SEARCH · PubMed Health

Results for “ADE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,189 records · Page 66Linked to original sources

PubMed2005

Immune activation is associated with reduced skeletal muscle mass and physical function in chronic heart failure.

BACKGROUND: Chronic heart failure is characterized by immune activation and increased circulating levels of cytokines. Whether humoral factors contribute to the peripheral manifestations of the heart failure syndrome, such as muscle atrophy and reduced physical work capacity, however, is not clear. METHODS: We measured circulating cytokines (tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6)), their soluble receptors (sTNF-alpha RII, IL-6sR), markers of immune activation (C-reactive protein (CRP)), muscle mass, aerobic capacity and muscle strength in 10 patients with heart failure (mean +/- S.E.; 63 +/- 3 years) and 11 controls (70 +/- 3 years). RESULTS: Heart failure patients exhibited decreased aerobic capacity (P < 0.01) and leg muscle strength (P < 0.05). Reduced muscle strength persisted in heart failure patients after statistical adjustment for differences in skeletal muscle size. All inflammatory markers were increased in heart failure patients (P < or = 0.05 to P < 0.01) compared to controls, with the exception of TNF-alpha. Despite no group differences in TNF-alpha, higher concentrations of this cytokine were correlated to lower skeletal muscle mass in the combined study population (range of r-values: -0.436 to -0.545; P < 0.05 to P < 0.02), as were IL-6 levels (range of r-values: -0.438 to -0.443; P < 0.05). TNF-alpha, sTNF-alpha RII, IL-6 and CRP showed strong negative relationships to aerobic capacity (range of r-values: -0.579 to -0.751; P < 0.01 to P < 0.001). In addition, elevated levels of IL-6 and TNF-alpha were associated with reduced leg and forearm skeletal muscle strength (range of r-values: -0.440 to -0.674; P < 0.05 to P < 0.01). Finally, correlations between cytokines and functional measures were present when heart failure patients were analyzed separately (range of r-values: -0.646 to -0.673; P < 0.05). CONCLUSIONS: Our results suggest that circulating cytokines are related to both skeletal muscle mass and physical function. These findings provide further evidence to support the hypothesis that immune activation contributes to skeletal muscle atrophy and reduced functional capacity in heart failure patients.

Aged↗

PubMed2006

Association of anthropometric indices with cardiovascular disease risk factors among children and adolescents: CASPIAN Study.

BACKGROUND: For the first time in Iran, and to the best of our knowledge in Asia, we assessed the anthropometric indices most closely correlated to cardiovascular disease (CVD) risk factors in a large nationally representative sample of children and adolescents to be used as a simple tool for identifying those at risk. METHODS: This multi-center study was performed among a representative sample of 4811 school students (2248 boys and 2563 girls) aged 6-18 years, as part of the baseline survey of a national surveillance system. Anthropometric indices and CVD risk factors were measured using standard protocols, and their correlation was analyzed by using Receiver Operator Characteristic (ROC) curves and partial correlation. RESULTS: The most prevalent CVD risk factors were low HDL-C (28%), followed by hypertriglyceridemia (20.1%), and overweight (17%). The ROC analyses showed that among boys, all anthropometric indices had the same association with CVD risk factors in 6-9.9-year-age group, while in the 10-13.9 and 14-18-year-age groups, respectively waist circumference (WC) and body mass index (BMI) were the best in distinguishing CVD risk factors. Among girls, these indices were respectively BMI and waist to stature ratio (WSR); WC and WSR; and WC. In the partial correlation analysis, in boys, the highest coefficient was found for BMI; BMI and WC; and for WC and WSR; in girls, these indices were BMI; WC and WSR; and BMI respectively. CONCLUSIONS: In the present study, BMI, WC and WSR were the most appropriate in predicting CVD risk factors. It may be clinically useful in the pediatric population to routinely measure WC and WSR in addition to BMI as a screening tool to identify high-risk youth.

Adolescent↗

PubMed2006

Carbon-13 labeling for improved tracer depth profiling of organic materials using secondary ion mass spectrometry.

13C labeling is introduced as an alternative to deuterium labeling for analysis of organic materials using secondary ion mass spectrometry (SIMS). A model macromolecular system composed of polystyrene (PS) and poly(methyl methacrylate) (PMMA) was used to compare the effects of isotopic labeling using both deuterium substitution (dPS) and 13C labeling (13C-PS). Clear evidence is shown that deuterium labeling does introduce changes in the thermodynamic properties of the system, with the observation of segregation of dPS to an hPS:dPS/hPMMA interface. This type of behavior could significantly impact many types of investigations due to the potential for improper interpretation of experimental results as a consequence of labeling-induced artifacts. 13C labeling is shown to provide a true tracer for analysis using SIMS.

Carbon Isotopes↗

PubMed2006

A serological screening assay of human immunodeficiency virus type 1 antibodies based on recombinant protein p24-gp41 as a fusion protein expressed in Escherichia coli.

The objective of this study was expression of a recombinant fusion protein p24-gp41 to gain a proper folding pattern of the proteins which could be recognized by specific antibodies against human immunodeficiency virus type 1 (HIV-1) for development of a reliable serodiagnostic kit. Serodiagnostic method using enzyme-linked immunosorbent assay (ELISA) with the expressed recombinant fusion protein p24-gp41 was carried out to test the sensitivity and specificity of the protein using human sera and various reference panels from Boston Biomedica Inc. (BBI). The level of the expression was determined to be 30% and the final recovery from fermentation and purification process was calculated as 80 mg/L with more than 98% purity. The developed ELISA assay was demonstrated to have 100 and 99.5% sensitivity and specificity, respectively, detecting anti-HIV-1 antibody using 900 positive and 10,000 negative human sera. The developed assay showed reliable results in comparison with other reference HIV ELISA kits using various BBI panels as well. In conclusion, the recombinant fusion protein p24-gp41 was expressed and used to develop a serodiagnostic kit for screening of the HIV-1 with high sensitivity (100%) and specificity (99.5%) which could be useful for screening large groups of blood donors.

Enzyme-Linked Immunosorbent Assay↗

PubMed2006

Children and adolescents victimized by sexual abuse in the city of Rio de Janeiro: an appraisal of cases.

Physical and/or sexual abuse, negligence, and psychological abuse against children and adolescents, constitute a socially important syndrome, demanding preventive public policies and rules for its eradication. Sexual abuse, as a troublesome occurrence, or even its mere presumption, does not regularly undergo official notification. We have examined legal investigative registers at the Instituto Médico-Legal do Rio de Janeiro - Sede set up from January to March 2000, including women, children and adolescents, with medico-legal histories suggestive of sexual assault. From a sample of 1419 cases, we selected those involving vaginal coitus or other libidinous practices, with an upper age limit of 17 years, reducing our sample to 44 subjects. 84.09% of the assaults occurred between ages 0 and 14 years. In 62.36% of the studied cases there was no mention about perpetrators. Material for laboratory researches had not been collected in 84.09% of the cases. There is any lesions in 70.45% of the sample.

Adolescent↗

PubMed2006

The frequency of occurrence and discriminatory power of compounds found in human scent across a population determined by SPME-GC/MS.

The composition of human scent collected from the hands is of interest to the medical community as a mechanism to diagnose disease and the forensic community as a means to investigate canine scent discriminations. An extensive survey of the volatile organic compounds (VOCs) identified in the headspace of hand odor samples utilizing solid phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) has been conducted to determine the constituents of the human base odor profile. Sixty-three compounds were extracted from the collected odor samples. The composition included acids, alcohols, aldehydes, hydrocarbons, esters, ketones and nitrogen-containing compounds. The majority of the compounds detected (79.4%) were present in less than one third of the individuals sampled. Spearman correlation coefficient comparisons at a match/no-match threshold of 0.9 produced a distinguish ability of 99.67% across the population.

Adolescent↗

PubMed2005

Green tea leaf extract improves lipid and glucose homeostasis in a fructose-fed insulin-resistant hamster model.

The present study evaluated the effect of green tea (Camellia sinensis L.) leaf extract on triglyceride and glucose homeostasis in a fructose-fed hypertriglyceridemic, insulin-resistant hamster model. There was a significant decrease in plasma triglyceride levels following supplementation of the green tea epigallocatechin gallate-enriched extract (42% at 150 mg/(kg day) to 62% at 300 mg/(kg day) for 4 weeks). Compared to baseline, the fructose control group at the end of the study showed elevated serum insulin and apolipoprotein B levels, and decreased serum adiponectin levels. The fructose/green tea extract group showed a reversal in all of these metabolic defects, including an improvement in glucose levels during a glucose tolerance test. Triglyceride content was also examined in various tissues and compared to the control fructose group; supplementation of the green tea extract (300 mg/kg) reduced triglyceride content in liver and heart tissues. There was molecular evidence of improved lipid and glucose homeostasis based on peroxisome proliferator-activated receptor (PPAR) protein expression. Compared to the control fructose group, supplementation of the green tea extract (300 mg/kg) significantly increased PPARalpha and PPARgamma protein expression. In summary, the data suggest that intake of the green tea extract ameliorated the fructose-induced hypertriglyceridemia and the insulin-resistant state in part through PPAR.

Animals↗

PubMed2004

Laparoscopy assists surgical decision making in infants with necrotizing enterocolitis.

BACKGROUND: Lack of specific indications for surgical intervention is not uncommon in critically ill infants with necrotizing enterocolitis (NEC). The authors hypothesized that knowledge of the extent of intestinal disease would assist in deciding the operative treatment of choice. The authors report that initial experience with laparoscopy in infants with NEC. METHODS: Prospective evaluation was done of 11 infants with a clinical diagnosis of NEC who were deteriorating despite maximal medical therapy. All underwent laparoscopy on the intensive care unit (ICU). RESULTS: Median gestational age at birth was 29 weeks (range, 24 to 34) and median weight at the time of laparoscopy was 1.2 kg (range, 0.6 to 2.9). Laparoscopy was tolerated well in all cases. NEC was excluded because of the normal intestinal appearance in 2 infants and confirmed in the remaining 9. Urgent laparotomy was avoided in 8 infants, in one of whom a laparoscopically guided ileostomy was performed. In 5 infants, a Penrose drain was inserted at laparoscopy; 3 of these did not require further surgery, and the remaining 2 underwent delayed laparotomy. Three infants, all with intestinal gangrene, died. CONCLUSIONS: Laparoscopy performed in the ICU can provide information regarding intestinal viability which can guide further surgical management. It is feasible and tolerated well even in critically ill neonates less than 1,000 g.

Enterocolitis, Necrotizing↗

PubMed2005

Effectiveness of alimemazine in controlling retching after Nissen fundoplication.

BACKGROUND: Retching, an early component of the emetic reflex, is a common and distressing symptom in children after Nissen fundoplication. Alimemazine (trimeprazine, Vallergan; Castlemead, Herts, UK) is a phenothiazine derivative histamine(1) antagonist, which anecdotally relieves the retching symptoms. MATERIAL AND METHODS: A prospective, double-blind, randomized, crossover, placebo-controlled study of 15 neurologically impaired children with retching after Nissen fundoplication over a period of 1 year (December 2002-December 2003). Patients were randomly allocated to receive 1 week each of alimemazine and placebo with crossover. A diary was maintained of retching episodes 1 week before, during, and 1 week after the trial. Dosage of alimemazine used was 0.25 mg/kg 3 times a day (maximum, 2.5 mg per dose). Statistical analysis was done using a paired Student's t test, where P value of less than .05 was considered significant. Results are presented as mean +/- SD. RESULTS: Twelve parents completed the diaries (9 open, 3 laparoscopic Nissen fundoplication). Median age of the child was 36 months (8-180 months), median duration of retching was 4.5 months (1-52 months), and mean number of retching episodes per week was 60 +/- 29.40. Mean number of retching episodes with alimemazine was 10.42 +/- 9.48 vs 47.67 +/- 27.79 with a placebo (P < .0001). No adverse effects were reported in those cases that completed the study. CONCLUSION: At low dose, alimemazine (Vallergan) is a safe and effective drug in the management of retching after Nissen fundoplication.

Antipruritics↗

PubMed2006

Outcome of antenatally diagnosed sacrococcygeal teratomas: single-center experience (1993-2004).

AIMS: Sacrococcygeal teratomas (SCTs) are the commonest neonatal tumors with an incidence of approximately 1:30,000. There are few large single-center series and even fewer describing both their antenatal and postnatal course. We report the outcome of all fetuses investigated at a tertiary fetal medicine center with this diagnosis. METHOD: Demographic details were obtained from a prospectively maintained database. Patient records were examined for additional data including antenatal and postnatal interventions. Data were described as median (range). RESULTS: Forty-one SCTs were diagnosed antenatally during the period 1993 to 2004. Twelve were excluded from subsequent analysis (single antenatal visit or attending for second opinion [n = 6] and termination of pregnancy [n = 6]). Twelve underwent fetal intervention (laser vessel ablation [n = 4], alcohol sclerosis [n = 3], cyst drainage [n = 2], amniodrainage [n = 2], vesicoamniotic shunt [n = 1]) for fetal hydrops and polyhydramnios to aid in delivery and to prevent obstructive uropathy developing in the fetus. Of these, 3 died in utero and 9 survived to be born (median gestational age, 33 weeks [27-37 weeks]). A further 3 died in the neonatal period. There are 6 long-term survivors (50%) from this group. Seventeen infants, without intervention, were born at median gestational age 38 weeks (26-40 weeks). One infant with severe cardiac anomalies died on the day of birth. All surviving infants had definitive excisional surgery at a median of 2 days (1-16 days). Current median follow-up of survivors is 39 months (8-86 months). There have been no recurrences. One child has mild constipation, and 3 are awaiting cosmetic revision of their scars. CONCLUSIONS: The overall survival of antenatally diagnosed SCT is approximately 77%, with the development of hydrops and others requiring in utero intervention carrying a poor prognosis. Otherwise, the outcome after surgical excision is excellent.

Adult↗

PubMed2005

A novel accurate amplification created restriction site method for determination of the wild type and the precore mutant hepatitis B virus variants.

The most commonly occurring hepatitis B virus (HBV) mutation is the G to A mutation at nucleotide 1896 in the precore region. The aim of this study was to develop a novel accurate amplification created restriction site (ACRS) method for determination of the TGG wild type and the TAG precore mutant HBV variants. Two conserved and consensus specific and diagnostic primers introducing BstXI and XagI cleavage sites were designed in order to determine the G1896 wild type and the A1896 precore mutant HBV variants in all HBV genotypes. The results of the ACRS method were compared with sequencing data. With the ACRS method, three different patterns could be distinguished for the wild type, the precore mutant and mixed infection HBV variants. The results of the ACRS method on 30 HBV isolates revealed the TAG precore mutant in 50% (15/30), the TGG wild type variant in 30% (9/30) and the mixed infection in 20% (6/30). The sequencing data of these samples were in agreement with the ACRS results. The ACRS method is a rapid and cost-effective technique for detecting both the TGG wild type and the TAG HBV precore mutant variants. It can be carried out for follow-up of G1896A precore mutant variant in hepatitis B virus infected subjects at routine molecular diagnostic laboratories.

Adolescent↗

PubMed2006

Performance of the automated Abbott RealTime HIV-1 assay on a genetically diverse panel of specimens from London: comparison to VERSANT HIV-1 RNA 3.0, AMPLICOR HIV-1 MONITOR v1.5, and LCx HIV RNA Quantitative assays.

Automated RNA extraction and quantitation of HIV-1 by real-time PCR offer potential advantages of efficient sample processing, improved sensitivity, expanded dynamic range and reduced contamination risk. In this study, plasma was collected from 100 HIV-1 infected patients visiting The Courtyard Clinic of St. George's Hospital in London, United Kingdom (UK). Viral loads measured using the automated Abbott RealTime HIV-1 assay (m2000sp sample preparation and m2000rt amplification and detection instruments) were compared to results obtained with Versant HIV-1 RNA 3.0 (bDNA), AMPLICOR HIV-1 MONITOR v1.5 (Monitor v1.5) and LCx HIV RNA Quantitative (LCx HIV) assays. Based on gag p24, pol integrase, and env gp41 sequences, the panel included 26 subtype A, 20 B, 27 C, 10 D, 1 CRF01_AE, 3 CRF02_AG and 13 recombinant viruses. RealTime HIV-1, bDNA, Monitor v1.5 and LCx HIV quantitated 82, 74, 82, and 83% of samples, respectively, with 82, 71, 69 and 80 of the 100 samples measured within the dynamic ranges. Viral loads were highly correlated with 99% of values within 1 log(10) copies/ml between tests. The automated m2000 system and RealTime HIV-1 assay can increase laboratory throughput, enhance overall efficiency and reduce operator-associated errors while providing reliable quantitation of genetically diverse strains of HIV-1.

Automation↗

PubMed2004

Insulin regulates hepatic apolipoprotein B production independent of the mass or activity of Akt1/PKBalpha.

Insulin is known to be a downregulator of apolipoprotein B (apoB) via the phosphatidylinositol 3-kinase (PI3K) pathway. Akt, also known as protein kinase B (PKB), is a serine/threonine kinase downstream target of PI3K. Recent studies in the fructose-fed hamster model of insulin resistance have shown that hepatic very-low-density lipoprotein (VLDL) secretion is associated with reduced phosphorylation of Akt, suggesting a potential link between Akt expression and/or activity and apoB production in hepatocytes. We hypothesized that overexpression of Akt1 downregulates apoB production. An expression vector with a constitutively active form of Akt1 was transfected in the rat hepatoma McArdle cells (McA RH-7777), McA cells stably expressing human apoB-15 and apoB-48 (15% and 48% of total apoB length), and human hepatoma HepG2. The overexpressed Akt1 was phosphorylated at Ser473 independent of acute insulin stimulation, suggesting that it was catalytically active. Despite dosage-dependent overexpression of Akt1 in both McA and HepG2 cells, neither intracellular nor secreted protein mass of intact apoB or transfected human apoB-15/apoB-48 was significantly affected by high intracellular levels of Akt1. Radiolabeling experiments also yielded no difference in the amount of newly synthesized apoB when comparing transfected and mock-transfected cells. Transfection in conjunction with high-dose insulin did not significantly decrease the secretion of either apoB-100 or apoB-48 in McA cells, or apoB-100 in HepG2 cells. HepG2 cells were more sensitive to the inhibitory effects of insulin on apoB secretion compared to McA cells, but neither model responded to Akt1. Overall, the data suggest that acute insulin-mediated inhibition of apoB may not be mediated by Akt1 and that insulin signaling molecules upstream of Akt1 may be more important in mediating control of apoB secretion.

Animals↗

PubMed2005

Increased diacylglycerol acyltransferase activity is associated with triglyceride accumulation in tissues of diet-induced insulin-resistant hyperlipidemic hamsters.

Over-accumulation of triglyceride (TG) in insulin-sensitive tissues is associated with the development of insulin resistance. We investigated whether enhanced de novo lipogenesis via diacylglycerol acyltransferase (DGAT) may contribute to the over-accumulation of TG in various tissues (liver, adipose, muscle, and intestine) using 2 well-characterized hyperlipidemic, insulin-resistant hamster models. In general, a marked increase in TG accumulation was noted in most tissues. Interestingly, the increase in TG accumulation corresponded to an increase in microsomal DGAT activity which ranged from 114% to 575% in all of the examined tissues (n = 7 per group). To delineate the mechanism for the increase in DGAT activity, we measured the expression of DGAT-1 and DGAT-2 messenger RNA by relative reverse transcriptase polymerase chain reaction (RT-PCR). In general, DGAT gene expression changed with DGAT-1 changing the most in the liver and adipose tissue, whereas DGAT-2 showed responses mainly in muscle and intestine. The increases in messenger RNA expression were not remarkable (averaging 35%; n = 4 per group) indicating that posttranscriptional mechanism(s) may play a larger role in regulating DGAT activity. In summary, the data suggest that elevated DGAT activity/expression and the subsequent increase in de novo lipogenesis could in part induce the insulin-resistant state.

Acyltransferases↗

PubMed2005

Intestinal assembly and secretion of highly dense/lipid-poor apolipoprotein B48-containing lipoprotein particles in the fasting state: evidence for induction by insulin resistance and exogenous fatty acids.

Emerging evidence suggests that overproduction of intestinally derived apolipoprotein (apo) B48-containing lipoprotein particles may be an important contributor to both fasting and postprandial dyslipidemia in insulin-resistant states. Mechanisms regulating the assembly and secretion of apoB48-containing lipoproteins are not fully understood particularly in the diabetic/insulin-resistant intestine. In the present study, we have investigated the density profile of apoB48 lipoproteins assembled in primary hamster enterocytes. Both intracellular and secreted apoB48 particles were examined in intestinal enterocytes isolated from normal or insulin-resistant fructose-fed hamsters, as well as in enterocytes treated with exogenous oleic acid. Microsomal luminal contents and culture media were analyzed by discontinuous and sequential ultracentrifugation on sucrose and KBr gradients, respectively. ApoB48 was mostly secreted on VLDL-, LDL-, and denser HDL-sized particles in the fasting state. In pulse-chase labeling experiments, nascent apoB48-containing particles initially accumulated in the microsomal lumen as HDL-sized particles, with subsequent formation of apoB48-VLDL particles, with only a minute amount of chylomicrons observed. Treatment with 720 mu mol/L of oleic acid, increased microsomal apoB48 HDL synthesis, and induced a marked shift toward lighter more buoyant particles. A marked enhancement in assembly of apoB48-containing lipoproteins was also observed in the microsomal lumen of fructose-fed hamster enterocytes, suggesting facilitated assembly and secretion of dense intestinal lipoprotein particles in insulin-resistant states. Overall, these observations suggest that a major proportion of apoB48-containing lipoprotein particles is assembled and secreted as highly dense, HDL-sized particles. The production of these small, dense, and potentially atherogenic apoB48 particles can be stimulated by increased free fatty acid flux as well as in insulin-resistant diabetes.

Animals↗

PubMed2004

Control of the alternative sigma factor sigmaE in Escherichia coli.

Signal transduction pathways that communicate information from the cell envelope to the cytoplasm of bacteria are crucial to maintain cell envelope homeostasis. In Escherichia coli, one of the key pathways that ensures the integrity of the cell envelope during stress and normal growth is controlled by the alternative sigma factor sigmaE. Recent studies have elucidated the signal transduction pathway that activates sigmaE in response to misfolded outer membrane porins. Unfolded porins trigger the degradation of the sigmaE-specific antisigma factor RseA by the sequential action of two inner membrane proteases, leading to release of sigmaE from RseA, and induction of the stress response. This mechanism of signal transduction, regulated intramembrane proteolysis, is used in transmembrane signaling pathways from bacteria to humans.

Escherichia coli↗

PubMed2006

Entry and intracellular replication of Mycobacterium tuberculosis in cultured human microvascular endothelial cells.

Establishment of pulmonary Mycobacterium tuberculosis infection requires evasion of host innate defenses. In the lung alveoli, epithelial cells naturally resist uptake by the inhaled bacilli while macrophages patrol the epithelial surface and phagocytose foreign microbes. Alveolar microvascular endothelial cells, however, have not been examined as a potential point of direct interaction with the bacilli. It has been shown with other bacterial and viral lung pathogens that the lung endothelial cells are not only a point of interaction, but a source for intracellular replication and chronic infection by the pathogen. To investigate if endothelial cells are susceptible to M. tuberculosis infection, we examined attachment, internalization, and intracellular replication of M. tuberculosis bacilli in an immortalized human lung microvascular endothelial cell line (HULEC). By 6 h post-infection, 12% of infecting bacilli were associated with the HULEC monolayer cells. This was twice the association observed following a similar infection with cells from a human foreskin microvascular endothelial cell line (HMEC-1). As measured by survival after the addition of a high extracellular concentration of the aminoglycoside amikacin, approximately one-third of the associated bacilli were internalized and unavailable to the drug in both cell lines. Using electron microscopy, large numbers of bacilli were visible in the vacuoles of HULEC cells after 48 h post-infection; the presence of bacterial septa between adjacent mycobacteria suggests intracellular replication. These in vitro findings support the hypothesis that lung endothelial cells have the potential to participate in in vivo lung infections.

Bacterial Adhesion↗

PubMed2004

A murine model for the study of immune memory in response to pneumococcal conjugate vaccination.

We developed a murine model for assessment of immunological memory and antibody-induced protection to nasopharyngeal (NP) challenges. BALB/c female mice (n = 10 mice per study parameter) were immunized with two priming doses of the licensed 7-valent pneumococcal (Pnc) conjugate vaccine and immune responses [antibody immunoglobulin G (IgG) levels, avidity and opsonophagocytic activity] were monitored for 26 weeks until IgG levels decreased to nearly baseline. A booster dose of either 2 microg conjugate or 5 microg polysaccharide vaccine was given at week 26. The ability of these two treatments to recall immune memory established by the conjugate vaccine was determined for types 4 and 14 for up to 63 days post-booster. The ability of challenge with pneumococcal type 14 to recall the immune response was also evaluated, as well as, the number of antibody secreting cells (ASC) specific to polysaccharide (Ps) 4, 6B, and 14. A higher dose of conjugate vaccine (2 microg) was necessary to elicit a significant increase in IgG levels after priming with one dose. Priming with lower doses (0.5 and 1.0 microg) only elicited modest increases in IgG levels. Recall of the immune response was found with either conjugate or Ps vaccines. NP challenge with type 14 at week 26 did not recall the immune response, although reduction in NP Pnc load was seen post-primary immunization at 5, 10 and 26 weeks. ASCs were detected in response to either conjugate or Ps booster doses. This model allows for the screening and determination of potential alternative vaccination regimens and the study of immunological markers of memory following Pnc vaccination.

Animals↗