Clinical response to morphine in cancer patients and genetic variation in candidate genes

Morphine is the analgesic of choice for moderate to severe cancer pain; however, 10-30% of patients do not tolerate morphine. This study evaluated genetic variation in the mu-opioid receptor, betaarrestin2, stat6 and uridine diphosphate-glucuronysltransferase 2B7 (UGT2B7) genes, in patients who responded to morphine vs those who were switched to alternative opioids. We prospectively recruited and genotyped 162 Caucasian patients (117 controls, 39 switchers). Switchers, were more likely to carry the common allele at 1182 G/A, 5864 G/A, 8622T/C and 11143 G/A in the betaarrestin2 gene (P = 0.021, 0.043, 0.013, 0.043, respectively). Switchers had increased carriage of the T allele (-1714 C/T) and a significant difference in the allelic frequency at 9065 C/T (chi(2) = 3.86, P = 0.049) in the stat6 gene. No differences were seen in genotype or allele frequencies of SNPs in the mu-opioid receptor gene or UGT2B7 gene. This study presents novel data suggesting that variation in genes involved in mu-opioid receptor signalling influence clinical response to morphine.

A retrospective study of the association between haematological and biochemical parameters and morphine intolerance in patients with cancer pain

BACKGROUND

Morphine is the strong opioid of choice for the treatment of moderate to severe cancer pain according to guidelines of the World Health Organization (WHO). However, a minority of patients do not receive the desired analgesic effect or suffer intolerable side effects from morphine, and are switched to alternative opioids.

METHODS

The aim of this retrospective study was to identify factors that might be associated with morphine intolerance. Data were analysed from 100 controls who tolerated morphine and 77 patients who were switched to an alternative opioid. We investigated whether currently logged data could fully explain the need to switch. Demographic details, cancer type (histological diagnosis) and markers related to organ function were included in an analysis of biochemical and haematological parameters.

RESULTS

Patients over 78 years (P = 0.03), or with a high white cell (P = 0.002) or high platelet count (P = 0.003), were more likely to switch. Although our numbers were small, patients with severe organ impairment were more likely to switch. However, a model including white cell count, platelet count, age, serum albumin and alkaline phosphatase, accurately separated switchers and controls in only 68% of cases. There was no significant difference between the two groups in terms of the numbers of patients having cytotoxic drugs in the two weeks prior to the haematological and biochemical analysis. Similarly, there were no significant differences in histological diagnoses between groups.

CONCLUSIONS

The white cell count was the strongest single effect observed and, as such, warrants further investigation. Further studies are needed in order to accurately define a model that will predict those patients likely to be intolerant of morphine.

Redescription of Diesingia megastoma (Diesing, 1836) Sambon, 1922, a pentastomid parasite from the South American terrapin Hydromedusa tectifera Cope

Slide-mounted material of the pentastomid parasite Diesingia megastoma (Diesing, 1836) Sambon, 1922 from the South American chelonian Hydromedusa tectifera Cope is reviewed and the perfunctory, often omissive, description of the species is amended. The strong morphological similarities between D. megastoma and the crocodilian and chelonian pentastome genera of the family Sebekiidae Sambon, 1922, Alofia Giglioli, 1922, Selfia Riley, 1994, Sebekia Sambon, 1922, Agema Riley, Hill & Huchzermeyer, 1997, Leiperia Sambon, 1922 and Pelonia Junker & Boomker, 2002, clearly place Diesingia Sambon, 1922 within the same family. However, the unique combination of its main diagnostic criteria makes Diesingia a distinct genus. The absence of an elaborate, flared cirrus-tip in D. megastoma distinguishes it from Leiperia, while emphasizing its similarity to the remaining genera mentioned above. D. megastoma resembles Alofia in that it possesses smooth, flat-topped hooks and an anteriorly open oral cadre with an oesophageal peg. The copulatory spicules of Diesingia, however, lack the double-hooked collar, typical for Alofia and Selfia. Unlike the peg-like extension of the fulcra of the hooks of Sebekia, that of D. megastoma is cowl-like and carries spines only on the anterior fulcra. Moreover, the hooks of Sebekia are usually convex and spinose and the ovoid oral cadre is closed anteriorly. Diesingia differs from Pelonia through the latter's smooth but dorsally convex and extension-free hooks. The copulatory spicules of Pelonia and Agema are reminiscent of the basic build found in Sebekia, whereas in D. megastoma the short, ventral extension of the cowry shell-shaped base of the copulatory spicules has been transformed into a structure resembling the collembolan fulcrum. The latter is connected to the base via a joint, a configuration which is unique in the Sebekiidae.

The use of prophylactic flucloxacillin in treatment of open fractures of the distal phalanx within an accident and emergency department: a double-blind randomized placebo-controlled trial

Open fractures of the distal phalanx commonly present to the Accident and Emergency Department. Controversy surrounds the use of prophylactic antibiotics in treating this injury. A double-blind, prospective, randomized placebo-controlled study was undertaken comparing the use of prophylactic flucloxacillin to placebo in addition to meticulous wound toilet. One hundred and ninety-three adult patients with an open fracture of the distal phalanx were studied. Seven patients developed superficial infections, an overall infection rate of 4%. No patient developed osteitis or a deep wound infection. There were three cases of infection in the 98 patients (3%) in the antibiotic group and four cases of infection in the 95 patients (4%) in the placebo group. A difference of proportion test confirmed no significant difference. It is concluded that the addition of prophylactic flucloxacillin to thorough wound toilet and careful soft-tissue repair of open fracture of the distal phalanx confers no benefit.

Raillietiella trachea n. sp., a pentastomid from the trachea of an oriental white-backed vulture Gyps bengalensis taken in Pakistan, with speculation about its life-cycle

A cephalobaenid pentastomid, Raillietiella trachea n. sp., from the trachea of a fledgling oriental white-backed vulture Gyps bengalensis taken in Punjab Province, Pakistan, is described. This is the first record of a pentastomid from a fully terrestrial bird. Overall, gross morphology was typical of Raillietiella Sambon, 1910 in most respects. However, the hooks of R. trachea were of equal size, whereas in other members of the genus anterior hooks are smaller than the posterior hooks. The diagnosis of R. trachea was made on the basis of four near-patent females, all of which contained relatively few eggs (c.570), all at the same stage of maturity. Comparison with the only other genus known to infect birds (two species of Reighardia Ward, 1899 from the air-sacs of marine birds) revealed striking parallels in this aspect of the functional anatomy of the female reproductive tract. As far as we know, this mode of egg-production is not found in other raillietiellids. Extrapolating primarily from the experimental life-cycle studies of Reighardia sternae (Diesing, 1864) Ward, 1899, we surmise that the life-cycle of R. trachea has to be direct and that parasite behaviour is an integral part of parasite transmission. The evidence suggests that transmission is from vulture-to-vulture, per os.

Planning for a good death: responding to unexpected events

When a terminally ill patient develops an acute problem, risky emergency treatment may seem futile to medical staff. But sometimes patients are not ready to die. What is a good death in such circumstances and how do we achieve it?

Did mothers begin with an advantage? A study of childbirth and maternal health in England and Wales, 1778-1929

This paper contributes to two ongoing debates among demographers. One deals with the immediate and deferred health effects of childbearing in the past, and the other with competing explanations--the frailty and insult accumulation hypotheses--for differences in individual health later in life. The study population consists of working women who lived at four locales in England and Wales in parts of the period 1778-1929 and who were under observation for incapacitating sickness during and after their childbearing years. Mothers within the study population are contrasted with a comparison group made up principally of non-mothers. The mothers began their reproductive careers with an advantage in health that was especially evident in the duration of sickness episodes. Even though individual births were less hazardous than individual sicknesses at the same ages, the cumulative effect of childbearing appears to have eroded the mothers' advantage. By ages 50-74 the mothers resembled the comparison group in health.

The nurse as expert practitioner in global cardiovascular risk management

Randomised controlled trials have demonstrated the benefit of nurse-run clinics for secondary prevention of coronary heart disease through impacting upon health perceptions and on cardiovascular risk factors. However, to achieve positive results, intensive intervention is needed and this requires a significant time commitment. At present, nurses tend to be involved in individualised interventions directed at patients who already have coronary heart disease. There is a need now to consider a community approach to prevention of cardiovascular disease. It is also important to try to influence the structural, economic, and cultural issues that are impacting upon cardiovascular risk management.

A method for generating patient-specific finite element meshes for head modelling

Finite element modelling of fields within the body, whether electrical or optical, requires knowledge of the geometry of the object being examined. It can be clinically impractical to obtain accurate surface information for individual patients, although a limited set of measurements such as the locations of sensors attached to the body, can be acquired more readily. In this paper, we describe how a generic surface taken from an adult head is warped to fit points measured on a neonatal head surface to provide a new, individual surface from which a finite element mesh was generated. Simulations show that data generated from this mesh and from the original neonatal head surface are similar to within experimental errors. However, data generated from a mesh of the best fit sphere were significantly different from data generated from the original neonatal head surface.

A post-marketing observational study to assess the safety of mibefradil in the community in England

OBJECTIVES

To conduct a post-marketing observational cohort study to assess the safety of mibefradil in the community, using Prescription-Event Monitoring (PEM).

METHOD

Data were collected and analyzed on patients prescribed mibefradil by 1,996 General Practitioners (GPs) throughout England. Incidence densities were calculated for all reported events and selected events were followed-up by means of further questionnaires.

RESULTS

The study was terminated early due to the voluntary withdrawal of mibefradil from the market because of potential drug interactions. A cohort of 3,085 patients was recruited, with a mean age of 64.5 years. The major indication for use was hypertension (55% of the cohort), the indication was not specified in 33% of patients. 80% of GPs expressing an opinion rated mibefradil as effective. The major reason for stopping was withdrawal from the market (2,342 patients). The commonest reported adverse events and reasons for stopping were malaise/lassitude, dizziness, edema and headache. Seven clinically serious reports of bradycardia/collapse were considered to be possible adverse drug reactions (ADRs) to mibefradil. All were in the elderly (> 65 years), 6 were considered to be a result of possible drug interactions. In total, 11 possible drug interactions occurred. Nine (8 reports of bradycardia and 1 of syncope) involved beta-blockers. Another, a report of collapse and severe bradycardia, occurred in a patient who had started a dihydropyridine calcium channel blocker within 24 hours of stopping mibefradil and the other was a report of palpitations and dyspnea in a patient on concomitant digoxin and sotalol. None of the 53 deaths occurring during the study was attributed to mibefradil.

CONCLUSION

Mibefradil was only available on the UK market for 6 months before it was withdrawn from the market because of potential drug interactions. With respect to the reasons leading to its withdrawal, in this cohort of 3,085 patients, 11 possible drug interactions were detected (6 clinically significant) involving beta-blockers, a dihydropyridine calcium channel blocker and digoxin and/or sotalol. PEM can contribute to the understanding of ADRs caused by drug interactions occurring in real-life settings.

Proteins and proteinases in the in vitro released products (IVRP) of the tissue-invasive and lung-dwelling larvae of the pentastomid Porocephalus crotali

Pentastomids are arthropod-like parasites which inhabit the respiratory tract of tetrapods and, despite being haematophagous, cause little or no visible pathology. Nymphs (or larvae), belonging to the advanced genus Porocephalus, encyst in the tissues of rodent intermediate hosts and migrate from this site to the lung following ingestion of the intermediate host. During migration, several moults occur and instars encounter a variety of tissue barriers and environmental cues. It was therefore relevant to define the proteins and proteinases released by the different instars during this migration as they are likely to be essential for tissue penetration, feeding and immune evasion. In vitro released proteins (IVRP), commonly termed ES, were defined on the basis of molecular size and immune recognition by naturally infected rodent intermediate hosts. In addition, proteinases present in IVRP were characterized using gelatin-substrate gels and protein degradation assays. These studies showed that the protein profile is subtly different when IVRP from different instars is compared. In addition, IVRP from each instar contained metallo-proteinases with proteolysis at 48 kDa dominating in all stages. However, other higher molecular weight activities were, to an extent, released in a stage-specific manner. These proteinases degraded haemoglobin and fibrinogen as well as structural proteins such as collagen and fibronectin, suggesting roles in bloodmeal digestion and tissue penetration. Immunoglobulin digestion was not demonstrated.

Prescription-event monitoring and reporting of adverse drug reactions

Newly marketed drugs in the UK are marked with a black triangle, indicating that doctors should report all adverse drug reactions associated with them to the Committee on Safety of Medicines (CSM). However, under-reporting of adverse reactions is frequent. Our aim was to establish what types of adverse reactions are under-reported to the CSM by family doctors who work in England. We used prescription-event monitoring data obtained for 15 newly marketed drugs. Only 9% (376) of 4211 events found on prescription-event monitoring were reported to the CSM. However, 53% (27) of 51 events classified as serious adverse drug reactions were reported. Overall, serious events were five times more likely to be reported to the CSM than non-serious events. Our results should not be extrapolated to calculate incidence rates of adverse drug reactions in the community from spontaneous reports.

Internal fixation of a displaced tibial sesamoid fracture

The authors present a surgical technique for the preservation and repair of an acutely fractured sesamoid using internal fixation of the sesamoid. A case report demonstrating the technique for the open reduction and internal fixation of a fractured tibial sesamoid is presented. The authors recommend this procedure as a viable alternative to surgical excision of the tibial sesamoid. The use of the procedure as an adjunct for the surgical treatment of recalcitrant traumatic sesamoiditis is also discussed.

Pentastomids and the tetrapod lung

Pentastomids comprise a highly specialized taxon of arthropod-like parasites that probably became adapted to the lungs of amphibians and reptiles early in their long evolutionary history. Few other macroparasites exploit this particular niche. Pentastomids are often large, long-lived and yet they cause little observable pathology in lungs, despite being haematophagous. The lungs of all tetrapods are lined with pulmonary surfactant, a remarkable biological material consisting of a complex mixture of phospholipids, neutral lipids and proteins that has the unique ability to disperse over the air-liquid lining of the lung. In the lower tetrapods it acts as an anti-glue preventing adhesion of respiratory surfaces when lungs collapse during swallowing prey or upon expiration. In mammals, pulmonary surfactant also plays a critical role regulating the activity of alveolar macrophages, the predominant phagocytes of the lower airways and alveoli. This review outlines the evidence suggesting that lung-dwelling pentastomids, and also nymphs encysted in the tissues of mammalian intermediate hosts, evade immune surveillance and reduce inflammation by coating the chitinous cuticle with a their own stage-specific surfactant. The lipid composition of surfactant derived from lung instars of the pentastomid Porocephalus crotali cultured in vitro is very similar to that recovered from the lung of its snake host. Pentastomid surfactant, visualised as lamellate droplets within sub-parietal cells, is delivered to the cuticle via chitin-lined efferent ducts that erupt at a surface density of < 400 mm(-2). The fidelity of the system, which ensures that every part of the cuticle surface is membrane-coated, testifies to its strategic importance. Two other extensive glands discharge membrane-associated (hydrophobic?) proteins onto the hooks and head; some have been purified and partly characterized but their role in minimising inflammatory responses is, as yet, undetermined.

Are red algae plants? A critical evaluation of three key molecular data sets

Whether red algae are related to green plants has been debated for over a century. Features present due to their shared photosynthetic habit have been interpreted as support for an evolutionary sisterhood of the two groups but, until very recently, characters endogenous to the host cell have provided no reliable indication of such a relationship. In this investigation, we examine three molecular data sets that have provided key evidence of a possible relationship between green plants and red algae. Analyses of an expanded alignment of DNA-dependent RNA polymerase II largest subunit sequences indicate that their support for independent origins of rhodophytes and chlorophytes is not the result of long-branch attraction, as has been proposed elsewhere. Differences in the pol II C-terminal domain, an essential component of plant mRNA transcription, also suggest different host cell ancestors for the two groups. In contrast, concatenated sequences of two groups of mitochondrial genes, those encoding subunits of NADH-dehydrogenase as well as cytochrome c oxidase subunits plus apocytochrome B, appear to cluster red algal and green plant sequences together because both groups have evolved relatively slowly and share a super-abundance of ancestral positions. Finally, analyses of elongation factor 2 sequences demonstrate a strong phylogenetic signal favoring a rhodophyte/chlorophyte sister relationship, but that signal is restricted to a contiguous segment comprising approximately half of the EF2 gene. These results argue for great caution in the interpretation of phylogenetic analyses of ancient evolutionary events but, in combination, indicate that there is no emerging consensus from molecular data supporting a sister relationship between red algae and green plants.

Gene expression and amplification in breast carcinoma cells with intrinsic and acquired doxorubicin resistance

The multidrug resistance (MDR) phenotype is a major cause of cancer treatment failure. Here the expressions of 4224 genes were analysed for association with intrinsic or acquired doxorubicin (DOX) resistance. A cluster of overexpressed genes related to DOX resistance was observed. Included in this cluster was ABCB1 the P-glycoprotein transporter protein gene and MMP1 (Matrix Metalloproteinase 1), indicative of the invasive nature of resistant cells, and the oxytocin receptor (OXTR), a potential new therapeutic target. Overexpression of genes associated with xenobiotic transformation, cell transformation, cell signalling and lymphocyte activation was also associated with DOX resistance as was estrogen receptor negativity. In all carcinoma cells, compared with HBL100 a putatively normal breast epithelial cell line, a cluster of overexpressed genes was identified which included several keratins, in particular keratins 8 and 18 which are regulated through the ras signalling pathway. Analysis of genomic amplifications and deletions revealed specific genetic alterations common to both intrinsic and acquired DOX resistance including ABCB1, PGY3 (ABCB4) and BAK. The findings shown here indicate new possibilities for the diagnosis of DOX resistance using gene expression, and potential novel therapeutic targets for pharmacological intervention.

A single point mutation in HIV-1 V3 loop alters the immunogenic properties of rgp120

The results of the study presented in this report show that clones of env derived from genetically divergent HIV-1 field isolates fall into two major subsets based on the predicted secondary structure of the V3 region in gp120. One subset exemplified by the clones A-UG06c, B-RT3.12 and C-UG045 is predicted to assume a beta-turn conformation in the V3 loop and comprises the GPGX residues. The other subset exemplified by the clones D-UG23c and D-UG042 (GXGX) are deficient in the expression of the beta-turn in the loop. Since secondary conformations are highly likely to confer antigenic properties in a protein backbone at least for B cells, we have used nucleic acid immunization to test the effect of the beta-turn deficiency on the immunogenic potential of rgp120 encoded in these field isolates. As hypothesized, inoculation of BALB/c mice with the env plasmid encoding the beta-turn expressing rgp120 molecules resulted in the development of a vigorous antibody response to the homologous V3 loop peptides. In contrast, immunization with an rgp120 clone deficient in the beta-turn in the V3 loop showed no evidence of antibody development to the V3 loop. Instead, the latter clones triggered T cell proliferative responses and markedly increased the level of IL-2 and IFN-gamma production by T cells. Significantly, reconstitution of the beta-turn conformation by site-directed mutagenesis of a single V3 loop residue yielded rgp120 molecules which restored antibody production while diminishing the cell-mediated immune (CMI) responses to the V3 residue. These observations demonstrate the marked impact of a single amino acid substitution on the immunogenic properties of V3 region in gp120 encoded by divergent HIV-1 field isolates.

Assessing and managing chronic heart failure

Patients with chronic heart failure have a reduced quality of life. Symptoms can be managed, but there is no cure. Heart failure nurses can offer advice, education and support to patients. This article reviews the common causes of heart failure and the nursing interventions that can help manage the symptoms.