bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Neurotensin on the Organization of Activity in Supraoptic Nucleus Cells in Virgin and Lactating Rats
Authors: Johnstone L. E. , Leng G. , Brown C. H. 
Published: June 2004

AbstractNeurotensin increases the firing rate of supraoptic nucleus oxytocin and vasopressin neurones in vitro and induces Fos protein expression in the supraoptic nucleus in vivo. Here, we used extracellular single‐unit electrophysiological recording combined with local microdialysis administration of neurotensin (1 mM at 2 µl/min) to investigate the effects of locally applied neurotensin on the firing of oxytocin and vasopressin neurones in urethane‐anaesthetized virgin and lactating rats. Neurotensin decreased the mean firing rate of oxytocin cells in virgin, but not lactating, rats. In addition, neurotensin increased the index of dispersion (a measure of the variability of firing) in virgin, but not lactating, rats. By contrast to oxytocin cells, neurotensin increased the mean firing rate of vasopressin cells in both virgin and lactating rats, but did not alter the index of dispersion. The increase in firing of phasic vasopressin cells was achieved through an increase in intraburst frequency (rather than an increase in burst duration or decrease in interburst interval), which resulted from a reduction of the spike‐frequency adaptation that develops over the course of phasic bursts. Thus, neurotensin has differential effects on activity patterning in oxytocin and vasopressin cells and the effects on oxytocin cells, but not vasopressin cells, depend upon the physiological status of the animal. The increase in the variability of firing of oxytocin cells induced by neurotensin in virgin rats, but not in lactating rats, suggests that neurotensin (or other neurotransmitters/neuromodulators with similar actions) might establish conditions that predispose oxytocin cells to fire in milk‐ejection bursts in lactating rats.
Role of Leptin in Orexigenic Neuropeptide Expression During Lactation in Rats
Authors: Crowley W. R. , Ramoz G. , Torto R. , Kalra S. P. 
Published: June 2004

AbstractThe expression of neuropeptide Y (NPY) and agouti‐related peptide (AgRP), both of which are important neuropeptides involved in regulation of energy balance and hormone secretion, is up‐regulated in the arcuate nucleus during lactation in rodents. The present study tested whether reductions in circulating insulin and/or leptin that occur in lactation provide the critical signals to these systems. Lactating female rats received 3‐day infusions of either bovine insulin or recombinant rat leptin via Alzet Osmotic minipumps® implanted subcutaneously in regimens designed to restore serum concentrations of these hormones to the higher non‐lactating level. Compared to non‐lactating rats in diestrus, lactating rats displayed significantly lower serum concentrations of insulin and leptin, and significantly increased NPY peptide concentrations in the paraventricular nucleus (PVN) and median eminence, and AgRP mRNA in the arcuate nucleus. Infusion of leptin in lactating females significantly increased serum concentrations of leptin and significantly reduced NPY concentrations in the PVN and median eminence, and decreased NPY and AgRP mRNAs in the arcuate nucleus. The same effects were produced by infusion of insulin in lactating rats, which restored both insulin and leptin concentrations in serum. The levels of pro‐opiomelanocortin mRNA in the arcuate nucleus were not different in non‐lactating and lactating females, and were not altered by leptin or insulin treatment. These findings support the hypothesis that the reduction in circulating leptin during lactation contributes to increased expression of NPY and AgRP in hypothalamic systems involved in the behavioural and neuroendocrine adaptations to lactation.
Update on human cytomegalovirus in destructive periodontal disease
Authors: Slots J. 
Published: June 2004

Aim:  Human cytomegalovirus (HCMV), a herpesvirus, is discussed in this review as it relates to destructive periodontal disease in humans.Results:  HCMV genomic sequences, detected by polymerase chain reaction identification, occur with elevated frequency in severe adult periodontitis, localized and generalized aggressive (juvenile) periodontitis, Papillon–Lefèvre syndrome periodontitis, acute necrotizing ulcerative gingivitis, and periodontal abscesses.Discussion:  Herpesviruses establish lifelong persistent infections. HCMV infection involves an asymptomatic latent phase interrupted by periods of recrudescence where viral replication and possibly clinical disease become manifest. HCMV reactivation is triggered by a number of immunosuppressive factors, some of which have been shown also to be risk factors/indicators of periodontitis. HCMV periodontal infection may cause release of tissue‐destructive cytokines, overgrowth of pathogenic periodontal bacteria, and initiation of cytotoxic or immunopathologic events.Conclusions:  A growing body of data supports the concept that HCMV contributes to severe types of periodontal disease. HCMV infection of the periodontium may alter the immune control of resident microorganisms and be important in a multistage pathogenesis of periodontitis involving viral activation, periodontopathic bacteria, and host immune responses. Understanding the significance of HCMV and other herpesviruses in the development of periodontal disease may have important therapeutic implications. Vaccines against HCMV, which are in various stages of development, need to be evaluated for their ability to decrease the incidence of destructive periodontal disease.
Breast milk substitutes in Hong Kong
Authors: Nelson EAS , Chan CW , Yu CM 
Published: June 2004

Objective:  In 1981 the World Health Assembly (WHA) adopted the International Code of Marketing of Breast Milk Substitutes (the Code) to support breastfeeding. Despite improving trends, Hong Kong has low rates of breastfeeding compared to other developed countries.Methods:  We surveyed companies marketing breast milk substitutes in Hong Kong to determine self‐reported adherence to the Code. Companies were informed that individual responses would not be published and seven of nine companies responded to the questionnaire.Results:  The majority of respondents promoted infant and follow‐on formula in hospitals and provided free supplies of infant formula to hospitals. Follow‐on formula and weaning foods were promoted in shops and to the general public and free samples were given to mothers reflecting a belief that, despite WHA resolutions, follow‐on formula is not a breast milk substitute.Conclusions:  Transnational companies should follow the Code and subsequent WHA resolutions equally in all countries.
Motor Performance Checklist for 5‐year‐olds: A tool for identifying children at risk of developmental co‐ordination disorder
Authors: Gwynne K , Blick B 
Published: June 2004

Objective: The aim of this study was to further evaluate the ‘Motor Performance Checklist for 5‐year‐olds’, an instrument which had been piloted with some success and reported via this journal in 1996.Method: Both validity and reliability in identifying children in most need of paediatric occupational therapy services was assessed. The Motor Performance Checklist was compared against a chosen ‘gold standard’ test, The Bruininks‐Oseretsky test of Motor Proficiency, in a group of 141 5‐year‐old children.Results: Correlations of 0.72 and 0.85 were found between the tests. The checklist was found to have a sensitivity of 83% and a specificity of 98%. Positive predictive validity was found to be 72% and negative predictive validity 99%. Interrater reliability ranged between 0.79 and 0.99 and intrarater reliability was 0.77.Conclusions: These results indicate that the Motor Performance Checklist has the potential to assist in identifying children in most need of referral to community occupational therapy services.
Comparison of selected reasons for hospitalization of children among children’s/tertiary hospitals, Australia, 1996−97 and 1997−98
Authors: Ford JB , Henry RL , Sullivan EA 
Published: June 2004

Objectives:  To describe the major characteristics of admissions to children’s/tertiary hospitals (compared to other hospitals) and to compare characteristics of local and non‐local admissions to specialist children's hospitals.Methods:  A cross‐sectional analysis of a routinely collected data set of hospitalizations in Australia in 1996−97 and 1997−98.Results:  Hospital‐specific proportions of asthma and bronchitis, tonsillectomy and/or adenoidectomy and gastroenteritis varied considerably. Multivariate analysis comparing the characteristics of admitted patients by locality showed that non‐local admissions of patients with asthma and bronchitis and gastroenteritis to selected children's hospitals were significantly more likely to be Indigenous children and/or children who had been transferred from another hospital. Non‐local admissions of tonsillectomy and/or adenoidectomy patients to selected hospitals were significantly more likely to be public patients.Conclusions:  Differences in the characteristics of admitted patients to children's hospitals by locality raise issues about equality of access and availability of appropriate services for these children and their families.
Epitope Structure of the
Bordetella pertussis
Protein P.69 Pertactin, a Major Vaccine Component and Protective Antigen
Authors: Hijnen Marcel , Mooi Frits R. , van Gageldonk Pieter G. M. , Hoogerhout Peter , King Audrey J. , Berbers Guy A. M. 
Published: June 2004

ABSTRACT

Bordetella pertussis
is reemerging in several countries with a traditionally high vaccine uptake. An analysis of clinical isolates revealed antigenic divergence between vaccine strains and circulating strains with respect to P.69 pertactin. Polymorphisms in P.69 pertactin are mainly limited to regions comprised of amino acid repeats, designated region 1 and region 2. Region 1 flanks the RGD motif, which is involved in adherence. Although antibodies against P.69 pertactin are implicated in protective immunity, little is known about the structure and location of its epitopes. Here we describe the identification by pepscan analysis of the locations of mainly linear epitopes recognized by human sera and mouse monoclonal antibodies (MAbs). A total of 24 epitopes were identified, and of these only 2 were recognized by both MAbs and human antibodies in serum. A number of immunodominant epitopes were identified which were recognized by 78 to 93% of the human sera tested. Blocking experiments indicated the presence of high-avidity human antibodies against conformational epitopes. Human antibodies against linear epitopes had much lower avidities, as they were unable to block MAbs. Pepscan analyses revealed several MAbs which bound to both region 1 and region 2. The two regions are separated by 289 amino acids in the primary structure, and we discuss the possibility that they form a single conformational epitope. Thus, both repeat regions may serve to deflect the immune response targeted to the functional domain of P.69 pertactin. This may explain why the variation in P.69 pertactin is so effective, despite the fact that it is limited to only two small segments of the molecule.
Mycobacterium aviumsubsp.paratuberculosisFibronectin Attachment Protein Facilitates M-Cell Targeting and Invasion through a Fibronectin Bridge with Host Integrins
Authors: Secott T. E. , Lin T. L. , Wu C. C. 
Published: June 2004

ABSTRACTEfficient attachment and ingestion ofMycobacterium aviumsubsp.paratuberculosisby cultured epithelial cells requires the expression of a fibronectin (FN) attachment protein homologue (FAP-P) which mediates FN binding byM. aviumsubsp.paratuberculosis. Invasion of Peyer's patches byM. aviumsubsp.paratuberculosisoccurs through M cells, which, unlike other intestinal epithelial cells, express integrins on their luminal faces. We sought to determine if the interaction between FAP-P ofM. aviumsubsp.paratuberculosisand soluble FN enabled targeting and invasion of M cells byM. aviumsubsp.paratuberculosisin vivo via these surface integrins. Wild-type and antisense FAP-P mutantM. aviumsubsp.paratuberculosisstrains were injected alone or coinjected with blocking peptides or antibodies into murine gut loops, and immunofluorescence microscopy was performed to assess targeting and invasion of M cells byM. aviumsubsp.paratuberculosis. NonopsonizedM. aviumsubsp.paratuberculosispreferentially invaded M cells in murine gut loops. M-cell invasion was enhanced 2.6-fold whenM. aviumsubsp.paratuberculosiswas pretreated with FN. Invasion of M cells by the antisense FAP-P mutant ofM. aviumsubsp.paratuberculosiswas reduced by 77 to 90% relative to that observed for the control strains. Peptides corresponding to the RGD and synergy site integrin recognition regions of FN blockedM. aviumsubsp.paratuberculosisinvasion of M cells by 75 and 45%, respectively, whereas the connecting segment 1 peptide was noninhibitory. Antibodies against the α5, αV, β1, and β3 integrin subunits inhibited M-cell invasion by 52 to 73%. The results indicate that targeting and invasion of M cells byM. aviumsubsp.paratuberculosisin vivo is mediated primarily by the formation of an FN bridge formed between FAP-P ofM. aviumsubsp.paratuberculosisand integrins on M cells.
Zipper-Like Internalization of Dr-PositiveEscherichia coliby Epithelial Cells Is Preceded by an Adhesin-Induced Mobilization of Raft-Associated Molecules in the Initial Step of Adhesion
Authors: Kansau Imad , Berger Cédric , Hospital Maxime , Amsellem Raymonde , Nicolas Valérie , Servin Alain L. , Bernet-Camard Marie-Françoise 
Published: June 2004

ABSTRACTWe undertook a study of the mechanism by which Dr-positive bacteria invade epithelial cells. Our findings show that Dr-positive bacteria enter via a zipper-like mechanism that is independent of the Dr-induced mobilization of F-actin and of the signaling molecules that control Dr-induced F-actin rearrangements. We also observed that Dr-positive IH11128 bacteria entered cells that were positive for the caveola marker VIP21/caveolin (HeLa and Caco-2/Cav-1 cells) to the same extent as those that were not (parental Caco-2 cells). Using fluorescence labeling and confocal laser scanning microscopy, we provide evidence that during the adhesion step, the α5β1 integrin, which plays a pivotal role in Afa/Dr diffusely adheringEscherichia colibacterial entry, is mobilized around adhering Dr-positive bacteria. We show that the receptor for Afa/Dr adhesins, glycosylphosphatidylinositol-anchored CD55; the raft marker, ganglioside GM1; and VIP21/caveolin are all recruited around adhering Dr-positive bacteria. We also observed that extracting membrane cholesterol with methyl-β-cyclodextrin (MBCD) did not affect the recruitment of CD55, GM1, or β1 integrin to adhering Dr-positive bacteria. In contrast, extracting or changing membrane-bound cholesterol by means of drugs that modify lipid rafts (MBCD, filipin III, or mevalonate plus lovastatin plus MBCD) inhibited the entry of Dr-positive IH11128 both into cells that expressed VIP21/caveolin (HeLa and Caco-2/Cav-1 cells) and into those that did not (parental Caco-2 cells). Finally, restoring cholesterol within the cell membrane of MBCD-treated cells restored Dr-positive IH11128 internalization.
Isolation of a Chromosomal Region ofKlebsiella pneumoniaeAssociated with Allantoin Metabolism and Liver Infection
Authors: Chou Huei-Chi , Lee Cha-Ze , Ma Li-Chen , Fang Chi-Tai , Chang Shan-Chwen , Wang Jin-Town 
Published: June 2004

ABSTRACTKlebsiella pneumoniaeliver abscess with metastatic complications is an emerging infectious disease in Taiwan. To identify genes associated with liver infection, we used a DNA microarray to compare the transcriptional profiles of three strains causing liver abscess and three strains not associated with liver infection. There were 13 clones that showed higher RNA expression levels in the three liver infection strains, and 3 of these 13 clones contained a region that was absent in MGH 78578. Sequencing of the clones revealed the replacement of 149 bp of MGH 78578 with a 21,745-bp fragment in a liver infection strain, NTUH-K2044. This 21,745-bp fragment contained 19 open reading frames, 14 of which were proven to be associated with allantoin metabolism. The K2044 (ΔallS) mutant showed a significant decrease of virulence in intragastric inoculation of BALB/c mice, and the prevalence of this chromosomal region was significantly higher in strains associated with liver abscess than in those that were not (19 or 32 versus 2 of 94;P= 0.0001 [χ2test]). Therefore, the 22-kb region may play a role inK. pneumoniaeliver infection and serve as a marker for rapid identification.
Oral Tolerance in T Cells Is Accompanied by Induction of Effector Function in Lymphoid Organs after Systemic Immunization
Authors: Parameswaran Neetha , Samuvel Devadoss John , Kumar Ramesh , Thatai Sangeeta , Bal Vineeta , Rath Satyajit , George Anna 
Published: June 2004

ABSTRACTThe physiological ramifications of oral tolerance remain poorly understood. We report here that mice fed ovalbumin (OVA) exhibit oral tolerance to subsequent systemic immunization with OVA in adjuvant, and yet they clear systemic infection with a recombinant OVA-expressing strain ofSalmonella entericaserovar Typhimurium better than unfed mice do. Mice fed a sonicated extract ofS. entericaserovar Typhimurium are also protected against systemic bacterial challenge, and the protection is Th1 mediated, as feeding enhances clearance in interleukin-4-null (IL-4−/−) and IL-10−/−mice but not in gamma interferon-null (IFN-γ−/−) mice. When T-cell priming in vivo is tracked temporally in T-cell receptor-transgenic mice fed a single low dose of OVA, CD4 T-cell activation and expansion are restricted largely to mucosal lymphoid organs. However, T cells from spleens and peripheral lymph nodes of fed mice proliferate and secrete IFN-γ when restimulated with OVA in vitro, indicating the presence of primed T cells in systemic tissues following oral exposure to antigen. Nonetheless, oral tolerance can be observed in the fed mice as reduced recall responses following subsequent systemic immunization with OVA in adjuvant. Soluble OVA administered systemically has similar effects in vivo, and the “tolerance” seen in both cases can be partially reversed if the initial priming is made more immunogenic. Together, the results indicate that antigen exposure under poor adjuvantic conditions, whether oral or systemic, may lead to T-cell commitment to effector rather than proliferative capabilities, necessitating a reassessment of therapeutic modalities for induction of oral tolerance in allergic or autoimmune states.
Infection withToxoplasma gondiiReduces Established and Developing Th2 Responses Induced byNippostrongylus brasiliensisInfection
Authors: Liesenfeld Oliver , Dunay Ildiko R. , Erb Klaus J. 
Published: June 2004

ABSTRACTOral infection of C57BL/6 mice with 100 cysts of the protozoan parasiteToxoplasma gondiiresults in the development of small intestinal Th1-type immunopathology. In contrast, infection with intestinal helminths results in the development of protective Th2-type responses. We investigated whether infection with the helminthNippostrongylus brasiliensisinfluences the development ofT. gondii-induced Th1 responses and immunopathology in C57BL/6 mice infected withT. gondii. Prior as well as simultaneous infection of mice withN. brasiliensisdid not alter the course of infection with 100 cysts ofT. gondii. Coinfected mice produced high levels of interleukin-12 (IL-12) and gamma interferon (IFN-γ), developed small intestinal immunopathology, and died at the same time as mice infected withT. gondii. Interestingly, local and systemicN. brasiliensis-induced Th2 responses, including IL-4 and IL-5 production by mesenteric lymph node and spleen cells and numbers of intestinal goblet cells and blood eosinophils, were markedly lower in coinfected than inN. brasiliensis-infected mice. Similar effects were seen when infection with 10T. gondiicysts was administered following infection withN. brasiliensis. Infection of C57BL/6 mice with 10T. gondiicysts prior to coinfection withN. brasiliensisinhibited the development of helminth-induced Th2 responses and was associated with higher and prolongedN. brasiliensisegg production. In contrast, oral administration ofToxoplasmalysate prior toN. brasiliensisinfection had only a minor and short-lived effect on Th2 responses. Thus,N. brasiliensis-induced Th2 responses fail to alterT. gondii-induced Th1 responses and immunopathology, most likely because Th1 responses develop unchanged in C57BL/6 mice with a prior or simultaneous infection withN. brasiliensis. Our findings contribute to the understanding of immune regulation in coinfected animals and may assist in the design of immunotherapies for human Th1 and Th2 disorders.
In Vivo Interleukin-6 Protects Neutrophils from Apoptosis in Osteomyelitis
Authors: Asensi Víctor , Valle Eulalia , Meana Alvaro , Fierer Joshua , Celada Antonio , Alvarez Victoria , Paz José , Coto Eliecer , Carton José Antonio , Maradona José Antonio , Dieguez Angeles , Sarasúa Julián , Ocaña Marcos G. , Arribas José Manuel 
Published: June 2004

ABSTRACTPolymorphonuclear neutrophils are critical for resolution of bacterial infections. In tissues, most of the neutrophils quickly die through apoptosis. Using propidium iodide DNA staining and DNA gel electrophoresis, we found that spontaneous apoptosis of neutrophils from patients suffering osteomyelitis (n= 52) was significantly decreased in relation to control neutrophils (n= 20) (40.2% ± 25.2% versus 54.5% ± 23.5%;P< 0.03). Incubation of neutrophils from normal volunteers with sera from patients with osteomyelitis reduced apoptosis from 79.1% ± 14.8% in control sera to 62.2% ± 18.7% in osteomyelitis sera. A significant increase of serum interleukin-6 (IL-6) and IL-1α was found in osteomyelitis (IL-6, 8.8 ± 11.9 pg/ml versus 1.8 ± 1.2 pg/ml in controls [P< 0.004]; IL-1α, 3.8 ± 6.4 pg/ml versus 1.0 ± 2.2 pg/ml in controls [P< 0.02]). No differences in the levels of other cytokines, such as tumor necrosis factor alpha, were found. There was an inverse correlation between IL-6 levels and neutrophil apoptosis (r= −0.855;P< 0.007), but this was not the case for other cytokines. The antiapoptotic effect of the osteomyelitis sera was reversed with anti-IL-6 antibodies (P< 0.03) and was reproduced with recombinant human IL-6 (P< 0.001). The longer life span of neutrophils in osteomyelitis induced by IL-6 could contribute to the tissue damage that occurs in these chronic bone infections.