bluuebunny/crossref_metadata_2025 huggingface dataset:
Ubiquitin‐only intraneuronal inclusion in the substantia nigra is a characteristic feature of motor neurone disease with dementia
Authors: Al‐Sarraj S. , Maekawa S. , Kibble M. , Everall I. , Leigh N.
Published: March 2003

Two types of ubiquitinated inclusions have been described in motor neurone disease (MND). (1) Skein or globular ubiquitinated inclusions in the motor neurones (more frequently in the lower motor neurones). This is a characteristic feature of all motor neurone disease categories. (2) Dot‐shape or crescentric ubiquitinated inclusions in the upper layers of cortex and dentate gyrus described in cases of motor neurone disease with dementia (DMND). We investigated the substantia nigra (SN) in MND cases; two cases of motor neurone disease inclusion body (MND‐IB) dementia, six cases of DMND, 14 cases of MND (including one case from Guam and two cases of familial SOD1 mutation), four cases of Parkinson's disease (PD), and 10 cases of age‐matched normal controls. SN and spinal cord sections were stained with ubiquitin (α‐synuclein, tau, PGM1, SMI‐31 and SOD1 antibodies). The neuronal density in SN was quantified by using a computer‐based image analysis system. Four out of six DMND cases showed rounded ubiquitin positive inclusions with irregular frayed edges, associated with neuronal loss, reactive astrocytosis and a large number of activated microglia cells. These inclusions are negative with antibodies to (α‐synuclein, tau, SMI‐31 and SOD1). The SN in cases from MND‐IB dementia and MND showed occasional neuronal loss and no inclusions. The ubiquitin‐only inclusions in SN of DMND cases are similar (but not identical) to the ubiquitinated inclusions described previously in the spinal cord of MND cases and are distinct from Lewy bodies (LBs). The degeneration of SN is most likely a primary neurodegenerative process of motor neurone disease type frequently involving the DMND cases. MND disease is a spectrum and multisystem disorder with DMND located at the extreme end of a spectrum affecting the CNS more widely than just the motor system.
Expression of hypoxia‐inducible factor 1α in tumours of patients with glioblastoma
Authors: Søndergaard K. L. , Hilton D. A. , Penney M. , Ollerenshaw M. , Demaine A. G.
Published: March 2003

Angiogenesis is a prominent feature of glioblastomas but the mechanisms involved in the control of this process are poorly understood. We have investigated the potential role of a recently described transcription factor, hypoxia‐inducible factor 1 (HIF‐1), which initiates the transcription of a number of hypoxia‐inducible genes, including those encoding vascular endothelial growth factor and its receptors. HIF‐1 protein expression was assessed by immunocytochemistry, using a monoclonal antibody to the α subunit (HIF‐1α). HIF‐1 mRNA expression was assessed by reverse transcriptase‐polymerase chain reaction (RT‐PCR) and the ribonuclease protection assay (RPA). Strong nuclear expression of HIF‐1α protein was seen in the majority of glioblastomas and anaplastic astrocytomas, particularly surrounding areas of necrosis in glioblastomas. In the majority of these tumours upregulation of HIF‐1α mRNA was also demonstrated, with a significant increase in glioblastomas compared to lower grade tumours. No correlation was found between the presence of HIF‐1α protein and immunohistochemical expression of p53 protein. These findings are in keeping with an important role of HIF‐1α in the vascularization of glioblastomas and suggest that upregulation is at least partly at a transcriptional level.
Trans‐sarcolemmal proteins situated central to the subsarcolemmal region
Authors: Borchert A. , Goebel H. H.
Published: March 2003

Trans‐sarcolemmal proteins located inside, within, and outside of the muscle fibre plasma membrane fall into two categories, the dystrophin‐glycoprotein complex (DGC) and non‐DGC‐related proteins, e.g. dysferlin, caveolin, dystrobrevins and syntrophins. Mutational defects are responsible for their immunohistochemical absence or reduction giving rise to certain muscular dystrophies. In other neuromuscular disorders, i.e. inflammatory, metabolic, and neurogenic processes, transarcolemmal proteins are well preserved. Unlike desmin and plectin, which form a honeycomb‐type network across the muscle fibre and a subsarcolemmal layer, trans‐sarcolemmal proteins are not expressed central to the subsarcolemmal region in normal mature muscle fibres. In three different types of lesion, transarcolemmal proteins may be encountered within muscle fibres unrelated to the subsarcolemmal region: (1) immature fibres: dysferlin and caveolin different from the absence of DGC proteins in regenerating muscle fibres and, thereby, underscoring their different transcellular trafficking; (2) lining autophagic vacuoles and pseudo‐vacuoles identified by invagination of the sarcolemma; (3) accruing within core‐like lesions marked by sarcomeric disintegration and in association with the accumulation of other proteins, e.g. desmin, α‐B crystallin. Our differential diagnostic studies indicate that different trans‐sarcolemmal proteins are encountered central to the subsarcolemmal region in different myopathological conditions and therefore for different pathogenetic reasons.

Acknowledgements:  These studies have been supported by the Deutsche Gesellschaft für Muskelkranke e.V., Freiburg/Germany, the European Neuromuscular Centre (ENM), Baarn/The Netherlands, and the ‘MAIFOR’ programme of the Johannes Gutenberg University, Mainz/Germany.
Frequent ear infections in association with child‐care characteristics, based on the 1988 Child Health Supplement to the National Health Interview Survey
Authors: Hildesheim  , Hoffman  , Overpeck
Published: March 2003

Using the 1988 Child Health Supplement to the National Health Interview Survey, we analysed the association between child‐care characteristics and frequent ear infections among children under 6 years attending child care. We observed strong associations for 1‐ to 2‐year‐old children for variables involving exposure to many different children, including number of children in the main setting and one or more changes in child‐care arrangement in the past year. No significant effects were observed for the children under 1 year, but sample sizes were small. Likewise, no strong associations were observed for the 3‐ to 5‐year‐old children, but they may have outgrown the detrimental effects of repeated respiratory tract infections.
A population‐based cohort study of the relation between maternal birthweight and risk of gestational diabetes mellitus in four racial/ethnic groups
Authors: Williams  , Emanuel  , Kimpo  , Leisenring  , Hale
Published: March 2003

Intrauterine growth retardation and low birthweight have been associated with an increased risk of insulin resistance and type II diabetes later in life. We hypothesised that maternal low birthweight is associated with an increased risk of gestational diabetes mellitus (GDM). Study subjects comprised women giving birth in Washington State between 1987 and 1995. Information for 21 528 births to non‐Hispanic white women, 6359 to African‐American women, 7456 to Native American women and 6496 to Hispanic women was available for analysis. All information was derived from statewide computerised vital records and hospital discharge summaries of obstetric and neonatal admissions with linkage to birth certificates of mothers. Maternal birthweight was collected from subjects’ birth certificates. Information from both the birth certificates and the obstetric and neonatal admissions database was used to determine whether subjects developed GDM. Poisson regression models were estimated to calculate unadjusted and adjusted risk ratios (RRs) and 95% confidence intervals (CIs) for GDM by categories of maternal birthweight. The cumulative incidence of GDM among non‐Hispanic white, African‐American, Native American and Hispanic women was 2.8, 2.6, 2.7 and 3.0% respectively. After adjusting for maternal age, parity, cigarette smoking, history of chronic hypertension and participation in the Medicaid programme, non‐Hispanic white women with a birthweight < 2000 g were 1.7 times more likely to have had their pregnancy complicated by GDM (RR = 1.7; 95% CI 0.8, 3.3) than those with a birthweight 3000–3999 g. The corresponding adjusted RRs for African‐American, Native American, and Hispanic women were 2.8 [95% CI 1.2, 6.1], 3.1 [95% CI 1.2, 8.2] and 2.4 [95% CI 0.9, 6.0] respectively. Among African‐American women, those with a birthweight 4000 g also experienced a twofold increased risk of GDM (RR = 2.1; 95% CI 1.0, 4.1). This association of high birthweight and increased GDM risk was not found among women in the other three racial/ethnic groups. These findings suggest that individuals with low birthweight constitute a group at increased risk for GDM.
Socio‐economic disparities in pregnancy outcome: why do the poor fare so poorly?
Authors: Kramer M.S. , Séguin L. , Lydon J. , Goulet L.
Published: March 2003

In this paper, we review the evidence bearing on socio‐economic disparities in pregnancy outcome, focusing on aetiological factors mediating the disparities in intrauterine growth restriction (IUGR) and preterm birth. We first summarise what is known about the attributable determinants of IUGR and preterm birth, emphasising their quantitative contributions (aetiological fractions) from a public health perspective. We then review studies relating these determinants to socio‐economic status and, combined with the evidence about their aetiological fractions, reach some tentative conclusions about their roles as mediators of the socio‐economic disparities. Cigarette smoking during pregnancy appears to be the most important mediating factor for IUGR, with low gestational weight gain and short stature also playing substantial roles. For preterm birth, socio‐economic gradients in bacterial vaginosis and cigarette smoking appear to explain some of the socio‐economic disparities; psychosocial factors may prove even more important, but their aetiological links with preterm birth require further clarification. Research that identifies and quantifies the causal pathways and mechanisms whereby social disadvantage leads to higher risks of IUGR and preterm birth may eventually help to reduce current disparities and improve pregnancy outcome across the entire socio‐economic spectrum.
Molecular epidemiology of preterm delivery: methodology and challenges
Authors: Wang Xiaobin , Zuckerman Barry , Kaufman Gary , Wise Paul , Hill Maria , Niu Tianhua , Ryan Louise , Wu Di , Xu Xiping
Published: March 2003

Preterm delivery (PTD) appears to be a complex trait determined by both genetic and environmental factors. Few studies have examined genetic influence on PTD. The overall goal of our study is to examine major candidate genes of PTD and to test gene–environment interactions. Our study includes 500 preterm trios, including 500 preterm babies and their parents and 500 maternal age‐matched term controls. We will perform the transmission/disequilibrium test (TDT) on candidate genes thought to be important in each of the four biological pathways of PTD: (1) decidual chorioamionotic inflammation: interleukin 1 (IL‐1), IL‐6, and tumour necrosis factor (TNF); (2) maternal and fetal stress: corticotropin‐releasing hormone (CRH); (3) uteroplacental vascular lesions: methylenetereahydrofolate reductase (MTHFR); and (4) susceptibility to environmental toxins: GSTM1, GSTT1, CYP1A1, CYP2D6, CYP2E1, NAT2, NQO1, ALDH2, and EPHX. We will also perform standard case‐control analyses on the 500 preterm cases and 500 term controls to examine gene–environment interactions. The major environmental, nutritional and social factors as well as clinical variables known or suspected to be associated with PTD will be used to test for gene–environment interactions. This study integrates epidemiological and clinical data as well as genetic markers along major pathogenic pathways of PTD. The findings from this study should improve our understanding of genetic influences on PTD and gene–environment interactions.
Preterm birth, stillbirth and infant mortality among triplet births in Canada, 1985–96
Authors: Joseph K. S. , Marcoux Sylvie , Ohlsson Arne , Kramer Michael S. , Allen Alexander C. , Liu Shiliang , Wen Shi Wu , Demissie Kitaw , Sauve Reg , Liston Robert ,   for the Fetal Infant Health Study Group of the Canadian Perinatal Surveillance System
Published: March 2003

Recent increases in the frequency of multiple births and simultaneous increases in preterm birth among multiple births have focused attention on such births. However, most previous studies have examined twins rather than higher‐order multiples. We carried out a study to examine rates and trends in preterm birth and in gestational age‐specific fetal and infant mortality among triplet births in Canada. We used data from the stillbirth, live birth and mortality files of Statistics Canada for the years 1985–97. All births in Canada (excluding those occurring in Ontario and Newfoundland) were included in the study, with two periods (1985–90 vs. 1991–96) being contrasted for assessing temporal change. Changes were estimated using relative risks, 95% confidence intervals [CI] and two‐tailed P‐values. The rate of preterm birth among triplet live births increased by 6% (95% CI 3%, 9%) from 90.4% in 1985–90 to 96.0% in 1991–96. Stillbirth rates among triplets did not change significantly and were 30.3 per 1000 total births in 1985–90 and 33.8 per 1000 total births in 1991–96. Infant mortality among triplets declined from 112.7 per 1000 live births in 1985–90 to 73.8 per 1000 live births in 1991–96. In spite of temporal reductions in infant mortality, triplet births continue to be associated with very high rates of preterm birth and fetal and infant mortality. Fetal mortality among triplets has not changed over the last ten years.
The effect of anti‐IL‐10 on proliferation and cytokine production in human schistosomiasis: fresh versus cryopreserved cells
Authors: GROGAN JANE L. , KREMSNER PETER G. , DEELDER ANDRE M. , YAZDANBAKHSH MARIA
Published: March 2003

In this study we neutralized endogenous IL‐10 in PBMC from individuals chronically infected with Schistosoma haematobium by using anti‐IL‐10 MoAbs, and examined the effect and adult worm antigen (AWA)‐specific responses in both fresh or cryopreserved cells. Anti‐IL‐10 alone increased background proliferation of PBMC, but did not augment the AWA‐specific responses in either fresh or frozen cells. In freshly isolated PBMC, IFN‐γ production in response to AWA was enhanced significantly in the presence of anti‐IL‐10. In cryopreserved cells, the augmentation of IFN‐γ in the presence of anti‐IL‐10 was four‐fold less than in the freshly‐isolated cells. Neutralization of IL‐10 had no effect on IL‐4 production. These data show that IL‐10 plays a role in specifically down‐regulating Th1‐ but not Th2‐type responses and, in contrast to previous reports, anti‐IL‐10 does not augment proliferation to parasite antigen in chronic schistosomiasis.
Mosquito feeding modulates Th1 and Th2 cytokines in flavivirus susceptible mice: an effect mimicked by injection of sialokinins, but not demonstrated in flavivirus resistant mice
Authors: ZEIDNER NORDIN S. , HIGGS STEPHEN , HAPP CHRISTINE M. , BEATY BARRY J. , MILLER BARRY R.
Published: March 2003

Culex pipiens and Aedes aegypti mosquitoes were fed on C3H/HeJ mice and systemic cytokine production was quantified from stimulated lymphocytes harvested four to ten days after feeding. Mosquito feeding on C3H/HeJ mice significantly down regulated IFNγ production seven to ten days post feeding by Cx. pipiens and seven days after Ae aegypti feeding. Th2 cytokines, IL‐4 and IL‐10, were significantly up regulated 4–7 days after Cx. pipiens and Ae. aegypti feeding. The immunosuppressive effect of Cx. pipiens feeding on systemic cytokine production was not evident in congenic flavivirus resistant (C3H/RV) mice, as systemic IFNγ and IL‐2 were significantly up regulated at days 7 and 10, correlating with a significant decrease in IL‐4 10 days after feeding by Cx. pipiens mosquitoes. Inoculation of 5–1000 ng of sialokinin‐I into C3H/HeJ mice mimicked the effect of Ae. aegypti feeding by down regulating Th1 cytokines and significantly up regulating Th2 cytokines four days post inoculation. Injections of sialokinin‐II resulted in only moderate effects on IFNγ and IL‐4 production seven and ten days after injection. Thus natural feeding by two arbovirus vectors had a profound T cell modulatory effect in vivo in virus susceptible animals which was not demonstrated in the flavivirus resistant host. Moreover, sialokinin‐I and sialokinin‐II mimicked the effect of mosquito feeding by modulating the host T cell response. These results may lend new insight into specific aspects of the role of the mosquito vector in potentiating virus transmission in the mammalian host.
Egg‐hatching inhibition in mice immunized with recombinant Schistosoma bovis 28 kDa glutathione S‐transferase
Authors: VIANA DA COSTA ALEXANDRA , GAUBERT SOPHIE , LAFITTE SOPHIA , FONTAINE JOSETTE , CAPRON ANDRÉ , GRZYCH JEAN‐MARIE
Published: March 2003

The capacity of a recombinant glutathione S‐transferase from Schistosoma bovis (rSb 28GST) to protect BALB/c mice against homologous and heterologous infections with, respectively, S. bovis or Schistosoma mansoni has been studied. Two injections of the rSb 28GST and an intravenous boost resulted in a marked specific IgG response on the day of experimental challenge with S. bovis or S. mansoni cercariae. Immunization of BALB/c mice led to a reduction in egg maturation and egg viability after infection with S. bovis or S. mansoni. Adult worm recoveries after an S. bovis challenge infection and tissue egg densities (intestine and liver) in S. mansoni challenge infection were also reduced in the immunized groups, but these differences were not statistically significant. No association between in vitro inhibition of GST enzymatic activity induced by immunized mouse sera and worm burden reduction was recorded. The analysis of the immune response, on the day of perfusion, showed the production of immunoglobulin (Ig)G1, IgG2a and IgG2b specific antibodies and the production of interleukin (IL)‐4 and IL‐5 by spleen cells after rSb 28GST stimulation. These data suggest that rSb 28GST immunization induces a moderate effect upon egg maturation and egg hatching, suggesting the involvement of similar mechanisms of action and common, but not exclusive, targets during S. bovis and S. mansoni infections. As a consequence, immunization with rSb 28GST may prove useful in affecting the pathology and transmission of African schistosomes.
Adversarial relationship between the Leishmania lipophosphoglycan and protein kinase C of host macrophages
Authors: Turco Salvatore J.
Published: March 2003

The dominant glycoconjugate on the cell surface of all Leishmania promastigotes is an unusual glycoconjugate named lipophosphoglycan (LPG). Its relative abundance, unique structure, and cellular location have implicated LPG as an essential virulence determinant. One feature of LPG resides in its strong inhibitory effect on the activity of protein kinase C (PKC) of host macrophages. This article summarizes the evidence that LPG is inhibitory toward PKC activation in macrophages and discusses the implication of such inhibition on intramacrophage survival of the parasite.
Vaccination of Manchego lambs against Haemonchus contortus with a somatic fraction (p26/23) of adult parasites
Authors: Domínguez‐Toraño Inés A. , Cuquerella Montserrat , Gómez‐Muñoz Mª.teresa , Méndez Susana , J.fernández‐Pérez Francisco , M.alunda José
Published: March 2003

A low molecular weight fraction from adult Haemonchus contortus containing two peptides (p26/23) was used to vaccinate Manchego female lambs between 3.5 and 5 months of age. Immunizing injections were given three times on days 0, 14 and 28 of the experiment. On day 43, lambs were challenged with 400 third stage larvae/kg live weight. Vaccination induced a lengthening of prepatent periods, significant reduction (> 60%) in mean faecal egg counts and smaller variations in packed cell volume values. At necropsy, average worm burden in the vaccinated lambs was significantly lower (61.6%) than that found in unvaccinated challenged animals. A clear correlation was found between protection and serum antibody response in immunized lambs.
Stat6 dependent goblet cell hyperplasia during intestinal nematode infection
Authors: Khan W.I. , Blennerhasset P. , Ma C. , Matthaei K.I. , Collins S.M.
Published: March 2003

To identify the role of signal transducer and activator of transcription factor 6 (Stat6) in the development of intestinal goblet cell hyperplasia during nematode infection, we compared the number of goblet cells in Stat6 deficient (Stat6 −/−) mice with that generated in wild‐type (Stat6 +/+) mice in Trichinella spiralis infection. The number of goblet cells significantly increased with infection in wild‐type mice. However, Stat6 −/− failed to generate infection‐induced goblet cell hyperplasia and a significantly lower number of goblet cells was observed in Stat6 −/− mice on days 14 and 21 postinfection compared to Stat6 +/+ mice. In addition to suppressed goblet cell numbers, Stat6 −/− mice exhibited severe impairment in their ability to produce IL‐4 and IL‐13 and to expel the parasites from the gut. Our study clearly shows an essential role of Stat6 in intestinal goblet cell hyperplasia which accompanies this infection. We postulate that Th2 cytokines regulate the development of goblet cell hyperplasia in gut during nematode infection via Stat6 activation and that the increased number of goblet cells plays an important role in host protective immunity against the infection.
Dendritic cells pulsed with unfractionated helminthic proteins to generate antiparasitic cytotoxic T lymphocyte
Authors: Jenne Lars , Arrighi Jean‐Francois , Sauter Birthe , Kern Peter
Published: March 2003

Dendritic cells (DC) are sentinels of immunity. We determined their role in the induction of immunity against alveolar echinococcosis, caused by the larval stage of the cestode Echinococcus multilocularis. Furthermore, we evaluated if unfractionated protein from E. multilocularis (Em‐Ag) can be used as loading agent for DC (comparable to unfractionated tumour proteins) in order to generate antiparasitic cytotoxic T lymphocyte (CTL). Interestingly, immature DC did not mature in the presence of 1 µg/ml Em‐Ag as analysed by FACS and mixed leucocyte reactions. Yet, their capacity to take up dextran was markedly reduced. Further maturation of immature Em‐Ag pulsed DC could be induced by proinflammatory cytokines. These mature DC were slightly better inducers of T cell proliferation when compared with unpulsed mature DC. Importantly, by repetetive stimulation of autologous CD8+ lymphocytes with the Em‐Ag pulsed mature DC, we were able to generate specifically proliferating CTL lines. Thus, immunotherapy with ex vivo generated Em‐Ag pulsed DC might be of benefit for patients inheriting this incurable disease.
CD1d‐restricted NK T cells are dispensable for specific antibody responses and protective immunity against liver stage malaria infection in mice
Authors: Romero Jackeline F. , Eberl Gérard , Robson Macdonald H. , Corradin Giampietro
Published: March 2003

Immunization with a single dose of irradiated sporozoites is sufficient to induce protection against malaria in wild‐type mice. Although this protection is classically attributed to conventional CD4+ and CD8+ T cells, several recent reports have suggested an important role for CD1‐restricted NK T cells in immunity to malaria. In this study, we directly compared the ability of C57BL/6 wild‐type and CD1‐deficient mice to mount a protective immune response against Plasmodium berghei sporozoites. Our data indicate that CD1‐restricted NK T cells are not required for protection in this model system. Moreover, specific IgG antibody responses to the P. berghei circumsporozoite repeat sequence were also unaffected by CD1 deficiency. Collectively, our data demonstrate that CD1‐restricted NK T cells are dispensable for protective immunity to liver stage P. berghei infection.
Age‐related protective immunity after vaccination with Haemonchus contortus excretory/secretory proteins
Authors: Vervelde L. , Kooyman F.N.J. , Van Leeuwen M.A.W. , Schallig H.D.F.H. , Mackellar A. , Huntley J.F. , Cornelissen A.W.C.A.
Published: March 2003

Protection against an experimental challenge infection by immunization with excretory/secretory products (ES) from Haemonchus contortus, containing predominantly proteins of 15 and 24 kDa, depends on the age of the sheep. Vaccinated sheep 9 and 6 months of age had reduced final worm burdens of 82 and 77, respectively. No reduction in worm burden was found in 3‐month‐old lambs. Nine‐month‐old sheep had significantly higher ES‐specific serum immunoglobulin (Ig)G1 and IgA during immunizations and after challenge infection than 3‐month‐old lambs. There was no correlation within the 9‐month‐old sheep between ES‐specific IgA or IgG1 levels and protection, measured as worm burden. However, when the different age groups were combined, negative correlations between percentage protection and ES‐specific IgA and IgG1 levels after challenge were found. 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. The responses measured in young lambs were similar to the responses in sheep, but the height of these responses was in general of a lower magnitude.
Wolbachiabacteria in filarial immunity and disease
Authors: Taylor Mark J. , Cross Helen F. , Ford Louise , Makunde Williams H. , Prasad G.B.K.S. , Bilo Katja
Published: March 2003

Lymphatic filarial nematodes are infected with endosymbiotic Wolbachia bacteria. Lipopolysaccharide from these bacteria is the major activator of innate inflammatory responses induced directly by the parasite. Here, we propose a mechanism by which Wolbachia initiates acute inflammatory responses associated with death of parasites, leading to acute filarial lymphangitis and adverse reactions to antifilarial chemotherapy. We also speculate that repeated exposure to acute inflammatory responses and the chronic release of bacteria, results in damage to infected lymphatics and desensitization of the innate immune system. These events will result in an increased susceptibility to opportunistic infections, which cause acute dermatolymphangitis associated with lymphoedema and elephantiasis. The recognition of the contribution of endosymbiotic bacteria to filarial disease could be exploited for clinical intervention by the targeting of bacteria with antibiotics in an attempt to reduce the development of filarial pathology.
Susceptibility of tumour necrosis factor‐α genetically deficient mice to Trypanosoma congolense infection
Authors: Iraqi Fuad , Sekikawa Kenji , Rowlands John , Teale Alan
Published: March 2003

The TNF‐α gene on mouse chromosome MMU17 is among the candidates for the trypanosomosis resistance QTL Tir1. Tir1 has the largest effect of those loci so far detected which influence degree of resistance to murine trypanosomosis caused by Trypanosoma congolense infection. We therefore studied the survival to 180 days after challenge with T. congolense of mice that were homozygous and hemizygous with respect to a disruption of the TNF‐α gene on a > 99% C57BL/6 (resistant) background. We also examined the responses of TNF‐α hemizygous mice produced by crossing the deletion line with mice of the C57BL/6J strain, and with mice of the susceptible A/J strain. Mice lacking a functional TNF‐α gene were shown to be highly susceptible to challenge with T. congolense with a median survival time of 37 days. This was comparable to 71 days for control wild‐type mice, and 61 and 111 days for mice of the susceptible A/J and resistant C57BL/6J strains, respectively. In mice of the deletion line, the C57BL/6 TNF‐α allele tended to be dominant to the TNF knockout in terms of resistance. We conclude that TNF‐α plays an important role in resistance to the effects of T. congolense infection in mice.
Recognition of synthetic polypeptides corresponding to the N‐ and C‐terminal fragments of Plasmodium falciparum Exp‐1 by T‐cells and plasma from human donors from African endemic areas
Authors: Meraldi Valentin , Nebié Issa , Moret Rémy , Cuzin‐Ouattara Nadine , Thiocone Ali , Doumbo Ogobara , Esposito Fulvio , Traoré Alfred S. , Corradin Giampietro , Terenzi Silvia
Published: March 2003

The present work describes the recognition of three synthetic polypeptides encompassing the N‐ and C‐terminal regions of the transmembrane Exp‐1 protein of the parasite Plasmodium falciparum by plasma and peripheral blood mononuclear cells from naturally exposed individuals living in African endemic areas. The three polypeptides comprise the sequences 23–105, 73–162 and 101–162, and overlap at the transmembrane domain (73–105). Thus, they permitted characterization of the immune response specific to the N‐ and C‐terminal domains in an independent fashion. Two different populations were evaluated, one in the village of Safo in Mali and the other in the villages of Somnaway, Kabortenga and Toussouktenga in Burkina Faso. Antibodies to the sequence 73–162 of Pf Exp‐1 were found in 70% of adult Mali donors and in all of the donors tested from Burkina Faso. Strikingly, the N‐terminal fragment Pf Exp‐1 23–105 was only weakly recognized by a few donors. Evaluation of the T‐cell response indicated that the peptide Pf Exp‐1 23–105 was more potent than Pf Exp‐1 73–162 in inducing a proliferative response. A correlation between peptide‐specific interferon‐γ and interleukin‐6 production and proliferation to peptide Pf Exp‐1 23–105 was observed. Further studies are needed to evaluate this molecule as a vaccine candidate.
Decreased immune response as a proximate cost of copulation and oviposition in a damselfly
Authors: SIVA‐JOTHY MICHAEL T. , TSUBAKI YOSHITAKA , HOOPER ROWAN E.
Published: March 2003

Abstract.Males and females of the Japanese calopterygid damselfly, Matrona basilaris japonica Fester, showed a rapid (within 24 h), and significant reduction in immune system function (encapsulation response) after reproductive activity (copulation or oviposition).

 A similar, but non‐significant, change occurred in males that conducted energetically costly behaviour (fighting).

 These data suggest that there may be physiological costs other than energy‐based trade‐offs associated with copulation and oviposition that may have life‐history consequences via their effects on immune system function.
Ice nucleation and freezing tolerance in New Zealand alpine and lowland weta, Hemideina spp. (Orthoptera; Stenopelmatidae)
Authors: Sinclair Brent J. , Worland M. Roger , And . , Wharton David A.
Published: March 2003

Abstract.The alpine tree weta Hemidiena maori Pictet et Saussure (Orthoptera: Stenopelmatidae) is a large, flightless insect found above the treeline on many of the mountain ranges of the South Island of New Zealand. The population found on the Rock and Pillar Range, Central Otago has been identified as freezing tolerant with a haemolymph ice nucleating agent. The ability of H. maori to survive freezing is compared to the lowland weta Hemideina thoracica Walker and H. crassidens Blanchard, both of which are able to survive the formation of some ice in their bodies. Mortality is associated with time spent frozen in H. thoracica, and it is hypothesized that this species is killed when a critical proportion of its body water is frozen. All five subalpine and alpine populations of H. maori surveyed were found to be freezing tolerant.

Comparison of temperatures of first nucleation and mean supercooling point of haemolymph droplets suggest that haemolymph ice nucleating activity varies between populations of H. maori. Hemideina maori collected from the Mt Cook region appear to lack a haemolymph ice nucleator. This population is nevertheless freezing tolerant, suggesting that the haemolymph ice nucleating agent described in H. maori is not essential for freezing tolerance. Hemideina crassidens and H. ricta Hutton, both of which are found in lowland habitats, also had high mean supercooling point and temperatures of first nucleation of haemolymph droplets, suggesting that these species also have a haemolymph ice nucleator.

Comparison of ice nucleation characteristics of haemolymph and faecal material (representing gut contents) suggests that gut nucleators in H. maori may be at least as efficient as the haemolymph nucleator. It is concluded that freezing tolerance is probably not an adaptation to the alpine environment. This highlights the need for inter‐ and intraspecific comparative studies if physiological data are to be used to draw evolutionary conclusions.
The attractiveness of different odour sources from the fruit–host complex on Leptopilina boulardi, a larval parasitoid of frugivorous Drosophila spp.
Authors: Couty AudE. , Kaiser Laure , And Dominique HueT. , Pham‐Delegue Minh‐Hà.
Published: March 2003

In parasitoid insects, successful offspring development depends on the female’s ability to find a suitable host. Specific recognition is often based on responses to olfactory cues, but their source and nature have rarely been determined.

–This paper deals with the recognition of odours involved in host location by Leptopilina boulardi[Barbotin, Carton & Kelner‐Pillault] (Hymenoptera: Eucoilidae), a larval parasitoid of Drosophila species that develops in mature fruits. The nature and origin of volatile stimuli recognized among odours of the host–fruit complex, and the effect of learning on this recognition, were investigated. Oriented responses to these odours were observed in a four‐armed olfactometer and were analysed with the
observer software (Noldus Information Technology). Fruit odours alone (banana and pear) were not spontaneously attractive to naive parasitoids, whereas naturally‐infested bananas were highly attractive. The attraction was related to the odour that adult Drosophila left on the substrate but not to Drosophila oviposition activity or larval development. A synergism between some fruit odours (banana and pear) and the odour left by adult Drosophila on damp filter paper was observed. However, when testing a non‐fruit substrate (mushroom), no synergism was observed. Thus, female L. boulardi may innately recognize host–food substrate odours associated with odours from the adult stage of their host. In addition, an oviposition experience on an infested banana allows L. boulardi females to memorise the fruit odour itself through associative learning. The adaptive significance of this process is discussed.
Communication between the fungus garden and workers of the leaf‐cutting ant, Atta sexdens rubropilosa, regarding choice of substrate for the fungus
Authors: North R. D. , Jackson C. W. , Howse P. E.
Published: March 2003

Bait made from orange peel, containing the fungicide cycloheximide, was initially harvested by workers of Atta sexdens rubropilosa (Forel) and incorporated into the fungus garden as substrate for the fungus. The bait was subsequently rejected by the worker ants days later. Exposure of the fungus to cycloheximide, in laboratory sub‐colonies, resulted in the fungus being ‘stressed’. By interchanging normal fungus garden with ‘stressed’ fungus garden, a change in the foraging behaviour of the workers was evident.

–Two hypotheses to explain the behavioural changes were tested: a volatile semiochemical is produced by the fungus which affects the foragers directly, or contact between workers (and fungus garden) is necessary for information regarding fungal substrate to be transmitted through the worker force. When pairs of sub‐colonies were connected (one colony of each pair exposed to cycloheximide in the bait) and workers were initially prevented from passing from one colony to the other, one colony continued to forage on orange bait while the other did not. When both colonies were allowed to make full contact then both colonies failed to accept orange bait. This discounted the first hypothesis, but supported the second, as a highly volatile chemical should be able to diffuse between colonies. When large foragers were prevented from making contact with the second colony, the information may be communicated by smaller workers.
Small‐scale vegetation patterns in the parental environment influence the phase state of hatchlings of the desert locust
Authors: Despland E. , Simpson S. J.
Published: March 2003

Desert locusts (Schistocerca gregaria Forskål (Orthoptera: Acrididae)) change phase in response to population density. Solitarious insects avoid one another; when crowded, they shift to the gregarious phase and aggregate. Laboratory experiments and individual‐based modelling have shown that small‐scale resource distribution can affect locust phase state via an influence on crowding. Laboratory work has also shown that parental phase state is transmitted to offspring via maternal inheritance. These effects had not been investigated in the field previously. We maintained small populations of adult desert locusts in semi‐field enclosures with different distribution patterns of a single plant species (Hyoscyamus muticus L. (Solanaceae)). The offspring of locusts exposed to more clumped patterns of vegetation exhibited more gregarious behaviour when tested in a behavioural phase assay than did progeny from parents left in enclosures with more scattered vegetation. These effects on nymphal behaviour appeared to be mediated by influences of resource distribution on adult phase state. Phase state in small semi‐field populations was influenced by small‐scale vegetation distribution. Phase differences engendered by environmental structure were maintained in time and transmitted to progeny.
Sperm transfer during mating, movement of sperm in the female reproductive tract, and sperm precedence in the common cutworm Spodoptera litura
Authors: Seth R. K. , Kaur J. J. , Rao D. K. , Reynolds Stuart E.
Published: March 2003

Abstract. Mating behaviour, sperm transfer and sperm precedence were studied in the moth Spodoptera litura (Fabr.) (Lepidoptera: Noctuidae). There existed a rhythmic, diel pattern of mating behaviour of this moth during the scotophase, presumably set with respect to an endogenous activity rhythm. Approximately 30 min after copulation had started, the formation of the corpus of the spermatophore began in the bursa copulatrix of the female moth, but full inflation of the corpus was not completed until 45–60 min after mating had started. The mature spermatophore contained about 350 eupyrene sperm bundles and a large number of individual (loose) apyrene spermatozoa. The mating status and the age of the male insect influenced the number of sperm transferred to the female within the spermatophore, and also affected the consequent fertility. There was no evidence of sperm reflux within the male tract. Within the female, dissociation of eupyrene sperm bundles was evident within the spermatophore less than 15 min after the completion of mating. Spermatozoa began to move from the bursa (in which the spermatophore is lodged) into the spermatheca 30–45 min after the end of the copulation, and the quantity of sperm in the spermatheca reached a plateau at 90 min after mating. Apyrene sperm reached the spermatheca first, followed by eupyrene sperm. Examination of total (apyrene plus eupyrene) sperm in the female tract showed that 86% of mated females received an apparently normal amount of total sperm from the male. Examination of eupyrene sperm alone showed that 81% of matings resulted in an apparently normal transfer of eupyrene sperm. A small proportion (approximately 8%) of the matings, however, were identified as transferring a clearly subnormal quantity of eupyrene sperm to the spermatheca. The eggs produced as a result of such pairings displayed much reduced fertility (about 43%) compared to those from matings confirmed to have transferred normal quantities of sperm, which showed about 92% fertility. This shows that the availability of eupyrene sperm in the spermatheca may be an important constraint on fertility in normal populations of insects. In the laboratory, S. litura females exhibited multiple matings. Of the females, 93% mated, and the mean frequency of mating was 1.69. Mating with a fertile male led to the oviposition of an increased number of eggs. This effect continued even when the female subsequently mated with an infertile male. Displacement of sperm from previous matings is known to be an important factor in the evolution of multiple mating strategies. Our results on sperm utilization by S. litura indicated that after a second mating, the sperm utilized for subsequent fertilization were almost exclusively from the last mating with little mixing. The proportion of eggs fertilized by sperm from the second mating (P2) was calculated as 0.95, indicating almost complete sperm precedence from the last mating.
Flight behaviour of males of two moths,Cadra cautellaandPectinophora gossypiella, in homogeneous clouds of pheromone
Authors: Justus Kristine A. , Cardé Ring T.
Published: March 2003

AbstractIt is thought that orientation by male moths along pheromone plumes is guided by interception of filaments of pheromone along that plume and that clean air gaps are required for upwind progress. Given that several investigations have determined that cells sensitive to pheromone can resolve only low rates of encounter with pheromone filaments, generally up to 10 pulses/s, it would appear that individual filaments encountered at higher rates would not be resolved by the insects' sensory system and therefore the stimulus would be perceived as a non‐flickering signal. Behaviourally, this has been thought to be expressed as the cessation of upwind progress. Previous studies withCadra cautella(Walker) (Lepidoptera: Pyralidae) demonstrated that upwind flight by these males is not inhibited in rapidly pulsed plumes. Therefore, to determine whether a flickering signal is required for upwind progress byC. cautella, males were introduced to homogeneous clouds of pheromone in a wind tunnel and their behaviour recorded. For comparison,Pectinophora gossypiella(Saunders) (Lepidoptera: Gelechiidae), a species from a long‐diverged lineage, was also used. Upwind progress byC. cautellais not impeded by the constant olfactory signal provided by a homogeneous cloud of pheromone, but this is not true forP. gossypiella. Furthermore, althoughC. cautelladirects its flight upwind in a homogeneous cloud, its heading is not always due upwind. Potential mechanisms are discussed. It is suggested thatC. cautelladoes not require a flickering signal to progress upwind.
Aphid parasitoids detect that an alien plant was present nearby during their development
Authors: Van Emden H. F. , Eletherianos I. , Rose Juliet , Douloumpaka Sophia , Pettersson J.
Published: March 2003

Abstract Glasshouse and laboratory experiments were conducted with Aphidius rhopalosiphi parasitizing Metopolophium dirhodum to test whether the presence in the same environment of another plant species (tomato or marigold) induced aerial allelopathy in wheat plants.

Emerging parasitoids were offered the choice of two odours of wheat plants in an olfactometer – wheat grown alone and wheat grown in the presence of the second plant species.

Female parasitoids responded more strongly than males, but both sexes preferred the odour of wheat grown in the environment in which they had developed (i.e. with or without the second plant species present).

Moving the tomato plants from the cages where they had been placed with wheat to the cages that had previously had wheat alone just before the aphid mummy formed showed that the odour environment the emerging parasitoid responded to was that of the mummy rather than that of the developing parasitoid larva. From this it was concluded that the parasitoids in the olfactometer were responding not only to wheat volatiles, but also to tomato volatiles absorbed on the surface of the mummy and encountered by the emerging adult parasitoid.

By excising the parasitoid pupa from the mummy formed on one wheat cultivar, and offering the emerging parasitoids the surface of aphid mummies formed on a different cultivar, it was confirmed that olfactometer responses represented a learning of the chemistry of the surface of the mummy encountered at or after emergence.
Effects of VA mycorrhizal colonization on photosynthesis and biomass production of Trifolium repens L.
Authors: Wright D. P. , Scholes J. D. , Read D. J.
Published: March 2003

The influence of vesicular–arbuscular mycorrhizal (M) colonization on biomass production and photosynthesis of Trifolium repens L. was investigated in two experiments in which the foliar nitrogen and phosphorus contents of non‐mycorrhizal (NM) plants were manipulated to be no lower than that of M plants. Throughout both experiments there was a stimulation in the rate of CO2 assimilation of the youngest, fully expanded leaf of M compared with NM plants. In addition, M plants exhibited a higher specific leaf area compared with NM plants, a response that maximized the area available for CO2 assimilation per unit of carbon (C) invested. Despite the increased rate of photosynthesis in M plants there was no evidence that the additional C gained was converted to biomass production of M plants. It is suggested that this additional C gained by colonized plants was allocated to the mycorrhizal fungus and that it is the fungus, by acting as a sink for assimilates, that facilitated the stimulation in the rate of photosynthesis of the plant partner.
Photosynthesis of Ectocarpus siliculosus in red light and after pulses of blue light at high pH – evidence for bicarbonate uptake
Authors: Schmid
Published: March 2003

Pulses of blue light cause stimulation of red light saturated photosynthesis in Ectocarpus siliculosus, because blue light activates the operation of a pathway for inorganic carbon (Ci) acquisition by inducing the mobilization of CO2 from an intermediate metabolite. In the absence of exogenous Ci, photosynthetic rates roughly equal those of CO2 release by respiration. In seawater of pH 9·5 (2·3 mol m–3 total Ci, but concentrations of free CO2 below 0·2 mmol m–3), photosynthesis was clearly above these rates, although they were only ≈ 30% of those in normal seawater (≈ pH 8). The degree and the time course of the stimulations of photosynthesis by pulses of blue light were unaltered at high pH. Essentially the same characteristics were found after buffering or in the presence of acetazolamide, an inhibitor of extracellular carbonic anhydrase activity. Therefore, it is concluded that Ectocarpus is able to directly take up HCO3– in addition to CO2 (uptake of CO32– cannot be excluded). The dependence of photosynthesis on Ci at pH 9·5 was biphasic, with Ci below 0·2 mol m–3 having no effect at all. In Ci‐free seawater, the shapes of the stimulations after blue light pulses differed for pH 6, pH 8 and pH 9·5. At low pH, only the fast peak (maximum ≈ 5 min after blue light) was detected, whereas at high pH mainly the slow peak (maximum ≈ 20 min after blue light) was observed. At the intermediate pH 8, both peaks were present. As inhibition of total carbonic anhydrase by ethoxyzolamide brought out the fast peak of the stimulations at pH 9·5 it is concluded that the fast component was due to a transient disequilibrium of an intracellular pool of Ci which, after blue light, was fed by CO2 released from the postulated storage intermediate.