Common west African HLA antigens are associated with protection from severe malaria

A large case-control study of malaria in West African children shows that a human leucocyte class I antigen (HLA-Bw53) and an HLA class II haplotype (DRB1*1302-DQB1*0501), common in West Africans but rare in other racial groups, are independently associated with protection from severe malaria. In this population they account for as great a reduction in disease incidence as the sickle-cell haemoglobin variant. These data support the hypothesis that the extraordinary polymorphism of major histocompatibility complex genes has evolved primarily through natural selection by infectious pathogens.

Human cerebral malaria: association with erythrocyte rosetting and lack of anti-rosetting antibodies

Plasmodium falciparum isolates from 24 Gambian children with cerebral malaria and 57 children with mild forms of the disease were assessed for their ability to form erythrocyte rosettes. All isolates from the children with cerebral malaria were able to form rosettes, whereas those from children with mild forms of the disease did not form rosettes, or had a significantly lower rosetting rate. Plasma of children with cerebral malaria lacked anti-rosetting activity, whereas plasma of children with mild disease could often disrupt rosettes in vitro. A monoclonal antibody to P falciparum histidine rich protein (PfHRP1/KP/KAHRP) disrupted rosettes of many of the isolates in vitro indicating that the rosetting ligand is relatively conserved compared with ligands associated with endothelial cytoadherence. The findings strongly support the hypothesis that erythrocyte rosetting contributes to the pathogenesis of cerebral malaria and suggest that anti-rosetting antibodies protect against cerebral disease.

Cancer prevalence in the United Kingdom: estimates for 2008

BACKGROUND

Identifying and addressing the requirements of cancer survivors is currently a high priority for the NHS, yet little is known about the population of cancer survivors in the United Kingdom.

METHODS

Data from cancer registries in England, Northern Ireland, Scotland and Wales were analysed to provide limited-duration prevalence estimates for 2004. Log-linear regression models were used to extend these to complete prevalence estimates. Trends in prevalence from 2000 to 2004 were used to project complete prevalence estimates forward from 2004 to 2008.

RESULTS

We estimated that in total, there were 2 million cancer survivors in the United Kingdom at the end of 2008, approximately 3% of the population overall and 1 in 8 of those aged 65 years and more. Prostate and female breast cancers were the most prevalent. The number of cancer survivors is increasing by approximately 3% each year. Estimates are also provided by time since diagnosis.

CONCLUSION

These estimates are the most up-to-date available, and as such will be useful for statutory and voluntary sector organisations that are responsible for planning and providing treatment and support to cancer survivors in the United Kingdom.

Lactic acidosis and hypoglycaemia in children with severe malaria: pathophysiological and prognostic significance

Serial clinical and metabolic changes were monitored in 115 Gambian children (1.5-12 years old) with severe malaria. Fifty-three children (46%) had cerebral malaria (coma score < or = 2) and 21 (18%) died. Admission geometric mean venous blood lactate concentrations were almost twice as high in fatal cases as in survivors (7.1 mmol/L vs. 3.6 mmol/L; P < 0.001) and were correlated with levels of tumour necrosis factor (r = 0.42, n = 79; P < 0.0001) and interleukin 1-alpha (r = 0.6, n = 34; P < 0.0001). Admission blood venous glucose concentrations were lower in fatal cases than survivors (3.2 mmol/L, vs. 5.8 mmol/L; P < 0.0001). Treatment with quinine was associated with significantly more episodes of post-admission hypoglycaemia when compared with artemether or chloroquine. After treatment, lactate concentrations fell rapidly in survivors but fell only slightly, or rose, in fatal cases. Plasma cytokine levels fluctuated widely after admission. Sustained hyperlactataemia (raised lactate concentrations, 4 h after admission) proved to be the best overall prognostic indicator of outcome in this series. Lactic acidosis is an important cause of death in severe malaria.

The aerosol box for intubation in coronavirus disease 2019 patients: an in-situ simulation crossover study

The coronavirus disease 2019 pandemic has led to the manufacturing of novel devices to protect clinicians from the risk of transmission, including the aerosol box for use during tracheal intubation. We evaluated the impact of two aerosol boxes (an early‐generation box and a latest‐generation box) on intubations in patients with severe coronavirus disease 2019 with an in‐situ simulation crossover study. The simulated process complied with the Safe Airway Society coronavirus disease 2019 airway management guidelines. The primary outcome was intubation time; secondary outcomes included first‐pass success and breaches to personal protective equipment. All intubations were performed by specialist (consultant) anaesthetists and video recorded. Twelve anaesthetists performed 36 intubations. Intubation time with no aerosol box was significantly shorter than with the early‐generation box (median (IQR [range]) 42.9 (32.9–46.9 [30.9–57.6])s vs. 82.1 (45.1–98.3 [30.8–180.0])s p = 0.002) and the latest‐generation box (52.4 (43.1–70.3 [35.7–169.2])s, p = 0.008). No intubations without a box took more than 1 min, whereas 14 (58%) intubations with a box took over 1 min and 4 (17%) took over 2 min (including one failure). Without an aerosol box, all anaesthetists obtained first‐pass success. With the early‐generation and latest‐generation boxes, 9 (75%) and 10 (83%) participants obtained first‐pass success, respectively. One breach of personal protective equipment occurred using the early‐generation box and seven breaches occurred using the latest‐generation box. Aerosol boxes may increase intubation times and therefore expose patients to the risk of hypoxia. They may cause damage to conventional personal protective equipment and therefore place clinicians at risk of infection. Further research is required before these devices can be considered safe for clinical use.

Accuracy of reporting of family history of colorectal cancer

BACKGROUND AND AIMS

Family history is used extensively to estimate the risk of colorectal cancer but there is considerable potential for recall bias and inaccuracy. Hence we systematically assessed the accuracy of family history reported at interview compared with actual cancer experience in relatives.

METHODS

Using face to face interviews, we recorded family history from 199 colorectal cancer cases and 133 community controls, totalling 5637 first and second degree relatives (FDRs/SDRs). We linked computerised cancer registry data to interview information to determine the accuracy of family history reporting.

RESULTS

Cases substantially underreported colorectal cancer arising both in FDRs (sensitivity 0.566 (95% confidence interval (CI) 0.433, 0.690); specificity 0.990 (95% CI 0.983, 0.994)) and SDRs (sensitivity 0.271 (95% CI 0.166, 0.410); specificity 0.996 (95% CI 0.992, 0.998)). There was no observable difference in accuracy of reporting family history between case and control interviewees. Control subjects similarly underreported colorectal cancer in FDRs (sensitivity 0.529 (95% CI 0.310, 0.738); specificity 0.995 (95% CI 0.989, 0.998)) and SDRs (sensitivity 0.333 (95% CI 0.192, 0.512); specificity 0.995 (95% CI 0.991, 0.995)). To determine practical implications of inaccurate family history, we applied family history criteria before and after record linkage. Only two of five families reported at interview to meet surveillance criteria did so after validation, whereas only two of six families that actually merited surveillance were identified by interview.

CONCLUSIONS

This study has quantified the inaccuracy of interview in identifying people at risk of colorectal cancer due to a family history. Colorectal cancer was substantially underreported and so family history information should be interpreted with caution. These findings have considerable relevance to identifying patients who merit surveillance colonoscopy and to epidemiological studies.

Initial effects of the grounding of the tanker Braer on health in Shetland. The Shetland Health Study Group

OBJECTIVE

To determine if the oil spillage from the tanker Braer had any immediate health effects on the exposed resident population.

DESIGN

Cohort study with a comparison against controls, exposure status being assigned on the basis of geographical location.

SETTING

Rural Shetland.

SUBJECTS

All those resident on or after 5 January 1993 (day 0) within 4.5 km of the site of tanker's grounding. Controls matched for sex and age were drawn from a general practice list 95 km distant.

OUTCOME MEASURES

Demographic details; smoking and alcohol consumption; perception of health and reported presence or absence of specific symptoms; peak expiratory flow; results of haematology, liver and renal function tests, and blood and urine toxicology.

RESULTS

Of subjects contacted, 420 (66%) exposed people and 92 (68%) controls were studied; 56 non-attenders were surveyed. Principal health effects arose on days 1 and 2 and were headache, throat irritation, and itchy eyes. No significant differences between those exposed and controls were found for any of the biological markers. Toxicological studies did not show any exposures that are known to affect human health.

CONCLUSIONS

The study confirmed the anecdotal reports of certain acute symptoms. No evidence of pulmonary, haematological, renal, or hepatic damage was detected at the population level. Toxicological samples from exposed people did not find levels known to affect human health. Further studies are required to ascertain whether there have been any long term effects on the population.

The systemic bioavailability of buprenorphine by various routes of administration

The systemic bioavailability of buprenorphine has been studied in female rats following single doses (200 microgram kg-1) administered by one of six different routes. Relative to the 100% bioavailability from the intraarterial route the mean bioavailabilities were intravenous, 98%; intrarectal, 54%; intrahepatoportal, 49%; sublingual, 13%; and intraduodenal, 9.7%. Area under the curve analysis of buprenorphine concentrations in blood showed the relative fractions of drug extracted (first pass) by gut, liver and lung to be 0.80, 0.50 and 0.02 respectively, In situ absorption studies showed that the poor availability of intraduodenally administered buprenorphine is not due to slow or incomplete absorption.

Biliary excretion, metabolism and enterohepatic circulation of buprenorphine

1. After intramuscular administration of [3H]buprenorphine to rats, dogs, rhesus monkeys and one human volunteer, most of the dosed radioactivity was excreted in the faeces, indicating biliary excretion and a possible enterohepatic circulation of the drug in these species. 2. After intravenous administration of [3H]buprenorphine (100 microgram/kg) to bile-duct cannulated rats, over 90% of the administered radioactivity was excreted in bile within 48 h after dosing. 3. The major drug-related component in rat bile was buprenorphine glucuronide. N-Dealkylated buprenorphine (again conjugated) was also present and a sex difference in the extent of N-dealkylation was apparent. 4. Intraduodenal infusion of rats with bile from rats dosed with [3H]buprenorphine produced a slow, although extensive, excretion of drug-related material in the bile of the recipient animals.

How accurate are Scottish cancer registration data?

In order to assess the accuracy of Scottish cancer registration data, a random sample of 2,200 registrations, attributed to the year 1990, was generated. Relevant medical records were available for review in 2,021 (92%) cases. Registration details were reabstracted from available records and compared with data in the registry. Discrepancies in identifying items of data (surname, forename, sex and date of birth) were found in 3.5% of cases. Most were trivial and would not disturb record linkage. Discrepancy rates of 7.1% in post code of residence at the time of diagnosis (excluding differences arising through boundary changes), 11.0% in anniversary date (excluding differences of 6 weeks or less), 7.7% in histological verification status, 5.4% in ICD-9 site codes (the first three digits) and 14.5% in ICD-O morphology codes (excluding 'inferred' morphology codes) were recorded. Overall, serious discrepancies were judged to have occurred in 2.8% of cases. In many respects, therefore, Scottish cancer registration data show a high level of accuracy that compares favourably to the reported accuracy of the few other cancer registries undertaking such analyses.

Comparison of artemether and chloroquine for severe malaria in Gambian children

Artemether is an oil-soluble methyl ether of artemesinin (qinghaosu). It has been studied extensively in China, where it has been shown to be rapidly effective in severe falciparum malaria. Nearly all the patients studied previously were adults. We have investigated the efficacy of artemether in children with moderate or severe falciparum malaria. In the preliminary study of moderately severe malaria, 30 Gambian children were randomised in pairs to receive either intramuscular artemether (4 mg/kg loading dose followed by 2 mg/kg daily) or intramuscular chloroquine ('Nivaquine') 3.5 mg base/kg every 6 h. Both drugs were well tolerated and rapidly effective. The times to parasite clearance were significantly shorter in the artemether recipients (mean 36.7 [SD 11.3] vs 48.4 [16.8] h, p less than 0.05). 43 children with severe malaria were then randomised to receive intramuscular treatment with the same regimens of artemether (n = 21) or chloroquine (n = 22) as used in the preliminary study. 8 children (19%) died. There were no significant differences between the two groups in the clinical, haematological, biochemical, or parasitological measures of therapeutic response in survivors and there was no evidence of local or systemic toxicity. Despite similar parasite counts on admission, clearance times overall were longer in severe malaria than in moderate malaria. Artemether is a well tolerated and rapidly effective parenteral treatment for severe malaria in children, and would be especially valuable in areas with chloroquine-resistant P falciparum.

Intracranial pressure in childhood cerebral malaria

Lumbar punctures were performed in 40 Gambian children with acute cerebral malaria aged between 18 months and 10 years. The mean opening pressure was elevated in 32 (80%) of the children, but was not significantly different in the 14 fatal cases compared with survivors: 110 (standard deviation 71) versus 131 (58) mm of cerebrospinal fluid respectively. Cerebral perfusion pressures were also similar in the 2 groups: 64 (20) mm Hg versus 64 (11) mm Hg respectively. There was no clear clinical evidence of raised intracranial pressure, and no evidence of deterioration immediately following lumbar puncture. Nevertheless brain swelling, and consequent brain-stem compression, may contribute to a fatal outcome in cerebral malaria--particularly in those children who die from sudden respiratory arrest. A prospective evaluation of osmotic agents in childhood cerebral malaria seems to be justified.

Open comparison of intramuscular chloroquine and quinine in children with severe chloroquine-sensitive falciparum malaria

An open paired randomised comparison of intramuscular chloroquine (3.5 mg base/kg every 6 h) and intramuscular quinine (20 mg salt/kg followed by 10 mg/kg every 12 h) was carried out in 50 Gambian children with severe falciparum malaria. 8 children died, 6 from the quinine-treated and 2 from the chloroquine-treated group. Chloroquine reduced parasitaemia significantly more rapidly than did quinine, but other measures of the therapeutic response were similar in the two groups. Quinine injections were painful. These findings do not support the proposition that quinine is intrinsically superior to chloroquine in the treatment of severe drug-sensitive falciparum malaria.

Electrocardiographic monitoring in severe falciparum malaria

Electrocardiographic monitoring over 24 h was performed with 53 patients with severe Plasmodium falciparum malaria (11 adults and 42 children) to assess the frequency of unrecognized cardiac arrhythmias. Nine patients (17%) died, 5 during the monitoring period and 4 afterwards. Pauses lasting 2-3 s were observed in 3 children, a single couplet in one, and a further child experienced frequent supraventricular ectopic beats which had not been detected clinically. In none of the patients who died could death be attributed to cardiac arrhythmia. Furthermore, no abnormality was detected which could have resulted from the often large doses of quinine, chloroquine or the artemisinin derivatives used for treatment. These results suggest that the heart is remarkably resilient even in the face of heavy parasite sequestration and other vital organ dysfunction, and that deaths from cardiac arrhythmias in severe malaria are rare. The need for routine cardiac monitoring of patients with severe and complicated P. falciparum malaria is questionable.

An evaluation of different ibuprofen preparations in the control of postoperative pain after third molar surgery

1. Two separate placebo-controlled studies of parallel design were carried out to evaluate the efficacy of single doses (400 mg) of soluble ibuprofen, ibuprofen liquid in a gelatin capsule and ibuprofen tablets (Nurofen), in patients with postoperative pain after third molar surgery. 2. All ibuprofen preparations provided significant pain relief (P less than 0.05) over a 6 h investigation period. 3. Mean pain scores after ibuprofen tablets and ibuprofen liquid in a gelatin capsule were similar. 4. Soluble ibuprofen 400 mg provided an earlier onset of pain relief (20 min) than ibuprofen tablets (30 min). 5. No unwanted effects were reported in the various ibuprofen treatment groups. 6. The ibuprofen preparations evaluated in this study are effective up to 4 h for controlling postoperative pain after third molar surgery. The soluble form is more efficacious with regard to onset of action.

The systemic availability of buprenorphine administered by nasal spray

The kinetics and systemic bioavailability of intranasally administered buprenorphine have been investigated in 9 healthy volunteers in an intranasal/intravenous cross-over study. Each subject received a nominal 0.3 mg dose of buprenorphine intranasally followed one week later by a matched dose intravenously. For the intranasal administration mean tmax and mean Cmax were 30.6 min and 1.77 ng mL-1, respectively. Mean intranasal bioavailability was 48.2 +/- 8.35% (mean +/- s.e.m.) of the intravenous value. Intranasal administration may represent a valuable new delivery route for buprenorphine.

Difficult airway management algorithms: a directed review

The primary aim of this study was to identify, describe and compare the content of existing difficult airway management algorithms. Secondly, we aimed to describe the literature reporting the implementation of these algorithms. A directed search across three databases (MEDLINE, Embase and Scopus) was performed. All articles were screened for relevance to the research aims and according to pre-determined exclusion criteria. We identified 38 published airway management algorithms. Our results show that most facemask employ a four-step process as represented by a flow chart, with progression from tracheal intubation, facemask ventilation and supraglottic airway device use, to a rescue emergency surgical airway. The identified algorithms are overwhelmingly similar, yet many use differing terminology. The frequency of algorithm publication has increased recently, yet adherence and implementation outcome data remain limited. Our results highlight the lack of a single algorithm that is universally endorsed, recognised and applicable to all difficult airway management situations.

Sequence analysis of HLA-Bw53, a common West African allele, suggests an origin by gene conversion of HLA-B35

In the West African population of the Gambia the class I antigen HLA-Bw53 is found at high frequency. We used the polymerase chain reaction to amplify cDNA from an individual homozygous for this allele and determined the nucleotide sequence of the polymorphic alpha 1 and alpha 2 domains. The HLA-Bw53 sequence is identical to HLA-B35 except for a short sequence at the 3' end of exon 2 (encoding the alpha 1 domain) which specifies a Bw4 rather than a Bw6 motif. This suggests an origin for HLA-Bw53 involving a gene conversion of HLA-B35 by an allele containing this Bw4 sequence. The alpha 2 domain shared by HLA-Bw53, -B35, and -Bw58 is particularly common in sub-Saharan Africans.

The pharmacokinetic properties of intramuscular quinine in Gambian children with severe falciparum malaria

Plasma quinine concentrations were measured in 21 Gambian children with severe falciparum malaria after intramuscular administration of a 20 mg (salt) per kg loading dose of quinine dihydrochloride followed by 10 mg/kg at 12 h intervals. Quinine was well absorbed reaching mean peak concentrations of 15.6 (standard deviation [SD] 4.5) mg/litre in a median time of 3 h (range 1-6 h). A one compartment model was fitted to the plasma concentration-time profile. The mean estimated systemic clearance (Cl/F) was 0.89 (SD 0.81) ml/kg/min and the mean elimination half life was 18.8 (SD 8.0) h. Two patients, one of whom died, had low plasma quinine levels which remained below 10 mg/litre. Mean peak and trough plasma concentrations after subsequent intramuscular doses ranged between 11.1 and 15.1 mg/litre. In most cases this dose regimen provided a satisfactory profile of blood concentrations for the treatment of severe malaria in children.

Thyrotropin-releasing hormone (TRH) analogues show enhanced CNS selectivity because of increased biological stability

TRH exerts both endocrinological and neuropharmacological actions. Two analogues of TRH, Pyr-His-Mep . NH2 (L-trans-3-methylprolineamide) and Pyr-His-Dmp . NH2 (L-3,3-dimethylprolineamide) have been examined for their neuropharmacological and endocrinological effects. Comparisons of their ability to provoke hyperthermia in rabbits demonstrated that both analogues were more potent than TRH, but like the parent peptide had only a limited ability to cross the blood brain barrier. This conclusion was confirmed by whole body autoradiographical studies. In contrast both analogues had a similar potency to TRH with respect to the ability to provoke TSH release. It is concluded that the increased potency in neuropharmacological tests results from enhanced bioavailability to CNS sites and that a similar rationale can be used to explain the CNS selectively claimed in the literature for other analogues of TRH.

Efficacy of tepid sponging versus paracetamol in reducing temperature in febrile children

A block randomized clinical trial to compare the efficacy of tepid sponging with the use of paracetamol in febrile children was undertaken at the Queen Elizabeth Central Hospital, Blantyre. Eighty children aged between 6 and 54 months with axillary temperatures of between > or = 38.5 degrees C and < or = 40 degrees C and a clinical diagnosis consistent with upper respiratory tract infection and/or malaria were block randomized to receive either oral paracetamol (15 mg/kg) or tepid sponging. Children receiving tepid sponging were sponged from head to toe (except the scalp) by leaving a thin layer of water on the body. If the body became dry it was repeated and continued until the axillary temperature fell to < 38.5 degrees C. Axillary temperature and assessment of discomfort (convulsions, crying, irritability, vomiting and shivering) were recorded every 30 minutes for 2 hours. A significantly greater and more rapid reduction of fever was demonstrated with paracetamol than with tepid sponging. Tepid sponging without antipyretics is often used to reduce fever, but our results suggest that this is effective only during the 1st 30 minutes. Paracetamol is clearly more effective than tepid sponging in reducing body temperature in febrile children in a tropical climate.

Modification of the proline residue of TRH enhances biological activity and inhibits degradation

An analogue of TRH with a modified proline residue (Pyr-His-MepNH2) has been synthesised and evaluated. In CNS, but not endocrine tests the analogue had improved activity compared to TRH and was more resistant to enzymatic degradation. A metabolite of TRH, His-Pro, was without biological activity. It is concluded that the biological actions attributed to TRH are due to the parent tripeptide rather than His-Pro and that these actions can be enhanced by improving the biological stability of TRH.

Herbal poisoning: a case report of a fatal yellow oleander poisoning from the Solomon Islands

A fatal yellow oleander herbal poisoning is reported in a 2 1/2-year-old Melanesian boy, who had persistent vomiting,bradycardia caused by complete heart block, hyperkalemia and cardiac glycosides detected in his serum. This is one of the few recognized clinical pictures of illness from herbal poisoning, yet herbal poisoning in infants in some Pacific and African countries is common and has a high mortality.