The crayfish plasma clotting protein: a vitellogenin-related protein responsible for clot formation in crustacean blood

Coagulation in crayfish blood is based on the transglutaminase-mediated crosslinking of a specific plasma clotting protein. Here we report the cloning of the subunit of this clotting protein from a crayfish hepatopancreas cDNA library. The ORF encodes a protein of 1,721 amino acids, including a signal peptide of 15 amino acids. Sequence analysis reveals that the clotting protein is homologous to vitellogenins, which are proteins found in vitellogenic females of egg-laying animals. The clotting protein and vitellogenins are all lipoproteins and share a limited sequence similarity to certain other lipoproteins (e.g., mammalian apolipoprotein B and microsomal triglyceride transfer protein) and contain a stretch with similarity to the D domain of mammalian von Willebrand factor. The crayfish clotting protein is present in both sexes, unlike the female-specific vitellogenins. Electron microscopy was used to visualize individual clotting protein molecules and to study the transglutaminase-mediated clotting reaction. In the presence of an endogenous transglutaminase, the purified clotting protein molecules rapidly assemble into long, flexible chains that occasionally branch.

Management of coexisting coronary artery and asymptomatic carotid artery disease: report of a series of patients treated with coronary bypass alone

BACKGROUND

A retrospective chart review of 94 patients with asymptomatic high-grade carotid stenosis undergoing coronary bypass (and valve replacement in some cases) was performed to determine whether significant carotid lesions can be safely ignored in patients undergoing cardiac surgical procedures. These operations were performed during a 2-year period.

PATIENTS AND METHODS

There were 55 men and 39 women, with an age range of 37-89 years. Seventy-one patients had unilateral high-grade carotid stenosis, 17 patients had bilateral high-grade lesions, and six patients had unilateral high-grade stenosis and contralateral occlusion. Associated medical problems were recorded and short-term follow-up was obtained.

RESULTS

There was one perioperative stroke and no deaths in this group of patients.

CONCLUSIONS

Although these data indicate that high-grade carotid stenoses may be safely ignored during cardiac surgical procedures, a multicentre prospective randomized trial is needed to determine the appropriate treatment of the patient with coexisting carotid and coronary artery disease.

Measuring community/environmental interventions: the Child Pedestrian Injury Prevention Project

OBJECTIVES

To assess the effectiveness of community/environmental interventions undertaken as part of the Child Pedestrian Injury Prevention Project (CPIPP).

SETTING

Three communities (local government areas) in the Perth metropolitan area, Western Australia.

METHODS

A quasiexperimental community intervention trial was undertaken over three years (1995-97). Three communities were assigned to either: a community/environmental road safety intervention and a school based road/pedestrian safety education program (intervention group 1); a school based road/pedestrian safety education program only (intervention group 2); or to no road safety intervention (comparison group). Quantification of the various road safety community/environmental activities undertaken in each community during the trial was measured, and a cumulative community activity index developed. Estimates of the volume and speed of vehicular traffic were monitored over a two year period.

RESULTS

Greater road safety activity was observed in intervention group 1 compared with the other groups. A significant reduction in the volume of traffic on local access roads was also observed over the period of the trial in intervention group 1, but not in the remaining groups.

CONCLUSIONS

The findings indicate that the various community/environmental interventions initiated in collaboration with CPIPP in intervention group 1 contributed, in part, to the observed reduction in the volume of traffic. A combination of community/environmental interventions and education are likely to reduce the rate of childhood pedestrian injury.

Reduction of the occurrence of acute cellular rejection among renal allograft recipients treated with basiliximab, a chimeric anti-interleukin-2-receptor monoclonal antibody. United States Simulect Renal Study Group

BACKGROUND

A double-blind, placebo-controlled phase III study was performed to assess whether basiliximab, a chimeric anti-interleukin-2 receptor monoclonal antibody, reduced the incidence of acute rejection episodes in renal allograft recipients.

METHODS

A total of 348 patients were randomized into two demographically matched, equally sized groups treated with either basiliximab or placebo. The dose of basiliximab-20-mg infusions on day 0 and day 4-was selected to block detection of interleukin-2 receptor on 97% of peripheral blood lymphocytes for 30-45 days. All patients received immunosuppressive therapy with cyclosporine microemulsion (Neoral) and steroids. An intent-to-treat analysis of 1-year data assessed the incidence of posttransplant acute rejection episodes, patient and graft survival rates, and the safety and tolerability of basiliximab.

RESULTS

Among the eligible 346 patients equally divided into the two treatment groups, basiliximab reduced the proportion of patients who experienced biopsy-confirmed acute rejection episodes by 28%: 61 (35.3%) basiliximab vs. 85 (49.1%) placebo (P=0.009). Graft losses occurred in 9 (5.2%) basiliximab-treated and 12 (6.9%) placebo-treated patients. Five (2.9%) deaths in the basiliximab group and seven (4.0%) in the placebo group occurred. Compared with placebo, a higher fraction of basiliximab patients produced urine in the operating room, and a significantly lower fraction had renal dysfunction in the first month (serum creatinine > or =5 mg(dl) and between 1 and 12 months (serum creatinine > or =3 mg/dl). During the first 12 months, 94 (54%) basiliximab-treated patients experienced serious adverse events, compared with 106 (61%) who received placebo.

CONCLUSIONS

Prophylactic basiliximab therapy is well tolerated, has an adverse event profile comparable to placebo, and significantly reduces the number of acute rejection episodes in renal allograft patients within the first year after transplantation.

Trophic effects of cardiotrophin-1 and interleukin-11 on rat dorsal root ganglion neurons in vitro

Cardiotrophin-1 (CT-1) was originally isolated for its hypertrophy inducing effects on cardiac myocytes whereas interleukin-11 (IL-11) was identified due to its ability to stimulate an interleukin-6 (IL-6) dependent plasmocytoma cell line. Both cytokines are structurally and functionally related to a group of factors called neuropoietic cytokines, which also includes IL-6, ciliary neurotrophic factor (CNTF), leukemia inhibitory factor (LIF), and oncostatin M. These factors have trophic effects on subsets of neurons. In the present study we examined the influence of CT-1 and IL-11 on newborn rat dorsal root ganglion neuron survival in vitro. Mouse CT-1 showed prominent trophic effects that were comparable to those of CNTF and LIF. Mouse IL-11 alone did not enhance neuronal survival, but soluble mouse IL-11 receptor alpha rendered neurons sensitive to IL-11. Surprisingly, soluble IL-11 receptor alpha even had slight neurotrophic effects by itself. These results suggest that CT-1 and IL-11 might also be involved in the physiological regulation of sensory neuron survival. Thus, they might, like CNTF, become tools for the therapeutic intervention in neurodegeneration due to disease, toxicity, and trauma.

Turning down the jezebel decibels

SUMMARY According to conventional wisdom, many breakups are due to "the other woman" -the home wrecker who comes between perfectly contented lesbian partners. In this excerpt from The Lesbian Love Companion: How to Survive Everything from Heartthrob to Heartbreak, author Hall explores the fresh ways we might retell the traditional "other woman" tale. Also included in this excerpt are the benefits that accrue to monogamous and polyamorous lesbians who learn to tell such alternative stories.

Escherichia coli O157 incident associated with a farm open to members of the public

Three children, one who lived on an open farm and two who visited the farm in school parties, developed Vero cytotoxin producing Escherichia coli (VTEC) O157 infection in 1997. All had been in direct contact with animals. All were admitted to hospital with diarrhoea and two developed the haemolytic uraemic syndrome, one of whom developed severe neurological impairment. E.coli O157 phage type 21 that produced Vero cytotoxin 2 were isolated from the three children and from a goat paddock and two cows at the farm. The isolates were indistinguishable by molecular typing. The farm closed voluntarily for six weeks while recommendations to reduce the exposure of visitors to faecal contamination and to improve hygiene procedures (especially handwashing) were implemented. More research is needed into all aspects of VTEC O157 on farms, including the natural history of carriage in animals, the organism prevalence and factors that affect infectivity to humans. Further consideration is needed about the role of open farms in zoonoses, and how open farms can be assisted in reducing risks for visitors. The public need to be educated about the risks and about their responsibilities, which include the need to wash hands thoroughly and to avoid hand to mouth contact when visiting farms.

Fatal multiple drug intoxication following acute sertraline use

A 53-year-old Caucasian male victim of suicide was suspected of overdose with sertraline and alprazolam after death-scene investigation. The concentration of sertraline, a selective serotonin reuptake inhibitor, was determined by a gas chromatograph with mass selective detection. The concentration of alprazolam, a triazolobenzodiazepine, was determined by high-performance liquid chromatography. The sertraline concentration was reported at 1.0 mg/L in peripheral blood, which is greater than previously reported in other postmortem cases in which death was attributed to a multiple drug overdose. The N-desmethylsertraline concentration was reported at 0.2 mg/L in peripheral blood, which is far less than in other postmortem cases and suggests acute intoxication in this case. The alprazolam concentration was reported at 33 microg/L in heart blood, which is within the therapeutic range. The cause of death was multiple drug intoxication following acute use of sertraline, the manner of death was suicide, and the mechanism of death is an unexplained drug interaction and/or toxicity.

Identification of cytochrome P450 isozymes involved in metabolism of the alpha1-adrenoceptor blocker tamsulosin in human liver microsomes

1. The in vitro human liver metabolism of the alpha1-adrenoceptor blocker tamsulosin was investigated. When 14C-tamsulosin was incubated with human liver microsomes, it was converted to five known urinary metabolites and at least three unknown metabolites. Of the former group, the predominant metabolite was the O-deethylated metabolite (M-1), followed by the o-ethoxyphenoxy acetic acid (AM-1) and the m-hydroxylated metabolite (M-3). 2. There was a good linear relationship between AM-1 formation and testosterone 6beta-hydroxylase activity in microsomes from each of 10 individual donors. The rate of M-1 formation also correlated with the same activity, albeit the correlation curve did not pass through the origin. By contrast, the rates of M-3 and the O-demethylated metabolite (M-4) formation correlated with dextromethorphan O-demethylase activity. 3. Ketoconazole strongly inhibited AM-1 formation and reduced that of M-1 by c. 60%. Immunoinhibition studies using anti-rat antibodies supported these results. The formation of M-3 and M-4 was inhibited by quinidine and sparteine. 4. It is concluded that formation of tamsulosin metabolites, AM-1 and M-1, is catalysed by CYP3A4 whereas that of M-3 and M-4 is catalysed by CYP2D6. However, minor contributions from other CYPs cannot be excluded.

Differential exposure of surface epitopes in the beta-strand region of LOOP1 of the yeast H+-ATPase during catalysis

The plasma membrane H+-ATPase of yeast assumes distinct conformational states during its catalytic cycle. To better understand structural changes in the LOOP1 domain, a catalytically important cytoplasmic loop segment linking transmembrane segments 2 and 3, surface epitopes were examined at different stages of catalysis. A polyclonal rabbit antibody was prepared to a fusion protein consisting of LOOP1 and the maltose binding protein. This antibody was affinity-purified to produce a LOOP1-specific fraction that could be used in competition enzyme-linked immunosorbent assays to assess surface exposure of the LOOP1 epitopes. It was found that in an E1 conformation stabilized with either adenosine 5'-(beta,gamma -imino)triphosphate (AMP-PNP) or ADP, less than 10% of the LOOP1 epitopes were accessible on native enzyme. However, when the enzyme was stabilized in an E2-state with ATP plus vanadate, approximately 40% of the surface epitopes on LOOP1 became accessible to antibody. The remaining 60% of the LOOP1 epitopes were fully occluded in the native enzyme and never showed surface exposure. Enzyme-linked immunosorbent assays utilizing fusion proteins consisting of LOOP1 subdomains demonstrated that all of the available epitopes were contained in the beta-strand region (Glu-195-- Val-267) of LOOP1. The epitopes that were differentially exposed during catalysis were included in regions upstream and downstream of the highly conserved TGES sequence. Our results suggest that during catalysis either the beta-strand region of LOOP1 or an interacting domain undergoes substantial structural rearrangement that facilitates epitope exposure.

The role of interval underestimation in hyperactive children's failure to suppress responses over time

The relationship between response inhibition and time estimation abilities was investigated in a group of hyperactive and non-hyperactive children. Children performed a discrete trials intertemporal response task under two conditions. Under both conditions children had to respond within a 2 s window, which was delayed for a set period (either 5 or 15 s). In condition one (signalled condition), these response requirements were signalled by changes in the expression of a face drawn on a computer screen. In condition two (unsignalled condition), always presented on the trial following the signalled condition, these changes in expression were obscured by a hand drawn over the mouth of the face so that effective performance depended on the childs ability to estimate the point at which the facial expression changed on the preceding trial. Both groups of children had little difficulty inhibiting responses when the response requirements were signalled. All children made far more errors under the unsignalled condition. Hyperactive children displayed a systematic tendency to respond before the response window occurred. Taken together, these data give no support to the idea that hyperactivity is essentially a problem of disinhibition and raise interesting questions about the role of time mis-estimation in the disorder.

Genetic patterning of the posterior neuropore region of curly tail mouse embryos: deficiency of Wnt5a expression

The mouse mutant curly tail (ct) develops tail flexion defects and spina bifida as the result of delayed or failed closure of the posterior neuropore (PNP). With the aim of identifying genes involved in the chain of events resulting in defective neurulation, which can be detected at day 10.5 of development, we examined the expression patterns of a number of genes implicated in patterning of axial structures, mesoderm and neuroepithelium. The genes analyzed were Shh, HNF3alpha, HNF3beta, Brachyury, Hoxb1, Evx1, Fgf8, Wnt5a and Wnt5b. No differences could be detected between non-mutant embryos and ct/ct embryos with normal PNP size for any of these genes. Comparisons between ct/ct embryos with enlarged PNP and phenotypically normal ct/ct or nonmutant embryos showed differences only for Wnt5a. Expression of this gene was greatly reduced in the ventral caudal mesoderm and hindgut endoderm. Analysis of younger embryos revealed that prior to the stage at which embryos at risk of developing neural tube defects can be detected, the same proportion of ct/ct embryos shows reduced Wnt5a expression. The proportion of embryos showing reduced expression and almost undetectable expression of Wnt5a reflects the proportions of tail defects and spina bifida seen at later stages. We suggest that deficiency of Wnt5a signaling in the ventral caudal region tissues is an important component of the mechanism of development of the defects in affected curly tail mutant mice, and that it is causally related to decreased cell proliferation within the ventral caudal region. A possible relationship between decreased Wnt5a expression and reduced levels of heparan sulphate proteoglycan is discussed.

Latent structure of EEG sleep variables in depressed and control subjects: descriptions and clinical correlates

In this study, we aimed to determine the latent structure of multiple EEG sleep variables in patients with major depressive disorder (MDD) and in healthy control subjects and to examine associations between sleep factors and clinical variables. Subjects included 109 women with MDD and 54 healthy control women. EEG sleep data were collected prior to any treatment. Principal components analysis (PCA) was conducted on a set of 24 sleep variables. Separate PCAs were run for patients with MDD, control subjects, and a matched group of patients and controls. Other analyses included correlations, t-tests and MANOVA. Each PCA identified four sleep factors that explained 70% of the total variance in individual sleep variables: slow wave sleep, REM sleep, sleep continuity and REM latency/delta sleep ratio (RL/DSR). Patients with MDD and healthy controls differed on the mean value of the sleep continuity factor, and a multivariate analysis of variance based on the PCA identified MDD-control differences in REM sleep and sleep continuity. In the MDD group, slow wave sleep correlated inversely with age and personality disorder symptoms; sleep continuity correlated with subjective sleep quality and anxiety; and RL/DSR correlated inversely with age. The mean value of the REM factor was higher among treatment non-responders than responders. EEG sleep variables have a similar latent structure in women with MDD and in healthy controls. These sleep factors are supported conceptually and empirically, and correlate with clinical measures in women with MDD. Multivariate statistical techniques decrease the risk of Type I and Type II errors when using a large number of collinear sleep measures, and can clarify conceptual issues related to sleep and depression.

Palliative terminal cancer care in community hospitals and a hospice: a comparative study

BACKGROUND

Despite palliative care being an accepted role of community hospitals, there is little quantitative evidence of the type of care provided.

AIM

To obtain quantitative data comparing palliative cancer care provided in 12 community hospitals in 10 towns (approximately 350 medical beds) and in a consultant-led purpose-built hospice (12 beds).

METHOD

Retrospective medical and nursing case note analysis over one year of cancer deaths in the former Exeter Health District.

RESULTS

A total of 171 community hospital and 116 hospice casenotes were analysed. Hospice patients had significantly different reasons for admission compared with community hospital patients (P < 0.001), with pain and symptom control being more frequent and terminal nursing care less frequent reasons for admission to the hospice. Community hospital length of stay was significantly longer than hospice length of stay (P = 0.002; mean community hospital stay 16 days, mean hospice stay eight days). Symptoms on admission differed significantly. Drug prescribing on admission and at death and indications of active treatment of symptoms were broadly similar. Community hospital patients received more investigations than hospice patients, linked to the observation that around one in ten community hospital patients were admitted for investigation and active treatment. Community hospital medical notes were significantly less likely to meet minimum quality standards than were hospice notes (81/171 vs. 18/116; P < 0.001), with major deficiencies in the areas of examination, progress reporting, and absence of confirmation of death.

CONCLUSIONS

This study confirms the role of community hospitals in palliative terminal cancer care. Differences in care between community hospitals and a hospice have been demonstrated that may reflect either different admission populations to each setting or differences in the way care was delivered.

Dying from cancer in community hospitals or a hospice: closest lay carers' perceptions

BACKGROUND

Despite there being around 400 community hospitals in the United Kingdom, there is little published research on the quality of service provided by these hospitals.

AIM

To compare the quality of terminal cancer care in community hospitals with a hospice as assessed by patients' closest lay carer (relative or friend).

METHOD

Structured interview (or questionnaire based on the interview proforma) with closest lay carers of all patients dying over one year in 12 community hospitals in east Devon and a purpose-built hospice in the city of Exeter.

RESULTS

A total of 292 cases (176 in community hospitals and 116 in a hospice) were identified, resulting in 238 carers being eligible for interview or questionnaire survey. Overall, 106 successful interviews and 55 questionnaires were completed, giving a response rate of 67.6%. Carers gave a near unanimous vote of excellence for the total care given by the hospice, while around 40% of carers of patients in community hospitals considered that improvements were possible. Community hospitals attracted more negative comments than hospices, with criticism being directed at problems of communication, lack of nursing staff, and lack of support in bereavement. Carers of hospice patients were significantly more likely to be present at the time of death than those of community hospital patients [45/70 (64%) vs. 31/89 (35%); chi 2 = 13.6, P < 0.001], an observation possibly because nursing staff in community hospitals are less experienced at dealing with terminally ill patients and such hospitals have fewer adequate facilities.

CONCLUSIONS

Lay carers indicated great satisfaction with care given in the hospice and less satisfaction with care given in the community hospitals. However, the community hospitals are non-specialist units with far lower levels of trained staff. Improvements in terms of the communication skills of doctors and nurses, specific training for nurses in palliative care, and structured bereavement care could be made without necessarily increasing staffing numbers.

Retinoid signaling distinguishes a subpopulation of olfactory receptor neurons in the developing and adult mouse

We asked whether retinoic acid (RA) influences olfactory receptor neurons (ORNs) in the developing and mature mouse olfactory epithelium (oe). The distribution of retinoid receptors and binding proteins in the oe changes between embryonic days 11.5 and 13.5, the period when ORNs first differentiate and send axons into the nascent olfactory nerve. Coincident with this change, RA, which is produced in the frontonasal mesenchyme at these ages, begins to activate gene expression in a bilaterally symmetric subset of ORNs in the dorsolateral oe, as judged by the expression of an RA-responsive transgene. Axons from these RA-activated ORNs are segregated in the olfactory nerve as it extends through the frontonasal mesenchyme toward the forebrain. In vitro, RA potentiates ORN neurite growth on laminin, which, in the embryo, is found in a stripe of frontonasal mesenchyme directly associated with the olfactory nerve. RA does not modify growth on fibronectin, type IV collagen, or L1, which olfactory axons encounter in different regions of the territory between the olfactory epithelium and the brain. The pattern of RA-mediated transcriptional activation and axon segregation persists in early postnatal mice, and RA signaling can be recognized in a subset of adult ORNs in the dorsolateral oe. Thus, RA-mediated gene expression distinguishes a subpopulation of ORNs in a distinct region of the oe during the early development of the olfactory pathway, and may influence differentiation and axonal projections of ORNs in this region throughout life.

Low serum antimycobacterial drug levels in non-HIV-infected tuberculosis patients

BACKGROUND

Despite the use of directly observed therapy (DOT) by tuberculosis control programs, patient treatment failure, relapse, and acquired drug resistance remain problematic in a small number. We investigated serum drug levels in non-HIV-infected tuberculosis patients who were receiving DOT by the health department and did not respond to treatment as expected.

METHODS

The indications for checking levels were as follows: (1) slow clinical response or failure to convert the sputum culture within 12 weeks; (2) treatment failure, early disease relapse < 13 months since being declared cured; (3) relapse, late disease reactivation > or = 13 months since being declared cured; and (4) acquired drug resistance while receiving DOT. Baseline characteristics of control subjects who responded to therapy as expected were compared. Venous blood for analysis was obtained at 2 h after directly observed ingestion and measured by high-performance liquid chromatography.

RESULTS

Twenty-four patients receiving daily or twice-weekly standard therapy with isoniazid (INH, 300 or 900 mg) and rifampin (RMP, 600 mg) were identified; 22 had drug levels evaluated at 2 h. For INH, 15 of 22 patients (68%) had levels less than the reported target range. For RMP, 14 of 22 patients (64%) had low levels. Among the 14 patients receiving INH, 900 mg, and RMP, 600 mg, 4 (29%) had very low levels of both. Use of a combination INH/RMP tablet was associated with lower INH levels (p=0.04); however, RMP levels were higher (p<0.02). Alcohol use was associated with significantly higher RMP (p<0.01) serum concentrations.

CONCLUSIONS

Important questions remain concerning the utility and timing of serum drug measurements. However, if a patient is not responding to therapy as expected and one is assured that the Mycobacterium tuberculosis organism is susceptible to the drugs given and that the patient is taking the medication as prescribed, drug level monitoring should be considered.

A new family of cytokinin receptors from Cereales

The highly specific recognition of a natural cytokinin, trans-zeatin, by cytokinin-binding protein (CBP) of 67 kDa from barley leaves was detected with an assay developed on the basis of cytokinin competition in ELISA with anti-idiotype antibodies (raised against antibodies to zeatin) for complex formation with CBP. Monoclonal antibodies (mAbs) raised against 70 kDa CBP from etiolated maize seedlings cross-reacted with barley 67 kDa CBP and prevented barley CBP and trans-zeatin induced activation of transcription elongation directed by RNA polymerase I associated with barley chromatin. One mAb (Z-6) had an agonistic effect. Maize CBP replaced barley CBP in activation of RNA synthesis with cytokinin in the barley transcription system. Hence, a new family of cytokinin receptors with common functions and immunodeterminants including maize and barley CBPs was found.