Increased classical monocyte subsets in South Asians compared to White Caucasians at risk for coronary atherosclerosis

Background

South Asians (SA) have an increased prevalence of coronary artery disease (CAD) and myocardial infarction compared with age- and sex-adjusted White Caucasians (WC). The mechanism for this increased risk is poorly understood. While classical CD14++CD16- monocytes act as independent predictors of cardiovascular disease, differences in the distribution of monocyte subsets between SA and WC have not been established.

Purpose

We aimed to determine if differences exist in monocyte subsets between SA and WC at risk for CAD.

Methods

Our cohort consisted of 119 consecutively enrolled patients (59 SA, 60 WC) at intermediate or higher risk for CAD by the INTERHEART score using self-reported history and physical exam. A single blood sample was collected prospectively for the purpose of monocyte analysis. Flow cytometry using dual colour fluorescence (CD14, CD16) within the monocyte gate was used to identify monocyte subsets (classical, intermediate and non-classical) by staff blinded to the individuals' characteristics.

Variables were compared using Mann-Whitney U test and Chi-squared test, as appropriate. Eta coefficient was calculated to analyze the relationship between ethnicity and proportion of monocyte subsets. Eta squared values were calculated to assess the impact of ethnicity on monocyte subset proportions.

Results

The SA group consisted of 64% males with a mean age of 54 (± 9), while the WC group consisted of 55% males with a mean age of 59 (± 7). Both groups had similar body mass index, rates of hypertension, dyslipidemia and family history of premature CAD. Compared to WC, SA had higher prevalence of diabetes (36% vs. 13%, p=0.005) and hemoglobin A1C levels (6.0±1.1% vs. 5.6±0.6%, p<0.001). SA patients had a higher proportion (85.3±10.7% vs. 81.4±11.0%, p=0.009) and total level (449.0±180.4 vs. 388±127.4, p=0.010) of classical CD14++CD16- monocytes compared to WC. There was no difference between the two groups in the proportion of intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes. There was no association between diabetes and the proportion of monocyte subsets. Ethnicity had a moderate association with the proportion of classical CD14++CD16- monocytes (Eta coefficient = 0.525) with a large effect size (Eta squared = 27.5%). The association of ethnicity with intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes was either weak or negligible with minimal to no effect size.

Conclusion

In patients with substantive risk for CAD, SA had a significantly higher proportion and level of classical CD14++CD16- monocytes compared to WC. Our findings provide a novel insight into the potential mechanism of increased CAD susceptibility amongst SA compared to WC. Future studies are needed to determine whether these ethnic differences in the distribution of monocyte subsets can predict susceptibility to developing CAD and suffering atherothrombotic events.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Cardiology Academic Practice Plan grant at the University of British Columbia

Thrombus formation on bioprosthetic aortic valves

Background

18F-GP1 is a novel radiotracer with a high affinity for the platelet glycoprotein IIb/IIIa receptor. Subclinical bioprosthetic valve thrombus has been postulated as a trigger for accelerated valve degeneration.

Purpose

To determine the feasibility of 18F-GP1 positron-emission tomography-computed tomography (PET-CT) for the detection of subclinical bioprosthetic aortic valve thrombus.

Methods

(i) Explanted degenerated aortic valve prostheses underwent histology and imaging. (ii) In a prospective observational study, patients with bioprosthetic aortic valve replacement (AVR) underwent echocardiography and 18F-GP1 PET-CT. Valves were assessed for hypoattenuating leaflet thickening (HALT), hypo-attenuation affection leaflet motion (HAM) and GP1 uptake.

Results

(i) GP1 correlated with thrombus on explanted valves (Figure). (ii) The first 6 patients (Table) were asymptomatic and had normally functioning surgical bioprostheses on echocardiography. At a median of 166 (range 122–189) days post-AVR, no patients had HALT or HAM on CT. There was avid focal GP1 uptake on the leaflets of all 6 patients which appeared most prominent along the leaflet edges (Figure). Only one patient had focal uptake in the valve frame, remote from the leaflets. In a separate cohort undergoing 18F-GP1 PET-CT for other conditions, there was no uptake on normal, native aortic valves (n=8).

Conclusion

For the first time, we demonstrate that 18F-GP1 PET-CT is a highly sensitive method of assessing platelet activation on bioprosthetic aortic valves. Despite the absence of CT evidence, early thrombus appeared to be a universal finding on recently implanted valve prostheses. The biological and clinical implications of subclinical bioprosthetic aortic valve thrombus have yet to be established.

GP1 uptake in AVR

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): British Heart Foundation

Bioprosthetic valve thrombosis and degeneration following transcatheter aortic valve implantation (TAVI)

Bioprosthetic valve thrombosis (BPVT) is a recognised complication of prosthetic aortic valves and can be found in up to 13% of patients after transcatheter implantation. The mechanism of BPVT is not well known, abnormal flow conditions in the new and native sinuses and lack of functional endothelialisation are suspected causes. BPVT may result in valve dysfunction, possibly related to degeneration, and recurrence of patient symptoms, or remain subclinical. BPVT is best diagnosed at multiphase gated computed tomography (CT) angiography as the presence of reduced leaflet motion (RELM) and hypoattenuating aortic leaflet thickening (HALT). Although CT is used to exclude BPVT in symptomatic patients and those with increased valve gradients, the value of screening and prophylactic anticoagulation is debatable.

Factors associated with maternal death from direct pregnancy complications: a UK national case-control study

OBJECTIVE

To investigate the factors associated with maternal death from direct pregnancy complications in the UK.

DESIGN

Unmatched case-control analysis.

SETTING

All hospitals caring for pregnant women in the UK.

POPULATION

A total of 135 women who died (cases) between 2009 and 2012 from eclampsia, pulmonary embolism, severe sepsis, amniotic fluid embolism, and peripartum haemorrhage, using data from the Confidential Enquiry into Maternal Death, and another 1661 women who survived severe complications (controls) caused by these conditions (2005-2013), using data from the UK Obstetric Surveillance System.

METHODS

Multivariable regression analyses were undertaken to identify the factors that were associated with maternal deaths and to estimate the additive odds associated with the presence of one or more of these factors.

MAIN OUTCOME MEASURES

Odds ratios associated with maternal death and population-attributable fractions, with 95% confidence intervals. Incremental risk of death associated with the factors using a 'risk factors' score.

RESULTS

Six factors were independently associated with maternal death: inadequate use of antenatal care (adjusted odds ratio, aOR 15.87, 95% CI 6.73-37.41); substance misuse (aOR 10.16, 95% CI 1.81-57.04); medical comorbidities (aOR 4.82, 95% CI 3.14-7.40); previous pregnancy problems (aOR 2.21, 95% CI 1.34-3.62); hypertensive disorders of pregnancy (aOR 2.44, 95% CI 1.31-4.52); and Indian ethnicity (aOR 2.70, 95% CI 1.14-6.43). Of the increased risk associated with maternal death, 70% (95% CI 66-73%) could be attributed to these factors. Odds associated with maternal death increased by three and a half times per unit increase in the 'risk factor' score (aOR 3.59, 95% CI 2.83-4.56).

CONCLUSIONS

This study shows that medical comorbidities are importantly associated with direct (obstetric) deaths. Further studies are required to understand whether specific aspects of care could be improved to reduce maternal deaths among women with medical comorbidities in the UK.

The management and outcomes of placenta accreta, increta, and percreta in the UK: a population-based descriptive study

Objective To describe the management and outcomes of placenta accreta, increta, and percreta in the UK.

Design A population-based descriptive study using the UK Obstetric Surveillance System (UKOSS).

Setting All 221 UK hospitals with obstetrician-led maternity units.

Population All women diagnosed with placenta accreta, increta, and percreta in the UK between May 2010 and April 2011.

Methods Prospective case identification through the monthly mailing of UKOSS.

Main outcome measures Median estimated blood loss, transfusion requirements.

Results A cohort of 134 women were identified with placenta accreta, increta, or percreta: 50% (66/133) were suspected to have this condition antenatally. In women with a final diagnosis of placenta increta or percreta, antenatal diagnosis was associated with reduced levels of haemorrhage (median estimated blood loss 2750 versus 6100 ml, P = 0.008) and a reduced need for blood transfusion (59 versus 94%, P = 0.014), possibly because antenatally diagnosed women were more likely to have preventative therapies for haemorrhage (74 versus 52%, P = 0.007), and were less likely to have an attempt made to remove their placenta (59 versus 93%, P < 0.001). Making no attempt to remove any of the placenta, in an attempt to conserve the uterus or prior to hysterectomy, was associated with reduced levels of haemorrhage (median estimated blood loss 1750 versus 3700 ml, P = 0.001) and a reduced need for blood transfusion (57 versus 86%, P < 0.001).

Conclusions Women with placenta accreta, increta, or percreta who have no attempt to remove any of their placenta, with the aim of conserving their uterus, or prior to hysterectomy, have reduced levels of haemorrhage and a reduced need for blood transfusion, supporting the recommendation of this practice.

British HIV Association and Children's HIV Association position statement on infant feeding in the UK 2011

To prevent the transmission of HIV infection during the postpartum period, the British HIV Association and Children's HIV Association (BHIVA/CHIVA) continue to recommend the complete avoidance of breast feeding for infants born to HIV-infected mothers, regardless of maternal disease status, viral load or treatment.

Generalized diffusion equation for anisotropic anomalous diffusion

Motivated by studies of comblike structures, we present a generalization of the classical diffusion equation to model anisotropic, anomalous diffusion. We assume that the diffusive flux is given by a diffusion tensor acting on the gradient of the probability density, where each component of the diffusion tensor can have its own scaling law. We also assume scaling laws that have an explicit power-law dependence on space and time. Solutions of the proposed generalized diffusion equation are consistent with previously derived asymptotic results for the probability density on comblike structures.

Why is there a modifying effect of gestational age on risk factors for cerebral palsy?

OBJECTIVE

To investigate risk factors for cerebral palsy in relation to gestational age.

DESIGN

Three case-control studies within a geographically defined cohort.

SETTING

The former Oxfordshire Health Authority.

PARTICIPANTS

A total of 235 singleton children with cerebral palsy not of postnatal origin, born between 1984 and 1993, identified from the Oxford Register of Early Childhood Impairment; 646 controls matched for gestation in three bands: <or=32 weeks; 33-36 weeks; >or=37 weeks.

RESULTS

Markers of intrapartum hypoxia and infection were associated with an increased risk of cerebral palsy in term and preterm infants. The odds ratio (OR) for hypoxia was 12.2 (95% confidence interval 1.2 to 119) at <or=32 weeks and 146 (7.4 to 3651) at >or=37 weeks. Corresponding ORs for neonatal sepsis were 3.1 (1.8 to 5.4) and 10.6 (2.1 to 51.9). In contrast, pre-eclampsia carried an increased risk of cerebral palsy at >or=37 weeks (OR 5.1 (2.2 to 12.0)) but a decreased risk at <or=32 weeks (OR 0.4 (0.2 to 1.0)). However, all infants <or=32 weeks with maternal pre-eclampsia were delivered electively, and their risk of cerebral palsy was no lower than that of other electively delivered <or=32 week infants (OR 0.9 (0.3 to 2.7)). Nearly 60% of <or=32 week controls were delivered after spontaneous preterm labour, itself an abnormal event.

CONCLUSION

Inflammatory processes, including pre-eclampsia, are important in the aetiology of cerebral palsy. The apparent reduced risk of cerebral palsy associated with pre-eclampsia in very preterm infants is driven by the characteristics of the gestation matched control group. Use of the term "protective" in this context should be abandoned.

In vivo persistence of retrovirally transduced murine long-term repopulating cells is not limited by expression of foreign gene products in the fully or minimally myeloablated setting

Many nonmalignant hematologic disorders could potentially be treated by genetic correction of as few as 5-10% of target lineage cells. However, immune system clearance of cells expressing gene products perceived as foreign could be limiting. There is evidence that tolerance to foreign proteins can result when myeloablative conditioning is used, but this limits the overall applicability of such techniques. Therefore, we sought to evaluate the engraftment of hematopoietic stem cells carrying a foreign transgene after low-dose irradiation by comparing in vivo survival of murine long-term repopulating cells (LTRC) transduced with either a retroviral vector expressing the bacterial neomycin phosphotransferase gene (neo) or a vector containing neo gene sequences but modified to prevent protein expression (nonexpression). First, marrow cells from congenic donors were transduced with either vector and transplanted into recipients treated with standard dose irradiation of 800 rads. High-level engraftment and gene marking resulted, without differences in the marking levels or pattern of persistence of the cells between cells transduced with either vector. Low-dose irradiation at 100 rads was tested using higher cell doses. Marking levels as high as 10% overall were obtained, again with no differences between mice receiving cells transduced with the neo versus the nonexpression vectors. To investigate a potentially more immunogenic protein, marrow cells were transduced with a vector containing the green fluorescent protein (GFP) gene, and their persistence was studied in recipient mice receiving 100 rads. Stable GFP expression in 5-10% of circulating cells was observed long term. We conclude that even with very low dose conditioning, engraftment by genetically modified LTRC cells at clinically significant levels can be achieved without evidence for clearance of cells known to be expressing immunogenic proteins.

Avoidance of stimulation improves engraftment of cultured and retrovirally transduced hematopoietic cells in primates

Recent reports suggest that cells in active cell cycle have an engraftment defect compared with quiescent cells. We used nonhuman primates to investigate this finding, which has direct implications for clinical transplantation and gene therapy applications. Transfer of rhesus CD34(+) cells to culture in stem cell factor (SCF) on the CH-296 fibronectin fragment (FN) after 4 days of culture in stimulatory cytokines maintained cell viability but decreased cycling. Using retroviral marking with two different gene transfer vectors, we compared the engraftment potential of cytokine-stimulated cells versus those transferred to nonstimulatory conditions (SCF on FN alone) before reinfusion. In vivo competitive repopulation studies showed that the level of marking originating from the cells continued in culture for 2 days with SCF on FN following a 4-day stimulatory transduction was significantly higher than the level of marking coming from cells transduced for 4 days and reinfused without the 2-day culture under nonstimulatory conditions. We observed stable in vivo overall gene marking levels of up to 29%. This approach may allow more efficient engraftment of transduced or ex vivo expanded cells by avoiding active cell cycling at the time of reinfusion.

Cytomegalovirus urinary excretion and long term outcome in children with congenital cytomegalovirus infection. Congenital CMV Longitudinal Study Group

BACKGROUND

Cytomegalovirus (CMV) is the most frequent cause of congenital infection, and both symptomatic and asymptomatic infants may have long term sequelae. Children with congenital CMV infection are chronically infected and excrete CMV in the urine for prolonged periods. However, the effect of prolonged viral replication on the long term outcome of these children is unknown.

OBJECTIVE

To determine whether duration of CMV excretion is associated with outcome at 6 years of life in symptomatic and asymptomatic congenitally infected children.

METHODS

Longitudinal cohort study. Children congenitally infected with CMV were identified at birth and followed prospectively in a study of long term effects of congenital CMV infection. The relationship between duration of CMV urinary excretion and growth, neurodevelopment and presence and progression of sensorineural hearing loss (SNHL) at 6 years of age was determined.

RESULTS

There was no significant difference in the duration of viral urinary excretion between children born with asymptomatic (median, 4.55 years) and symptomatic (median, 2.97 years) congenital CMV infection (P = 0.11). Furthermore there was no association between long term growth or cognitive outcome and duration of viral excretion. However, a significantly greater proportion of children who excreted CMV for <4 years had SNHL and progressive SNHL compared with children with CMV excretion >4 years (P = 0.019, P = 0.009, respectively).

CONCLUSIONS

Children congenitally infected with CMV are chronically infected for years, but the duration of CMV urinary excretion is not associated with abnormalities of growth, or neurodevelopmental deficits. However, SNHL and progressive SNHL were associated with a shorter duration of CMV excretion.

Measuring infectious bursal disease virus RNA in blood by multiplex real-time quantitative RT-PCR

A quantitative reverse transcription polymerase chain reaction (RT-PCR) protocol for assessing infectious bursal disease virus (IBDV) RNA levels in blood was developed using the ABI PRISM 7700 Sequence Detection System coupled with TaqMan chemistry. To control for variations in sampling and processing between samples 28S rRNA was co-amplified in a multiplex reaction and used to quantify total RNA. Relative quantification and standardisation was achieved using a log10 dilution series of RNA extracted from IBDV stock. A linear relationship was observed between input RNA and cycle threshold values (C(T)) over 5 log10 dilutions for the IBDV-specific product and 6 log10 dilutions for the 28S rRNA-specific product. As a test of the assay it was used to determine whether differences in susceptibility to IBDV observed between inbred lines of chickens could be detected at the level of viral load in the blood. Viral RNA levels peaked 2 days post-infection when there was significantly less viral RNA in the blood of resistant line 6(1) chickens compared with the more susceptible Brown Leghorns (P = 0.01). These results demonstrate that the course of IBDV infection can be monitored by quantifying IBDV RNA extracted from blood of infected chickens using TaqMan technology.

Mesoscopic model for the viscosities of nematic liquid crystals

Based on the definition of the mesoscopic concept by Blenk et al. [Physica A 174, 119 (1991); J. Noneq. Therm. 16, 67 (1991); Mol. Cryst. Liq. Cryst. 204, 133 (1991)] an approach to calculate the Leslie viscosity coefficients for nematic liquid crystals is presented. The approach rests upon the mesoscopic stress tensor, whose structure is assumed similar to the macroscopic Leslie viscous stress. The proposed form is also the main dissipation part of the mesoscopic Navier-Stokes equation. On the basis of the correspondence between microscopic and mesoscopic scales a mean-field mesoscopic potential is introduced. It allows us to obtain the stress tensor angular velocity of the free rotating molecules with the help of the orientational Fokker-Planck equation. The macroscopic stress tensor is calculated as an average of the mesoscopic counterpart. Appropriate relations among mesoscopic viscosities have been found. The mesoscopic analysis results are shown to be consistent with the diffusional model of Kuzuu-Doi and Osipov-Terentjev with the exception of the shear viscosity alpha(4). In the nematic phase alpha(4) is shown to have two contributions: isotropic and nematic. There exists an indication that the influence of the isotropic part is dominant over the nematic part. The so-called microscopic stress tensor used in the microscopic theories is shown to be the mean-field potential-dependent representation of the mesoscopic stress tensor. In the limiting case of total alignment the Leslie coefficients are estimated for the diffusional and mesoscopic models. They are compared to the results of the affine transformation model of the perfectly ordered systems. This comparison shows disagreement concerning the rotational viscosity, whereas the coefficients characteristic for the symmetric part of the viscous stress tensor remain the same. The difference is caused by the hindered diffusion in the affine model case.

Engraftment of MDR1 and NeoR gene-transduced hematopoietic cells after breast cancer chemotherapy

To determine whether the multidrug resistance gene MDR1 could act as a selectable marker in human subjects, we studied engraftment of peripheral blood progenitor cells (PBPCs) transduced with either MDR1 or the bacterial NeoR gene in six breast cancer patients. This study differed from previous MDR1 gene therapy studies in that patients received only PBPCs incubated in retroviral supernatants (no nonmanipulated PBPCs were infused), transduction of PBPCs was supported with autologous bone marrow stroma without additional cytokines, and a control gene (NeoR) was used for comparison with MDR1. Transduced PBPCs were infused after high-dose alkylating agent therapy and before chemotherapy with MDR-substrate drugs. We found that hematopoietic reconstitution can occur using only PBPCs incubated ex vivo, that the MDR1 gene product may play a role in engraftment, and that chemotherapy may selectively expand MDR1 gene-transduced hematopoietic cells relative to NeoR transduced cells in some patients.

Expression of interferon-gamma by stromal cells inhibits murine long-term repopulating hematopoietic stem cell activity

Several lines of evidence suggest that overexpression of interferon gamma (IFN-gamma) in the marrow microenvironment may play a role in the pathogenesis of marrow suppression in aplastic anemia. We previously showed that overexpression of IFN-gamma by marrow stromal cells inhibits human long-term culture initiating cell activity assayed in vitro to a much greater degree than the addition of soluble IFN-gamma. The effect of IFN-gamma on true repopulating stem cells assayed in vivo has not been studied previously. We compared the effect of co-culture of murine marrow cells in the presence of stromal cells transduced with a retroviral vector expressing murine IFN-gamma vs stromal cells transduced with a control neo vector. Using a murine congenic competitive repopulation assay, there was significantly less long-term repopulating stem cell activity remaining after culture on mIFN-gamma-expressing stroma as compared to control stroma. We also investigated the effect of directly transducing murine bone marrow cells with the mIFN-gamma or control vector. Marrow cells transduced with either vector were transplanted into W/Wv recipient mice. The percentage of vector-containing cells in the mIFN-gamma mice was significantly lower than in the control mice, suggesting that mIFN-gamma-transduced primitive cells may not have survived culture, or that mIFN-gamma directly decreases gene transfer into repopulating cells. Despite no significant differences in white or red blood cells in the mice transplanted with the mIFN-gamma-transduced cells, the number of bone marrow colony-forming unit-C 16 weeks after transplantation was significantly lower in the IFN-gamma group. These data indicate that ectopic or overexpression of mIFN-gamma, especially by marrow microenvironmental elements, may have a marked effect on primitive hematopoiesis as assayed in vivo.

Sequential neuromotor examination in children with intrauterine cocaine/polydrug exposure

Data are presented on 157 newborn infants followed sequentially in a randomized home-based nursing-intervention trial for drug-exposed infants with follow up at 3 (N=118), 6 (N=124), and 12 months (N=77). The objectives of this study were to describe the longitudinal neurodevelopmental status of a cohort of children with intrauterine exposure to illicit drugs during their gestation, characterize the evolution of early tone abnormalities in a polydrug-exposed cohort, and determine whether neuromotor outcome is associated with drug-exposure patterns. For analysis, infants were grouped based on maternal drug-use pattern and the presence of drug metabolites in the neonatal drug screen. The sequential neuromotor examination was used at each age to define the neuromotor status of six domains and define categorical classifications as either normal, suspect, or abnormal. Multiple patterns of neuromotor abnormalities were observed during the neonatal period; most resolved over time. Axial hypotonia was a prominent finding in the neonatal period; however, it was infrequent in abnormal examinations at 12 months. Increased lower-extremity tone was a less frequent finding during the neonatal period. Infants whose neonatal urine drug screen was positive for both cocaine and opiates, were more likely than infants with negative urine drug screens, cocaine only, or opiate only drug screen results to have abnormal neuromotor examinations; while positive maternal drug screens for concurrent cocaine and opiate use were associated with peripheral hypertonia. Persistence of increased leg-extensor tone was found in 67% of the abnormal examinations at 12 months. Acquisition of rolling and walking was delayed in the drug-exposed cohort.

Transduction of hematopoietic stem cells in humans and in nonhuman primates

Primitive hematopoietic progenitor and stem cells have been pursued as highly desirable targets for genetic therapy. Retroviral vectors have been used for the majority of preclinical and clinical studies directed at these cells; however, both preclinical and early clinical studies indicate that the gene transfer efficiency of the current generation of vectors using known transduction conditions into primate and human repopulating stem cells is too low to be of clinical utility in most situations. In this presentation I will summarize the status of our completed and ongoing clinical genetic marking trials, and describe our efforts in the laboratory and use of primate transplantation models to improve on these results.

The Iowa Articulation Story. Collaboration works

Historically, Iowa has had a majority of diploma and associate degree nursing graduates. Although educational mobility for registered nurses to obtain baccalaureate nursing degrees was available in Iowa before 1991, direct nursing education articulation did not exist. The impetus for developing a statewide nursing articulation plan to facilitate the entry of registered nurses to baccalaureate nursing programs was the result of a recommendation from the Iowa Board of Nursing's 1988 Statewide Plan for Nursing. The Iowa Articulation Plan for Nursing Education: RN to Baccalaureate, implemented in 1991, resulted from collaboration among nurse educators from all levels of nursing and nursing service representatives. The plan consists of four separate options and can be adapted for use in other parts of the country. The Iowa articulation story describes the process used and outcomes achieved when nurses collaborate to advance nursing education.

Improved retroviral gene transfer into murine and Rhesus peripheral blood or bone marrow repopulating cells primed in vivo with stem cell factor and granulocyte colony-stimulating factor

In previous studies we showed that 5 days of treatment with granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF) mobilized murine repopulating cells to the peripheral blood (PB) and that these cells could be efficiently transduced with retroviral vectors. We also found that, 7-14 days after cytokine treatment, the repopulating ability of murine bone marrow (BM) increased 10-fold. In this study we examined the efficiency of gene transfer into cytokine-primed murine BM cells and extended our observations to a nonhuman primate autologous transplantation model. G-CSF/SCF-primed murine BM cells collected 7-14 days after cytokine treatment were equivalent to post-5-fluorouracil BM or G-CSF/SCF-mobilized PB cells as targets for retroviral gene transfer. In nonhuman primates, CD34-enriched PB cells collected after 5 days of G-CSF/SCF treatment and CD34-enriched BM cells collected 14 days later were superior targets for retroviral gene transfer. When a clinically approved supernatant infection protocol with low-titer vector preparations was used, monkeys had up to 5% of circulating cells containing the vector for up to a year after transplantation. This relatively high level of gene transfer was confirmed by Southern blot analysis. Engraftment after transplantation using primed BM cells was more rapid than that using steady-state bone marrow, and the fraction of BM cells saving the most primitive CD34+/CD38- or CD34+/CD38dim phenotype increased 3-fold. We conclude that cytokine priming with G-CSF/SCF may allow collection of increased numbers of primitive cells from both the PB and BM that have improved susceptibility to retroviral transduction, with many potential applications in hematopoietic stem cell-directed gene therapy.

Clinical associations and time of onset of cerebral white matter damage in very preterm babies

Neuropathological examinations were carried out at necropsy on 83 very pre-term babies who died during their first hospital admission. Forty seven (57%) babies had evidence of cerebral damage-39 with ischaemic white matter damage. The time of onset of ischaemic lesions was thought to be prenatal in 12 cases (31%) and postnatal in a further 12 (31%). The exact timing of damage could not be determined in 15 (38%) cases. Maternal and neonatal case notes were reviewed to ascertain clinical associations of ischaemic white matter damage. There were no clear associations between adverse clinical factors and prenatal ischaemic white matter damage. In contrast, pre-eclampsia, intrauterine growth retardation, and delivery without labour were associated with postnatal damage as were neonatal sepsis, necrotising enterocolitis, and seizures. The absence of a clear association between the timing of adverse clinical factors and the timing of ischaemic cerebral damage suggests that cerebral damage in very preterm babies may result from a sequence of events rather than one specific insult.

Case-control study of antenatal and intrapartum risk factors for cerebral palsy in very preterm singleton babies

The increase in survival of very preterm babies during the 1980s was accompanied by a sharp increase in the rate of cerebral palsy in this group. The relation between antenatal and intrapartum factors and cerebral palsy in such babies has not been well defined. To identify adverse and protective antenatal and intrapartum factors we undertook a case-control study of 59 very preterm babies who developed cerebral palsy, identified from a population-based register, and 234 randomly selected controls. The frequency of cerebral palsy decreased with increasing gestational age and birthweight. Antenatal complications occurred in 215 (73%) of the women with preterm deliveries. Factors associated with an increased risk of cerebral palsy after adjustment for gestational age were chorioamnionitis (odds ratio 4.2 [95% CI 1.4-12.0]) prolonged rupture of membranes (2.3 [1.2-4.2]), and maternal infection (2.3 [1.2-4..5]). Pre-eclampsia was associated with a reduced risk of cerebral palsy (0.4 [0.2-0.9]), as was delivery without labour (0.3 [0.2-0.7]). There was no increased risk of cerebral palsy with intrauterine growth retardation (1.0 [0.9-1.1]). The effect of rigorous management of adverse antenatal factors on the frequency of cerebral palsy in very preterm babies should be tested in randomised controlled trials.

Model to identify potentially preventable cerebral palsy of intrapartum origin

A six stage model was applied to a geographically defined population of 210 singleton children born at term who had a diagnosis of cerebral palsy at 5 years of age. Thirty five children were identified as those most likely to have cerebral palsy of intrapartum origin; in 26 of these there was evidence of suboptimal care. It is suggested that this simple model should be tested on populations of children with cerebral palsy and the underlying principles used when considering the likely cause of cerebral palsy in individual children.

Long-term in vivo expression of the human glucocerebrosidase gene in nonhuman primates after CD34+ hematopoietic cell transduction with cell-free retroviral vector preparations

Successful gene transfer into stem cells would provide a potentially useful therapeutic modality for treatment of inherited and acquired disorders affecting hematopoietic tissues. Coculture of primate bone marrow cells with retroviral producer cells, autologous stroma, or an engineered stromal cell line expressing human stem cell factor has resulted in a low efficiency of gene transfer as reflected by the presence of 0.1-5% of genetically modified cells in the blood of reconstituted animals. Our experiments in a nonhuman primate model were designed to explore various transduction protocols that did not involve coculture in an effort to define clinically useful conditions and to enhance transduction efficiency of repopulating cells. We report the presence of genetically modified cells at levels ranging from 0.1% (granulocytes) to 14% (B lymphocytes) more than 1 year following reconstitution of myeloablated animals with CD34+ immunoselected cells transduced in suspension culture with cytokines for 4 days with a retrovirus containing the glucocerebrosidase gene. A period of prestimulation for 7 days in the presence of autologous stroma separated from the CD34+ cells by a porous membrane did not appear to enhance transduction efficiency. Infusion of transduced CD34+ cells into animals without myeloablation resulted in only transient appearance of genetically modified cells in peripheral blood. Our results document that retroviral transduction of primate repopulating cells can be achieved without coculture with stroma or producer cells and that the proportion of genetically modified cells may be highest in the B-lymphoid lineage under the given transduction conditions.

Steroid hormone regulation of rat myometrial gap junction formation: effects on cx43 levels and trafficking

The formation of myometrial gap junctions coincides with onset of labor in many mammalian species, including humans. The assembly of gap junction protein into functional gap junction plaques is a final step in a cascade that begins with estrogen-dependent expression of the connexin43 (cx43) gene and continues with synthesis of cx43 in the rough endoplasmic reticulum (RER) and transport to the Golgi, followed by its trafficking to the plasma membrane and its assembly into functional gap junctions. Moreover, in several models of preterm labor in rats, precocious synthesis, trafficking, and assembly of cx43 follow an increase in the estrogen:progesterone ratio. The actions of these steroids on cx43 expression, gap junction formation, and labor led us to consider whether or not the cascade of cx43 expression and gap junction assembly typical of preterm and term labor would be disrupted by manipulations that inhibit labor through experimental reduction of the estrogen:progesterone ratio. Ovariectomized and non-ovariectomized pregnant rats were treated with minimal doses of progesterone or the anti-estrogenic compound ICI 182780 over a time course sufficient to inhibit labor. We found that cx43-positive gap junction formation was prevented in all animals treated with ICI 182780 or progesterone but that the mechanism by which this disruption occurred was different in anti-estrogen- and progesterone-treated animals. We found that ICI 182780 significantly inhibited the typical rise in myometrial cx43 concentrations normally observed just before labor. In contrast, it was surprising to find that significant cx43 was synthesized in myometrium of progesterone-treated intact and ovariectomized animals even though labor was inhibited. However, we found that the trafficking of myometrial cx43 from the Golgi and assembly into gap junctions at the plasma membrane were suppressed in these progesterone-treated animals, providing further support for the hypothesis that it is not synthesis of cx43 per se but trafficking of cx43 to the plasma membrane and its assembly into gap junctions that are required for effective synchronized myometrial contractions typical of labor.

Cerebral palsy and neonatal encephalopathy

A retrospective cohort study was carried out to test the hypothesis that children born at term with cerebral palsy with signs of neurological dysfunction preceded by depression at birth (termed neonatal encephalopathy) differ from those without such signs in the frequency of antenatal and perinatal factors, and in the severity and characteristics of their impairment and disability. The study was carried out in the area covered by Oxford Regional Health Authority. Antenatal, intrapartum, neonatal factors, and the later clinical status of the two groups of children were used as the main outcome measures. Although most maternal and antenatal characteristics were similar in the two groups, the mothers of children with a history of neonatal encephalopathy were more likely to be primigravidae (odds ratio (OR) 2.0; 95% confidence interval (CI) 1.0 to 4.3) and to have a pregnancy of greater than 41 weeks' gestation (OR 3.5; 95% CI 1.0 to 12.1). Intrapartum complications were more frequent in the neonatal encephalopathy group: meconium staining of the amniotic fluid (OR 3.5; 95% CI 1.5 to 7.8), an ominous first stage cardiotocograph (OR 10.2; 95% CI 2.9 to 36.4), with a longer median duration of abnormality (200 v 48 minutes). At 5 years of age those with neonatal encephalopathy were more likely to have developed spastic quadriplegia (OR 4.8; 95% CI 2.2 to 10.5), to have visual impairment (OR 3.0; 95% CI 1.0 to 8.6), and to be non-walking (OR 4.0; 95% CI 1.8 to 8.8) than those without neonatal encephalopathy. Children with cerebral palsy who were born at term and have neonatal encephalopathy are more likely to have had signs of intrapartum asphyxia and are more likely to have a more severe form of cerebral palsy than those without a history of neonatal encephalopathy. Although this group represents only one in 10 of all cases of cerebral palsy, some of these may be obstetrically preventable.

Case-control study of intrapartum care, cerebral palsy, and perinatal death

OBJECTIVE

To investigate the relation between suboptimal intrapartum obstetric care and cerebral palsy or death.

DESIGN

Case-control study.

SETTING

Oxford Regional Health Authority.

SUBJECTS

141 babies who subsequently developed cerebral palsy and 62 who died intrapartum or neonatally, 1984-7. All subjects were born at term of singleton pregnancies and had no congenital anomaly. Two controls, matched for place and time of birth, were selected for each index case.

MAIN OUTCOME MEASURES

Adverse antenatal factors and suboptimal intrapartum care (by using predefined criteria).

RESULTS

Failure to respond to signs of severe fetal distress was more common in cases of cerebral palsy (odds ratio 4.5; 95% confidence interval 2.4 to 8.4) and in cases of death (26.1; 6.2 to 109.7) than among controls. This association persisted even after adjustment for increased incidence of a complicated obstetric history in cases of cerebral palsy. Neonatal encephalopathy is regarded as the best clinical indicator of birth asphyxia; only two thirds (23/33) of the children with cerebral palsy in whom there had been a suboptimal response to fetal distress, however, had evidence of neonatal encephalopathy; these 23 formed 6.8% of all children with cerebral palsy born to residents of the region in the four years studied.

CONCLUSION

There is an association between quality of intrapartum care and death. The findings also suggest an association between suboptimal care and cerebral palsy, but this seems to have a role in only a small proportion of all cases of cerebral palsy. The contribution of adverse antenatal factors in the origin of cerebral palsy needs further study.

Clinical associations of prenatal ischaemic white matter injury

Neuropathological examinations were carried out at necropsy on 274 cases of intrauterine death or neonatal death at or before three days after birth. Fifty six (20.4%) subjects had evidence of prenatal ischaemic brain damage. On review of the maternal case notes to ascertain antenatal clinical associations there was an increased incidence of intrauterine growth retardation, either based on birth weight for gestational age (odds ratio (OR) 2.0; 95% confidence interval (CI) 1.1 to 3.7) or diagnosed antenatally (OR 2.7; 95% CI 1.3 to 5.6). Oligohydramnios was also more common (OR 2.9; 95% CI 1.2 to 7.0). The association of intrauterine growth retardation and white matter damage remained after excluding fetuses with a major congenital anomaly (OR 2.4; 95% CI 1.1 to 5.1). The findings suggest that chronic intrauterine hypoxia may be associated with damage to cerebral white matter among fetuses and infants who die. The relation between ischaemic white matter damage and cerebral palsy among survivors remains speculative.

Congenital heart block with hydrops fetalis treated with high-dose dexamethasone; a case report

A 32-year-old woman with systemic lupus erythematosus was found to have a fetus with heart block and fetal ascites at 23 weeks gestation. Treatment with high-dose corticosteroids ameliorated the early signs of heart failure, although the fetal heart rate gradually fell from 48 beats/min to 42 beats/min by 34 weeks. Sudden deterioration of the fetal state occurred at 35 weeks, and this only partially responded to digitalisation. Neonatal death occurred on Day 18 from the consequences of severe birth asphyxia. The relationship and pathogenesis of anti-Ro antibodies, congenital heart block and hydrops fetals are discussed, together with the in utero management of this condition.

Augmentation of lung antineutrophil elastase capacity with recombinant human alpha-1-antitrypsin

To evaluate the potential use of recombinant DNA-produced alpha-1-antitrypsin (alpha-1-AT) to augment the lung antineutrophil elastase defenses in alpha-1-AT deficiency, we compared the kinetics of intravenously administered recombinant produced alpha-1-AT (r alpha-1-AT) and purified normal human plasma alpha-1-AT (p alpha-1-AT) in the blood and lung of rhesus monkeys. The r alpha-1-AT was produced in yeast transformed with an expressing plasmid containing a full-length human alpha-1-AT complementary deoxyribonucleic acid and purified to greater than 99% homogeneity. The r alpha-1-AT has a molecular weight of 45,000, no carbohydrates, and is identical in sequence to normal plasma alpha-1-AT except for an additional N-terminal acetylmethionine. Despite its lack of carbohydrates, the r alpha-1-AT inhibited human neutrophil elastase with an association rate constant similar to that of p alpha-1-AT. Rhesus monkeys were infused intravenously with 120 mg/kg of r alpha-1-AT (n = 13) or p alpha-1-AT (n = 12) and the serum, urine, and lung epithelial lining fluid (ELF) concentrations of these molecules quantified at various intervals.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of alveolar macrophages in normals and individuals with active pulmonary sarcoidosis for the spontaneous expression of the interleukin-1 beta gene

We have evaluated the hypothesis that the presence of large numbers of activated helper/inducer T lymphocytes in the lungs of individuals with active pulmonary sarcoidosis is associated with the exaggerated release of interleukin-1 (IL-1) by alveolar macrophages. Evaluation of media from unstimulated cultured sarcoid alveolar macrophages failed to detect IL-1 activity. When parallel cultures of sarcoid and normal alveolar macrophages were stimulated with lipopolysaccharide (LPS), they released similar amounts of IL-1 activity. Using a highly specific polyclonal anti-IL-1 beta antibody and flow cytometry to evaluate cell-associated IL-1 beta, analysis of fresh alveolar macrophages from patients with active sarcoidosis and normal individuals revealed no detectable cell-associated IL-1 beta, but IL-1 beta was present when macrophages from sarcoid patients and normals were stimulated with LPS. Similar observations were made using immunoblot analysis of cell lysates of the same unstimulated and stimulated macrophages. Finally, Northern analysis of alveolar macrophages for IL-1 beta mRNA transcripts demonstrated minimal, but equivalent, amounts of IL-1 beta in both normal and sarcoid macrophages, as compared to the much larger quantities present in LPS-stimulated alveolar macrophages. Thus, while alveolar macrophages of individuals with sarcoidosis are clearly capable of expressing the IL-1 beta gene, these findings suggest that altered expression of the IL-1 beta gene by alveolar macrophages does not play a central role in the exaggerated lung T-cell activation characteristic of sarcoidosis.