Thrombolytic potency of acid-stabilized plasmin: superiority over tissue-type plasminogen activator in an in vitro model of catheter-assisted thrombolysis

Plasmin, the direct fibrinolytic enzyme, was compared with tissue plasminogen activator (t-PA) in an in vitro thrombolysis model. Plasmin has been prepared in a highly pure form from human plasma and has been stabilized against auto-degradation by low-pH formulation. This acidified formulation of plasmin has been designed to have a low buffering capacity so that it can be directly infused into clots in a stable and latently active form. This low-pH formulation has been shown to be equivalent to a neutral-pH formulation of plasmin in its extent of clot lysis. An in vitro model of catheter-assisted thrombolysis has been devised in which large (12 x 0.6 cm), retracted clots are treated with an intrathrombus thrombolytic agent via a multi-sideport catheter. Plasmin dissolves these plasminogen-deficient clots in a dose-dependent manner and is clearly superior to t-PA. In this model system, t-PA exhibits efficacy only when retracted clots are replenished with plasminogen.

Meeting the challenge of prescribing and administering medicines safely: structured teaching and assessment for final year medical students

OBJECTIVES

To promote safe prescribing and administration of medicines in the pre-registration house officer (PRHO) year through a programme of structured teaching and assessment for final year medical students.

DESIGN

Forty final year medical students from two medical schools were randomly allocated either to participate in a pharmacist facilitated teaching session or to receive no additional teaching. Teaching comprised five practical exercises covering seven skills through which students rotated in small groups. One month later, a random sample of 16 taught and 16 non-taught students participated in a nine-station objective structured clinical examination (OSCE) to assess the impact of the teaching.

SETTING

Manchester School of Medicine (MSM), and Kings College School of Medicine and Dentistry (KCSMD).

PARTICIPANTS

Final year medical student volunteers.

MAIN OUTCOME MEASURES

The need for teaching as indicated by student prior experience; questionnaire rating of student acceptability of teaching and assessment; self-rating of student confidence post-assessment, and student performance assessed by OSCE.

RESULTS

The study demonstrated that the taught group achieved higher scores in eight OSCE stations. Four of these were statistically significant (P < or= 0.005). Taught students felt more confident performing the skills on five stations. From 0 to 47.5% students had prior experience of the skills taught. The post-teaching questionnaire evaluated exercises positively on several criteria, including provision of new information and relevance to future work.

CONCLUSIONS

Structured teaching provided an effective and acceptable method of teaching the medicines management skills needed in the PRHO year. The structured approach complemented variable precourse clinical experience.

Validation of four different risk stratification systems in patients undergoing off-pump coronary artery bypass surgery: a UK multicentre analysis of 2223 patients

BACKGROUND

Various risk stratification systems have been developed in coronary artery bypass graft surgery (CABG), based mainly on patients undergoing procedures with cardiopulmonary bypass.

OBJECTIVE

To assess the validity and applicability of the Parsonnet score, the EuroSCORE, the American College of Cardiology/American Heart Association (ACC/AHA) system, and the UK CABG Bayes model in patients undergoing off-pump coronary artery bypass surgery (OPCAB) in the UK.

METHODS

Data on 2223 patients who underwent OPCAB in eight cardiac surgical centres were collected. Predicted mortality risk scores were calculated using the four systems and compared with observed mortality. Calibration was assessed by the Hosmer-Lemeshow (HL) test. Discrimination was assessed using the receiver operating characteristic (ROC) curve area.

RESULTS

30 of 2223 patients (1.3%) died in hospital. For the Parsonnet score the HL test was significant (p < 0.001) and the receiver operating characteristic curve (ROC) area was 0.74. For the EuroSCORE the HL test was also significant (p = 0.008) and the ROC area was 0.75. For the ACC/AHA system the HL test was non-significant (p = 0.7) and the ROC area was 0.75. For the UK CABG Bayes model the HL test was also non-significant (p = 0.3) and the ROC area was 0.81.

CONCLUSIONS

The UK CABG Bayes model is reasonably well calibrated and provides good discrimination when applied to OPCAB patients in the UK. Among the other three systems, the ACC/AHA system is well calibrated but its discrimination power was less than for the UK CABG Bayes model. These data suggest that the UK CABG Bayes model could be an appropriate risk stratification system to use for patients undergoing OPCAB in the UK.

Knowledge of female bladder care among medical staff, nurses and midwives: results of a questionnaire survey

OBJECTIVE

To determine knowledge about bladder care among junior medical staff and allied health professionals, and to examine any difference in knowledge among the subgroups.

SUBJECTS AND METHODS

Using a single-questionnaire survey in a large obstetrics and gynaecology Hospital Trust in an inner city setting, midwives, nurses and medical staff (not consultants) were asked eight questions about different aspects of female bladder physiology and care. The differences in responses among the professional groups were assessed.

RESULTS

In all, 120 completed questionnaires were returned (32 doctors, 40 nurses, and 48 midwives). Knowledge was similar on urethral length, bladder capacity, daily fluid intake, ideal size of catheter, catheter balloon size, and the maximum time of use of a short-term catheter. Correct responses for normal daily fluid intake, duration of both short and long-term catheterization were given by fewer than half the respondents. There were significant differences among the professional groups in the correct response rate for long-term catheter duration (P = 0.031) and the normal time interval between voids (P = 0.038).

CONCLUSION

There were significant differences in the knowledge of all subgroups about bladder care, and poor levels of knowledge in several areas. This is a potentially serious problem for women at risk of bladder complications after gynaecological surgery and childbirth. All staff involved in managing women after childbirth and gynaecological surgery should have formal training in bladder care, to optimize patient care.

Field study of the efficacy of three types of nose net for the treatment of headshaking in horses

Thirty-six owners of seasonally headshaking horses took part in a trial to compare the effectiveness of three types of nose net, a traditional cylindrical net (full net) and two forms of larger mesh nets which cover only the nostrils and dorsorostral muzzle (half nets). Baseline data relating to the overall severity of the problem and 18 specific behaviours describing the nature of the problem were recorded on a check sheet by the owners. A within-subjects repeated measures design experiment, with each net used for a week before reassessment, was then used to assess the effect of the nets on the headshaking problem. Approximately 75 per cent of owners reported some overall improvement with each net; around 60 per cent recorded a 50 per cent or greater improvement and 30 per cent a 70 per cent or greater improvement. The nets significantly reduced the overall headshaking score and the following specific behaviours: up-and-down headshaking, nose flipping, acting as if a bee had flown up the nose, shaking at exercise, shaking when excited, shaking in bright sunlight or in windy conditions (P < 0.0001), striking at the face, shaking at night, rubbing the nose when moving, rubbing the nose on objects, sneezing, shaking in the rain and shaking indoors (P < 0.05). There was no evidence of a significant effect on side-to-side headshaking, shaking at rest or rubbing the nose when stationary, but the effect on snorting was uncertain. There were few significant differences between the nets, but the half nets were reported to be significantly better at controlling 'bee up the nose' behaviour. Horses more than 10 years old were reportedly less likely to show a 50 per cent or greater improvement in 'nose flipping' and 'headshaking at exercise.

Multicentre study comparing aggressive behaviour of familial non-medullary thyroid carcinoma and sporadic thyroid cancer

Background

Familial non-medullary thyroid cancer represents about 5 per cent of all thyroid cancers of follicular cell origin. Whether familial non-medullary thyroid cancer is more aggressive than sporadic thyroid cancer is controversial.

Methods

Each patient with familial non-medullary thyroid cancer was matched with three controls for age, sex and tumour node metastasis (TNM) stage of disease. Possible prognostic factors were compared in relation to recurrence, metastases and mortality rate in both groups. Univariate analysis was performed using contingency table analysis and McNemar's χ2 test for paired measurements. Multivariate analysis was used to evaluate factors significant in univariate analysis.

Results

Forty-eight cases (ten men) and 144 matched controls (30 men) were analysed with a mean follow-up of 102 and 94 months respectively. The mean age was 39 years for cases and 46 years for controls. Some 29 per cent of the cases and 12 per cent of the controls had history of prior or coexistent benign thyroid disease (P &lt; 0·05). Ninety-four per cent of cases and 90 per cent of controls had papillary cancers; the remainder were Hurthle cell cancers. Based on TNM staging, there were 66 per cent stage I, 21 per cent stage II and 13 per cent stage III tumours in the familial non-medullary thyroid cancer group; the distribution was similar in the control group. Modified radical neck dissection was performed in 42 per cent of cases and 22 per cent of controls. Multifocal or bilateral disease was seen in 75 per cent of cases and 41 per cent of controls (P &lt; 0·05); 35 per cent of cases and 16 per cent of controls had at least one recurrence (P &lt; 0·05). Ten per cent of cases and 2 per cent of controls developed distant metastases (P &lt; 0·05). Six per cent of cases but no controls died from thyroid cancer (P &lt; 0·05). In patients with familial non-medullary thyroid cancer aged over 45 years (n = 14), distant metastases affected four, of whom three died. In multivariate analysis, age was the only significant variable that affected the disease outcome (P &lt; 0·01).

Conclusion

Familial non-medullary thyroid cancer is more aggressive than sporadic thyroid cancer and is associated with increased recurrence, metastasis and death, especially in patients over 45 years of age.

Importance of emergency identification schemes

BACKGROUND

Millions of people worldwide may have a hidden medical condition that could endanger their life in an emergency. These conditions may include cardiac conditions, severe allergies, or diabetes. Emergency identification schemes such as Medic Alert produce emblems that alert health care professionals to potential problems and can ensure appropriate and prompt treatment. This paper uses mechanical failure of the Björk-Shiley convexo-concave (BSCC) heart valve as an example of a hidden medical condition. These patients have been encouraged to carry information to alert staff in an emergency that they have a BSCC patient in their care and to be alert to the signs and symptoms of acute valve malfunction.

OBJECTIVE

To establish awareness and credibility of emergency identification schemes among emergency personnel and to assess if information on specific medical conditions would influence ambulance personnel regarding destination hospitals.

METHODS

Questionnaires were sent to senior staff (n=380) of accident and emergency (A&E) departments and operational directors of ambulance headquarters (n=39) throughout the United Kingdom. Hospitals were divided into regional divisions to assess differences in responses across regions.

RESULTS

The majority of respondents (99%) had heard of emergency identification schemes and felt that it was important for patients with special conditions to carry some form of identification. Nearly all ambulance respondents (97%) indicated it was routine to search for body worn emblems in contrast with only 71% of A & E staff. However, more than half of ambulance respondents (53.9%) stated information on emblems/cards would not influence their choice of destination hospital.

CONCLUSIONS

The importance of how information on pre-existing medical conditions can influence care, is highlighted by the BSCC valve issue, where immediate diagnosis is essential for patient survival. It is vital that all staff routinely search patients for this information and if necessary act upon the information provided.

Sequence of Plasmodium falciparum chromosomes 1, 3-9 and 13

Since the sequencing of the first two chromosomes of the malaria parasite, Plasmodium falciparum, there has been a concerted effort to sequence and assemble the entire genome of this organism. Here we report the sequence of chromosomes 1, 3-9 and 13 of P. falciparum clone 3D7--these chromosomes account for approximately 55% of the total genome. We describe the methods used to map, sequence and annotate these chromosomes. By comparing our assemblies with the optical map, we indicate the completeness of the resulting sequence. During annotation, we assign Gene Ontology terms to the predicted gene products, and observe clustering of some malaria-specific terms to specific chromosomes. We identify a highly conserved sequence element found in the intergenic region of internal var genes that is not associated with their telomeric counterparts.

Researching the experience of kidney cancer patients

The author's personal experience as a kidney cancer patient, researcher and founder of a kidney cancer support group forms the basis for consideration of the challenges involved in researching patients' experiences. The researcher needs to understand the variability of those experiences in both clinical and psychological-emotional terms, and in relation to the personal, familial and social contexts of the patient. It is also essential to define the purpose of the research and to show how an understanding of personal experiences of cancer can be used to enhance the quality of care for cancer patients. The research encounter with a patient is also in some respects a therapeutic encounter requiring a considerable degree of sensitivity on the part of the researcher. The person-centred approach of Carl Rogers is of value in supporting such an encounter.

New upper limit on the total neutrino mass from the 2 degree field galaxy redshift survey

We constrain f(nu) identical with Omega(nu)/Omega(m), the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2 Degree Field Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos, and a cosmological constant. Adding constraints from independent cosmological probes we find f(nu)<0.13 (at 95% confidence) for a prior of 0.1<Omega(m)<0.5, and assuming the scalar spectral index n=1. This translates to an upper limit on the total neutrino mass m(nu,tot)<1.8 eV for "concordance" values of Omega(m) and the Hubble constant.

Complete genome sequence of the model actinomycete Streptomyces coelicolor A3(2)

Streptomyces coelicolor is a representative of the group of soil-dwelling, filamentous bacteria responsible for producing most natural antibiotics used in human and veterinary medicine. Here we report the 8,667,507 base pair linear chromosome of this organism, containing the largest number of genes so far discovered in a bacterium. The 7,825 predicted genes include more than 20 clusters coding for known or predicted secondary metabolites. The genome contains an unprecedented proportion of regulatory genes, predominantly those likely to be involved in responses to external stimuli and stresses, and many duplicated gene sets that may represent 'tissue-specific' isoforms operating in different phases of colonial development, a unique situation for a bacterium. An ancient synteny was revealed between the central 'core' of the chromosome and the whole chromosome of pathogens Mycobacterium tuberculosis and Corynebacterium diphtheriae. The genome sequence will greatly increase our understanding of microbial life in the soil as well as aiding the generation of new drug candidates by genetic engineering.

Central nervous system prophylaxis in haematological malignancies

Given the poor prognosis of central nervous system (CNS) involvement in haematological malignancies, management is directed towards prevention. CNS prophylaxis may take the form of intrathecal therapy, cranial irradiation, systemic therapy or some combination of these. The toxicity of these methods is an important consideration. A risk-orientated approach to the delivery of CNS prophylaxis in each disorder is required.

Analysis of the variations in clinical signs shown by 254 cases of equine headshaking

A national survey of headshaking in 254 horses was undertaken to describe the clinical signs of the condition as observed by horse owners. Principal component analysis was used to determine the underlying structure of 11 signs and the criteria by which the affected horses could be most effectively differentiated; the analysis suggested five components with a variance greater than one which together explained over 60 per cent of the total variance. Other analyses of the data indicated that headshaking could develop at any age and that twice as many males were affected as females; 64 per cent of the horses shook their heads seasonally and geldings were more likely than mares to be seasonally affected. Seasonal headshaking tended to be significantly worse on sunny days but improved on rainy days, windy days, at night and indoors.

The genome sequence of Schizosaccharomyces pombe

We have sequenced and annotated the genome of fission yeast (Schizosaccharomyces pombe), which contains the smallest number of protein-coding genes yet recorded for a eukaryote: 4,824. The centromeres are between 35 and 110 kilobases (kb) and contain related repeats including a highly conserved 1.8-kb element. Regions upstream of genes are longer than in budding yeast (Saccharomyces cerevisiae), possibly reflecting more-extended control regions. Some 43% of the genes contain introns, of which there are 4,730. Fifty genes have significant similarity with human disease genes; half of these are cancer related. We identify highly conserved genes important for eukaryotic cell organization including those required for the cytoskeleton, compartmentation, cell-cycle control, proteolysis, protein phosphorylation and RNA splicing. These genes may have originated with the appearance of eukaryotic life. Few similarly conserved genes that are important for multicellular organization were identified, suggesting that the transition from prokaryotes to eukaryotes required more new genes than did the transition from unicellular to multicellular organization.

Dyslexia and familial high blood pressure: an observational pilot study

BACKGROUND

Developmental dyslexia is a neurodevelopmental learning disability characterised by unexpectedly poor reading and unknown aetiology. One hypothesis proposes excessive platelet activating factor, a potent vasodilator, as a contributor, implying that there should be a negative association between dyslexia and high blood pressure (HBP). Since both conditions have a partial genetic basis, this association may be apparent at the familial level.

AIMS

To test this prediction in dyslexic and non-dyslexic children.

METHODS

Individuals and families with (HBP+) and without (HBP-) a family history of HBP were compared.

RESULTS

Proportionately fewer dyslexics (49/112) than controls (11/12) were HBP+. Families with multiple, all dyslexic children were less likely to be HBP+ (7/16) than those with a non-dyslexic child (11/11). Within families, mean child scores on reading were higher in the HBP+ group (mean 44.3, SE 0.95) than in the HBP- group (mean 40.3, SE 0.87).

CONCLUSION

HBP+ family history is associated with better performance on reading. The prediction of a negative association between dyslexic status and familial high blood pressure is therefore confirmed.

The t(8;22) in chronic myeloid leukemia fuses BCR to FGFR1: transforming activity and specific inhibition of FGFR1 fusion proteins

This report describes 2 patients with a clinical and hematologic diagnosis of chronic myeloid leukemia (CML) in chronic phase who had an acquired t(8;22)(p11;q11). Analysis by fluorescence in situ hybridization (FISH) and reverse transcription-polymerase chain reaction (RT-PCR) indicated that both patients were negative for the BCR-ABL fusion, but suggested that the BCR gene was disrupted. Further FISH indicated a breakpoint within fibroblast growth factor receptor 1 (FGFR1), the receptor tyrosine kinase that is known to be disrupted in a distinctive myeloproliferative disorder, most commonly by fusion to ZNF198. RT-PCR confirmed the presence in both cases of an in-frame messenger RNA fusion between BCR exon 4 and FGFR1 exon 9. Expression of BCR-FGFR1 in the factor-dependent cell line Ba/F3 resulted in interleukin 3-independent clones that grew at a comparable rate to cells transformed with ZNF198-FGFR1. The growth of transformed cells was inhibited by the phosphatidylinositol 3-kinase inhibitor LY294002, the farnesyltransferase inhibitors L744832 and manumycin A, the p38 inhibitors SB202190 and SB203580 but not by the MEK inhibitor PD98059. The growth of BaF3/BCR-FGFR1 and BaF3/ZNF198-FGFR1 was not significantly inhibited by treatment with STI571, but was inhibited by SU5402, a compound with inhibitory activity against FGFR1. Inhibition with this compound was associated with decreased phosphorylation of ERK1/2 and BCR-FGFR1 or ZNF198-FGFR1, and was dose dependent with an inhibitory concentration of 50% of approximately 5 microM. As expected, growth of BaF3/BCR-ABL was inhibited by STI571 but not by SU5402. The study demonstrates that the BCR-FGFR1 fusion may occur in patients with apparently typical CML. Patients with constitutively active FGFR1 fusion genes may be amenable to treatment with specific FGFR1 inhibitors.

The relationship between Helicobacter pylori infection, the virulence genotypes of the infecting strain and gastric cancer in the African setting

BACKGROUND

The relationship between Helicobacter pylori infection and gastric carcinoma remains controversial, especially in the African setting where infection is common, while gastric cancer is perceived to be uncommon, the basis of the so called 'African enigma'. This discrepancy between infection and the development of disease is commonly attributed to differences in host, environment and bacterial factors. Interest in the bacterial factors has focused on heterogeneity in the so-called 'virulence genes'.

AIM

The aim of this prospective, case-controlled study was to establish whether H. pylori infection is significantly associated with gastric cancer and to investigate whether gastric cancer is associated with genotypically distinct (as it relates to the candidate virulence genes) organisms in this population.

METHODS

Patients with histologically confirmed gastric cancer were matched with nonulcer dyspeptic controls for age (within 5 years), gender and ethnicity. Helicobacter pylori status was determined by RUT, histology, culture and serology (locally validated and used as default determinant of H. pylori status). Tumors were classified according to the Lauren classification. The 'virulence genotype' of 17 paired culture samples was determined by previously described and validated molecular techniques (cagA presence, vacA alleles, structure of the cag pathogenicity island and analysis of the iceA alleles). Categorical variables were analysed by the chi2 test.

RESULTS

Forty-eight patients (median age 59 years) could be adequately matched to controls. 39/48 (81%) cases and 43/48 (90%) controls were H. pylori positive (NS). Significant differences in the virulence genotypes of infecting strains were noted: vacAs2-controls 24%, cases 0%, p < .00001; vacAs1 present - cases 100%, controls 76%, p < .05; cagA-3'-length > 650 bp - cases 47%, controls 0%, p < .002; cag pathogenicity island intact - cases 82%, controls 43%, p < .04; iceA1 - cases 53%, controls 6%, p < .005. cagA was found in all subjects.

CONCLUSION

This study indicates that, in this African population at least, there is no difference in the prevalence of H. pylori infection when comparing gastric cancer cases with matched controls. However, the findings suggest that gastric cancer may be associated with infection by organisms that are genotypically different from those not associated with disease.

Angioedema in the emergency department: a presentation of lymphoma

A 58-year-old woman presented to emergency departments on several occasions with episodic angioedema. Lymphoplasmacytic lymphoma with an IgM paraprotein (Waldenstrom's macroglobulinemia) was eventually diagnosed 14 months later in association with acquired C1 esterase inhibitor deficiency. Resolution of the angioedema and C1 esterase inhibitor deficiency was achieved with danazol and treatment of the underlying lymphoma.