Cyclooxygenase inhibitors modulate the p53/HDM2 pathway and enhance chemotherapy-induced apoptosis in neuroblastoma

Cyclooxygenase-2 (COX-2) is upregulated in many tumors including neuroblastoma, and its overexpression has been implicated in resistance to p53-dependent apoptosis. Although p53 is rarely mutated in neuroblastoma, the p53 protein is rendered inactive via several mechanisms including sequestration in the cytoplasm. Here, we show that COX inhibitors inhibit the growth of neuroblastoma and when combined with low doses of chemotherapy, exert synergistic effects on neuroblastoma cells. Following COX inhibitor treatment, HDM2, which targets p53 for ubiquitin-mediated degradation, is downregulated, resulting in an attenuation of p53 ubiquitination and an increase in p53 half-life. The level of HDM2 phosphorylation at ser166, which influences both HDM2 and p53 subcellular distribution, is markedly diminished in response to COX inhibitors and is associated with increased p53 nuclear localization. Combining COX inhibitors with low-dose chemotherapy potentiates apoptosis and p53 stability, nuclear localization, and activity. p53 knockdown by siRNA resulted in the rescue of COX-inhibitor-treated cells, indicating that COX inhibitor-induced apoptosis is, at least in part, p53-dependent. Taken together, these results provide the first evidence that COX inhibitors enhance chemosensitivity in neuroblastoma via downregulating HDM2 and augmenting p53 stability and nuclear accumulation.

Tumour necrosis factor (TNFalpha) as a novel therapeutic target in symptomatic corticosteroid dependent asthma

BACKGROUND

Tumour necrosis factor alpha (TNFalpha) is a major therapeutic target in a range of chronic inflammatory disorders characterised by a Th1 type immune response in which TNFalpha is generated in excess. By contrast, asthma is regarded as a Th2 type disorder, especially when associated with atopy. However, as asthma becomes more severe and chronic, it adopts additional characteristics including corticosteroid refractoriness and involvement of neutrophils suggestive of an altered inflammatory profile towards a Th1 type response, incriminating cytokines such as TNFalpha.

METHODS

TNFalpha levels in bronchoalveolar lavage (BAL) fluid of 26 healthy controls, 42 subjects with mild asthma and 20 with severe asthma were measured by immunoassay, and TNFalpha gene expression was determined in endobronchial biopsy specimens from 14 patients with mild asthma and 14 with severe asthma. The cellular localisation of TNFalpha was assessed by immunohistochemistry. An open label uncontrolled clinical study was then undertaken in 17 subjects with severe asthma to evaluate the effect of 12 weeks of treatment with the soluble TNFalpha receptor-IgG1Fc fusion protein, etanercept.

RESULTS

TNFalpha levels in BAL fluid, TNFalpha gene expression and TNFalpha immunoreative cells were increased in subjects with severe corticosteroid dependent asthma. Etanercept treatment was associated with improvement in asthma symptoms, lung function, and bronchial hyperresponsiveness.

CONCLUSIONS

These findings may be of clinical significance in identifying TNFalpha as a new therapeutic target in subjects with severe asthma. The effects of anti-TNF treatment now require confirmation in placebo controlled studies.

[Analysis of paediatric neuro-oncological information on the Internet in German language]

BACKGROUND

The fast growing internet offers easy access to medical information. So far there are limited data concerning the quality of this information. This study examined quality and readability of paediatric neuro-oncological information on the internet in german language.

METHOD

Using the search terms "medulloblastoma", "ependymoma", "craniopharyngeoma", "brainstem glioma" and "low grade astrocytoma" in six different search engines, the first 30 universal/uniform resource locators (URLs) of each search engine were assessed. Appropriate Web sites were evaluated in regards to quality using DISCERN-Instrument and checklist rating system. Readability was rated by Flesch Reading Ease score.

RESULTS

Out of 889,56 web sites remained evaluable. Most of the sites rated as poor to very poor (49 %), 30 % rated as fair and 21 % as good to very good. Readability was scored as very difficult with complex vocabulary content limiting the usefulness of good web sites.

CONCLUSIONS

Search-ing for childhood brain tumours via internet is time consuming and most often ineffective. There is a lack of high-quality and comprehensible information on childhood brain tumours on german web sites. Cooperation of scientific medical societies and the Federal Ministry of Health is essential to provide comprehensible and high-quality information on internet as an effective and supportive resource for patients and their relatives.

Nebulised salbutamol administered during sputum induction improves bronchoprotection in patients with asthma

BACKGROUND

Inhalation of hypertonic or even isotonic saline during sputum induction may cause bronchospasm in susceptible patients with asthma, despite premedication with 400 microg inhaled salbutamol delivered by pressurised metered dose inhaler (pMDI). The bronchoprotection afforded by additional inhaled salbutamol administered through the ultrasonic nebuliser during sputum induction was investigated.

METHODS

Twenty patients with moderate to severe asthma underwent sputum induction by inhaling saline 4.5% (or 0.9% if post-bronchodilation forced expiratory volume in 1 second (FEV1) <65% predicted) for 10 minutes according to two protocols given 1 week apart in random order. At visit A the patients received 400 microg salbutamol administered through a pMDI+spacer 20 minutes before induction while at visit B the premedication was supplemented by 1500 microg nebulised salbutamol inhaled throughout the induction procedure. Both the investigator and the patients were blind to the nebulised solution used. FEV1 was recorded during sputum induction at 1, 3, 5, and 10 minutes. Sputum cell counts and histamine, tryptase and albumin levels in the supernatants were determined.

RESULTS

The mean (SE) maximal reduction in FEV1 over the 10 minute period of sputum induction was 11.7 (2.8)% at visit A, which was significantly greater than at visit B (2.6 (1.2)%; mean difference 9% (95% CI 2.7 to 15.4), p<0.01). Total and differential sputum cell counts as well as albumin, tryptase, and histamine levels did not differ between the two visits.

CONCLUSION

The addition of inhaled salbutamol through an ultrasonic nebuliser markedly improves bronchoprotection against saline induced bronchoconstriction in patients with moderate to severe asthma undergoing sputum induction without affecting cell counts and inflammatory markers.

Bone marrow transplantation for paediatric AML in first remission: a systematic review and meta-analysis

For children with AML in CR1, the major consolidation therapies are BMT, ABMT and intensive chemotherapy. The relative effectiveness of these strategies is still debated. We conducted a systematic review and meta-analysis of trials to determine the effectiveness of BMT and ABMT in CR1 in paediatric AML. Eligible studies enrolled patients <21 years from 1985 to 2000 with AML in CR1. Two groups of studies were identified: (1) Those comparing the outcome of patients with and without a histocompatible family donor; and (2) Randomised controlled trials (RCT) comparing ABMT with non-myeloablative chemotherapy. The relative risk statistic was calculated for outcomes of interest in each trial. If there was no excessive heterogeneity between trials the results were pooled, and an overall relative risk and risk difference for treatment effect across trials were calculated. Results of the analysis showed that allocation to BMT reduced risk of relapse and improved disease-free and overall survival. For ABMT, heterogeneity of effect between RCTs prevented pooling of results. In conclusion, BMT from a histocompatible family donor improves patient outcome. Data are insufficient to determine whether this is true for all subgroups of AML, and whether ABMT is superior to non-myeloablative chemotherapy. An individual patient data meta-analysis is required to further evaluate the available data.

Preparation of patients for anaesthesia - achieving quality care

Implementation of anaesthesia begins with a preoperative assessment of the surgical patient and development of an anaesthetic plan. Preparation of the patient includes the preoperative assessment, review of preoperative tests, optimisation of medical conditions, adequate preoperative fasting, appropriate premedication, and the explanation of anaesthetic risk to patients. The goals of preoperative preparation are to reduce the morbidity of surgery, to increase the quality while decreasing the cost of perioperative care, and to return the patient to desirable functioning as quickly as possible. A knowledgeable anaesthesiologist is the 'final clinical gatekeeper', who coordinates perioperative management and ensures that the patient is in the optimal state for anaesthesia and surgery.

Induced sputum: comparison between isotonic and hypertonic saline solution inhalation in patients with asthma

BACKGROUND

Sputum induction by hypertonic saline solution inhalation is widely used to study airways secretions in patients with asthma. However, hypertonic saline solution is a potent indirect bronchoconstrictor.

STUDY OBJECTIVES

We studied the validity of isotonic saline solution (0.9%) inhalation as a means to induce sputum by comparing it to hypertonic saline solution (4.5%) inhalation.

PATIENTS

Sixteen patients with moderate-to-severe asthma reporting a clinical history of mucus hypersecretion.

METHODS

Subjects underwent sputum induction twice at 1-week intervals. Saline solution (hypertonic or isotonic) was inhaled for three periods of 5 min. The parameters assessed in sputum samples were cell counts, sodium, eosinophil cationic protein (ECP), and albumin concentrations, osmolality, and pro-matrix metalloproteinase (MMP)-9 activity by zymography.

RESULTS

The maximal fall in peak expiratory flow during sputum induction was greater after inhalation of hypertonic saline solution than after inhalation of isotonic saline solution (p < 0.01). Each subject produced analyzable sputum on both visits. There were no statistically significant differences in total and differential sputum cell counts, and the reproducibility coefficients were high for eosinophils and neutrophils when comparing the two methods. Likewise, sputum levels of ECP and albumin as well as sputum pro-MMP-9 activity were not different between the two methods, and were highly reproducible as shown by high intraclass coefficients (Ri) of correlation (0.72, 0.74, and 0.77 for ECP, albumin, and pro-MMP-9, respectively). Sputum sodium concentrations and osmolality were higher after inhalation of hypertonic saline solution (p < 0.05).

CONCLUSION

In patients with moderate-to-severe asthma reporting a clinical history of mucus hypersecretion, inducing sputum by isotonic or hypertonic saline solution inhalation leads to comparable results in eosinophil and neutrophil cell counts and fluid phase mediators/proteins.

The relationship between atopic status and IL-10 nasal lavage levels in the acute and persistent inflammatory response to upper respiratory tract infection

We examined the influence of atopy on virus-induced airway inflammation by comparing the nasal response to naturally acquired upper respiratory tract infection in atopic and nonatopic subjects by measurement of cytokine, chemokine, and mediator levels in nasal lavage from 44 adults (23 atopic) taken during the acute and the convalescent phases of the common cold. Nasal aspirates were examined for the presence of upper respiratory viruses by RT-PCR. In atopic and nonatopic subjects there were increased levels of IL-1beta, IL-6, IL-8, TNF-alpha, RANTES, sICAM-1, MPO, ECP, IL-10, and IFN-gamma in nasal lavage during the acute compared with the convalescent phase (p < 0.001). During the acute phase histamine levels were significantly higher in the atopic than in the nonatopic subjects (p < 0.05), whereas IL-10 levels were significantly greater in the nonatopic than in the atopic subjects (p < 0.05). At convalescence levels of IL-1beta, IL-6, sICAM-1, ECP, RANTES and albumin were significantly higher in the atopic group (p < 0.05). An upper respiratory tract virus was found in 27 volunteers (61%) during the acute stage and in two volunteers (4%) at convalescence. We conclude that virus-induced inflammatory changes within the nose are more prolonged in atopic than in nonatopic subjects and that this is associated with reduced IL-10 levels in atopic compared with nonatopic subjects during the acute phase of upper respiratory tract infection.

Should adolescents be vaccinated against hepatitis A: the Hong Kong experience

Hong Kong is a well developed city in the center of an endemic region for hepatitis A. The age at which hepatitis A occurs has shifted from childhood and adolescence to adults like many western countries. There is a high chance of outbreaks with the introduction of infection from neighbouring countries. Reducing the susceptibility of a population by vaccination can eliminate the diseases but updated sero-epidemiological data is needed to analyse the level of natural immunity, and identify those susceptible to infection for preventive measures. This study conducted amongst secondary school children seeks to identify those who are at risk and to obtain data on the present sero-prevalence of anti-HAV. Overall prevalence of anti-HAV in this age group was 7% increasing with age. Analysed by multiple regression model, those students living in mainland China over 3 years had odds ratio of 31.6 (95% c. i. 17.4-57.3) compared with those born in Hong Kong. Students with a father in a skilled occupation and an education level of secondary school or above, and both parents with secondary education or above, had an odds ratio of 0.22 (95% c.i. 0.07-0.7) and 0.35 (95% c.i. 0. 17-0.72) associated with presence of anti-HAV, respectively. Improved socio-economic state exposes higher proportion of the population at risk. Immunisation is worthwhile to be considered for the adolescents in Hong Kong. Prevaccination screening is cost effective only for those adolescents who are most likely to have natural immunity.

Changing hepatitis A epidemiology among Hong Kong Chinese adolescents: what are the implications?

OBJECTIVE

To study the sero-epidemiology of hepatitis A virus (HAV) among adolescents in Hong Kong and analyse the changing patterns of the infection rates.

DESIGN

Cross sectional study.

SETTING

Secondary school students.

SUBJECTS

One thousand, five hundred and eighty students were randomly selected from 12 schools in four regions of Hong Kong.

MAIN OUTCOME MEASURES

Anti-HAV status.

RESULTS

The overall prevalence of anti-HAV is 7%. The sero-prevalence for age group 11-20 y has fallen compared with 44.8% in 1978, 17.1% in 1987 and 11.2% in 1989. Those adolescents born in mainland China, who are frequent travellers and had a longer period of residence in mainland China were shown to have a higher prevalence of anti-HAV.

CONCLUSION

The changing epidemiology of HAV indicates that Hong Kong will have a large proportion of susceptible young adults. Because of its geographic situation and import of most its food supplies from less developed countries, for epidemiological purposes the inhabitants can be compared to western travellers staying in a five star hotel in a less developed country. The risk of an outbreak of HAV is to be expected. Vaccination has the potential to serve as an effective prevention for adolescents living in countries whose circumstances are similar to Hong Kong.

Bronchial eosinophilic infiltration in Crohn's disease in the absence of pulmonary disease

BACKGROUND

Immunological and functional bronchopulmonary abnormalities may be present in up to two-thirds of patients with Crohn's disease. Having recently described a mild increase in methacholine airways responsiveness in these patients, we investigated whether this physiological abnormality is associated with bronchial inflammation since it has previously been described in asthma.

METHODS

Eighteen patients with Crohn's disease and 15 healthy controls matched for age, atopy and smoking habit, were studied. All the subjects underwent a bronchial methacholine challenge (1, 4 and 16 mg/mL) and a sputum induction by inhalation of hypertonic saline (NaCl 4.5%). The sputum samples were analysed for their cellular composition as well as for the levels of several mediators and proteins in the fluid phase, including eosinophil cationic protein (ECP), myeloperoxydase, albumin, alpha2-macroglobulin, interleukin-8 (IL-8), IgA and IL-8/immunoglobulin A complexes.

RESULTS

When compared to control subjects, patients with Crohn's disease had significantly higher sputum eosinophil counts (14.5% [0-79.9%] vs 0.2% [0-2.3%]; P < 0. 001) and ECP levels (26.2 microg/L [4-124.2 microg/L] vs 9.8 microg/L [0-94.2 microg/L]; P < 0.05). However, patients with Crohn's disease had no sign of increased plasma exudation as reflected by sputum levels of albumin and alpha2-macroglobulin similar to those seen in control subjects. Furthermore the sputum levels of IL-8, IgA and IL-8/IgA complexes were not significantly different between the two groups. The magnitude of the fall in forced expiratory volume in 1 s after methacholine inhalation was significantly increased in Crohn's disease patients although it did not correlate with the extent of sputum eosinophilia or with the sputum ECP levels.

CONCLUSIONS

Crohn's disease patients without any clinical respiratory involvement have airway eosinophilia without local increased plasma exudation. However, bronchial eosinophilia in Crohn's disease per se is not sufficient to induce clinically significant airway hyperresponsiveness, suggesting that other factors than bronchial eosinophilic infiltration are required for the clinical expression of an airway instability.

A survey of elderly diabetic patients attending a community clinic in Hong Kong

A cross-sectional survey was conducted on Chinese diabetic patients attending a community clinic in Hong Kong. A questionnaire, physical examination and blood tests were administered. Of 155 adults with diabetes mellitus recruited, the mean age was 63 years (SD 10.3), 77.4% were female and 41.9% illiterate. Half the patients achieved adequate knowledge scores. Knowledge was found to be associated with education level (OR 4.3, 95% CI 1.8, 10.0), longer disease duration (OR 3.2, 95% CI 1.4, 7.4) and complications (OR 0.3, 95% CI 0.1, 0.8). No correlation was found between knowledge and attitude or practice. Attitude was found to be associated with practice (OR 1.2, 95% CI 1.0, 1.3) and male gender (OR 2.9, 95% CI 1.1, 7.5); practice was associated with hypertension (0.5, 95% CI 0.2, 0.9). Older less educated Chinese diabetic patients can be educated about diabetes management, but knowledge does not always translate into practice.

Inflammatory mediators in naturally occurring rhinitis

BACKGROUND

The mediators released during the allergic inflammatory reaction induce the clinical symptoms of the allergic disease and although there have been numerous studies investigating mediator release in allergen challenge models of allergic rhinitis very few have extended this approach to the study of natural disease.

OBJECTIVE

The aim of this investigation was therefore to measure mast cell and eosinophil mediator levels and indices of vascular permeability in naturally occurring rhinitis.

METHODS

Three groups of subjects were studied, normal non-rhinitics, seasonal allergic rhinitics in and out of the grass pollen season and perennial allergic rhinitics. Mediators were recovered using the technique of nasal lavage and the levels of tryptase, histamine, eosinophil cationic protein and albumin were determined. In addition, eosinophils were enumerated in nasal smears as an indices of underlying inflammation.

RESULTS

The levels of tryptase, eosinophil cationic protein and albumin were significantly higher in the lavage recovered from the symptomatic seasonal allergic rhinitics than when asymptomatic (P = 0.05, P = 0.003, P = 0.009, respectively). These levels of eosinophil cationic protein and albumin were also significantly higher than those of the normal non-rhinitics (P = 0.0008, P = 0.0.003, respectively). In the perennial allergic rhinitics the levels of tryptase, eosinophil cationic protein and albumin were higher than the normal non-rhinitics (P < 0.0001, P = 0.0003, P = 0.0001, respectively). The levels of tryptase and histamine were higher in the perennial allergic rhinitics than the seasonal allergic rhinitics (P = 0.0003, P = 0.006, respectively). These changes in mediator levels were accompanied by a significant influx of eosinophils into the nasal mucosa of both the symptomatic seasonal rhinitics, compared with asymptomatic (P = 0.04) and normal controls (P = 0.0006) and the perennial rhinitics compared to normal controls (P = 0.03).

CONCLUSION

These results indicate that in both naturally occurring seasonal allergic rhinitis and perennial allergic rhinitis mast cell and eosinophil activation occurs and this is accompanied by an increase in vascular permeability. These measurements in lavage fluid provide a method of monitoring the mucosal cellular events in response to therapy.

Micro- and macrogeographical genetic structure of colonies of naked mole-rats Heterocephalus glaber

Patterns of genetic structure in eusocial naked mole-rat populations were quantified within and among geographically distant populations using multilocus DNA fingerprinting and mitochondrial DNA (mtDNA) sequence analysis. Individuals within colonies were genetically almost monomorphic, sharing the same mtDNA control region haplotype and having coefficients of band sharing estimated from DNA fingerprints ranging from 0.93 to 0.99. Family analysis of a hybrid captive colony of naked mole-rats with increased levels of genetic variability using multilocus DNA fingerprinting gave results consistent with Mendelian inheritance, and has revealed for the first time that multiple paternity can occur. In a survey of wild colonies from Ethiopia, Somalia and locations in northern and southern Kenya, we have examined mtDNA control region sequence variation in 42 individuals from 15 colonies, and together with multilocus DNA fingerprinting and mtDNA cytochrome-b sequence analysis in selected individuals have shown that these populations show considerable genetic divergence. Most of the variance in sequence divergence was found to be between geographical locations (phi ct = 0.68) and there was a significant correlation between sequence divergence and geographical separation of haplotypes. Six colonies from Mtito Andei in southern Kenya shared the same control region haplotype, suggesting a recent common maternal ancestor. In contrast, out of four colonies at Lerata in north Kenya, three haplotypes were identified, and phylogenetic analysis suggests that this area may be a zone where two distinct lineages are in close proximity. Genetic distances were maximal between Ethiopian and southern Kenyan populations at 5.8% for cytochrome-b, and are approaching interspecific values seen between other Bathyergids.

Histamine and the nasal vasculature: the influence of H1 and H2-histamine receptor antagonism

The aim was to determine the effect of H1- and H2-receptor blockade on histamine-induced changes in nasal airways resistance and lavage protein concentrations. Normal subjects were pretreated with oral cetirizine or ranitidine in a double-blind and randomized manner. Measurements of the concentration of total protein and albumin in nasal lavage fluid together with nasal airway resistance were made before and after challenge. Any effect of treatment was assessed by comparing the areas under the time-response curves. In all nine subjects available for analysis histamine caused an immediate increase in all measurements. Ranitidine reduced the maximum increase in nasal airway resistance, but this effect was significant only in combination with certirizine. The increase in lavage total protein and albumin concentrations was almost completely abolished by cetirizine, whereas ranitidine had less effect. We conclude that the histamine H1-receptor has the greatest effect on changes in nasal vascular permeability induced by topical histamine, whereas the H2-receptor has the greatest effect on nasal obstruction.

Impairment in shifting attention in autistic and cerebellar patients

MRI and autopsy evidence of early maldevelopment of cerebellar vermis and hemispheres in autism raise the question of how cerebellar maldevelopment contributes to the cognitive and social deficits characteristic of autism. Compared with normal controls, autistic patients and patients with acquired cerebellar lesions were similarly impaired in a task requiring rapid and accurate shifts of attention between auditory and visual stimuli. Neurophysiologic and behavioral evidence rules out motor dysfunction as the cause of this deficit. These findings are consistent with the proposal that in autism cerebellar maldevelopment may contribute to an inability to execute rapid attention shifts, which in turn undermines social and cognitive development, and also with the proposal that the human cerebellum is involved in the coordination of rapid attention shifts in a fashion analogous to its role in the coordination of movement.

Impairment in shifting attention in autistic and cerebellar patients

MRI and autopsy evidence of early maldevelopment of cerebellar vermis and hemispheres in autism raise the question of how cerebellar maldevelopment contributes to the cognitive and social deficits characteristic of autism. Compared with normal controls, autistic patients and patients with acquired cerebellar lesions were similarly impaired in a task requiring rapid and accurate shifts of attention between auditory and visual stimuli. Neurophysiologic and behavioral evidence rules out motor dysfunction as the cause of this deficit. These findings are consistent with the proposal that in autism cerebellar maldevelopment may contribute to an inability to execute rapid attention shifts, which in turn undermines social and cognitive development, and also with the proposal that the human cerebellum is involved in the coordination of rapid attention shifts in a fashion analogous to its role in the coordination of movement.