Insulin stimulated glucose disposal in peripheral tissues studied with microdialysis and stable isotope tracers

BACKGROUND & AIMS: Methods to study glucose kinetics in vivo in specific tissues or tissue beds in humans are often not feasible due to invasiveness or costs of equipment needed. Here we investigate whether the loss (fractional extraction) of 2H7-glucose infused via a microdialysis catheter can be used to study glucose disposal in skeletal muscle and subcutaneous adipose tissue. METHODS AND RESULTS: A perfusion period of 2 h was needed to ensure an isotopic steady state in the microdialysis catheters in skeletal muscle and adipose tissue. In six healthy volunteers the fractional extraction increased during a hyperinsulinemic euglycemic clamp in both skeletal muscle and adipose tissue. Following 48 h of starvation in the same subjects, insulin was not able to increase the fractional extraction of 2H7-glucose from the microdialysis in comparison with a baseline measurement. CONCLUSIONS: In response to insulin infusion, the fractional extraction of 2H7-glucose from a microdialysis catheter increases in skeletal muscle and subcutaneous adipose tissue and this increase is blunted during insulin resistance induced by starvation. These results validate that the fractional extraction of a glucose tracers infused via microdialysis can be used as an index of glucose disposal in peripheral tissues or tissue beds.     

Comparison of different routes of vaccination for eliciting antibody responses in the human stomach

Determination of optimal routes to induce mucosal immune responses locally in the stomach and duodenum are important steps in the development of vaccines against Helicobacter pylori infection. In this study, we immunized H. pylori-infected individuals either nasally or rectally with a model antigen, i.e. cholera toxin B subunit, and compared the immune responses after these routes with the responses after oral or intrajejunal vaccination. Specific antibody levels in serum as well as specific antibody levels and antibody-secreting cells in biopsies from antrum and duodenum were determined by ELISA and ELISPOT methods. In contrast to oral vaccination, nasal and rectal vaccination did not induce significant increases in specific antibody-secreting cells either in the antrum or duodenum. Furthermore, when analyzing the antibody levels in saponin extracted biopsies, intrajejunal vaccination was superior to both nasal and rectal vaccination in inducing antigen-specific IgA levels in the stomach. We conclude that oral vaccination is the optimal route for induction of antigen-specific IgA antibody responses in the stomach and duodenum of humans, while nasal or rectal vaccination is less suitable for this purpose.     

Special education services and school performance in a regional cohort of low-birthweight infants at age nine

Previous research has shown that low birthweight is a predictor of several adverse educational outcomes, including special educational placement, by middle school age. Most low-birthweight follow-up studies that have extended to school age have focused on very small infants-- < 1500 or < 1000 g; less is known of the school age outcomes for infants with only moderately low birthweight (1500-2000 g). This study examines the prevalence of special educational placement and the relationship of such placement to grade retention, verbal and performance scores on tests of general intelligence, reading and maths achievement scores and classroom hyperactivity among low-birthweight children. In a regional birth cohort of 1105 infants born between 1984 and 1987 and weighing 500-2000 g, 868 children were available for follow-up at age nine. Information on special education placement as well as grade retention, intelligence, academic achievement and classroom behaviour was available on 645 (74% completion rate). Nearly a third of the cohort was classified as needing special education. Special education placement followed a birthweight gradient, occurring among 29.3% of children with birthweights 1500-2000 g, among 32.5% in children 1000-1500 g and 49.4% in children < 1000 g. Among children in special education, a similar birthweight gradient was found for maths achievement and hyperactivity, but not for reading achievement or IQ scores. Among children not in special education, only maths achievement showed such a decline with birthweight. A substantial proportion of low-birthweight children, including those of moderate low birthweight, receive special education services, although the need is greatest among those with the lowest birthweights. Maths achievement declined with birthweight regardless of educational placement. The medical and social risk factors that accompany low birthweight and may account for these findings, require further study.     

Absorption and effect of the magnesium content of a mineral water in the human body

OBJECTIVE: The kinetics of magnesium (Mg) absorption, after drinking Magnesia mineral water (204 mg Mg/L), was investigated in healthy humans aged (23-60 yrs). METHODS: Serum Mg, calcium (Ca), potassium (K) and sodium (Na) content, blood hemoglobin, erythrocyte and white blood cell counts as well as urinary volume and urine Mg content were evaluated. Subjects drank 1.5 liters of Magnesia in 30 minutes; blood and the other tests were taken at 0, 2, 6, 24 and 48 hours, and after 1, 2, 3 and 4 weeks. Serum ion quotient was calculated. Serum Mg levels increased in all cases, and returned to individual normal values after 48 hrs. Subjects drank copious amounts of the mineral water only on the first two days, later they consumed one glass of mineral water at a time, totalling 1-1.5 liters daily. RESULTS: Urinary volume and its Mg content significantly increased, with individual differences in urine Mg content depending on degrees of tissue Mg deficiency. For example, two subjects, who had the same initial serum Mg levels (79 m/M/L), responded to consumption of Magnesia mineral water similarly, with comparable rise of serum Mg but with different urinary Mg excretion, one rapidly excreting Mg, while the other lost less Mg over a longer period of time. The retention of more Mg in one than the other suggests that she had a "hidden" tissue Mg deficiency, despite a serum Mg level within normal limits. No subject experienced ECG or rhythm disturbance, and blood pressure remained unchanged during the study. One patient developed diarrhea. CONCLUSION: Magnesia's high Mg (204 mg/M) and low Na (5.4 mg/L) content makes it an excellent source of Mg for patients suffering from heart problems and/or high blood pressure.     

Photochemically enhanced gene delivery of EGF receptor-targeted DNA polyplexes

Epidermal growth factor receptor (EGFR) targeted DNA polyplexes, containing polyethylenimine (PEI) conjugated with EGF protein as cell-binding ligand for endocytosis and polyethylene glycol (PEG) for masking the polyplex surface charge, mediated a 3- to 30-fold higher luciferase gene expression in HUH7, HepG2 and A431 cell transfections than analogous untargeted PEG-PEI polyplexes. Transfection levels can be further enhanced by treatment of cells with amphiphilic photosensitizers followed by illumination. In this process photosensitizers localized in membranes of endocytic vesicles are activated by light, resulting in the destruction of endocytic membrane structures and releasing co-endocytosed polyplexes into the cell cytosol. Photochemical enhanced gene expression was observed in all cell lines, with the magnitude of enhancement depending on the particular PEI polyplex formulation and cell line, ranging between 2- and 600-fold. Importantly, improved gene transfer retained EGF receptor specificity, as demonstrated by comparison with ligand-free polyplexes and by receptor antibody or ligand competition experiments. These results suggest that this combined procedure enables a dual mode of targeting polyplexes: biological targeting via EGFR interaction, combined with physical targeting with light to direct a photochemical delivery of therapeutic genes to a desired location.     

Psychometric and utility-based measures of health status of asthmatic patients with different disease control level

OBJECTIVE: To explore the relationship between asthma control level and health-related QOL (HR-QOL), and to understand the role of various psychometric and utility-based methods in studying this relationship. METHODS: Two hundred and twenty-eight consecutive adult outpatients and inpatients at four sites participated in the study. Physicians identified the level of disease control according to the Global Initiative for Asthma (GINA) classification system. Patients filled in three different HR-QOL questionnaires (EuroQol 5-D [EQ-5D], Short-Form 36-item health survey [SF-36], and St George's Respiratory Questionnaire [SGRQ]) and a direct time trade-off question. The Short Form-6D (SF-6D) was used to derive utility values from SF-36 data. RESULTS: All patient-reported evaluation methods could discriminate between patients with different disease control levels, and both generic and disease-specific instruments strongly correlated to each other. The magnitude of differences in HR-QOL between groups with different disease control levels was clinically meaningful. All three HR-QOL measures reflected a relationship between disease control level and HR-QOL, but the actual pattern of the relationship depended on the instrument used. Utilities gained from the EQ-5D index, compared with the SF-6D index, had higher values in the patient group with the best disease control and lower values in the patient group with poor disease control. CONCLUSION: When choosing an instrument to measure the health status of asthmatic patients in clinical studies, the severity range of the study population should be considered. Researchers might prefer to use the EQ-5D in asthma patients with severe disease or poor disease control and the SF-6D in patients with mild disease or good disease control.     

NY-ESO-1 protein formulated in ISCOMATRIX adjuvant is a potent anticancer vaccine inducing both humoral and CD8+ t-cell-mediated immunity and protection against NY-ESO-1+ tumors.

NY-ESO-1 is a 180 amino-acid human tumor antigen expressed by many different tumor types and belongs to the family of "cancer-testis" antigens. In humans, NY-ESO-1 is one of the most immunogenic tumor antigens and NY-ESO-1 peptides have been shown to induce NY-ESO-1-specific CD8(+) CTLs capable of altering the natural course of NY-ESO-1-expressing tumors in cancer patients. Here we describe the preclinical immunogenicity and efficacy of NY-ESO-1 protein formulated with the ISCOMATRIX adjuvant (NY-ESO-1 vaccine). In vitro, the NY-ESO-1 vaccine was readily taken up by human monocyte-derived dendritic cells, and on maturation, these human monocyte-derived dendritic cells efficiently cross-presented HLA-A2-restricted epitopes to NY-ESO-1-specific CD8(+) T cells. In addition, epitopes of NY-ESO-1 protein were also presented on MHC class II molecules to NY-ESO-1-specific CD4(+) T cells. The NY-ESO-1 vaccine induced strong NY-ESO-1-specific IFN-gamma and IgG2a responses in C57BL/6 mice. Furthermore, the NY-ESO-1 vaccine induced NY-ESO-1-specific CD8(+) CTLs in HLA-A2 transgenic mice that were capable of lysing human HLA-A2(+) NY-ESO-1(+) tumor cells. Finally, C57BL/6 mice, immunized with the NY-ESO-1 vaccine, were protected against challenge with a B16 melanoma cell line expressing NY-ESO-1. These data illustrate that the NY-ESO-1 vaccine represents a potent therapeutic anticancer vaccine.     

Serum semicarbazide-sensitive amine oxidase (SSAO) activity correlates with VEGF in non-small-cell lung cancer patients

Semicarbazide-sensitive amine oxidase (SSAO) is an enzyme associated with vascular systems in mammals. SSAO catalyzes the deamination of primary monoamines and has been suggested to be a risk factor in vascular disorders, e.g., diabetic vascular complications. The primary aim of the present study was to investigate if serum SSAO activity is associated with clinical parameters in non-small cell lung cancer (NSCLC) patients. Secondary aims were to investigate if there is a correlation between SSAO activity and the angiogenic factors vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF).Thirty-three patients donated 231 serum samples. Detectable levels of bFGF, VEGF, and SSAO were observed in all patients. Serum SSAO activity was not statistically associated with survival (p = 0.35). A highly significant statistical correlation was found between SSAO activity and VEGF (p < 0.0001). No significant correlation between SSAO and bFGF was observed.We conclude that SSAO was not associated with survival in patients with NSCLC. However, a strong correlation between serum SSAO activity and the angiogenic factor VEGF was found that might implicate new aspects of the mechanisms controlling angiogenesis.     

Therapy for mycosis fungoides

Opinion statement Treatment of mycosis fungoides (MF) is indicated to reduce symptoms, improve clinical appearance, prevent secondary complications, and prevent progression of disease, all of which may have an impact on survival. Treatment of MF includes topical and systemic therapies, which can be administered alone or in combination. Psoralen and ultraviolet A radiation is effective in early-stage MF, inducing complete remissions in most patients. Psoralen and ultraviolet A radiation may also be combined with low doses of interferon (IFN)-a to treat stage I/II disease. However, early aggressive therapy with radiation and chemotherapy does not improve the prognosis. Local radiotherapy or total skin electron beam irradiation has been used with success to control advanced skin disease. Extracorporeal photopheresis may also be used successfully, but it is not generally available. Once the disease becomes refractory to topical therapy, IFN-a single-agent or combination chemotherapy may be administered, but the duration of response is often less than 1 year and ultimately all patients will relapse and become refractory. Among chemotherapeutic agents, pentostatin, gemcitabine, and liposomal doxorubicin seem to be particularly effective. Response rates after combined modality therapy with total skin electron beam irradiation and chemotherapy/IFN-a appear similar to response rates of chemotherapy alone. Therefore, there is a great need for the further development of novel emerging treatment modalities, such as retinoids (ie, bexarotene) and immunotherapeutic agents (ie, cytokines, tumor vaccines, and monoclonal antibodies), all of which appear to have significant therapeutic potential in patients with MF. Biologically based therapies may reduce the need for genotoxic therapies, such as cytostatics and radiotherapy.     

Strong associations between gene function and codon usage

The association between codon usage and gene function was analyzed in the complete genomes of Eschericia coli, Bacillus subtilis, Lactococcus lactis and Campylobacter jejuni, using the functional annotation provided by NCBI. Two distinctly different ways of quantifying codon usage were used in the analysis. By using contingency tables it was found that for most amino acids a highly significant association with gene function exists for all species, indicating that codon usage at the level of individual amino acids is generally closely coordinated with gene function. By computing the effective number of codons in the annotated genes and comparing the median values in groups of different gene functions it was shown for all species that codon bias gene by gene also differs.