were found, for an overall failure rate of 0.85%. A total of 73 ALND were performed in this group; 27 cases had ALND as national study participants randomized to ALND, 44 cases for positive SLN, and 2 cases in which no SLN could be identified. The mean number of axillary lymph nodes removed was 14.8 ± 7 and the mean number of positive axillary nodes was 2.7 ± 4.1. Tumor size, tumor grade, number of positive SLN by hematoxylin and eosin staining, and a low technetium count of the first SLN were found to be significant predictors of positive axillary nodes during a completion ALND. There was also a trend for progesterone receptor expression as a predictor of axillary disease.

Conclusions: A model to predict a positive ALND for breast cancer is presented. We found tumor characteristics, number of positive SLN and low technetium count for first SLN to be predictors for finding axillary disease. Further studies are needed to validate our model as a means of sparing women an ALND who have a low probability of finding additional breast disease.

Reduced AMP-activated protein kinase activity in mouse skeletal muscle does not exacerbate the development of insulin resistance with obesity

AIMS/HYPOTHESIS

Obesity-related insulin resistance is associated with accumulation of bioactive lipids in skeletal muscle. The AMP-activated protein kinase (AMPK) regulates lipid oxidation in muscle by inhibiting acetyl-CoA carboxylase-2 (ACC2) and increasing mitochondrial biogenesis. We investigated whether reduced levels of muscle AMPK promote lipid accumulation and insulin resistance during high-fat feeding.

METHODS

Male C57/BL6 wild-type mice and transgenic littermates overexpressing an alpha2AMPK kinase-dead (KD) in muscle were fed control or high-fat diet. Whole-body glucose homeostasis was assessed by glucose and insulin tolerance tests, and by measuring fasting and fed serum insulin and glucose. Insulin action in muscle was determined by measuring 2-deoxy-[(3)H]glucose uptake and Akt phosphorylation in incubated soleus and extensor digitorum longus muscles. Muscle triacylglycerol, diacylglycerol and ceramide content was measured by thin-layer chromatography. Mitochondrial proteins were measured by immunoblotting.

RESULTS

KD mice had reduced skeletal muscle alpha2AMPK activity (50% in gastrocnemius and >80% in soleus and extensor digitorum longus) and ACC2 Ser228 phosphorylation (90% in gastrocnemius). High-fat feeding increased body mass and adiposity, and impaired insulin and glucose tolerance; however, there were no differences between wild-type and KD littermates. High-fat feeding impaired insulin-stimulated muscle glucose uptake and Akt-phosphorylation, while increasing muscle triacylglycerol, diacylglycerol (p = 0.07) and ceramide, but these effects were not exacerbated in KD mice. In response to high-fat feeding, mitochondrial proteins were increased to similar levels in wild-type and KD muscles.

CONCLUSIONS/INTERPRETATION

Obesity-induced lipid accumulation and insulin resistance were not exacerbated in AMPK KD mice, suggesting that reduced levels of muscle alpha2AMPK do not promote insulin resistance in the early phase of obesity-related diabetes.

Cannabinoid activation of PPAR alpha; a novel neuroprotective mechanism

BACKGROUND AND PURPOSE

Although CB(1) receptor activation evokes neuroprotection in response to cannabinoids, some cannabinoids have been reported to be peroxisome proliferator activated receptor (PPAR) ligands, offering an alternative protective mechanism. We have, therefore, investigated the ability of a range of cannabinoids to activate PPAR alpha and for N-oleoylethanolamine (OEA), an endogenous cannabinoid-like compound (ECL), to evoke neuroprotection.

EXPERIMENTAL APPROACH

Assays of PPAR alpha occupancy and gene transactivation potential were conducted in cell-free and transfected HeLa cell preparations, respectively. In vivo estimates of PPAR alpha activation through fat mobilization and gene transcription were conducted in mice. Neuroprotection in vivo was investigated in wild-type and PPAR alpha gene-disrupted mice.

KEY RESULTS

The ECLs OEA, anandamide, noladin ether and virodhamine were found to bind to the purified PPAR alpha ligand binding domain and to increase PPAR alpha-driven transcriptional activity. The high affinity synthetic CB(1/2) cannabinoid agonist WIN 55212-2 bound to PPAR alpha equipotently with the PPARalpha agonist fenofibrate, and stimulated PPARalpha-mediated gene transcription. The phytocannabinoid delta 9 tetrahydrocannabinol was without effect. OEA and WIN 55212-2 induced lipolysis in vivo, while OEA pre-treatment reduced infarct volume from middle cerebral artery occlusion in wild-type, but not in PPAR alpha-null mice. OEA treatment also led to increased expression of the NFkappa B-inhibitory protein, Ikappa B, in mouse cerebral cortex, while expression of the NFkappa B-regulated protein COX-2 was inhibited.

CONCLUSIONS AND IMPLICATIONS

These data demonstrate the potential for a range of cannabinoid compounds, of diverse structures, to activate PPAR alpha and suggest that at least some of the neuroprotective properties of these agents could be mediated by nuclear receptor activation.

Cross-tolerance to otherwise lethal N-methyl-D-aspartate and oxygen-glucose deprivation in preconditioned cortical cultures

In vitro ischemic preconditioning induced by subjecting rat cortical cultures to nonlethal oxygen-glucose deprivation protects against a subsequent exposure to otherwise lethal oxygen-glucose deprivation. We provide evidence that attenuation of the postsynaptic N-methyl-D-aspartate (NMDA) receptor- and Ca(2+)-dependent neurotoxicity underlies oxygen-glucose deprivation tolerance. It is demonstrated that extended tolerance to otherwise lethal NMDA or oxygen-glucose deprivation can be induced by either of their sublethal forms of preconditioning. These four pathways are linked, since NMDA receptor blockade during preconditioning by oxygen-glucose deprivation eliminates tolerance. These results suggest that NMDA tolerance, induced by nonlethal activation of these receptors during oxygen-glucose deprivation preconditioning, underlies oxygen-glucose deprivation tolerance. Several neurotoxic downstream Ca(2+)-dependent signaling events specifically linked to NMDA receptor activation are attenuated during otherwise lethal oxygen-glucose deprivation in preconditioned cultures. Specifically, calpain activation, as well as degradation of microtubule-associated protein-2 and postsynaptic density-95, are attenuated 2 h following otherwise lethal NMDA treatment alone or oxygen-glucose deprivation in preconditioned cultures. Formation of microtubule-associated protein-2-labeled dendritic varicosities is also attenuated in preconditioned cultures within 1 h of lethal oxygen-glucose deprivation or NMDA application. Intracellular Ca(2+) levels, measured using the high- or low-affinity dyes Fluo-4 (K(d) approximately equal 345 nM) or Fluo-4FF (K(d) approximately equal 9.7 microM) respectively, are markedly attenuated during lethal oxygen-glucose deprivation in preconditioned cultures.Collectively, the results suggest the attenuation of the postsynaptic NMDA-mediated component of otherwise lethal oxygen-glucose deprivation through the suppression of Ca(2+)-dependent neurotoxic signaling, a mechanism that is initially induced by transient nonlethal activation of this receptor during ischemic preconditioning.

Prolonged molecular and clinical remission after treatment of a patient with follicular lymphoma with rituximab

Rituximab is a chimeric anti-CD20 monoclonal antibody that has approval for single agent therapy in the treatment of relapsed/refractory low grade or follicular non-Hodgkin's Lymphoma. In published phase II trials, molecular remissions of PCR detectable t(14;18) disease in the peripheral blood have been reported in up to 62% of patients by three months. We report a case of a patient who achieved prolonged clinical and molecular remission following a single four week course of Rituximab that has exceeded any previous remission achieved with chemo-radiotherapy. The implications of molecular remission as a surrogate of clinical remission and molecular relapse as a harbinger of clinical relapse are reviewed and discussed.

Transient NMDA receptor inactivation provides long-term protection to cultured cortical neurons from a variety of death signals

NMDA receptor antagonists, such as (+)-5-methyl-10, 11-dihydro-5H-dibenzo [a,d] cyclohepten-5,10-imine maleate (MK-801), potently block glutamate-induced neuronal death in myriad in vitro cell models and effectively attenuate ischemic damage in vivo. In this report, a novel role for MK-801 and other NMDA receptor antagonists in preconditioning neurons to withstand a wide range of subsequent lethal insults is described. A brief 30 min exposure to 0.1 microM MK-801, applied up to 96 hr before a "lethal" insult, protected primary cortical neurons from a diverse group of neurotoxic agents, including NMDA, beta-amyloid, staurosporine, etoposide, and oxygen-glucose deprivation. This neuroprotective preconditioning by MK-801 arose from transient NMDA receptor inactivation, because the noncompetitive NMDA receptor antagonists memantine and nylindin and the competitive antagonist AP-5 gave similar effects. MK-801 protection was dependent on new protein synthesis during the first 2 hr, but not from 2 to 5 hr, after MK-801 exposure. The MK-801 transient did not alter the ability of NMDA to trigger normally lethal [Ca(2+)](i) influx 48 hr later, but it did block early downstream signaling events coupled to NMDA neurotoxicity, including PKC inactivation and the activation of calpain. Moreover, MK-801 protected neurons from staurosporine-induced apoptosis, although caspase activation in these cells was unimpeded. It is likely that the stress associated with transient inactivation of NMDA receptors triggered a rapid compensatory survival response that provided long-term protection from a spectrum of insults, inducing apoptotic and nonapoptotic death. The possibility that MK-801 preconditioning blocks an event common to seemingly diverse death mechanisms suggests it will be an important tool for obtaining a clearer understanding of the salient molecular events at work in neuronal death and survival pathways.

Evaluation of glutathione-sensitive fluorescent dyes in cortical culture

The sensitivity of six fluorophores to glutathione (GSH) was evaluated in living rat cortical neuronal/glial mixed cultures during the first 23 days in vitro (DIV). Four of the dyes require glutathione-S-transferase (GST) to form a fluorescent conjugate, potentially conferring specificity for GSH: these included t-butoxycarbonyl-Leu-Met-7-amino-4-chloromethylcoumarin (CMAC), 7-amino-4-chloromethylcoumarin (CMAC-blue), monochlorobimane (MCB), and 5-chloromethylfluorescein diacetate (CMFDA). The final two dyes examined, 2,3-naphthalenedicarboxaldehyde (NDA) and o-phthaldehyde (OPD), do not require GST for adduct formation with GSH. To examine the specificity of the dyes for GSH, cultures grown less than 6 DIV were pretreated with diethyl maleate or DL-buthionine-(S, R)-sulfoximine to deplete endogenous GSH. This resulted in a substantial loss of staining by CMAC, CMAC-blue, and MCB and partial loss of staining by OPD, indicating specificity for GSH, while staining by CMFDA or NDA was not altered, indicating a lack of specificity for GSH. Neurons experienced a dramatic decline in GSH levels relative to astrocytes between 5-6 DIV, as shown by a loss of neuronal staining with CMAC, CMAC-blue and MCB. This decrease in staining was not due to a decrease in GST activity, as neurons stained with the GST-insensitive OPD also exhibited a decline in GSH-sensitive staining. Immunolabeling experiments demonstrated that CMAC staining co-localized with GFAP-positive astrocytes, but not with MAP-2-positive neurons, in 18 DIV cultures. Finally, CMAC was exploited as a specific morphological marker of astrocytes in cultures aged >5 DIV. CMAC staining was employed to monitor astrocyte proliferation and to resolve astrocytes in living mixed cultures co-loaded with the Ca(2+)-sensitive dye, calcium green 5N-AM. GLIA 30:329-341, 2000. Published 2000 Wiley-Liss, Inc.

Stem cell function and engraftment is not affected by "in vivo purging" with rituximab for autologous stem cell treatment for patients with low-grade non-Hodgkin's lymphoma

The chimeric anti-CD20 monoclonal antibody rituximab (Rituxan; IDEC Pharmaceuticals, San Diego, CA, and Genentech, Inc, San Francisco, CA) has recently been approved by the US Food and Drug Administration as single-agent treatment of relapsed/refractory low-grade or follicular non-Hodgkin's lymphoma. Initial results from the pivotal clinical trial revealed that response rates to rituximab were higher in patients who previously had high-dose therapy and autologous stem cell transplantation. We have initiated a clinical trial that combines the use of rituximab with high-dose chemotherapy followed by autologous stem cell transplantation for patients with chemosensitive relapsed follicular small cleaved or mantle cell lymphoma. A unique feature of this study is that in addition to eight maintenance infusions of rituximab after autologous stem cell transplantation, patients also received rituximab 375 mg/m2 2 days before a granulocyte colony-stimulating factor-mobilized stem cell collection as "in vivo purge." We report on preliminary results demonstrating the safety and efficacy of the in vivo purge on 10 patients undergoing stem cell mobilization, nine of whom have already undergone transplantation. The peripheral blood CD34+ counts were 14.92 and 20 x 10(6)/L on day 4 and day 5, respectively, of the stem cell mobilization with granulocyte colony-stimulating factor. This compares with 11.7 and 11.8 x 10(6)/L, respectively, for the control population. The median CD34 stem cell yield in the graft collection was 3.7 x 10(6)/kg in patients receiving rituximab in vivo purge compared with 3.1 x 10(6)/kg in the control population. The target stem cell collection was successfully collected in six of 10 patients in a 1-day single large-volume leukapheresis collection, while two patients required 2 days and the last two patients required 3 days. Functional assays revealed the stem cell colony-forming unit-granulocyte monocyte and burst-forming unit-erythrocyte to be 55 and 44 colonies per plate, respectively, for the patients receiving the in vivo rituximab purge. This compares favorably with 37 and 38.5 colonies per plate, respectively, for the control population. Neutrophil engraftment took a median of 11 days for both cohorts; platelet independence was achieved in 8 days compared with 10 days for the control population. The median number of platelet transfusions was two for patients receiving rituximab and 2.5 for the control group. Assessment of serum cytokines immediately before the rituximab infusion during the stem cell mobilization and immediately after revealed a twofold to sevenfold increase in interleukin-1beta, tumor necrosis factor-alpha, and interleukin-6. The polymerase chain reaction analysis for minimal residual disease in stem cell collections and in peripheral blood and bone marrow samples of these patients will help to determine the efficacy of rituximab in vivo purge on disease progression.

Evidence that brain-derived neurotrophic factor neuroprotection is linked to its ability to reverse the NMDA-induced inactivation of protein kinase C in cortical neurons

Several lines of evidence indicate that a rapid loss of neuronal protein kinase C (PKC) activity is a characteristic feature of cerebral ischemia and is a necessary step in the NMDA-induced death of cultured neurons. Exposing embryonic day 18 primary rat cortical neurons to 50 microM NMDA or 50 microM glutamate for 10 min caused approximately 80% cell death over the next 24 h, but excitotoxic death was largely averted, i.e., by 70-80%, in cells pretreated with brain-derived neurotrophic factor (BDNF). An 8-h preexposure to BDNF (50-100 ng/ml) maximally protected cortical cells from the effects of NMDA and glutamate, although the transient application of BDNF between 8 and 4 h before NMDA was equally protective. These effects of BDNF were abolished at supralethal, i.e., >100 microM, NMDA concentrations. It is significant that BDNF pretreatment prevented the inactivation of PKC in cortical cells normally seen 30 min to 2 h following lethal NMDA or glutamate exposure. This BDNF effect did not arise from changes in NMDA channel activity because neither whole-cell NMDA current amplitudes nor increases in intracellular free Ca2+ concentration were altered by the 8-h BDNF pretreatment. Furthermore, BDNF offered no neuroprotection to cells treated with the PKC inhibitors staurosporine (10-20 nM), calphostin C (1-2.5 microM), or GF-109203X (100 nM) at the time of NMDA addition. These results underscore the importance of PKC inactivation in glutamate-induced neuronal death. They also suggest that BDNF neuroprotection arises, at least in part, via its ability to block the mechanism by which pathophysiological Ca2+ influx through the NMDA receptor causes membrane PKC inactivation.

Neurobehavioral effects of chronic ingestion of Great Lakes chinook salmon

Cross-generational chronic feeding of either a 5 or a 20% lyophilized Lake Huron (LH) or Lake Ontario (LO) chinook salmon diet to rats caused no observable effects on many behavioral dimensions including activity, exploration, sensorimotor function, and stereotypy. As assessed by the Morris water maze and the radial arm maze, there was no diet-induced impairment of spatial learning or long-term memory. There was no evidence that the fish diets caused an exaggerated response to food reward reduction as had been observed previously for rats fed Oswego area Lake Ontario salmon. Effects of the fish diets with the exception of one statistically significant but probably meaningless effect on the Morris water maze for females were found only for male rats and only for males who ate the 20% diet. F1 male rats were reluctant to traverse a runway for a single pellet reward. Performance of the reference/working memory version of the radial arm maze was affected for the F1 LO-20 rats and for the F2 LH-20 rats. Until further research is conducted it would be unwise to ignore indications that male rats may show some effect of chronic consumption of the highest concentration of these diets, particularly on tasks that require intact frontocortical dopamine function.

Advanced therapeutics program

It has been a very exciting year for the advanced therapeutics team. We have seen our program become a reality, having successfully transplanted our first patients early this spring. The clinical and laboratory parts of our team work well together, never losing sight of our common goal-providing a state-of-the-art program for our patient population. The role of primary nurse coordinator remains a challenging one as the technological advancements in science and medicine continually provide us with the knowledge to make changes and improvements in our care.

Immunosuppressive toxicity of CAMPATH1H monoclonal antibody in the treatment of patients with recurrent low grade lymphoma

We have studied, as part of a group of international multicenter phase II clinical trials, the toxicity and effectiveness of CAMPATH1H administered intravenously three times a week in an outpatient setting to patients with recurrent or progressive low grade lymphoma. We report here on the toxicity and therapeutic results of the first seven patients treated before the study was closed prematurely because of unacceptable toxicity. Classical complete or partial responses of treatment were seen in three of seven patients. One complete response lasted 8.5 months and the other complete response is ongoing at 1 year. Responses occurred in nodal sites as well as in skin and peripheral blood. The first three or four antibody infusions in each patient was associated with grade 1 or 2 side-effects including rigor, fever, facial flushing, nausea, vomiting, hives, wheezes, hypotension, and/or diarrhea but these subsequently decreased or disappeared. The most significant toxicity was profound lymphopenia and associated infection, usually viral. Six of seven patients had culture or serologically documented infections and four patients had two or more such episodes. All infections responded to temporary discontinuation of antibody therapy and appropriate antiviral or antibiotic agents. We conclude that CAMPATH1H monoclonal antibody has therapeutic activity against low grade non-Hodgkin's lymphoma but that this activity is limited by marked lymphopenia and an unacceptably high frequency of serious infection at the dose and schedule used in this trial.

Combined treatment with MK-801 and nicardipine reduces global ischemic damage in the gerbil

BACKGROUND AND PURPOSE

Excessive activation of the N-methyl-D-aspartate receptor by glutamate produces an influx of Ca2+, which in turn is thought to lead to ischemic cell death. In this study we evaluated the combined treatment of the N-methyl-D-aspartate antagonist dizocilpine (MK-801) and the dihydropyridine Ca2+ channel blocker nicardipine for the reduction of hippocampal CA1 neuronal loss.

METHODS

Global ischemia was induced by bilateral carotid artery occlusion in the gerbil. Body temperature was maintained between 36.5 degrees C and 37.5 degrees C during surgery. MK-801 (5.0 mg/kg) was injected 15 minutes after occlusion whereas nicardipine was given by injection and via a micro-osmotic pump (1.0 mg/kg/day) for 3 days.

RESULTS

Postischemic treatment with MK-801 reduced CA1 cell loss by 27.0%, whereas nicardipine reduced CA1 cell loss by 13.3%. Combined postischemic treatment with these drugs yielded an additive, protective effect (44.5% reduction of CA1 loss) that did not appear to result from postischemic hypothermia as assessed by skull and rectal temperature recordings.

CONCLUSIONS

Our results demonstrate that MK-801 plus nicardipine significantly attenuates CA1 cell death after forebrain ischemia in the gerbil. Excitatory amino acid antagonists in combination with Ca2+ channel antagonists may be an effective therapy in patients exposed to global ischemic insult.

Parent education in preventing behaviour problems

The 'parent education package' (PEP) uses a combination of leaflets and health visitor intervention to help parents prevent the development of behaviour problems in their children. In evaluating PEP Kevin Hewitt et al found that, though popular with parents, the programme produced no actual behaviour change in their children. The results suggest that a successful prevention programme should perhaps focus on encouraging parents to think more positively about their children.

What do health visitors gain from behavioural workshops?

Health visitors' ratings of their role, competence, methods and effectiveness in resolving each of seven common types of preschool behaviour problem were obtained both prior to attending a behavioural training workshop and about 9 months later. At follow-up a structured interview examined their current practice in relation to preschool behaviour problems. Results suggest that these experienced health visitors perceived themselves as reasonably self-sufficient in dealing with these problems prior to training. Training had a significant but consolidating effect on these views. Possible mismatches between the health visitor's view of herself as a behaviour change agent and her training experiences in behavioural methods are examined and some suggestions are made regarding future liaison between health visitors and clinical child psychologists.

Sleep problems in pre-school children

Records were kept by one health visitor on the progress of nine children with sleeping difficulties. All the children were from socially disadvantaged families. The results reveal that the individual constructional treatment programmes which were applied by the health visitor were effective within a brief period and were not costly. Implications for health visiting practice are discussed and further issues about behavioural treatment and service delivery raised.

Catastrophic Landslide Deposits in the Karakoram Himalaya

In July 1986, three catastrophic landslides deposited about 20 x 10(6) cubic meters of debris on Bualtar Glacier in the Karakoram Himalaya. A sudden acceleration and superficial breakup of the glacier provided an opportunity to examine the fresh deposits in depth. Beneath a surface layer of large boulders, finer materials, mainly sand and silt, made up half of the total volume. The fine materials were formed during the rock avalanche from mostly intact, massive rock of the source zone. Velocity estimates suggest that this disaggregation occurred in less than 2 minutes. Coarse materials remained in bands of uniform lithology, but the fine materials had diffused throughout the landslides. A small amount of carbonate appears to have been calcined by frictional heating, presumably at the base of the initial sliding masses. These observations are relevant to understanding the mechanisms of catastrophic landslides. Other nearby rock avalanche deposits indicate that landslides are an important geomorphic process in the area and that they pose a continuing risk to human activity.

Resolving behaviour problems in preschool children: evaluation of a workshop for health visitors

Workshops on helping parents resolve behaviour problems in their preschool child were provided for all health visitors from one health district in Bristol, UK. An emphasis was placed upon engaging the parents as behaviour change agents, whilst providing a constructional approach to the treatment of this type of problem. The course was evaluated 3 months later. Results are discussed in terms of usefulness of course content as perceived by the health visitors, reported alterations to their health visiting practice and implications for future liaison between clinical psychologists and health visitors.

Postnatal classes on prevention of sleeplessness in young children

Parents of young babies attended evening classes on prevention of sleeping problems in pre-school children. The aim was to test the consumer-appeal of this preventative approach. Content focused on individual behavioural differences in babies as well as adaptation of parenting strategies to avoid some of the common pitfalls in the management of sleep-related behaviours. Parents' views were obtained and were favourable. Results are discussed in terms of the timing and format of similar prevention programmes.

Sequential chemotherapy and radiation for nasopharyngeal cancer: absence of long-term benefit despite a high rate of tumor response to chemotherapy

Between April 1981 and December 1983, patients with locoregional carcinoma of the nasopharynx were treated with two courses of chemotherapy administered before radiation therapy. Chemotherapy consisted of methotrexate, bleomycin, and cisplatin, which were administered at 3-week intervals, and radiation therapy was scheduled to commence 3 weeks after the start of the second course. Forty-nine of 51 consecutive patients were treated; only one patient progressed on chemotherapy, and of 36 patients with measurable neck nodes, eight had complete and 19 had partial clearance (greater than 50% decrease in cross-sectional area) of these nodes when assessed before initiation of radiotherapy. Despite the high rate of tumor response (75%; 95% confidence limits, 59% to 91%), the actuarial survival and disease-free survival curves were almost identical to those recorded for a consecutive group of 140 historical controls of similar stage distribution treated with radiation alone. This chemotherapy provided a high rate of tumor remission, but did not appear to convey long-term benefit to patients when used before radiation therapy.

Health visiting and pre-school children with behavioural problems in the County of South Glamorgan: an exploratory study

This study surveys firstly, using a modified semantic differential technique, how a sample of health visitors in the County of South Glamorgan perceived different behavioural problems in pre-school children. A selection of visiting records, covering a 1-year period, is also studied. Results from the semantic-differential indicate that health visitors perceive eating and sleeping as the most common problem areas. Hyperactivity and sleeping problems are seen as being the most difficult to deal with and the most disruptive to family life. Although health visitors generally feel it is necessary to follow up children with behaviour problems, they find these difficult to resolve. About one third of children are referred to other agencies. Visiting records reveal that children with hyperactivity and sleeping problems receive the highest number of visits from health visitors and that there is little improvement in these children over a period of 1 year. An extension of the health visitor's role and training to include behavioural treatments for pre-school children is discussed.

Diagnosed mental disorder in children and use of health services in four organized health care settings

The authors present comparative data on the extent, nature, and impact of diagnosed mental disorder among children under 18 years of age seen during 1975 in four organized health care settings. Between 3.3% and 10.1% of the children seen were diagnosed as having a mental disorder in the study year, representing an annual prevalence of between 2.2% and 8.2% of the "covered" child populations. Transient situational disturbances, behavior disorders, and special symptoms were the most common diagnoses; the more severe disorders (organic brain disease, schizophrenia, and affective and other psychoses) accounted for less than 4% of all diagnosed mental disorder. Patients with diagnosed mental disorder used non-mental-health services (except those of pediatricians) appreciably more often than did patients without such a diagnosis.