bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased c‐Fos protein in the brains of scrapie‐infected SAMP8, SAMR1, AKR and C57BL mice
Authors: Ye X. , Meeker H. C. , Kozlowski P. , Carp R. I.
Published: March 2003

Scrapie is a neurodegenerative disease that occurs naturally in sheep and goats. The histopathological changes include vacuolation, neuronal apoptosis and astrocytosis. The mechanisms involved in neuronal apoptosis are still unknown. Recently, we observed that activated p38 immunohistostaining was increased in scrapie‐infected mice. In many neurodegenerative diseases, activation of the p38 pathway and of the immediate‐early gene termed c‐Fos appears to be required for the initiation of apoptosis. There are similarities in histopathological changes seen in scrapie‐infected mice and in an uninfected senescence‐accelerated mouse strain (SAMP8). This led us to investigate c‐Fos protein levels in the brains of both uninfected and scrapie‐infected SAMP8, SAMR1, AKR and C57BL mice using immunohistochemical methods. The SAMR1 strain served as a control in that it is a mouse strain that does not show accelerated ageing, but has a background that is similar to the SAMP8 strain. AKR was used because it is one of the progenitor strains of both SAM strains and, finally, C57BL is a completely unrelated strain. The results showed a low basal c‐Fos expression in controls and a marked increase in c‐Fos staining in scrapie‐infected mice. In scrapie‐positive mice, c‐Fos immunoreactivity was observed in neurones in the cortex, hippocampus, thalamus, hypothalamus, medulla, midbrain, brainstem, paraterminal body, internal capsule and cerebellar Purkinje cells. Immunoreactivity of c‐Fos was also observed in astrocytes in many brain areas of scrapie‐infected mice, particularly in the hippocampus and cortex. Our results show that normal mouse brain (NMB)‐injected AKR and SAMP8 mice had more c‐Fos production than NMB‐injected SAMR1 or C57BL mice; scrapie‐infection induces significant increases in c‐Fos immunoreactivity in all four mouse strains. Our study suggests that the increase in c‐Fos levels may play a role in the neuronal apoptosis observed in scrapie‐infected mice.
Restoration of dystrophin expression in cultured hybrid myotubes
Authors: Radojevic V. , Oppliger C. , Gaschen F. , Burgunder J.‐M.
Published: March 2003

Absence of dystrophin, as found in Duchenne boys, mdx mice and HFMD cats, leads to destabilization of the sarcolemmal‐associated protein complex. Gene and cell therapy strategies aim to restore the dystrophin‐associated protein complex. In order to better understand the cellular events involved in such therapy in feline and human muscular dystrophy, we asked whether dystrophin‐deficient myoblasts would fuse with myoblasts expressing normal dystrophin, and whether the complex would be restored after such a fusion. Cat and human myoblasts were isolated from skeletal muscle of normal subjects and of patients with dystrophin deficiency and proliferated well. After co‐culture with normal myoblasts, they fused to form hybrid myotubes. These hybrid myotubes expressed dystrophin, utrophin and dystrophin‐ associated proteins. Expression of these proteins were restored also in the vicinity of nuclei from dystrophin‐deficient donors. These results demonstrate that dystrophin can be expressed and handled normally by hybrid myotubes. They show that myoblasts with a normal dystrophin gene can restore dystrophin expression in dystrophin‐deficient myoblasts.
The glial precursor proteoglycan, NG2, is expressed on tumour neovasculature by vascular pericytes in human malignant brain tumours
Authors: Chekenya M. , Enger P. Ø. , Thorsen F. , Tysnes B. B. , Al‐Sarraj S. , Read T. A. , Furmanek T. , Mahesparan R. , Levine J. M. , Butt A. M. , Pilkington G. J. , Bjerkvig R.
Published: March 2003

Glial precursor cells express NG2 and GD3 in the developing brain. These antigens are both over‐expressed during neoplasia, which suggests they may have specific functions in the malignant progression of human brain tumours. This study describes the expression of NG2 and GD3 in 28 paediatric and adult brain tumours. Glioblastoma biopsy spheroids were also implanted into nude rats to assess the regional distribution of the molecules within the tumour. These xenografts showed extensive infiltration and growth that mimicked the growth patterns of human gliomas in situ. NG2 was identified in 20 out of 28 brain tumours, where the expression was confined to the main mass of the tumour, and was reduced towards the tumour periphery. NG2 was mainly associated with blood vessels on both the pericyte and basement membrane components of the tumour vasculature. Ki67 (MIB‐1) labelling indicated that NG2 expression was associated with areas of high cellular proliferation. Conversely, all the tumours expressed GD3, which was present both in the tumour main mass and throughout the periphery. Thus, the expression of NG2 may be indicative of tumour progression and might be an amenable target for future therapeutic interventions.
Abnormal endothelial tight junctions in active lesions and normal‐appearing white matter in multiple sclerosis
Authors: McQuaid S. , Plumb J. , Mirakhur M. , Kirk J.
Published: March 2003

Introduction:  Increased blood–brain barrier permeability is a feature of new and expanding inflammatory lesions in multiple sclerosis (MS). The pathological mechanism for this increased permeability has not been demonstrated.

Materials and methods:  Frozen sections from neuropathologically characterized active plaques and normal‐appearing white matter (NAWM) areas in 13 cases of MS were graded according to the relative abundance of oil‐red O (ORO)‐positive cells. Using single and double immunofluorescence and confocal scanning laser microscopy, the tight junction (TJ)‐associated proteins ZO‐1 and occludin were examined in relation to endothelial integrity (Ulex), blood–brain barrier (BBB) leakage (fibrinogen), lymphocytic infiltration and macrophage/microglial activation (HLA‐DR). Blood vessels (10–50 per section) were systematically scanned to acquire image data sets for offline analysis.

Results:  TJ abnormalities (i.e. beading, interruption or absence of fluorescence, separation or opening of junctions) were frequent (affecting 40% of vessels) in ORO‐positive active plaques, but less frequent in NAWM (<15%) and in normal (2%) and neurological controls (<6%). ‘Open’ junctions were seen both in active ORO‐positive lesions and in inflamed blood vessels in NAWM.

Conclusions:  These results suggest that disrupted TJs, arising during the acute inflammatory phase of MS, could be responsible for much of the BBB leakage seen in enhancing MRI lesions in vivo.
Current status of laboratory diagnosis of subarachnoid haemorrhage in Northern Ireland
Authors: Wallace I. , Sharpe P. , Mirakhur M.
Published: March 2003

Studies have shown that computed tomography (CT) scanning is 95% positive in patients scanned within 1 day of a suspected subarachnoid haemorrhage (SAH). However, generalized cerebral oedema can cause false‐positive diagnosis of SAH on CT, while it is estimated that up to 2% of patients with SAH can have negative scans as a result of the small amounts of subarachnoid blood involved. Because of the risks involved, there is a reluctance to identify aneurysms in CT‐negative patients by cerebral angiography without the supportive evidence of spectrophotometric examination of cerebrospinal fluid (CSF). CSF spectrophotometry is widely regarded as the best technique available for diagnosis of SAH and has replaced the visual inspection of CSF for xanthochromia that many accept as being inadequate. The test is now being carried out in an increasing number of centres throughout the UK and, in Northern Ireland, five hospital laboratories are involved in monitoring its performance by regional audit and a pilot NEQAS scheme. These have identified the limitations of CSF spectrophotometry, one of which is the time it takes for blood pigments to appear in the CSF, and has standardized issues of specimen requirements, laboratory procedures and the level of interpretation when reporting results.
A new technique, which clearly distinguishes fibre types in fixed muscle tissue
Authors: Behan W. M. H. , Cossar D. W. , Madden H. A. , McKay I. C.
Published: March 2003

Aims:  A method of distinguishing between type 1 and 2 skeletal muscle fibres in wax‐embedded tissue is needed. The ATPase method is the basis for fibre identification on frozen tissue and a new method should not give significantly different results. Isoforms of myosin and myofibrillar ATPase are known to correlate.

Materials and methods:  We devised an immunohistochemical double‐labelling (IHC) protocol using monoclonal antibodies to fast and slow myosin. We compared results in the two methods by morphometric analysis of frozen muscle and then applied the method to paraffin‐embedded tissue.

Results:  On frozen sections there were no significant differences (P = 0.57) in the percentages of type 1 (46% IHC method vs. 48% ATPase) or type 2 fibres (54% vs. 52%) and 2a and 2b subtypes were distinguished easily. Cross‐sectional area (in µm2), diameter (µm) and form factor were all similar. Various diagnostic samples of wax embedded tissue were then examined. These gave excellent results with clear colour contrast: type 1 fibres, black and type 2 fibres, red (see examples).

Conclusion:  An IHC method based on the fast and slow isoforms of myosin gives similar results to the ATPase method while providing an important advantage in its applicability to wax‐embedded muscle.
Dural haemorrhage in non‐traumatic infant deaths: does it explain the bleeding in ‘shaken baby syndrome’?
Authors: Geddes J. F. , Tasker R. C. , Hackshaw A. K. , Nickols C. D. , Adams G. G. W. , Whitwell H. L. , Scheimberg I.
Published: March 2003

J. F. Geddes, R. C. Tasker, A. K. Hackshaw, C. D. Nickols, G. G. W. Adams, H. L. Whitwell and I. Scheimberg (2003) Neuropathology and Applied Neurobiology 29, 14–22

 Dural haemorrhage in non‐traumatic infant deaths: does it explain the bleeding in ‘shaken baby syndrome’?

A histological review of dura mater taken from a post‐mortem series of 50 paediatric cases aged up to 5 months revealed fresh bleeding in the dura in 36/50, the bleeding ranging from small perivascular haemorrhages to extensive haemorrhage which had ruptured onto the surface of the dura. Severe hypoxia had been documented clinically in 27 of the 36 cases (75%). In a similar review of three infants presenting with classical ‘shaken baby syndrome’, intradural haemorrhage was also found, in addition to subdural bleeding, and we believe that our findings may have relevance to the pathogenesis of some infantile subdural haemorrhage. Recent work has shown that, in a proportion of infants with fatal head injury, there is little traumatic brain damage and that the significant finding is craniocervical injury, which causes respiratory abnormalities, severe global hypoxia and brain swelling, with raised intracranial pressure. We propose that, in such infants, a combination of severe hypoxia, brain swelling and raised central venous pressure causes blood to leak from intracranial veins into the subdural space, and that the cause of the subdural bleeding in some cases of infant head injury is therefore not traumatic rupture of bridging veins, but a phenomenon of immaturity. Hypoxia with brain swelling would also account for retinal haemorrhages, and so provide a unified hypothesis for the clinical and neuropathological findings in cases of infant head injury, without impact or considerable force being necessary.
Risk factors for infant mortality in Down’s syndrome: a nationwide study
Authors: Sadetzki  , Chetrit  , Akstein  , Luxenburg  , Keinan  , Litvak  , Modan
Published: March 2003

The aim of this study was to assess risk factors for the excessive infant mortality rates (IMR) of infants with Down’s syndrome (DS). The study population included all 847 Jewish DS births in Israel during 1979–83 and 1987–91. Cases were identified through the National DS Registry. Data were abstracted from hospitalisation records. Ninety‐one per cent of the DS diagnoses were confirmed by a cytogenetic analysis. The DS IMR were 24.3 times higher than in the general population. Major risk factors affecting DS IMRs were health status, time period of birth and residential arrangement of the infant. Other known risk factors for infant mortality, such as young maternal age, high birth order and low birthweight, had a weaker impact on IMR in the DS population. Our results imply that the current better survival of infants with DS is a function of the changing attitude towards this population. The study identifies a potential for further reduction in the mortality rates of DS infants, provided there is willingness to adopt a more active and supportive treatment and further changes in ethical codes of the public.
Childhood brain tumours and exposure to animals and farm life: a review
Authors: Yeni‐Komshian H. , Holly E.A.
Published: March 2003

Brain tumours are the most common solid tumour in children. However, little is known about their aetiology, and only a small percentage of cases can be attributed to established risk factors. Exposure to farm animals and pets have been considered as possible risk factors for childhood brain tumour (CBT) development for several reasons. Numerous factors associated with farm life, including bacteria, pesticides, solvents and some animal oncogenic viruses, have been found to induce brain tumour formation in animals. Some studies have found viral gene sequences in human brain tumours. Epidemiological studies of brain tumours in adults have reported an increased risk among veterinarians and farmers. In this review, data are examined from seven case–control studies published between 1979 and 1998 that considered a possible relationship between fetal or childhood exposure to farm animals or pets and CBT. Five of the seven studies examined childhood farm residence or exposure of mother or child to farm animals and, of these five, four reported elevated risk for CBT with odds ratios (OR) ranging from 0.9 to 2.5 for maternal exposures and from 0.6 to 6.7 for children’s exposures. Later studies that were larger subsequently examined histological type and reported excess risk for primitive neuroectodermal tumours (PNETs) with farm residence prenatally (OR = 3.7, CI = 0.8, 24) or in childhood (OR = 5.0, CI = 1.1, 4.7). Increased risk of PNET was also associated with maternal exposure to pigs (OR = 12, CI = 1.1, 47) or poultry (OR = 4.0, CI = 1.2, 13). The results of these studies showed few other consistent relationships between farm life or farm animals and CBT.
Stress and preterm delivery: a conceptual framework
Authors: Hogue Carol J.R. , Hoffman Susie , Hatch Maureen C.
Published: March 2003

Numerous epidemiological studies of various kinds of stress and preterm delivery have produced either negative or weakly positive results. Those inconclusive findings could be either because of the absence of an association or because of recognised methodological problems that may have masked an association. The biological plausibility of the stress hypothesis provides one rationale for continuing stress research, using better study designs. To further this agenda, we propose an epidemiological model, based on the classic ‘host, environment, agent’ triangle of epidemiological causality. The host is the individual woman, more or less susceptible to stressor‐induced pathology. The environment includes the social and cultural conditions that are ongoing stressors as well as social and cultural modifiers of stress e.g. those factors that may influence how a particular stressor is experienced or what the physical response to it may be. The agent is the immediate emotional or physical stressor requiring her response. We draw from recent literature, published principally since 1990, to illustrate this model.

This epidemiological model posits that whether the individual is overwhelmed by stressors depends not only on the strength of the agents but also upon host susceptibility to stress, as well as the background level of acute, environmental and contextual stressors, and the moderating influence of host, environmental and contextual resources for handling stress. Future research needs to be based on stress hypotheses that include all sides of the triangle, data collection instruments that adequately capture relevant stressors and stress responses, and analytical techniques capable of handling complex, multilevel relationships.
Role of structural birth defects in preterm delivery
Authors: Shaw Gary M. , Savitz David A. , Nelson Verne , Thorp John M.
Published: March 2003

The proportion of preterm births associated with structural birth defects has not been adequately quantified. We explored the proportion of preterm infants with structural birth defects diagnosed in the first year of life, as well as the specific phenotypes of birth defects occurring among preterm infants. The data used were from the California Birth Defects Monitoring Program, a population‐based registry, as well as data from California vital records corresponding to births and fetal deaths in the period 1984–96. The prevalence of structural birth defects exceeded 8% among deliveries with gestational ages 30 weeks, and prevalence decreased to 2% as gestational age increased to 37 weeks gestation. The decreasing prevalence pattern with increasing gestational age was observed for a variety of anatomically defined birth defect groups suggesting that certain birth defects were not the sole contributors to the elevated prevalences among preterm births. Decreasing prevalence with increasing gestational age was also observed across strata of maternal race/ethnicities, ages, infant’s sex and each year studied. These data indicate that structural birth defects may contribute significantly to the proportion of infants who are delivered before 37 weeks gestation.
Seasonality of birth for cancer in Northern England, UK
Authors: Feltbower Richard G. , Pearce Mark S. , Dickinson Heather O. , Parker Louise , McKinney Patricia A.
Published: March 2003

Environmental factors operating around the time of birth may influence the subsequent development of childhood cancer, particularly leukaemia. Certain factors may vary with season (e.g. infections), and we therefore investigated whether there was any evidence of seasonality of month of birth, based on data from 4199 children diagnosed with cancer under the age of 15 years. We extracted details of (i) children born 1960–95 and diagnosed 1968–95 from two population‐based registries, covering the Northern (n = 2053) and Yorkshire (n = 1977) Regional Health Authority and (ii) children born in Cumbria 1950–93 and diagnosed anywhere in the UK before 1994 from a birth cohort database (n = 397). The following diagnostic categories were analysed: 0–14 years ‐ all cancers, leukaemias, acute lymphoblastic leukaemias, central nervous system tumours, all other solid tumours; 1–6 years – leukaemias, acute lymphoblastic leukaemias. Seasonal variation was tested using Walter and Elwood's test, and logistic regression analysis allowing for cyclical variation in month of birth. No evidence of seasonality was present for any group except acute lymphoblastic leukaemia diagnosed among 1‐ to 6‐year‐olds. Seasonal trends varied by region: in the Northern and Cumbrian datasets, seasonality patterns were significant and similar (P < 0.05) with a predicted peak in early spring, whereas in Yorkshire there was less strong evidence of seasonality (P = 0.08) with a peak predicted in late summer. These findings suggest that local seasonal environmental factors operating around the time of birth are not associated with the totality of childhood cancer, but possible links with acute lymphoblastic leukaemia are supportive of a hypothesis of an infectious aetiology.
Birthweight and gestational age effects on motor and social development
Authors: Hediger Mary L. , Overpeck Mary D. , Ruan W. June , Troendle James F.
Published: March 2003

The number of children at risk for delays in motor and social development (MSD) associated with preterm delivery and low birthweight is increasing, but such children are generally not seen as being in need of evaluation. The objective of these analyses was to determine whether there are independent effects of birthweight and gestational age on MSD and the magnitude of effects. Subjects were a representative sample of 4621 US‐born singleton children, aged 2–47 months, examined in the third National Health and Nutrition Examination Survey (1988–94). MSD was assessed using an age‐appropriate scale. Birthweight and gestational age were taken from birth certificates. Mexican–American and ‘other’ race/ethnicity (other than non‐Hispanic white, non‐Hispanic black or Mexican–American), low parental education level, older maternal age, higher birth order, low birthweight (LBW, <2500 g) and preterm delivery (<37 weeks) were all found to be associated with significant (P
< 0.01) delays in MSD. Three per cent of the infants and children were preterm
LBW and 2.2% term LBW (<2500 g, 37–44 weeks). Adjusting for socio‐demographic
factors, preterm LBW children had lower MSD scores (−1.5 ± 0.3 points,
P < 0.0001) through early childhood, as did term LBW children (−0.8
± 0.4 points, P < 0.03). For females, LBW was the most important
perinatal predictor of a lowered score (−0.9 ± 0.3 points compared with
normal birthweight, P < 0.04). For males, scores were additionally decreased
by –0.1 ± 0.03 points/week (P = 0.001) of early delivery. LBW children had less muscle mass, but adjusting for muscularity did not diminish the effects of birth size on MSD. LBW status and preterm delivery are associated independently with small, but measurable, delays in MSD through early childhood and should be considered along with other known risk factors for development delays in determining the need for developmental evaluation.
Prenatal and intrapartum events and sudden infant death syndrome
Authors: Klonoff‐Cohen Hillary S. , P. Indu P. , Edelstein Sharon L.
Published: March 2003

The purpose of this study was to evaluate specific pregnancy and labour and delivery events that may increase the risk of sudden infant death syndrome (SIDS). A matched case–control study was conducted in five counties in southern California, using California death certificate records. The sample consisted of 239 Caucasian, African–American, Hispanic and Asian mothers of SIDS infants and 239 mothers of control infants matched on sex, race, birth hospital and date of birth. Mothers participated in a detailed telephone interview and provided access to obstetric and paediatric records. More case than control mothers reported a family history of anaemia (OR = 2.12, P < 0.001). Placental abruptions were strongly associated with SIDS (unadjusted OR = 7.94, [95% CI 1.34,47.12]). There was an increased risk of SIDS death associated with maternal anaemia during pregnancy (OR = 2.51, [95% CI 1.25,5.03]), while simultaneously adjusting for maternal smoking during pregnancy, maternal years of education and age, parity, infant birthweight, gestational age, medical conditions at birth, infant sleep position and post‐natal smoking. Interactions of anaemia and prenatal smoking as well as anaemia and post‐natal smoking were not statistically significant. There were no other statistically significant differences between case and control mothers for pregnancy conditions, labour and delivery events (e.g. caesarean sections, anaesthesia, forceps) or newborn complications (e.g. nuchal cord, meconium aspiration). Anaemia and placental abruptions were significantly associated with an increased risk of SIDS; both are circumstances in which a fetus may become hypoxic, thereby compromising the subsequent growth, development and ultimate survival of the infant.
Marital status, cohabitation, and the risk of preterm birth in Europe: where births outside marriage are common and uncommon
Authors: Zeitlin Jennifer A. , Saurel‐Cubizolles Marie‐Josèphe , Ancel Pierre‐Yves ,   the EUROPOP Group
Published: March 2003

This article explores whether the impact of marital status on the risk of preterm birth varies in relation to marital practices in the population, defined by the proportion of out‐of‐marriage births. Data come from a case–control study of the determinants of preterm birth in 16 European countries (5456 cases and 8234 controls). There is a significantly elevated risk of preterm birth associated with both cohabitation (OR = 1.29 [1.08, 1.55]) and single motherhood (OR = 1.61 [1.26, 2.07]) for women living in countries where fewer than 20% of births occur outside marriage. In contrast, there is no excess risk associated with marital status when out‐of‐marriage births are more common. This overall result does not apply to all subgroups of preterm births: different patterns emerge for early preterm births and preterm births induced for medical reasons. It is important to consider social context in the analysis of individual risk factors.
Paternal occupational group and risk of offspring with neural tube defects
Authors: Shaw Gary M. , Nelson Verne , Olshan Andrew F.
Published: March 2003

Selected paternal occupations as well as specific occupational exposures to chemicals such as organic solvents have been suggested as possible risk factors for neural tube defects (NTD). We investigated data from a population‐based, case–control study of fetuses and liveborn infants with NTDs among 1989–91 California births and fetal deaths. Interviews were conducted with mothers of 538 NTD cases and 539 non‐ malformed controls. Mothers were asked to report the occupations that the fathers had in the period 3 months before and 3 months after conception. Each job title and industry reported was coded in accordance with the 1990 US Census.

Considering those fathers who worked in managerial and professional occupations as the reference group, elevated odds ratios (OR) for NTDs were observed for the categories: technical, sales and administrative, OR = 1.5 [95% confidence interval 1.0, 2.4]; service, OR = 2.0 [1.2, 3.1]; farming, forestry and fishing, OR = 2.1 [1.3, 3.3]; operators, fabricators and labourers, OR = 1.8 [1.2, 2.7]; and military, OR = 1.9 [0.7, 5.0]. Stratification by NTD phenotype revealed that these elevated ORs were primarily observed for spina bifida phenotypes. Analyses adjusted for maternal body mass index, maternal periconceptional use of multivitamins containing folic acid, paternal race/ethnicity, maternal race/ethnicity and maternal education revealed attenuated risk estimates for most of the occupational groups. Analyses of 182 more specific occupational groups defined by aggregating fathers on similar job titles, when compared with fathers who worked in managerial and professional occupations, revealed that four job title groups were associated with fairly precise effect estimates of ≥1.5. These groups were: cooks; janitors and cleaners; farm workers; and groundsmen/gardeners. Using occupational titles as defined in previous investigations, we did not observe an elevated OR associated with paternal occupational solvent exposures, OR = 0.8 [0.5, 1.3]. These analyses generated potential clues regarding paternal occupational exposures as NTD risk factors. Risk variation observed by spina bifida phenotype is interesting and will need to be investigated further.
Perinatal mortality in Turkey
Authors: Erdem Gulsen
Published: March 2003

A prospective study was conducted to investigate perinatal mortality rate, stillbirth rate and early neonatal mortality rate in 29 centres throughout Turkey between 1 January 1999 and 31 December 1999. The most frequent causes of mortality were determined according to the modified Wigglesworth classification, and the results were evaluated with respect to the differences between the centres and the regions. The total number of births from all centres was 92 587. Perinatal mortality rate was 34.9 per 1000, stillbirth rate 18 and early neonatal death rate 17.2 per 1000. Perinatal mortality rates were highest with 71.9 and 62.9 per 1000 in the regions that have low socio‐economic status and are predominantly rural and semi‐urban. The rate was lowest (27.3 per 1000) in the region that is economically more developed. In 23 out of 29 centres, the causes of death were clearly determined. The most important causes of death according to the modified Wigglesworth classification were antepartum stillbirths (42.7%), prematurity (26.0%) and lethal congenital malformations (13.2%). In conclusion, reduction in the perinatal mortality rate in Turkey is likely to be possible only with the co‐ordination of the government, universities, obstetricians and neonatologists and improvement of prenatal, delivery and postnatal care and prevention of prematurity. Perinatal mortality studies should be extended and better organised regionally in Turkey.
Changes in specific anti‐egg antibody levels following treatment with praziquantel for Schistosoma haematobium infection in children
Authors: MUTAPI  , NDHLOVU  , HAGAN  , WOOLHOUSE
Published: March 2003

Fifty‐seven children 6–15 years old resident in a Schistosoma haematobium endemic area in eastern Zimbabwe were treated with praziquantel at 40 mg/kg body weight. Levels of IgA, IgE, IgG1, IgG2, IgG3, IgG4, and IgM antibodies against soluble egg antigen (SEA) were assayed by ELISA before treatment and at 18 and 36 weeks following treatment. Prevalence of infection (as determined by urine egg counts) was 65% before treatment, all children were confirmed egg negative six weeks after treatment, and re‐infection prevalence was 4% at 18 weeks and 21% at 36 weeks after treatment. At 18 weeks after treatment, there was a massive increase in IgG1 levels and significant increases in IgE and IgG4 levels and significant decreases in IgA and IgG2 levels. Similar patterns occurred at 36 weeks after treatment. Egg positive children showed a more marked increase in IgG1 and (for older children) a more marked decrease in IgG2 levels. There were no other effects of age or sex. IgA and IgG1 levels fell significantly between 18 and 36 weeks following treatment but not to pretreatment levels. The results show that specific anti‐egg antibody responses are highly sensitive to the effects of praziquantel treatment. A possible consequence is that the susceptibility of children to infection with S. haematobium is altered by chemotherapy; this requires further investigation.
Cloning and expression of a cDNA encoding an elongation factor 1β/δ protein from Echinococcus granulosus with immunogenic activity
Authors: Margutti Paola , Ortona Elena , Vaccari Sergio , Barca Stefano , Riganò Rachele , Teggi Antonella , Muhschlegel Fritz , Frosch Matthias , Siracusano Alessandra
Published: March 2003

A cDNA clone (Eg EF‐1β/δ) of Echinococcus granulosus has been isolated by an expression library screened with immunoglobulin (Ig)E of sera from patients with cystic echinococcosis (CE). The Eg EF‐1β/δ was identified on the basis of sequence homology to the subunits β or δ of the elongation factor‐1. The amino acid sequence deduced from this open reading frame is 244 residues long with a predicted molecular mass of 31 kDa. In Southern blot under high stringent condition, Eg EF‐1β/δ hybridized to genomic DNA of E.granulosus at two bands of 4 and 2.5 Kb. In immunoblotting analysis, the Eg EF‐1β/δ protein shows immunological reactivity with sera from CE patients: 51.7% of sera contained IgE, 41.7% IgG and 18.3% IgG4 specific to the recombinant protein. We identify the Eg EF‐1β/δ by immunoblotting with specific monoclonal antibody both in protoscoleces and in sheep hydatid fluid. The higher percentage of humoral immune response against Eg EF‐1β/δ observed in CE patients with calcified cysts than in patients with active cysts indicates the possible release of the protein in the hydatid fluid after protoscoleces degeneration suggesting the possible use of this antigen in the immunosurveillance of CE. Overall, these findings seem to assign to Eg EF‐1β/δ a key role in the allergic disorders and in the complex host–parasite relationship in CE.
Nasal immunization of mice with Cryptosporidium parvum DNA induces systemic and intestinal immune responses
Authors: Sagodira Serge , Iochmann Sophie , Mevelec Marie‐Noelle , Dimier‐Poisson Isabelle , Bout Daniel
Published: March 2003

DNA immunization offers a novel approach to inducing humoral and cellular immunity against infectious pathogens. We examined whether such an approach could be used against cryptosporiodiosis, an intestinal disease caused by the protozoan parasite Cryptosporidium parvum. This infection is a major problem for young ruminants and immunosuppressed individuals in whom cryptosporidiosis causes life‐threatening symptoms. The life cycle of C. parvum takes place in the enterocytes of the intestinal epithelium. We therefore focused our attention on a route of immunization that might induce a mucosal immunoglobulin (Ig)A response. Eight‐week‐old BALB/c mice were immunized intranasally with DNA encoding a 15‐kDa C. parvum sporozoite antigen (CP15‐DNA) cloned onto the plasmid pcDNA3. CP15‐DNA‐immunized mice developed specific and longlasting production of anti‐CP15 Ig A in intestinal secretions and specific IgG in sera 3 months and 1 year after the first DNA inoculation. CP15‐DNA‐immunized mice also developed an antigen‐specific T lymphocyte proliferative response in both spleen and mesenteric lymph nodes. Control mice that received the pcDNA3 plasmid alone did not develop specific humoral and cellular responses. These results indicate that plasmid DNA may provide a powerful means of eliciting intestinal humoral and cellular responses to C. parvum infections in mammals.
Protection in lambs vaccinated with Haemonchus contortus antigens is age related, and correlates with IgE rather than IgG1 antibody
Authors: Kooyman  , Schallig  , Van Leeuwen  , Mackellar  , Huntley  , Cornelissen  , Vervelde
Published: March 2003

Protection by vaccination with excretory–secretory products (ES) from Haemonchus contortus, containing predominantly proteins of 15 and 24 kDa, against an experimental challenge infection depends on the age of the sheep. Vaccinated sheep 9, 6 or 3 months of age were protected for 83%, 77% and −34%, respectively. There was a significant difference in ES‐specific serum IgE response but not in IgG1 response, after the last vaccination between the different age groups. In the protected 9‐month‐old animals, there was an increase up to 18 times the prevaccination levels, while the increase in the unprotected 3‐month‐old animals was at most 1.4 times. The 6‐month‐old animals showed an intermediate increase of approximately six times the prevaccination level. There was no correlation within the 9‐month‐old sheep between ES‐specific IgE levels and protection, measured as worm burden. However, when the different age groups were combined, there was a positive correlation (r = 0.38) between protection and ES‐specific IgE levels 1 week after the vaccination. At the end of the experiment, peripheral blood eosinophils and mast cell counts in abomasal tissue were also significantly higher in the vaccinated and challenged 9‐month‐old sheep than in the vaccinated and challenged 3‐month‐old or than in the 9‐month‐old sheep with challenge, but without vaccination. Increased serum IgE levels, eosinophilia and mucosal mast cell hyperplasia are the hallmarks of a Th2 response and were all demonstrated in protected, older sheep, but not in unprotected, younger sheep.
Helper T cell and antibody responses to infection of CBA mice with Babesia microti
Authors: Chen Dehua , Copeman D. Bruce , Burnell Jim , Hutchinson Gareth W.
Published: March 2003

Helper T cell cytokine and antibody responses were investigated in mice after infection with Babesia microti (King strain). Infection of CBA mice with 106 parasitized erythrocytes resulted in the development of a transitory high parasitaemia which peaked 14 days post infection (DPI), and was resolved at 24 DPI. Th1 responses were activated predominately during the acute phase (6–18 DPI) whereas Th2 responses predominated during the recovery phase (14–28 DPI) as detected by the reverse transcriptase polymerase chain reaction. Increased expression of Th1 cytokines was first detected at 6 DPI (IL‐2) and 8 DPI (IFN‐γ) and their peak levels were reached at 12 DPI. After the peak levels were reached, they progressively declined and fell to baseline levels (22 DPI). Increased expression of Th2 cytokines (IL‐4 and IL‐10) first appeared at 14 DPI, peaked at 20 DPI and Th2 cytokine levels were elevated till the end of the study (28 DPI). Levels of serum IFN‐γ detected by a sandwich ELISA correlated well with IFN‐γ gene expression and were detectable at 8–18 DPI. IgM against B. microti was first detected in serum by ELISA at 4 DPI, and peaked at 10 DPI. The levels of IgM subsequently declined but remained positive at low titre till the end of study. IgG against B. microti was first detected at 8 DPI and peak levels were reached at 24 DPI and remained at that level until the end of study. The results of the present study show that Th1 cytokines predominated in the early inflammatory response and might be involved in control of levels of acute parasitaemia whereas the Th2‐associated responses, including expression of IL‐4 and IL‐10 and the production of parasite‐specific IgG, might be the functional means for the reduction and clearance of the parasite from the body. It was concluded that an effective vaccine against Babesia spp. should be designed to induce Th1 responses to maintain the parasitaemia at unfulminating levels and also maintain Th2 responses to clear the parasite from the body.
Differential ability of specific regions of Plasmodium falciparum sexual‐stage antigen, Pfs230, to induce malaria transmission‐blocking immunity
Authors: Bustamante  , Woodruff  , Oh  , Keister  , Muratova  , Williamson
Published: March 2003

Antibodies raised against an Escherichia coli‐produced recombinant protein encoding a 76‐kDa section (region C) of malaria transmission‐blocking vaccine candidate, Pfs230, have previously been shown to significantly reduce the ability of Plasmodium falciparum parasites to infect mosquitoes (71.2–89.8%). To further define the region of the Pfs230 required for transmission‐blocking activity, four recombinant proteins each encoding a section of region C (Pfs230 amino acids 443–1132) were produced using the same E. coli expression system and tested for immunogenicity in mice: (i) r230/MBP.C5′ encodes the first half of region C (amino acids 443—791, six cysteines); (ii) r230/MBP.CM1 encodes only cysteine motif (CM) 1 (amino acids 583—913, eight cysteines); (iii) r230/MBP.C1.6 (amino acids 453–913, eight cysteines) also includes all of CM1; and (iv) r230/MBP.C2 encodes only CM2 (amino acids 914–1268, 11 cysteines). All the recombinant proteins induced antibodies that recognized parasite‐produced Pfs230, but the titre of the Pfs230 specific‐antibodies generated varied, C = C1.6 = C5′ > CM1 > CM2. Two recombinants, r230/MBP.C5′ and r230/MBP.C1.6, induced antibody titres that were equivalent to or greater than the titre generated by r230/MBP.C. However, in contrast to r230/MBP.C, none of the recombinants induced antibodies that effectively blocked parasite infectivity to mosquitoes. This suggests that the inclusion of amino acids 914–1132 is important for the production of the transmission‐blocking epitope present in region C.
Immunopathology of intestinal helminth infection
Authors: Garside Paul , Kennedy Malcolm W. , Wakelin Derek , Lawrence Catherine E.
Published: March 2003

The relationship between intestinal pathology and immune expulsion of gastrointestinal nematodes remains controversial. Parasite expulsion is associated with intestinal pathology in several model systems and both of these phenomena are T cell dependent. However, while immune expulsion of gastrointestinal helminth parasites is usually associated with Th2 responses, the effector mechanisms directly responsible for parasite loss have not been elucidated. In contrast, the intestinal pathology observed in many other disease models closely resembles that seen in helminth infections, but has been attributed to Th1 cytokines. We have used infection with the nematode Trichinella spiralis in mice defective for cytokines to demonstrate that although parasite expulsion is indeed IL‐4 dependent, contrary to expectations, the enteropathy is also regulated by IL‐4. Furthermore, abrogation of severe pathology in iNOS deficient and TNF receptor defective animals does not prevent parasite expulsion. TNF and iNOS are therefore involved in intestinal pathology in nematode infections, apparently under regulation by IL‐4 and Th2 mediated responses. Therefore, it appears that the IL‐4‐dependent protective response against the parasite operates by a mechanism other than merely the gross degradation of the parasite's environment brought about by the immune enteropathy. However, it remains important to elucidate the protective mechanisms involved in parasite expulsion, which are still unclear.
Alterations of intralesional and lymph node gene expression and cellular composition induced by IL‐12 administration during leishmaniasis
Authors: Schopf Lisa R. , Erickson Jamie , Hayes Lori , Chung Charles , Lavigne Liz , Sypek Joseph
Published: March 2003

Changes in gene expression and cellular distribution in the lymph node and at the site of infection, the footpad, during Leishmania major infection and/or IL‐12 administration were evaluated. Otherwise susceptible BALB/c mice given IL‐12 are able to resolve infection. Interestingly, iNOS was not induced in the lymph node by IL‐12, yet, nitric oxide is critical in the control of leishmaniasis. However, we observed an increase in iNOS at the lesion site in response to IL‐12. These results reflect the importance of examining the primary site of infection. We observed no changes in inflammation at the lesion site; however, IL‐12 promoted an early inflammatory response in the lymph nodes. IL‐12 administration differentially affected both the local and systemic immune response to invading leishmanial parasites. IL‐12 induced iNOS at the lesion site and an early granulomatous inflammation in the lymph node; therefore, we hypothesize that these are key events responsible for the resolution of disease in BALB/c mice treated with IL‐12.
Regulation of the immune response in lymphatic filariasis: perspectives on acute and chronic infection with Wuchereria bancrofti in South India
Authors: Nutman Thomas B. , Kumaraswami V.
Published: March 2003

Delineating the immune responses in lymphatic filariasis has been complicated not only by the rapidly expanding knowledge of new immunological mediators and effortors, but also by new methodologies (in particular, circulating filarial antigen detection) for defining and categorizing filarial‐infected individuals. By using assays for circulating antigen in the sera collected as part of the many immunological studies performed on individuals in a Wuchereria bancrofti‐endemic region of South India, we have attempted to explore the influence of patency on the antigen‐driven proliferative and cytokine responses seen in peripheral blood mononuclear cells of individuals with varying clinical manifestations of lymphatic filarial infection. Moreover, we have provided perspectives on the differences between acute and chronic infection with W. bancrofti and suggested mechanisms that may underly the modulation of the immune response as patency occurs.
Mouse splenic CD4+ and CD8+ T cells undergo extensive apoptosis during a Plasmodium chabaudi chabaudi AS infection
Authors: Sanchez‐Torres Luvia , Rodriguez‐Ropon Andrea , Aguilar‐Medina Maribel , Favila‐Castillo Luis
Published: March 2003

The presence and phenotype of apoptotic lymphocytes was studied in spleen cell suspensions taken from CB6F1 mice infected with Plasmodium chabaudi chabaudi AS. High levels of apoptotic cells were found, associated with high parasitaemias and splenomegaly. This was also accompanied by expansion and disarray of spleen white pulp. Apoptosis levels lowered when parasitaemia was cleared, but were still higher than in normal mice. At this time, the spleen was diminishing in size and the white pulp was contracting and rearranging. When parasitaemia was patent, the cells most affected by apoptosis were CD4+ T cells followed by CD8+ T cells, and to a lesser extent B220+ B cells. When parasitaemia was cleared, CD8+ T cells and B220+ B cells returned to basal levels of apoptosis, while CD4+ T cells still had higher apoptosis levels than normal mice. A similar pattern of lymphocyte subpopulation apoptosis was found in infected BALB/c mice, despite the fact that, for this mouse model, it has been reported that B cells are the cells that are most affected by apoptosis. We consider that the high levels of apoptosis in CD4+ T cells when parasitaemias are still high are not easily explained by a normal mechanism of down regulation of the immune response.
Assessment of in vivo complement activation on the Echinococcus granulosus hydatid cyst wall
Authors: Ferreira Ana Maria , Diaz Alvaro , Fernandez Cecilia , Sim Robert B.
Published: March 2003

The larval stage of the parasite Echinococcus granulosus causes hydatid disease. The hydatid cyst is potentially capable of activating host complement, since it is a large, persistent, carbohydrate‐rich structure, coated with host immunoglobulins, and localized in the host's internal organs. Nonetheless, in vitro studies have suggested that the cyst surface, the hydatid cyst wall (HCW), is a poor complement activator. In this study, we assessed the occurrence of in vivo complement activation on the hydatid cyst by measuring the levels of two complement activation products, C3d and complexes bearing a C9 activation neoepitope (TCC/MAC), in extracts from HCW of human origin. Low amounts of C3d and TCC/MAC were found in HCW in comparison with their levels in normal human plasma and activated human sera, suggesting that in vivo complement activation on HCW is efficiently down‐regulated. This regulation may contribute to limit host inflammation which has been observed to correlate with parasite degeneration and death.
Identification of HLA‐A2 restricted CD8+ T‐lymphocyte responses to Plasmodium vivax circumsporozoite protein in individuals naturally exposed to malaria
Authors: Arévalo‐Herrera Myriam , Valencia Anais Zully , Vergara Juana , Bonelo Anilza , Fleischhauer Katharina , González John Mario , Restrepo Juan Carlos , López José Alejandro , Valmori Danila , Corradin Giampietro , Herrera Sócrates
Published: March 2003

Specific CD8− T‐lymphocyte (CTL) activity against Plasmodium pre‐erythrocytic stages (P‐ES) derived antigens is considered one of the most important mechanisms for malaria protection. Plasmodium vivax is the second most prevalent human malaria parasite species distributed worldwide. Although several CTL epitopes have been identified in Plasmodium falciparum P‐ES derived antigens, none has been described for P. vivax to date. In this study, we analysed HLA‐A*0201 specific CD8− T‐lymphocyte responses to the P. vivax circumsporozoite (CS) protein in both malaria exposed and non‐exposed populations from the Colombian Pacific Coast. First, we analysed the prevalence of HLA‐A2 allele in the study populations and found that approximately 38% of the individuals expressed this molecule and that 50% of them were HLA‐A*0201. We then selected, on the P. vivax CS, five peptide sequences containing the HLA‐A*0201 binding motifs and used the corresponding synthetic peptides to evaluate the CD8− T‐lymphocyte interferon (IFN)‐γ response. Peripheral blood mononuclear cells from the HLA‐A*0201 donors were in vitro stimulated with these peptides and IFN‐γ production was determined by an ELISPOT assay. Specific CD8− T‐lymphocyte responses were detected for three peptides located in the C‐terminal region of the protein. Specific responses to these peptides were also detected in several individuals expressing different HLA‐A*02 subtypes. The potential of these peptides to induce specific cytolysis and that of long synthetic peptides comprising these epitopes as P. vivax malaria vaccine subunits are being studied.