The treatment of malignant lymphoma has improved over the past 20 years, but the majority of patients are not cured. New modalities using targeted therapy based on new information in molecular ...biology and immunology hold promise for better outcomes with less toxicity. We review data on the use of radiolabeled monoclonal antibodies directed against the CD20 antigen on malignant B cells. We discuss the major radionuclides available, iodine 131 ((131)I), tositumomab, and yttrium 90 ((90)Y) ibritumomab tiuxetan (Zevalin; IDEC Pharmaceuticals, San Diego, CA) and present data on new approaches in labeling antibodies that have facilitated their use. Clinical trial data with the yttrium-labeled antibodies are discussed. The use of dosimetry as a means for predicting toxicity is discussed, and the questions of long-term toxicity (late effects) are addressed. These targeted approaches to the treatment of malignancy, and lymphoma in particular, hold great promise.
Abstract
We present high-statistic data on charged-pion emission from Au + Au collisions at
$$\sqrt{s_{\mathrm{NN}}} = 2.4~\hbox {GeV}$$
s
NN
=
2.4
GeV
(corresponding to
$$E_{beam} = 1.23~\hbox {A ...GeV}$$
E
beam
=
1.23
A GeV
) in four centrality classes in the range 0–40% of the most central collisions. The data are analyzed as a function of transverse momentum, transverse mass, rapidity, and polar angle. Pion multiplicity per participating nucleon decreases moderately with increasing centrality. The polar angular distributions are found to be non-isotropic even for the most central event class. Our results on pion multiplicity fit well into the general trend of the available world data, but undershoot by
$$2.5~\sigma $$
2.5
σ
data from the FOPI experiment measured at slightly lower beam energy. We compare our data to state-of-the-art transport model calculations (PHSD, IQMD, PHQMD, GiBUU and SMASH) and find substantial differences between the measurement and the results of these calculations.
At energies below sNN≈2.55GeV, strange quarks cannot be produced in binary nucleon-nucleon collisions because of the higher production threshold of the lightest hadrons carrying strangeness. Hence, ...the investigation of sub-threshold strangeness production in heavy-ion collisions is one of the most promising probes, to access the properties of the created system, as the missing energy must be provided by the latter one. For the first time, a nearly complete set of strange particles has been reconstructed in the 40% most central Au+Au collisions at sNN=2.42GeV. The data sample includes multi-differential representations of charged and neutral particles containing strangeness (K±, Ks0, ϕ, Λ). To achieve a better understanding of strangeness production the properties of the short-lived resonances have to be investigated. The first steps in this direction are presented here, including the reconstruction of baryon resonances using a new iterative technique, comparison to microscopic transport model calculations and interpretation of the pion transverse momentum distribution.
Post-therapy whole-body I-131 images were compared to 5 mCi pretherapy diagnostic studies in 39 cases of well-differentiated thyroid carcinoma treated with I-131 to evaluate the utility of this ...procedure for the detection of residual thyroid tissue and functioning metastases. The post-therapy studies were performed immediately before hospital discharge, when the patient's whole-body retained dose had just fallen below 30 mCi. The mean therapeutic dose given was 121 mCi, and the mean interval between administration of the therapy dose and imaging was 2.4 days. In 18 cases (46.2%), the post-therapy images demonstrated either additional findings, such as unsuspected cervical node or pulmonary uptake, or more accurate localization of abnormalities seen on the diagnostic study. In 6 additional cases (15.4%), questionable new findings were noted. Although the precise implications of these additional findings are uncertain at present, they may have a significant effect on future patient management and follow-up. Therefore, the authors recommend that post-therapy imaging be included in the post-therapy evaluation of these patients. In addition, these findings would also suggest reevaluation of the advisability of using 1-2 mCi doses of I-131 for diagnostic whole-body imaging.
The purpose of this investigation was to develop and evaluate a new and rapid miniaturized chromatography system that would accurately assess the radiochemical purity of 99mTc-tetrofosmin without the ...problems of solvent ratios and time requirements associated with the manufacturer's recommended procedure.
The migration of the radiochemical components of 99mTc-tetrofosmin was evaluated using various chromatography media with ethyl acetate as the solvent. After optimization of the miniaturized system, radiochemical purity assessments were performed simultaneously on 23 99mTc-tetrofosmin preparations using both recommended and miniaturized chromatography systems.
A miniaturized chromatography system consisting of Whatman 1 chromatography paper with ethyl acetate was developed for the radiochemical purity assessment of 99mTc-tetrofosmin. Radiochemical purity results for 99mTc-tetrofosmin preparations were similar with both recommended and miniaturized chromatography methods, with a mean difference of 1.5% +/- 1.2% (s.d.). Differences in radiochemical purity results between the two chromatography systems were less than 2% (20 of 23 evaluations) with most preparations.
Radiochemical purity results for 99mTc-tetrofosmin preparations were similar with both the manufacturer's recommended chromatography and miniaturized chromatography systems. The miniaturized chromatography system is easier to use, and the time required to perform radiochemical purity assessments is substantially reduced.
Members of the actinomycetes produce 1D-1-O-(2-N-acetyl-l-cysteinylamino-2-deoxy-α-d-glucopyranosyl)-myo-inositol or mycothiol 1 as principal low molecular mass thiol. Chemical synthesis of a ...biosynthetic precursor of mycothiol, the pseudodisaccharide 1D-1-O-(2-amino-2-deoxy-α-d-glucopyranosyl)-myo-inositol 13 was achieved by the following steps: (1) Enantioselective synthesis gave the glycosyl acceptors (−)-2,3,4,5,6-penta-O-acetyl-d-myo-inositol D-7 and the corresponding l-isomer L-7. (2) Condensation of D-7 and L-7 with the glycosyl donor 3,4,6-tri-O-acetyl-2-deoxy-2-(2,4-dinitrophenylamino)-α-d-glucopyranosylbromide afforded the corresponding α and β anomeric products, which could be resolved by silica gel chromatography. (3) Deprotection of these by hydrolysis using an anion exchange resin gave 1D- and 1L-1-O-(2-amino-2-deoxy-α-d-glucopyranosyl)-myo-inositol 13 and 15 and the corresponding β-coupled anomers 14 and 16. Only 13, and to a much lesser extent 15, were used by enzymes present in an ammonium sulphate fraction of a cellfree extract of Mycobacterium smegmatis for the enzymatic synthesis of mycothiol. In the absence of acetyl-SCoA, the immediate biosynthetic precursor of 1, desacetylmycothiol, was the major product.
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