A novel CD44v6 targeting antibody fragment with improved tumor-to-blood ratio.

The chimeric monoclonal antibody U36 (cMAb U36) recognizes the CD44v6 antigen. Its potential as a radioimmunotargeting agent, as well as its safety, has been shown in previous studies in head and neck cancer patients. However, intact MAbs have long circulation time in the blood and tumor targeting may also be hampered due to the slow and incomplete diffusion into solid tumors. In comparison, smaller monovalent Fab' and divalent F(ab')2 fragments are expected to exhibit shorter circulating half-lives, better tumor penetration and are thus more likely to yield better imaging results. In this study, novel F(ab')2 and Fab' fragments from cMAb U36 were radiolabeled with 125I and the characteristics of the conjugates in vitro were examined. The biodistribution of the conjugates were then evaluated in nude mice bearing CD44v6-expressing xenograft tumors. Furthermore, the penetration depth and distribution in tumor tissue was assessed by autoradiography in selected tumor samples. The in vitro experiments showed that the conjugates were stable and had intact affinity to CD44v6. The biodistribution study demonstrated superior tumor-to-blood ratio for the novel cMAb U36 fragment 125I-F(ab')2 compared with both the intact MAb and the monovalent fragment form. Autoradiography also revealed better tumor penetration for 125I-F(ab')2. This study demonstrates that the use of antibody fragments may improve radioimmunotargeting and possibly improve the management of head and neck malignancies.

Herschel detects a massive dust reservoir in supernova 1987A.

We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of about 220 times the luminosity of the Sun. The intensity and spectral energy distribution of the emission suggest a dust mass of about 0.4 to 0.7 times the mass of the Sun. The radiation must originate from the supernova ejecta and requires the efficient precipitation of all refractory material into dust. Our observations imply that supernovae can produce the large dust masses detected in young galaxies at very high redshifts.

Descriptions of functioning and health and relations to a gross motor classification in adults with cerebral palsy.

PURPOSE: The aim of this study was to describe functioning and health, and explore the use of the Gross Motor Function Classification System (GMFCS) in an adult population with cerebral palsy (CP). METHODS: From a cohort of 199 persons, 48 persons were selected for structured interviews and functional assessments regarding activities of daily living, motor function, range of motion, pain and general health. RESULTS: A third of the population had deteriorated in function from adolescence to adulthood according to the GMFCS. The majority were independent in personal ADL, but many of those were dependent in instrumental ADL. Motor function scores reflected problems in walking ability, and limited ROM and pain were common in all functional levels. General health was lower than in a general population. GMFCS seems valid for classifying adults with CP since it is correlated with instruments measuring motor function and ADL in terms of dependence. CONCLUSION: Decreased functional ability and secondary musculoskeletal problems are common in adults with CP and general health can be associated with those problems. It is important to further explore health aspects and relations between health status and self-perceived health. The GMFCS is a useful tool, especially for comparisons throughout the life span, but in order to use in an adult population further development is needed.

Inhibition of the CD28-CD80 co-stimulation signal by a CD28-binding affibody ligand developed by combinatorial protein engineering.

CD28 is one of the key molecules for co-stimulatory signalling in T cells. Here, novel ligands (affibodies) showing selective binding to human CD28 (hCD28) have been selected by phage display technology from a protein library constructed through combinatorial mutagenesis of a 58-residue three-helix bundle domain derived from staphylococcal protein A. Analysis of selected affibodies showed a marked sequence homology and biosensor analyses showed that all investigated affibodies bound to hCD28 with micromolar affinities (KD). No cross-reactivity towards the related protein human CTLA-4 could be observed. This lack of cross-reactivity to hCTLA-4 suggests that the recognition site on hCD28 for the affibodies resides outside the conserved MYPPPYY motif. The apparent binding affinity for hCD28 could be improved through fusion to an Fc fragment fusion partner, resulting in a divalent presentation of the affibody ligand. For the majority of selected anti-CD28 affibodies, in co-culture experiments involving Jurkat T-cells and CHO cell lines transfected to express human CD80 (hCD80) or LFA-3 (hLFA-3) on the cell surface, respectively, pre-incubation of Jurkat cells with affibodies resulted in inhibition of IL-2 production when they were co-cultured with CHO (hCD80+) cells, but not with CHO (hLFA-3+) cells. For one affibody variant denoted Z(CD28:5) a clear concentration-dependent inhibition was seen, indicating that this affibody binds hCD28 and specifically interferes in the interaction between hCD28 and hCD80.

A gas-phase biosensor for environmental monitoring of formic acid: laboratory and field validation.

In order to encourage more exposure measurements to be performed, a formic acid gas-phase biosensor has been developed for this purpose. In the present paper, an enzyme based biosensor has been validated with respect to analyte selectivity and on-site use. To ensure that the sampler developed measures the compound of interest the biosensor was exposed to three near structural homologues to formic acid, i.e. acetic acid, methanol and formaldehyde. These vapours were generated with and without formic acid and the only compound that was found to have an effect on the performance of the biosensor, albeit a small one, was acetic acid. The field test was performed in a factory using formic acid-containing glue for glulam products. In parallel to the measurements with the biosensor a well defined reference method was used for sampling and analysing formic acid. It was found that the biosensor worked satisfactorily in this environment when used in a stationary position. It was also shown that the biosensor could determine formic acid vapour concentrations down to 0.03 mg m(-3).

GM-CSF safety and effects in the management of advanced/refractory multiple myeloma patients: a phase I trial.

PURPOSE: Some limitations of effective therapy in multiple myeloma include the low growth fraction of the malignant plasma cells, multi-drug resistance, and the presence of other concurrent diseases in this patient population. A phase I study was conducted to evaluate the toxicity of granulocyte macrophage colony stimulating factor (GM-CSF) in myeloma patients as well as the potential effect on the plasma cell labeling index (PCLI). Relapsed patients with multiple myeloma were eligible. METHODS: The first phase of this trial assessed the toxicity (including the effect on disease progression) of escalating doses (125-500 microg/m2 SC, days 1-5) of GM-CSF, and the effects of this cytokine on PCLI. Patients whose PCLI doubled and increased to > or = 1.7% were treated with chemotherapy including cyclophosphamide, vincristine, prednisone, and GM-CSF. Twenty-two patients were enrolled. RESULTS: The toxicity of GM-CSF was mild, and no dose-limiting side effects were seen. Twenty-five percent of patients (5/20) achieved the target PCLI, and 4/5 proceeded to receive chemotherapy. No relationship of GM-CSF dose to increases of the PCLI was noted. All patients who received chemotherapy responded. CONCLUSIONS: GM-CSF has acceptable toxicity in patients with multiple myeloma and produced increases of PCLI in selected individuals. Further studies of GM-CSF alone or in combination with chemotherapy are indicated.

Specific metal-ion binding sites in a model of the P4-P6 triple-helical domain of a group I intron.

Divalent metal ions play a crucial role in RNA structure and catalysis. Phosphorothioate substitution and manganese rescue experiments can reveal phosphate oxygens interacting specifically with magnesium ions essential for structure and/or activity. In this study, phosphorothioate interference experiments in combination with structural sensitive circular dichroism spectroscopy have been used to probe molecular interactions underlying an important RNA structural motif. We have studied a synthetic model of the P4-P6 triple-helical domain in the bacteriophage T4 nrdB group I intron, which has a core sequence analogous to the Tetrahymena ribozyme. Rp and Sp sulfur substitutions were introduced into two adjacent nucleotides positioned at the 3' end of helix P6 (U452) and in the joining region J6/7 (U453). The effects of sulfur substitution on triple helix formation in the presence of different ratios of magnesium and manganese were studied by the use of difference circular dichroism spectroscopy. The results show that the pro-Sp oxygen of U452 acts as a ligand for a structurally important magnesium ion, whereas no such effect is seen for the pro-Rp oxygen of U452. The importance of the pro-Rp and pro-Sp oxygens of U453 is less clear, because addition of manganese could not significantly restore the triple-helical interactions within the isolated substituted model systems. The interpretation is that U453 is so sensitive to structural disturbance that any change at this position hinders the proper formation of the triple helix.

Sweet taste preference as a risk factor for alcohol dependence.

OBJECTIVE: Previous research has found that alcoholics have a greater preference for sweet solutions than comparison subjects. This study tested the hypothesis that preference for sweet solutions is a marker for alcoholism risk. METHOD: A total of 122 nonalcoholic subjects (59 men) participated. Fifty-eight subjects had a paternal history of alcoholism, and 64 did not. Each subject rated a series of sucrose solutions for intensity of sweetness and degree of preference. RESULTS: Subjects were able to rate accurately the relative intensity of sweetness in the sucrose solutions. Both subjects with and those without a paternal history of alcoholism preferred a 0.42-M sucrose solution, irrespective of gender. CONCLUSIONS: This study failed to support the hypothesis that sweet preference is a marker of alcoholism risk. The sweet preference observed previously among alcoholics may be a consequence of chronic alcohol consumption or other factors associated with heavy drinking.

Multivariate evaluation of factors influencing the performance of a formic acid biosensor for use in air monitoring.

A formic acid biosensor for air monitoring has been evaluated using chemometric methods. Using experimental design eleven factors that could influence the performance of the biosensor were examined. The response matrices consisted of six parameters (steady state currents at three different formic acid concentrations and response rates during changes in formic acid concentrations) describing the performance of the biosensor. The data were evaluated using a combination of principal component analysis (PCA) and multiple linear regression (MLR). To confirm the conclusions from the PCA-MLR partial least squares (PLS) was also used. The most important factor for the biosensor performance was found to be the enzyme concentration. Using the information from the chemometric analyses the optimum operation conditions for the biosensor were determined. The steady state currents were increased by 18-30% and the initial two response rates increased by 47-89% compared with a biosensor that had not been optimised.

Effects of propofol on substance P-induced relaxation in isolated human omental arteries and veins.

To elucidate if an effect of propofol on endothelium-dependent relaxation could contribute to propofol-induced vasodilation, smooth muscle relaxation of isolated human omental artery and vein segments precontracted by endothelin-1 were measured. Substance P induced a concentration-dependent relaxation (mean +/- SEM) in both artery (63 +/-8.4% of precontraction, n = 9) and vein (60+/-11%, n = 7). The relaxation was enhanced by 10(-6) M propofol (artery, 72+/-9.5%, n = 9; vein, 81+/-12%, n = 7) but not affected by 10(-7), 10(-5) and 10(-4) M propofol. In the presence of Nomega-nitro-L-arginine methyl ester (nitric oxide synthase inhibitor), 10(-6) M propofol still enhanced the substance P-induced relaxation in arteries but not veins, whereas 10(-4) M propofol inhibited the relaxation in both arteries (rightward shift of the concentration-response curve) and veins (28+/-7.5%, n = 8). In the presence of potassium chloride (to prevent hyperpolarization), the enhancement of substance P-induced relaxation by 10(-6) M propofol was abolished in both arteries and veins whereas 10(-5) and 10(-4) M propofol reduced the relaxation in arteries (38+/-13% at 10(-5) M, n = 6; 30+/-11% at 10(-4) M, n = 6) but not in veins. These results demonstrate that propofol, at lower, clinically relevant concentrations, promotes endothelium-dependent relaxation mediated via hyperpolarization in human omental arteries and via both nitric oxide and hyperpolarization in human omental veins.

Effects of propofol on desipramine-sensitive [3H]-noradrenaline uptake kinetics in rat femoral artery.

BACKGROUND: The intravenous anaesthetic propofol inhibits the neuronal uptake of noradrenaline (uptake1) from the vascular sympathetic neuromuscular junction, resulting in an enhancement of the sympathetic neurotransmission. This could be important for maintenance of blood pressure during propofol anaesthesia. The aim of the present study was to determine how propofol influences the kinetics of uptake1. METHODS: Isolated segments of rat femoral arteries were incubated with [3H]-noradrenaline in the presence or absence of propofol and the radioactivity taken up was measured in a scintillation counter. The uptake1 inhibitor, desipramine, was used to delineate the specific neuronal uptake. RESULTS: Desipramine and 10 microM propofol significantly reduced the uptake in segments incubated with 0.1 microM [3H]-noradrenaline. Propofol at 1 microM and 100 microM did not affect the uptake. Non-linear regression analysis of specific uptake yielded Km 0.50 microM, Vmax 1.6 pmol mg(-1) 15 min(-1) and Hill coefficient 1.1. Propofol (1-10 microM) increased the Km value and propofol (10-100 microM) increased the Vmax value concentration-dependently, while the Hill coefficient was not affected. CONCLUSION: Propofol seems to have a biphasic effect on the uptake of noradrenaline in the vascular sympathetic neuromuscular junction. At lower propofol concentrations there is a decrease in the affinity of the noradrenaline transporters. The resulting uptake inhibition is counteracted at higher propofol concentrations by an increase in the efficacy of the uptake.

Phase II trial of liposomal doxorubicin (Doxil) in advanced soft tissue sarcomas.

PURPOSE: To assess the objective response rate, toxicity experienced, progression-free survival, and overall survival of patients with previously untreated advanced soft tissue sarcomas treated with a liposomal doxorubicin formulation (Doxil). METHODS: Patients with metastatic or recurrent soft tissue sarcoma who had received no prior chemotherapy for advanced disease were treated with liposomal doxorubicin (Doxil) according to a two stage accrual design. Doxil was administered at 50 mg/m2 every 4 weeks. A total of 15 patients were treated and are evaluable for response and toxicity. RESULTS: The male/female ratio was 7/8, the median age was 60 years (34-75) and the ECOG performance status was 0-1 in >90% of patients. Leiomyosarcoma (7/15) and malignant fibrous histiocytoma (2/15) were the most common histologic diagnoses. No objective responses were observed in the 15 evaluable patients. No lethal toxicity occurred. Grade 3-4 leukopenia or neutropenia were reported in 3/15 (20%) patients. Grade 3 mucositis or hand-foot syndrome occurred in 2/15 (13%) and 1/15 (7%) patients respectively and seemed more severe in older patients. The median time to progression was 1.9 months (range 0.9-6.2). Twelve patients have now died. The Kaplan-Meier estimate of median overall survival is 12.3 months. As called for in the study design, accrual was terminated because no responses were obtained in the first 15 patients. CONCLUSION: Though well-tolerated, Doxil given according to this dose and schedule to patients with advanced soft tissue sarcoma had no significant therapeutic activity. A correlation between older age and skin/mucosal toxicity of Doxil is suggested in this study but needs confirmation. Future investigations of Doxil in soft tissue sarcomas should use a different schedule and dose.

A method to study apoptosis in eosinophils by flow cytometry.

The aim of this study was to develop a simple flow cytometric procedure to study eosinophil apoptosis. Eosinophils were isolated from the peripheral blood of healthy, non-allergic individuals and then cultured in basal culture medium. The cells were examined after 24, 48 and 72 h for forward- and side scatter (FS-SSC) pattern, staining with FDA, PI, and anti-CD95, and light microscopic appearance. After culture for >24 h, two populations with different FS-SSC-patterns appeared, referred to as A and B. Population A consisted of living, FDA-positive eosinophils. The eosinophils in population B showed a lower FS scatter than those in population A and a staining pattern with PI indicating the presence of hypodiploid DNA. Anti-CD95 demonstrated a significant staining of the eosinophils in population B, which increased after 2 days in culture. The cells were sorted using a FACS-Scan cell sorter and by Annexin V-coated magnetic beads to permit separate analyses of PI-staining pattern, DNA electrophoresis, and light microscopic examination of the cells in population B. The present study suggest that it is possible to discriminate between apoptotic and living eosinophils using the FS-SSC pattern and the PI-staining pattern obtained by flow cytometry.

Increased levels of S-100 protein after cardiac surgery with cardiopulmonary bypass and general surgery in children.

The aim of this study was to evaluate changes in concentrations of the neurospecific protein S-100 in relation to cardiac surgery with cardiopulmonary bypass (CPB) and noncardiac general surgery in children below 3 years of age. Seventeen children underwent surgery for congenital heart disease and all survived without clinical signs of neurological complications. Samples for plasma concentrations of S-100 in these patients were taken on three occasions in connection with surgery: before the start of surgery, after CPB and finally 16-20 h after CPB. In the noncardiac group of 31 children, S-100 concentrations were measured on two occasions: before surgery and during surgery. In both groups, a significant increase in S-100 concentrations was observed during surgery, although the increase in the CPB group was significantly higher than in the noncardiac group. The CPB group included four children with Down's syndrome who had higher mean S-100 concentrations on all sampling occasions compared to the remaining patients. The peak S-100 concentrations after cardiac surgery were related to the duration of CPB, the time from the termination of CPB to the first post-CPB sample, as well as mean arterial pressure and cerebral arteriovenous lactate difference during rewarming. All the children studied (Down's patients excluded) had age-dependent plasma concentrations of S-100 measured before surgery. It can be concluded that CPB initiates a marked but transient release of S-100 into the systemic circulation during open heart surgery in children who are not developing clinical signs of neurological sequelae.

The predictive power of combined neuropsychological measures for attention-deficit/hyperactivity disorder in children.

The present study explores the predictive power of seven neuropsychological assessment tools used in combination in classifying children with attention-deficit/hyperactivity disorder (ADHD). Twenty-one ADHD boys and 22 community control children participated. Group differences were significant on the continuous performance test only; however, battery analysis did increase overall predictive power, which was moderate. This study highlights the difficulty in identifying consistent mean differences on tests of frontal/executive functioning across studies, as well as the need to assess the predictive validity of these tests in classifying children with ADHD. The study suggests that these tests may provide greater predictive validity when used in combination. Inconsistencies in the literature are discussed, with consideration of research methodology, the heterogeneity of the ADHD population, and comorbid diagnoses.

T-cell adoptive immunotherapy of metastatic renal cell carcinoma.

OBJECTIVES: To determine the feasibility and toxicity of the adoptive transfer of ex vivo-activated T lymphocytes that have been sensitized to autologous tumor vaccine in vivo. METHODS: Twenty patients with extensive metastatic renal cell carcinoma received systemic adoptive immunotherapy with autologous T cells in the absence of conjunctional interleukin-2 (IL-2) administration. Patients were vaccinated intradermally with irradiated autologous tumor cells and granulocyte-macrophage colony-stimulating factor as an adjuvant to stimulate an immune response. Inguinal lymph nodes draining the vaccine site were surgically removed, and the cells were stimulated with staphylococcal enterotoxin A followed by expansion in 60 IU/mL IL-2, and in some cases additionally stimulated with anti-CD3 monoclonal antibody and IL-2, to obtain a large number of cells. RESULTS: The staphylococcal enterotoxin A/IL-2 activation induced vigorous proliferation of T cells (median expansion 26-fold) that were a mixture of CD4 and CD8 T lymphocytes. Activated cells were infused intravenously at doses ranging from 2x10(9) to 9.5x10(10). There was minimal toxicity consisting of grade 1 or 2 fever and nausea, and the entire treatment was delivered as outpatient therapy. One patient had a partial response, one had a mixed response, and 8 had stable disease lasting at least 5 months. CONCLUSIONS: Adoptive transfer of ex vivo-activated, tumor vaccine-primed lymph node cells is feasible and is associated with minimal toxicity when used alone. These results warrant further study in a Phase II trial.

Jugular bulb temperature compared with non-invasive temperatures and cerebral arteriovenous oxygen saturation differences during open heart surgery.

Limited information is available about the correlation between cerebral temperature and routine temperature measurements during cardiopulmonary bypass in infants. Nasopharyngeal, tympanic membrane and rectal temperatures were compared with jugular bulb temperature in ten infants operated on with moderate or deep hypothermia. The cerebral arteriovenous saturation differences were correlated with the temperatures at the four measurement sites. The jugular bulb and nasopharyngeal temperatures showed the most rapid response during cooling and rewarming. The tympanic temperature response varied in an unpredictable way. Rectal temperature, which was the target for rewarming, lagged behind during both cooling and rewarming. Overwarming at the end of cardiopulmonary bypass, seen as jugular bulb and nasopharyngeal temperatures exceeding 38 degrees C, was common after deep hypothermia. A high correlation was found between the cerebral arteriovenous oxygen saturation differences and the jugular bulb temperature (r = 0.81) and the nasopharyngeal and the tympanic temperature (r = 0.79), whereas the correlation with rectal temperature was weaker (0.66).

Intraoperative glucose administration influences respiratory quotient during paediatric anaesthesia.

BACKGROUND: Oxidation of carbohydrates and fat yields respiratory quotients (RQ) of 1.0 and 0.7 respectively. Maintained or increased blood glucose concentrations are usually seen during paediatric anaesthesia and surgery even without glucose administration. The aim of the present study was to evaluate whether an intraoperative glucose infusion influences the RQ as an indication of a different metabolic preference in comparison to a glucose-free fluid regime. METHODS: Eighteen children between 0.5 and 24 months of age were studied during anaesthesia with controlled ventilation, oxygen in air, isoflurane, thiopentone, atracurium and fentanyl. Oxygen consumption and carbon dioxide production were measured using indirect calorimetry All children received Ringer acetate as needed; in addition, nine children were given glucose 10%, 3 ml.kg-1.h-1, corresponding to 300 mg.kg-1.h-1. Blood samples for analyses of glucose, lactate, free fatty acids and ketones were taken before and during surgery. RESULTS: RQ was significantly higher in the children given glucose 0.92 +/- 0.08, compared to 0.81 +/- 0.06 in the children without glucose (P < 0.01). Oxygen consumption tended to be higher, although not significantly so, in patients without glucose infusion. Energy expenditure was 1.70 +/- 0.29 kcal.kg-1.h-1, without significant group differences. Higher blood glucose concentrations during surgery were found in the children given glucose. CONCLUSIONS: Our results indicate a higher glucose oxidation rate in patients given glucose during surgery.