Activations related to "mirror" and "canonical" neurones in the human brain: an fMRI study

In the macaque monkey ventral premotor cortex (F5), "canonical neurones" are active when the monkey observes an object and when the monkey grasps that object. In the same area, "mirror neurones" fire both when the monkey observes another monkey grasping an object and when the monkey grasps that object. We used event-related fMRI to investigate where in the human brain activation can be found that reflects both canonical and mirror neuronal activity. There was activation in the intraparietal and ventral limbs of the precentral sulcus when subjects observed objects and when they executed movements in response to the objects (canonical neurones). There was activation in the dorsal premotor cortex, the intraparietal cortex, the parietal operculum (SII), and the superior temporal sulcus when subjects observed gestures (mirror neurones). Finally, activations in the ventral premotor cortex and inferior frontal gyrus (area 44) were found when subjects imitated gestures and executed movements in response to objects. We suggest that in the human brain, the ventral limb of the precentral sulcus may form part of the area designated F5 in the macaque monkey. It is possible that area 44 forms an anterior part of F5, though anatomical studies suggest that it may be a transitional area between the premotor and prefrontal cortices.

Specific patterns of responsiveness to microbial antigens staphylococcal enterotoxin B and purified protein derivative by cord blood mononuclear cells are predictive of risk for development of atopic dermatitis

BACKGROUND

Mononuclear cells from children with active atopic dermatitis (AD) have been reported to be hyper-responsive to certain microbial stimuli, in particular staphylococcal enterotoxin B (SEB). However, it is not known whether this responsiveness is acquired during disease development, or is inherent. We investigated this question in a cohort of children at high risk of atopy followed prospectively from birth to age 3 years. We asked whether their cord blood mononuclear cell (CBMC) cytokine responses to SEB, to an unrelated microbial stimulus purified protein derivative (PPD), or to common allergens, were predictive of risk for subsequent AD development during infancy.

METHODS

Children at high risk of developing atopy were randomly selected from an ongoing prospective cohort. Cord blood was collected at birth. The children were seen at 6 months, 1, 2 and 3 years and examined for the development of AD. IFN-gamma, IL-5, IL-10 and IL-13 production by CBMC cultured in the presence of SEB, PPD, PHA, house dust mite (HDM) allergen, ovalbumin (OVA) and cat allergen was determined.

RESULTS

SEB-induced IL-5 production by CBMC was elevated in children who developed AD at 6 months (P = 0.01) and 2 years (P = 0.009). PPD-induced IL-5 responses were also elevated in CBMC from children who developed AD at 6 months, 2 years and 3 years (P = 0.05, P = 0.06 and P = 0.06, respectively), as were PPD-induced IL-10 responses (P = 0.05 at 1 years, P = 0.007 at 2 years, P = 0.003 at 3 years) and corresponding IFN-gamma responses (P = 0.05 at 6 months, P = 0.003 at 2 years, P = 0.0004 at 3 years). Increased IL-10 responses to HDM allergen were also observed throughout the observation period in CBMC from children who developed AD.

CONCLUSION

Children who develop infantile AD appear to have a predisposition to respond to SEB in a Th2-dominant manner involving selective stimulation of IL-5 production. The increased IL-10 and IFN-gamma induced in response to PPD by children with AD may point to additional intrinsic differences in responses to microbial stimuli between those at high vs. those at low risk for AD, which merit more detailed investigations.

In vitro migration of cytotrophoblasts through a decidual endothelial cell monolayer: the role of matrix metalloproteinases

Deficient trophoblast invasion is a major feature of pre-eclampsia. In vitro studies suggest that in normal pregnancy, maternal cells may play a role in controlling trophoblast invasion, although the exact nature of the regulatory interactions between these cells is not fully understood. To examine the effect of maternal-placental cell interactions on matrix metalloproteinase (MMP) secretion and endovascular cytotrophoblast migration in normal pregnancy and in pre-eclampsia, we performed co-culture experiments using cytotrophoblasts from normal pregnancies, together with decidual endothelial cells from both normal and preeclamptic pregnancies. Cells were incubated on semi-permeable membranes with or without phorbol 12-myristate 13-acetate (PMA). Results showed that third trimester cytotrophoblasts are migratory under basal conditions and display a different MMP profile from decidual endothelial cells. Co-culture did not damage either cell type and resulted in reduced latent MMP-9 secretion and reduced cytotrophoblast migration. Although PMA upregulated MMPs in decidual endothelial cells, it had no effect on cytotrophoblast MMP secretion. PMA, however, reduced cytotrophoblast migration. Pre-eclamptic decidual endothelial cells showed reduced MMP-1 secretion, but overall were not different in co-culture from normal endothelial cells. This study demonstrates the effectiveness of a bilayer co-culture model to study maternal-foetal cell interactions and provides evidence that maternal cells may contribute to the control of endovascular cytotrophoblast invasion.

Presence of caprine arthritis-encephalitis virus (CAEV) proviral DNA in genital tract tissues of superovulated dairy goat does

Transmission of caprine arthritis-encephalitis virus (CAEV) is not completely understood and the vertical route of infection from the goat to the embryo or to the fetus needs to be investigated. This route of infection involves the presence of CAEV in the genital tract tissues. Prior studies have detected CAEV-infected cells in genital secretions and in flushing media recovered during embryo collection from infected goats. To specify the origin of these cells, we conducted a double-nested polymerase chain reaction (PCR) test on embryo flushing media and on mammary gland, mammary lymph node, synovial membrane, pelvic lymph node, uterus and oviduct tissues from 25 CAEV-infected (blood PCR positive) embryo donor goats for the presence of CAEV proviral DNA. The presence of proviral DNA was found in 22 of 25 mammary gland samples, 14 of 25 uterus samples, and in 16 of 25 oviduct samples. Nineteen of 25 goats had at least one positive genital tract sample. Flushing media from 11 goats were PCR positive. All goats with positive-flushing media were oviduct positive. Of this group of does, except for 1 of the 11, infection of flushing media correlated with infection of almost all the other tissues examined. The frequency of positive tissues for flushing media-positive goats (61/66; 92%) was significantly higher than that for flushing media-negative goats (50/84; 60%) (P<0.01). This study demonstrated the presence of CAEV-infected cells in the goat genital tract. The presence of CAEV-infected cells in the uterus and oviducts suggests potential for vertical transmission of CAEV from doe to embryo or fetus.

Phylogenetic relationships of dengue-1 viruses from Argentina and Paraguay

We sequenced the Capsid-pre Membrane (C/prM) and the Envelope-Nonstructural protein 1 (E/NS1) regions of 24 recent isolates of dengue-1 (DEN-1) from South America. This included 12 Argentinean and 11 Paraguayan DEN-1 strains isolated in 2000 plus a Paraguayan strain isolated in 1988. These sequences were compared with published sequences of DEN-1 isolated worldwide to determine the origin of these isolates. Pairwise comparisons of strains from Paraguay and Argentina revealed a nucleotide divergence of 0-5% in the E/NS1 region and 0-3% in the C/prM region. Our results showed that these viruses belong to the same genotype, but can be separated into two clades. Interestingly, both clades circulated simultaneously in the same geographic area during the 2000 outbreaks. Amino acid differences were found between both clades in the C/prM region at position 100 (Lys vs. Arg) and in the E/NS1 region at positions 722 (Ala vs. Thr). Although the geographic movement of DEN-1 virus can not be unequivocally traced from the genetic relationship determined here, our results suggest that the recent epidemics in Argentina and Paraguay were due to the re-emergence of a previously circulating strain, or to the virus circulating unnoticed, rather than to the introduction of a new genotype.

Modulation of prostacyclin and thromboxane secretion by cytotrophoblasts from normal and pre-eclamptic human pregnancies

We and others have previously observed an imbalance in cytotrophoblast secretion of the vasoactive prostanoids prostacyclin and thromboxane A(2) in pre-eclampsia. To examine the effects of potential modulators of this imbalance, cytotrophoblasts isolated from normal and pre-eclamptic pregnancies were incubated in the presence of lipopolysaccharide, the calcium ionophore A23187, tumour necrosis factor alpha, or interleukin 1beta, with or without the cyclo-oxygenase inhibitor, indomethacin. Further incubations included the drugs tranylcypromine, a prostacyclin synthetase inhibitor (0.1, 10 microM ), or the thromboxane synthetase inhibitor, pirmagrel (0.001, 1 microM ). Results showed that cytotrophoblasts from pre-eclamptic pregnancies had increased thromboxane production and significant stimulation of prostacyclin production by lipopolysaccharide and calcium ionophore. Lipopolysaccharide stimulated thromboxane production in normal cytotrophoblasts, while indomethacin almost completely inhibited production of both prostanoids. Tranylcypromine mildly inhibited prostacyclin production in normal cytotrophoblasts only, whereas pirmagrel strongly inhibited thromboxane production in a dose-related manner, with reciprocal increase in prostacyclin production occurring in cytotrophoblasts from pre-eclamptic pregnancies. This study confirmed that cytotrophoblasts from pre-eclamptic women had increased thromboxane production and showed that pirmagrel, at the relatively low dose of 0.001 microM, was able to normalize the imbalance of thromboxane and prostacylin production and may therefore warrant further investigation as a treatment for pre-eclampsia.

Localisation of the subthalamic nucleus using Radionics Image Fusion and Stereoplan combined with field potential recording. A technical note

Subthalamic nucleus stimulation is an effective therapy for alleviating parkinsonian tremor, rigidity and bradykinesia. Although microelectrode recording is said to be essential for accurate targeting, this often prolongs the operation and the multiple recording tracts required may increase the incidence of complications, particularly haemorrhage. We describe a technique for implantation of deep brain electrodes in the subthalamic nucleus using MRI/CT fusion for anatomical localisation followed by bipolar recording of focal field potentials via the implanted stimulating electrode for neurophysiological confirmation of the stimulation site. The technique is effective, safe and requires much less time, and can be used as an alternative method to microelectrode recording.

Striatal contribution to cognition: working memory and executive function in Parkinson's disease before and after unilateral posteroventral pallidotomy

The basal ganglia are intimately connected to the frontal cortex via five fronto-striatal circuits. While the role of the frontal cortex in cognition has been extensively studied, the contribution of the basal ganglia to cognition has remained less clear. In Parkinson's disease, posteroventral pallidotomy (PVP) involves surgical lesioning of the internal section of the globus pallidus (GPi, the final output pathway from the basal ganglia) to relieve the motor symptoms of the disorder. PVP in Parkinson's disease provides a unique opportunity to investigate the impact of disruption of striatal outflow to the frontal cortex on cognition. We assessed executive function and working memory after withdrawal of medication in 13 patients with Parkinson's disease before and 3 months after unilateral PVP compared to 12 age- and IQ-matched normals assessed twice with an interval of 3 months. The tests used were: Wisconsin Card Sorting (WCST), Self-Ordered Random Number Sequences, Missing Digit Test, Paced Visual Serial Addition Test (PVSAT), and Visual Conditional Associative Learning Test (VCALT). After PVP, the patients performed significantly better on the Self-Ordered Random Number Sequences and the WCST, an improvement that was also observed in the normals across the two assessment and is therefore likely to reflect practice effects. Relative to the normals, the patients showed significant differential change following PVP on the Missing Digit Test and PVSAT, on which they performed worse after compared to before surgery, while the controls performed better on the second assessment. For the patients, performance on the VCALT also indicated deterioration after PVP, but the changes approached significance. The side of PVP had no effect on the results. The pattern of change observed 3 months after PVP was maintained at 15-month follow-up. The results suggest that striatal outflow to the frontal cortex may be essential for those aspects of executive function that showed deterioration after PVP.

Presence of caprine arthritis-encephalitis virus (CAEV) infected cells in flushing media following oviductal-stage embryo collection

To improve the knowledge on the risk of transmission of the caprine arthritis-encephalitis virus (CAEV) during embryo manipulations, we conducted a double-nested polymerase chain reaction (PCR) for CAEV proviral-DNA on flushing media recovered from the oviducts 48 h after the beginning of estrus and on blood from 89 donor does. Sixty-four does had negative blood and flushing media by PCR. Among the 25 CAEV infected goats (blood PCR positive), 11 were PCR flushing media positive (P < 0.01). Cell lysate from flushing media samples that were PCR positive were serially diluted 10 times at 1:100. Starting with the second 1:100 dilution all the cell lysate samples were PCR negative. The mean number of embryos recovered was not significantly different between goats with flushing media PCR positive and goats with flushing media PCR negative (6.0 +/- 5.4 versus 7.8 +/- 4.4, respectively; mean +/- S.D.) nor between goats with blood PCR positive and goats with blood PCR negative (7.0 +/- 5.0 versus 5.9 +/- 5.3; mean +/- S.D.). The presence of CAEV infected cells in oviductal flushing media from infected donor does was indicated for the first time during this study. The absence of flushing media PCR positive for goat blood PCR negative seemed to allow the use of the blood PCR test to confidently predict the absence of CAEV provirus in the oviductal fluid.

Controlling deamidation rates in a model peptide: effects of temperature, peptide concentration, and additives

The rate of deamidation of the Asn residue in Val-Tyr-Pro-Asn-Gly-Ala (VYPNGA), a model peptide, was determined at pH 9 (400 mM Tris buffer) as a function of temperature and peptide concentration. Over the temperature range 5-65 degrees C, deamidation followed Arrhenius behavior, with an apparent activation energy of 13.3 kcal/mol. Furthermore, increasing the peptide concentration slows the rate of deamidation. Self-stabilization with respect to deamidation has not been reported previously. The rate of deamidation was also determined in the presence of sucrose and poloxamer 407 (Pluronic F127). In both cases, the rate of deamidation was retarded by up to 40% at 35 degrees C. In aqueous solutions containing poloxamer 407, the degree of stabilization is independent of formation of a reversible thermosetting gel. With sucrose, maximum reduction in the deamidation rate was attained with as little as 5% (w/v). Addition of sucrose results in a greater conformational preference for a type II beta-turn structure, which presumably is less prone to intramolecular cyclization and subsequent deamidation.

Cross-reactivity and clinical impact of the antibody response to hepatitis C virus second envelope glycoprotein (E2)

The genotype of hepatitis C virus (HCV) can profoundly affect the success of antiviral therapy for HCV infection. A possible contributing factor is a varied immune response elicited by infection with different HCV genotypes. In this study, full-length E2 proteins of HCV genotypes 1a, 1b, 2a, and 2b were used to determine the fraction of the humoral immune response to HCV E2 that is genotype specific. Greater than 90% of all infected individuals had serum antibodies to the four E2 proteins. Overall, individuals infected with genotype 1a or 1b were characterized by variable immune responses to HCV E2 with relatively high amounts of cross-reactivity with other E2 proteins. Individuals infected with genotype 2a or 2b exhibited a strong preferential reactivity to genotype 2a and 2b E2 proteins. Individuals with elevated titers to HCV E2 were more likely to be infected with genotype 2a and had a significantly lower median viral load. These findings indicate that the antibody response to HCV E2 is affected by the genotype of the virus and that induction of a strong humoral immune response to HCV E2 may contribute to a decreased viral load.

Community nurses' contribution to oral health

Oral health is an important component of general health and well-being. Although oral health has improved dramatically in children and young adults, oral diseases remain common, particularly among disadvantaged and vulnerable groups. Many patients seen by community nurses will fall into these categories and are less likely to have sought treatment. This article presents the epidemiology of oral diseases and conditions for specific groups in society that community nurses will be caring for. It looks at prescribing principles and describes treatment and advice for common oral conditions, including those where prescription may be appropriate. Community nurses play an important role in the oral health care of society, particularly among those least likely to access dental services.

Impairment of movement initiation and execution but not preparation in idiopathic dystonia

Imaging studies have reported impaired activation of the striatum and their frontal projection sites in dsytonia, areas which are considered to play a role in motor preparation, movement initiation and execution. The aim of this study was to investigate the processes of motor preparation, response initiation and execution in patients with idiopathic torsion dystonia (ITD). We assessed 12 patients with ITD and 12 age-matched controls on a number of reaction time (RT) tasks that differed in degree of motor preparation possible. Subjects performed a visual simple RT (SRT) task, an uncued four-choice reaction time (CRT) task and a fully precued four-choice RT task. A stimulus 1-stimulus 2 (S1-S2) paradigm was used. The warning signal/precue (S1) preceded the imperative stimulus (S2) by either 0 ms (no warning signal or precue) 200 ms, 800 ms, 1,600 ms or 3,200 ms. The patients with ITD had significantly slower RTs and movement times than normals across all RT tasks. The unwarned SRT trials were significantly faster than the uncued CRT trials for both groups. For both groups, precued CRTs were significantly faster than the uncued CRTs. The results show that while response initiation and execution are significantly slower in patients with ITD than normals, movement preparation is not quantitatively or qualitatively different. The results are discussed in relation to previous imaging, behavioural and electrophysiological studies and models of fronto-striatal dysfunction in ITD.

Phylogenetic relationships within the cyst-forming nematodes (Nematoda, Heteroderidae) based on analysis of sequences from the ITS regions of ribosomal DNA

The ITS1, ITS2, and 5.8S gene sequences of nuclear ribosomal DNA from 40 taxa of the family Heteroderidae (including the genera Afenestrata, Cactodera, Heterodera, Globodera, Punctodera, Meloidodera, Cryphodera, and Thecavermiculatus) were sequenced and analyzed. The ITS regions displayed high levels of sequence divergence within Heteroderinae and compared to outgroup taxa. Unlike recent findings in root knot nematodes, ITS sequence polymorphism does not appear to complicate phylogenetic analysis of cyst nematodes. Phylogenetic analyses with maximum-parsimony, minimum-evolution, and maximum-likelihood methods were performed with a range of computer alignments, including elision and culled alignments. All multiple alignments and phylogenetic methods yielded similar basic structure for phylogenetic relationships of Heteroderidae. The cyst-forming nematodes are represented by six main clades corresponding to morphological characters and host specialization, with certain clades assuming different positions depending on alignment procedure and/or method of phylogenetic inference. Hypotheses of monophyly of Punctoderinae and Heteroderinae are, respectively, strongly and moderately supported by the ITS data across most alignments. Close relationships were revealed between the Avenae and the Sacchari groups and between the Humuli group and the species H. salixophila within Heteroderinae. The Goettingiana group occupies a basal position within this subfamily. The validity of the genera Afenestrata and Bidera was tested and is discussed based on molecular data. We conclude that ITS sequence data are appropriate for studies of relationships within the different species groups and less so for recovery of more ancient speciations within Heteroderidae.

Syntaxin 1A is delivered to the apical and basolateral domains of epithelial cells: the role of munc-18 proteins

SNARE (Soluble N-ethyl-maleimide sensitive factor Attachment protein Receptor) proteins assemble in tight core complexes, which promote fusion of carrier vesicles with target compartments. Members of this class of proteins are expressed in all eukaryotic cells and are distributed in distinct subcellular compartments. The molecular mechanisms underlying sorting of SNAREs to their physiological sites of action are still poorly understood. Here have we analyzed the transport of syntaxin1A in epithelial cells. In line with previous data we found that syntaxin1A is not transported to the plasma membrane, but rather is retained intracellularly when overexpressed in MDCK and Caco-2 cells. Its delivery to the cell surface is recovered after munc-18-1 cotransfection. Furthermore, overexpression of the ubiquitous isoform of munc-18, munc-18-2, is also capable of rescuing the transport of the t-SNARE. The interaction between syntaxin 1A and munc-18 occurs in the biosynthetic pathway and is required to promote the exit of the t-SNARE from the Golgi complex. This enabled us to investigate the targeting of syntaxin1A in polarized cells. Confocal analysis of polarized monolayers demonstrates that syntaxin1A is delivered to both the apical and basolateral domains independently of the munc-18 proteins used in the cotranfection experiments. In search of the mechanisms underlying syntaxin 1A sorting to the cell surface, we found that a portion of the protein is included in non-ionic detergent insoluble complexes. Our results indicate that the munc-18 proteins represent limiting but essential factors in the transport of syntaxin1A from the Golgi complex to the epithelial cell surface. They also suggest the presence of codominant apical and basolateral sorting signals in the syntaxin1A sequence.

Analysis of trk A and p53 association

trk A tyrosine kinase (the high affinity receptor for nerve growth factor) binds to the p53 tumour suppressor protein in vitro and in vivo. Our aim was to determine which regions of p53 are involved in trk A association. In vitro binding experiments using baculovirus expressed trk A and in vitro transcribed and translated C-terminus p53 deletion mutants show amino acids 327-338 critical for association. Also, analysis with mutants at the N-terminus, conserved regions II, III, IV and V or amino acid positions 173, 175, 181, 248 and 249 (which are amino acids frequently mutated in a variety of neoplasms and transformed cell lines), show that these sites are not involved in trk A binding. Importantly, similar results are obtained after immunoprecipitation of lysates from p53 negative fibroblasts expressing trk A and the above p53 mutant proteins. These data suggest that the amino-terminus of the oligomerisation domain of p53 is involved in p53/trk A association.

Heterogeneity in diphtheria-tetanus-acellular pertussis vaccine-specific cellular immunity during infancy: relationship to variations in the kinetics of postnatal maturation of systemic th1 function

Cellular immunity to vaccines is highly variable during infancy. This study addressed the hypothesis that these responses are governed by the pace of maturational changes in adaptive immune competence, in particular, cellular functions that underlie the postnatal transition from Th2 to Th1 "bias." Tetanus-specific cytokine responses were tracked in peripheral blood mononuclear cells collected from infants at months 2, 4, 6, 12, and 18. These were compared with polyclonal responses. Results show that the Th2 component of the vaccine response develops rapidly and remains stable, unlike interferon (IFN)-gamma production, which also is initiated early but commonly declines after the final priming dose at 6 months. However, between 12 and 18 months, the IFN-gamma component of the vaccine-specific response has a spontaneous resurgence that coincides with a parallel increase in overall IFN-gamma production capacity. The Th2 component of vaccine-specific responses was more prominent in children with atopic family history.

Prevalence of breastfeeding at four months in general practices in south London

BACKGROUND

Successive quinquennial National Infant Feeding Surveys have provided a valuable picture of national and regional variations in infant feeding practices within the United Kingdom. Social variation in breastfeeding has been recognised to be an important source of health inequalities in childhood by the Independent Inquiry into Inequalities in Health Report.

AIM

To determine the prevalence of breastfeeding at birth and at four months in a sample of women from urban general practices, its variation between practices, and relation to practice population deprivation scores. To report the timing of introduction of solid feeds.

DESIGN OF STUDY

Cross-sectional questionnaire survey based on a random cluster sample.

SETTING

Women with infants aged four months in general practices in South London.

METHOD

Mode of infant feeding at birth and four months, and time of introduction of solids. Jarman score as a measure of practice population deprivation. Housing tenure, maternal ethnic group, and maternal age at leaving full-time education.

RESULTS

Twenty-five general practices were sampled. Median practice Jarman score was 15.0 (interquartile range [IQR] = 12.6-21.9). Responses were received from 1053 out of 1532 mothers approached (69%). Of these, 87% (897) had breastfed at birth, while 59% (609) were still breastfeeding their babies at four months. Mothers in rented accommodation were less likely to breastfeed than owner-occupiers (odds ratio [95% CI] = 0.52 [0.37-0.74]), as were women of white, compared with those of black, ethnic origin (odds ratio [95% CI] = 0.55 [0.36-0.82]). Those who completed up to two years and more than two years education after the age of 16 were 2.94 (95% CI = 1.85-4.66) and 9.25 (95% CI = 6.02-14.21) more likely to breastfeed at four months, respectively, than mothers whose formal education was completed at or before 16 years. Practice-specific rates of breastfeeding ranged from 71% to 100% at birth (median 87%; IQR = 79-93%) and 22% to 83% at four months (median 61%; interquartile range = 47-66%). The intra-practice correlation coefficient for breastfeeding at four months was 0.052 (within-cluster variance = 0.23, between-cluster variance = 0.013). There was no association between breastfeeding at four months and practice-specific Jarman score. Median age of starting solids was 16 weeks (IQR = 15-17 weeks).

CONCLUSIONS

Housing tenure, maternal education, and ethnic group are significantly associated with breastfeeding prevalence at four months. Between-practice variation in breastfeeding prevalence is not associated with measures of practice population deprivation, as assessed by Jarman scores. Consideration should be given to including information on maternal ethnic group and housing tenure in future National Infant Feeding Surveys. Current weaning practices fall short of the recommendation of the World Health Assembly.

Frequency analysis of involuntary movements during wrist tracking: a way to identify ms patients with tremor who benefit from thalamotomy

To identify those multiple sclerosis (MS) patients with disabling tremor who will benefit most from thalamotomy, measurements of frequency spectra of involuntary movements during visually guided wrist tracking were carried out in 11 consecutive patients with MS before and after ventrolateral thalamotomy. Thalamotomy was significantly more effective if patients had disruptive action tremor which appeared as a single peak in the frequency spectra. Such patients showed an average reduction of nearly 80% in tremor magnitude after thalamotomy. In comparison, surgery produced an average reduction of only 30% in 3 other patients who had action tremor but showed multiple peaks in the frequency spectra. Frequency analysis of involuntary movements identifies those MS patients with disabling tremor who benefited most from thalamotomy.

Stabilization of p53 by p14ARF without relocation of MDM2 to the nucleolus

The alternative product of the human INK4a/ARF locus, p14ARF, has the potential to act as a tumour suppressor by binding to and inhibiting the p53 antagonist MDM2. Current models propose that ARF function depends on its ability to sequester MDM2 in the nucleolus. Here we describe situations in which stabilization of MDM2 and p53 occur without relocalization of endogenous MDM2 from the nucleoplasm. Conversely, forms of ARF that do not accumulate in the nucleolus retain the capacity to stabilize MDM2 and p53. We therefore propose that nucleolar localization is not essential for ARF function but may enhance the availability of ARF to inhibit MDM2.

bcl-2 and immunoglobulin gene rearrangement in patients with hepatitis C virus infection

An association between chronic hepatitis C virus (HCV) infection and clonal proliferation of B cells, including B cell lymphoma, has recently been demonstrated. However, the mechanism of malignant transformation is still unknown. It has been shown that B cells from patients with type II mixed cryoglobulinaemia (MC), strongly express the antiapoptotic bcl-2 oncogene product. Therefore, we investigated a possible mechanism of lymphomagenesis, the occurrence of bcl-2 and immunoglobulin gene rearrangement (IgH) in HCV-infected patients. Three groups of patients were studied: (1) 44 patients with HCV and MC (anti-HCV and HCV RNA positive); (2) 59 patients with chronic HCV infection without MC; (3) 50 patients with chronic liver disease (CLD) not related to HCV infection. The t(14;18) translocation (MBR bcl-2-JH) and IgH rearrangement (FR3/JH) were detected by polymerase chain reaction (PCR) in peripheral mononuclear cells. bcl-2 translocation was detected in 17/44 (39%), 7/59 (12%) and in none of the patients of groups 1, 2 and 3 respectively (P < 0.01). Monoclonal IgH rearrangement was detected in 15/44 (34%), 5/59 (8.5%) and 2/50 (4%) patients of groups 1, 2 and 3 respectively (P < 0.05). HCV-infected patients had a higher prevalence of monoclonal IgH rearrangement and bcl-2 translocation than patients with CLD of other aetiologies. These data suggest that HCV may play a role in the multistep mechanism of lymphomagenesis by inducing clonal proliferation of B cells and inhibition of apoptosis.

Plasma from preeclamptic women stimulates decidual endothelial cell growth and prostacyclin but not nitric oxide production: close correlation of prostacyclin and thromboxane production

OBJECTIVE

To examine the effect of plasma from preeclamptic women on production of the vasoactive substances prostacyclin, thromboxane, nitric oxide, and cyclic guanosine monophosphate (cGMP) by decidual endothelial cells; to determine any effects on cell growth and health; and to examine whether cells from preeclamptic women are activated compared with cells from normal women.

METHODS

Decidual endothelial cells from normal and preeclamptic women were incubated for 24 hours in media containing 10% plasma from preeclamptic women or matched normal women. Prostacyclin and thromboxane production was measured, as was nitric oxide and cGMP production after a further 45-minute generation period in 2% test plasma. Cell numbers and lactate dehydrogenase release were also determined.

RESULTS

In plasma from preeclamptic women, cells grew significantly faster (P <.05), prostacyclin production was increased (P <.05), and lactate dehydrogenase release was reduced (P <.01). Production of thromboxane, nitric oxide, and cGMP was not significantly affected. Decidual endothelial cells from preeclamptic women had increased growth (P <.0001) and produced more prostacyclin (P <.05) and nitric oxide (P <.001) than normal decidual endothelial cells. There were highly significant correlations between prostacyclin and thromboxane production for incubations in plasmas from preeclamptic women and between background levels of prostacyclin in each plasma from preeclamptic women and the prostacyclin produced in incubations containing that plasma (P <.0001).

CONCLUSION

We found that plasma from preeclamptic women contained a factor that stimulated endothelial cell growth and regulated production of related amounts of prostacyclin and thromboxane. The plasma level of this factor appeared to be related to background levels of prostacyclin. The results also indicated that decidual endothelial cells from preeclamptic women were in a relatively activated state.

Cross-sectional and prospective relationships of interleukin-6 and C-reactive protein with physical performance in elderly persons: MacArthur studies of successful aging

BACKGROUND

Chronic inflammation has been proposed as a biological mechanism underlying the decline in physical function that occurs with aging. The purpose of this investigation was to examine the cross-sectional and prospective relationships between markers of inflammation, interleukin-6 (IL-6) and C-reactive protein (CRP), with several measures of physical performance in older persons aged 70 to 79 years.

METHODS

Subjects were 880 high-functioning men and women participating in the MacArthur Study of Successful Aging (n = 1189), a subset of the Established Populations for Epidemiologic Studies of the Elderly (n = 4030). Plasma IL-6 and CRP levels were determined by enzyme-linked immunosorbent assay and log transformed to normalize the distributions. Physical function measures included handgrip strength, signature time, chair stands (time to complete five repetitions), and 6-m walk time.

RESULTS

Women had lower (p < .05) IL-6 levels than men, but there was no significant difference between blacks and whites. IL-6 and CRP levels were higher (p < .05) in current smokers than in nonsmokers and in those with a greater body mass index (BMI). Hours per year undertaking moderate and strenuous physical activity were also related to inflammatory markers with higher (p < .001) IL-6 and CRP levels in less active individuals. After adjusting for age, sex, race, BMI, smoking status, use of nonsteroidal anti-inflammatory drugs, and prevalence of morbidity, those in the top two quartiles for walking speed had lower (p = .012) IL-6 levels than those in the bottom quartile. In addition, there was a trend (p = .038) for lower CRP levels in those with higher walking speed. CRP levels were also lower (p = .04) in individuals in the top quartile for grip strength. No significant differences were noted for chair stands or signature time performance. Repeat performance measures obtained on 405 subjects (67% of those eligible at baseline) obtained 7 years later had declined significantly (grip strength, 18%; signature time, 21%; walking speed, 31%; p < .001), except for the chair rise; however, baseline IL-6 and CRP were not associated with a change in performance. However, those who died or who were unable to undergo testing had higher baseline IL-6 and CRP levels (p < .01) and slower walking speed (p < .05).

CONCLUSIONS

Although IL-6 has been shown to predict onset of disability in older persons and both IL-6 and CRP are associated with mortality risk, these markers of inflammation have only limited associations with physical performance, except for walking measures and grip strength at baseline, and do not predict change in performance 7 years later in a high-functioning subset of older adults.

Human monoclonal antibodies that inhibit binding of hepatitis C virus E2 protein to CD81 and recognize conserved conformational epitopes

The intrinsic variability of hepatitis C virus (HCV) envelope proteins E1 and E2 complicates the identification of protective antibodies. In an attempt to identify antibodies to E2 proteins from divergent HCV isolates, we produced HCV E2 recombinant proteins from individuals infected with HCV genotypes 1a, 1b, 2a, and 2b. These proteins were then used to characterize 10 human monoclonal antibodies (HMAbs) produced from peripheral B cells isolated from an individual infected with HCV genotype 1b. Nine of the antibodies recognize conformational epitopes within HCV E2. Six HMAbs identify epitopes shared among HCV genotypes 1a, 1b, 2a, and 2b. Six, including five broadly reactive HMAbs, could inhibit binding of HCV E2 of genotypes 1a, 1b, 2a, and 2b to human CD81 when E2 and the antibody were simultaneously exposed to CD81. Surprisingly, all of the antibodies that inhibited the binding of E2 to CD81 retained the ability to recognize preformed CD81-E2 complexes generated with some of the same recombinant E2 proteins. Two antibodies that did not recognize preformed complexes of HCV 1a E2 and CD81 also inhibited binding of HCV 1a virions to CD81. Thus, HCV-infected individuals can produce antibodies that recognize conserved conformational epitopes and inhibit the binding of HCV to CD81. The inhibition is mediated via antibody binding to epitopes outside of the CD81 binding site in E2, possibly by preventing conformational changes in E2 that are required for CD81 binding.

Antigen-specific responses to diphtheria-tetanus-acellular pertussis vaccine in human infants are initially Th2 polarized

Immune responses to exogenous antigens in infant experimental animals display various degrees of Th2 polarization. Preliminary evidence from small human studies suggest a similar age-dependent response pattern to vaccines, but detailed investigations on vaccine immunity during infancy have not yet been undertaken. We report below the results of a comprehensive prospective study on responses to the tetanus component of the diphtheria, tetanus, acellular pertussis (DTaP) vaccine in a cohort of 55 healthy children, employing peripheral blood mononuclear cells (PBMC) collected at the 2-, 4-, and 6-month vaccinations and at 12 months. Antigen-specific production of interleukin-4 (IL-4), IL-5, IL-6, IL-9, IL-10, IL-13, and gamma interferon (IFN-gamma) was determined at each sample point, in parallel with polyclonal (phytohemagglutinin PHA-induced) cytokine responses. Our results indicate early and persistent Th2 responses to the vaccine, in contrast to a more delayed and transient pattern of IFN-gamma production. This initial disparity between the Th1 and Th2 components of the vaccine response was mirrored by patterns of polyclonally induced cytokine production, suggesting that the delayed maturation of the Th1 component of the vaccine response during infancy is secondary to developmental processes occurring within the overall Th cell system.

Genetic diversity of the Junin virus in Argentina: geographic and temporal patterns

RNA was purified from 39 strains of cell-cultured Junin virus (JUN) from central Argentina, which included both human- and rodent-derived isolates (a total of 26 and 13, respectively), as well as from 2 laboratory JUN strains, XJ Cl3 and XJ #44. JUN-specific primers were used to amplify a 511-nucleotide (nt) fragment of the nucleocapsid protein gene and a 495-nt fragment of the glycoprotein 1 (GP1) gene. Genetic diversity among JUN strains studied was up to 13% at the nt level and up to 9% at the amino acid (aa) level for the GP1 gene and up to 9% (nt) and 4% (aa) for the NP gene. Phylogenetic analyses of both genes revealed three distinct clades. The first clade was composed of the JUN strains from the center of the endemic area and included the majority of JUN strains analyzed in the current study. The second clade contained 4 JUN strains isolated between 1963 and 1971 from Cordoba Province, the western-most edge of the known endemic area. The third clade contained 4 JUN strains that originated from Calomys musculinus trapped in Zarate, the northeastern edge of the known endemic area. Certain JUN sequences, which were obtained from GenBank and identified as XJ, XJ #44, and Candid #1 strains, appeared to form a separate clade. Over 400 nt of the GP1 and GP2 genes were additionally sequenced for 7 JUN strains derived from patients with different clinical presentations and outcomes of Argentine hemorrhagic fever. Analysis of the corresponding aa sequences did not allow us to attribute any particular genetic marker to the changing severity or clinical form of the human disease.

Development of immunologic memory against tetanus toxoid and pertactin antigens from the diphtheria-tetanus-pertussis vaccine in atopic versus nonatopic children

BACKGROUND

Recent findings suggest that a hallmark of the atopic phenotype is reduced capacity to respond to vaccine antigens, as well as to environmental allergens, during infancy. This deficiency, which is most marked for the cytokine IFN-gamma, appears transient but can result in a long-lasting imbalance within T helper cell (T(H)) memory responses to allergens. Indirect evidence suggests that parallel effects may occur within immunologic memory responses against vaccine antigens in atopic children.

OBJECTIVE

Our purpose was to compare vaccine antigen-specific T(H) memory responses in atopic and nonatopic children.

METHODS

We analyzed specific serum IgG and cytokine responses to pertactin and tetanus antigens as well as to mitogen (PHA) and house dust mite (HDM) allergen in 25 HDM-sensitized atopic and 25 nonatopic 6-year-old children who were vaccinated and boosted with diphtheria-tetanus-pertussis (DTP) vaccine.

RESULTS

PBMCs from the atopic subjects produced higher levels of T(H)1 and T(H)2 cytokines to HDM allergen and PHA. Vaccine antibody titers were normal in the atopic subjects; vaccine-specific T(H)2 responses were rarely detectable, yet T(H)1 (IFN-gamma) responses, in particular against tetanus, were frequent and higher in the atopic subjects (121.5 [SE 64.3] vs 8.0 [3.5] pg/mL culture fluid, P =.04). Corresponding pertactin responses were comparable in both groups.

CONCLUSIONS

At the completion of the full primer-booster DTP vaccination regimen, levels of vaccine-specific immunity in atopic 6-year-old children are at least equivalent to their nonatopic counterparts, indicating that the transient atopy-associated deficiency in T(H)1 function in childhood can be successfully overcome by appropriate vaccination and boosting regimens.

The involvement of physicians in VA home care: results from a national survey

OBJECTIVES

To examine the role of physicians in the Veteran Affairs (VA) home-based primary care (HBPC) program and to identify variables that predict whether physicians make home visits and volume of home visits made.

DESIGN

Descriptive and regression analyses of responses from a mail survey.

PARTICIPANTS

Forty-five physicians affiliated with VA HBPC programs. MAIN SURVEY TOPICS: Self-reported work load, attitudes toward home care, reasons for home visits, administrative policies regarding physicians' role in patient care management, and time commitment to home care.

RESULTS

A majority of physicians believed strongly in the importance of home care and made home visits for reasons consistent with their training. Physician attitude toward home care and preoccupation with office or hospital practice were related to whether or not physicians made home visits. Degree of preoccupation with office practice and amount of salary support from VA HBPC were significant predictors of the number of visits made (R2 = 0.44).

CONCLUSIONS

These findings indicate that most physicians will make home visits if they believe that home care is valuable and if their time commitment is supported financially. Managed care plans that own and operate home care programs and have the capacity to transfer primary care management to physicians who derive financial support from the programs should find this information particularly relevant.

Effects of hypoxia on regulation of prostanoid production in decidual endothelial cells in normal and preeclamptic pregnancy

OBJECTIVES

To examine the effect on prostacyclin and thromboxane production of incubating decidual endothelial cells under hypoxic conditions, comparing cells from normal and preeclamptic pregnancies. Furthermore, to determine whether hypoxia is deleterious to cell growth, and test the effects of stimulation and inhibition on prostanoid production.

METHODS

Decidual endothelial cells were exposed for a total of 40 hours to normoxic (20% O2) or hypoxic (2% O2) conditions. Prostacyclin and thromboxane secretion over the final 24 hours of incubation was measured and cell numbers after incubation determined. Lipopolysaccharide (LPS) (1.0 microgram/mL) was used as a stimulator and pirmagrel (1.0 mumol/L) and tranylcypromine (10.0 mumol/L) as prostanoid synthase inhibitors.

RESULTS

Incubations in hypoxia resulted in increased thromboxane (P < .05) but no change in prostacyclin production. This thromboxane increase was abrogated by pirmagrel. LPS caused significant stimulation of prostacyclin and thromboxane secretion and both LPS and hypoxia resulted in lower cell numbers. Decidual endothelial cells from normal and preeclamptic pregnancies were generally not different.

CONCLUSIONS

This study indicates that in preeclampsia, where decidual endothelial cells are in a relatively more hypoxic environment, thromboxane production by these cells is likely to be increased and the prostacyclin/thromboxane ratio decreased. The thromboxane synthase inhibitor, pirmagrel, was able to reverse this abnormal increased secretion of thromboxane in vitro.

Processing of procorticotropin-releasing hormone (pro-CRH): molecular forms of CRH in normal and preeclamptic pregnancy

This study examined the different molecular forms of CRH in normal and preeclampsia maternal plasma and protease-blocked placental extracts using antibodies to different regions of the CRH precursor, pro-CRH. In the absence of protease inhibitors, chromatographed normal placental extracts contained four peaks of immunoreactivity corresponding to unprocessed approximately 19-kDa pro-CRH, its approximately 8-kDa intermediate metabolite, pro-CRH125-194, its approximately 2.8-kDa midportion fragment, pro-CRH125-151, and 4.75-kDa CRH1-41. However, if protease inhibitors were included in the extraction medium, only pro-CRH and pro-CRH125-194 were found. Pro-CRH processing was more extensive in protease-blocked preeclampsia placentas than in those from normal pregnancy, with three peaks corresponding to pro-CRH, proCRH125-194, and mature CRH1-41 peptide found. Using quantitative competitive PCR, the messenger ribonucleic acid levels of CRH precursor in preeclampsia placentas were 1.7-fold higher than those in normal placentas (37.83 +/- 3.48 vs. 21.83 +/- 2.59 attomoles/microg total ribonucleic acid, respectively; P < 0.005). Preeclampsia placentas contained significantly more CRH1-41 cross-reactivity (4.72 +/- 1.22 pmol/g) than normal term placentas (1.52 +/- 0.39 pmol/g; P < 0.048) extracted in medium containing protease inhibitors. The content of pro-CRH(125+/-151)-reactive species in these extracts followed the same pattern, with more immunoreactivity detected in preeclampsia placentas (4.23 +/- 1.39 pmol/g) than in those from normal term pregnancies (1.44 +/- 0.32 pmol/g; P < 0.01). Sequential plasma samples from 10 women with normal pregnancy and 5 women with preeclampsia were assayed for pro-CRH(125-151)- and CRH(1-41)-immunoreactive species In normal pregnancy, maternal plasma CRH(1-41) immunoreactivity rose with increasing gestational age, reaching 460 +/- 48 pmol/L at term. In women with preeclampsia, CRH(1-41) levels at each gestational age point were higher than those at the equivalent stage of normal pregnancy. In contrast, the levels of pro-CRH(125-151)-immunoreactive species remained barely detectable throughout normal and preeclamptic pregnancy. Both pro-CRH and CRH(1-41), but not pro-CRH(125-151), were shown to bind to the plasma CRH-binding protein. Our findings highlight the importance of protection of placental tissue from degrading enzymes during extraction and show that most of the CRH in the human placenta exists as unprocessed pro-CRH, with very little in the form of CRH(1-41) except in preeclampsia. Our studies using maternal plasma indicate that CRH(1-41) is the only one of the pro-CRH fragments studied to be maintained in significant amounts in the maternal circulation and also the only fragment studied for which a specific plasma binding protein exists.

Potential biochemical growth markers in premature infants

Identification of a biochemical marker of growth in low birth weight (LBW) infants would be of benefit to rapidly assess the effects of illness and/or therapeutic intervention. The aims of the present study were (1) to measure serially the C-terminal fragment of type I procollagen (PICP), bone-specific alkaline phosphatase (BSAP), and osteocalcin (OC) in LBW infants during the first 6 weeks of life; (2) to correlate the changes in PICP, BSAP, and OC with the changes in weight; and (3) to evaluate PICP levels as a marker for bronchopulmonary dysplasia (BPD). Premature neonates (< or =36 weeks of gestation) had cord blood and then weekly blood samples taken from up to 6 weeks after birth. Daily changes in weight were recorded. Measurements of serum PICP, BSAP, and OC were done in duplicate by immunoassay. In a subset population (25-30 weeks), PICP levels in the first 4 weeks of life were evaluated as a marker for subsequent development of BPD. A total of 77 infants had serum PICP and BSAP measured. The mean (+/- SEM) gestational ages of all the infants were 30.4 (+/-0.3) weeks and birth weights 1477 (+/-55) g. Fifteen infants also had measurements of OC done. In these 15 infants, change in weight was correlated significantly with PICP (p<0.0001), but not with either BSAP (p = 0.8) or OC measurements (p = 0.9). In appropriate for gestational age (AGA) infants (n = 66), the PICP values decreased from the cord blood values to the week 1 measurement, coinciding with the fall in weight over the same time period. BSAP values, on the other hand, continued to increase from birth onwards. Over the first 6 weeks of postnatal life in these infants, change in weight had a stronger positive correlation with PICP (R2 = 0.43, p<0.0001) than BSAP (R2 = 0.03, p<0.01). In the subset population, PICP levels at week 4 were significantly lower (p<0.04) in those infants who subsequently developed BPD. PICP measurements are correlated with somatic growth in premature infants and could be used as a biochemical marker in infants who develop BPD.

In vitro human decidual endothelial cell thromboxane secretion in preeclampsia is not abnormal

OBJECTIVES

The aims of this study were to describe levels of thromboxane secretion by decidual endothelial cells from normal pregnancies and to determine whether decidual endothelial cell secretion of thromboxane, implicated in the causation of the hypertension and vasoconstriction of preeclampsia, is increased in this disorder.

METHODS

We measured thromboxane generation by cultured decidual endothelial cells from 13 normal pregnancies (NDEC) and 13 pregnancies complicated by preeclampsia (PEDEC), compared with a control population of 6 normal human umbilical vein endothelial cells (HUVEC). Responses to stimulation by bacterial lipopolysaccharide (LPS), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta) were examined.

MAIN OUTCOME MEASURES

Thromboxane B2 levels in supernatants of cultured endothelial cells.

RESULTS

The level of secretion over 24 h in culture by NDEC [14 (7-26) pg/10(6) cells] was approximately 25% that of HUVEC [63 (49-70) pg/10(6) cells]. Levels achieved in response to all stimuli examined were consistently lower in NDEC than in HUVEC (p < 0.01). Proportional stimulation by LPS and TNF-alpha was comparable in HUVEC and NDEC, whereas NDEC displayed a greater increase (25-fold) than HUVEC (10-fold) in response to IL-1 beta (p < 0.01). There were no significant differences between decidual endothelial cells from normotensive and preeclamptic women in basal secretion of thromboxane or in responses to the stimuli examined.

CONCLUSIONS

In vitro thromboxane secretion by decidual endothelial cells is lower than that of HUVEC, and responsiveness to specific stimuli may be quantitatively different. These findings emphasize the importance of examining endothelial cells from the involved maternal vascular bed if intrauterine vascular pathophysiological events are to be clarified. No significant differences were noted in decidual endothelial cell thromboxane secretion between normal and preeclamptic subjects.

Self-awareness: improving nurse-client interactions

Communication is a key skill of modern nursing practice, yet often it is an area in which nurses fail. Self-awareness exercises can help us to improve our communication skills and enhance healthcare delivery.

Continuous infusion cyclosporine and nifedipine to day +100 with short methotrexate and steroids as GVHD prophylaxis in unrelated donor transplants

Unrelated donor marrow transplantation is associated with an increased incidence of graft-versus-host disease (GVHD) compared with sibling donor transplants. Forty-one patients undergoing unrelated donor transplants were treated with a GVHD prophylaxis regimen that consisted of continuous infusion cyclosporine from day -1 to 100 days post transplant along with nifedipine, glucocorticoids and short-course methotrexate. The regimen was well-tolerated in this cohort with mostly high risk disease. Fifty-one percent of patients developed acute GVHD, which was grade III-IV in 22% of patients. Six of 22 patients at risk for chronic GVHD developed extensive chronic GVHD, five of whom were adults. In patients <18 years of age, there was a >40% chance of 2 year disease-free survival. Use of continuous infusion cyclosporine with nifedipine as an immunosuppressant and protectant against cyclosporine-induced toxicities in unrelated donor transplants is well-tolerated, and results in acute GVHD incidence favorable to that reported with bolus cyclosporine.

Haemodynamic analysis of efficacy of compression hosiery in elderly fallers with orthostatic hypotension

Ten elderly people with orthostatic hypotension and a history of falls were studied by continuous recording of blood pressure and heart rate during passive tilting from supine to 90 degrees head-up tilt. Compression hosiery significantly decreased the change in systolic blood pressure.

Blockade of membrane transport and disassembly of the Golgi complex by expression of syntaxin 1A in neurosecretion-incompetent cells: prevention by rbSEC1

The t-SNAREs syntaxin1A and SNAP-25, i.e. the members of the complex involved in regulated exocytosis at synapses and neurosecretory cells, are delivered to their physiological site, the plasma membrane, when transfected into neurosecretion-competent cells, such as PC12 and AtT20. In contrast, when transfection is made into cells incompetent for neurosecretion, such as those of a defective PC12 clone and the NRK fibroblasts, which have no endogenous expression of these t-SNAREs, syntaxin1A (but neither two other syntaxin family members nor SNAP-25) remains stuck in the Golgi-TGN area with profound consequences to the cell: blockade of both membrane (SNAP-25, GAT-1) and secretory (chromogranin B) protein transport to the cell surface; progressive disassembly of the Golgi complex and TGN; ultimate disappearance of the latter structures, with intermixing of their markers (mannosidase II; TGN-38) with those of the endoplasmic reticulum (calreticulin) and with syntaxin1A itself. When, however, syntaxin 1A is transfected together with rbSec1, a protein known to participate in neurosecretory exocytosis via its dynamic interaction with the t-SNARE, neither the blockade nor the alterations of the Golgi complex take place. Our results demonstrate that syntaxin1A, in addition to its role in exocytosis at the cell surface, possesses a specific potential to interfere with intracellular membrane transport and that its interaction with rbSec1 is instrumental to its physiological function not only at the plasma membrane but also within the cell. At the latter site, the rbSec1-induced conversion of syntaxin1A into a form that can be transported and protects the cell from the development of severe structural and membrane traffic alterations.

Computer generated discharge summaries and their use as a case mix sensitive audit engine. A tale of two cities

BACKGROUND

An 'audit engine' allows critical appraisal of clinical practice without necessitating cumbersome data input, editing or analysis. This is achieved by capturing data from an otherwise necessary task, in this case writing discharge summaries, and using standardised analyses to illustrate the effects of operational changes.

DESIGN AND SETTING

Retrospective analysis of clinical outcome of 1,829 sequential discharges from one consultant's team in two geriatric medicine departments.

MAIN OUTCOME MEASURES

Mortality, discharge destination and functional performance.

RESULTS

Median length of stay in the two departments differed significantly (8 vs 13 days; p < 0.0001), but patients in the latter department were more disabled, with almost twice as many needing domiciliary services after discharge and suffering impaired mobility or incontinence. Despite this disparity, a similar proportion of survivors was placed in institutional care (31/300 (10%) vs 94/1,100 (8%); NS).

CONCLUSIONS

This audit engine demonstrated that apparently worse performance indicators were explained by adverse case mix in one department, and the similar institutionalisation rates suggest superior care there.

Myelodysplastic syndrome and associated skin lesions: a review of the literature

The skin involvement of the myelodysplastic syndrome (MDS) can take the form of either a neoplastic infiltration or various non specific lesions. The occurrence of these lesions may be the presenting feature of the disease (MDS) or may herald its progression to acute leukemia. Recognition and early diagnosis have therapeutic and prognostic significance.

The humoral immune response to human T-cell lymphotropic virus type 1 envelope glycoprotein gp46 is directed primarily against conformational epitopes

Individuals infected with human T-cell lymphotropic virus type 1 (HTLV-1) develop a robust immune response to the surface envelope glycoprotein gp46 that is partially protective. The relative contribution of antibodies to conformation-dependent epitopes, including those mediating virus neutralization as part of the humoral immune response, is not well defined. We assess in this report the relationship between defined linear and conformational epitopes and the antibodies elicited to these domains. First, five monoclonal antibodies to linear epitopes within gp46 were evaluated for their ability to abrogate binding of three human monoclonal antibodies that inhibit HTLV-1-mediated syncytia formation and recognize conformational epitopes. Binding of antibodies to conformational epitopes was unaffected by antibodies to linear epitopes throughout the carboxy-terminal half and central domain of HTLV-1 gp46. Second, an enzyme-linked immunoadsorbent assay was developed and used to measure serum antibodies to native and denatured gp46 from HTLV-1-infected individuals. In sera from infected individuals, reactivity to denatured gp46 had an average of 15% of the reactivity observed to native gp46. Third, serum antibodies from 24 of 25 of HTLV-1-infected individuals inhibited binding of a neutralizing human monoclonal antibody, PRH-7A, to a conformational epitope on gp46 that is common to HTLV-1 and -2. Thus, antibodies to conformational epitopes comprise the majority of the immune response to HTLV-1 gp46, and the epitopes recognized by these antibodies do not appear to involve sequences in previously described immunodominant linear epitopes.

Prostacyclin concentrations and transitional circulation in preterm infants requiring mechanical ventilation

AIM

To describe the association between early postnatal prostacyclin concentrations in preterm infants; echocardiographic measurements of ductal diameter and ventricular output and clinical outcomes of intraventricular haemorrhage (IVH) and patent ductus arteriosus (PDA).

METHODS

Forty nine preterm infants born before 30 weeks of gestational age (median birthweight 980 g, median gestational age 27 weeks) underwent echocardiographic studies at 5, 12, 24 and 48 hours of postnatal age. Measurements included ventricular outputs and the ductal shunt diameter as a measure of the shunt size. Simultaneous measurements of blood pressures, mean airway pressure and inspired fraction of oxygen (FIO2) were recorded. A blood sample for the prostacyclin metabolite 6-ketoprostaglandin F1-alpha (6KPGF1 alpha) was taken at the 5 and 24 hour echocardiogram.

RESULTS

The mean 6KPGF1 alpha concentrations were higher than adult concentrations at 5 (515 pg/ml) and 24 (255 pg/ml) hours. There was no association with gestational age. Raised 6KPGF1 alpha concentrations were related to increased need for mechanical ventilation and severity of respiratory disease. At 5 hours, increased 6KPGF1 alpha concentrations were associated with larger PDA and at 24 hours with larger PDA and higher left ventricular output. Infants with higher 6KPGF1 alpha concentrations were more likely to develop clinically significant PDA. There was no association between early measurements of 6KPGF1 alpha and IVH.

CONCLUSIONS

Early postnatal prostacyclin concentrations are markedly raised in preterm infants, particularly in those with more severe lung disease. Raised 6KPGF1 alpha concentrations were associated with an increased ductal diameter and subsequent PDA, but not IVH.

Risk-factor assessment for falls: from a written checklist to the penless clinic

OBJECTIVE

to audit risk-factor identification of fallers before and after an education programme and the insertion of a written checklist in medical notes. Risk-factor identification in a dedicated, computerized falls clinic was then examined.

METHODS

documentation of risk factors for falls was studied on wards and a self-auditing 'penless' clinic for fallers subsequently set up to generate reports for medical notes and letters for general practitioners.

RESULTS

risk-factor identification improved after the insertion of the checklist but remained relatively poor. A dedicated clinic allowed almost complete identification of risk factors. Of the first 112 patients (median age 82) seen in the clinic, 75 (67%) were housebound. Remediable risk factors--e.g. inappropriate medication (67%), unsatisfactory footwear (59%) and postural hypotension (17%)--were found in most. Thirty-three patients (29%) had difficulty with alarm raising.

CONCLUSION

ward-based intervention showed limited capacity to identify risk factors for falls: a dedicated clinic was more successful. The use of a portable computer with a programme to screen fallers for risk factors is worthy of consideration.