Athymic mice of inbred strain 101/HY with a new allele at the nude locus

Research Laboratory of Experimental Biological Models, Academy of Medical Sciences of the USSR, Krasnogorsk, Moscow Region. (Presented by Academician of the Academy of Medical Sciences of the USSR N. P. Bochkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 1, pp. 76–79, January, 1992.     

Giant cell tumor of bone: radiographic changes following local excision and allograft replacement

The authors retrospectively evaluated the clinical records and radiographs obtained from 41 patients who had giant cell tumor of bone and who were treated by local resection and allograft replacement. Postoperative complications developed in 41% of the patients. However, the eventual clinical outcome was considered to be satisfactory in 85% of all cases. There were no instances of tumor recurrence, and surprisingly, postoperative arthritis was not a major problem. The major complications encountered were infection and allograft fracture; bone infection accounted for most of the clinical failures. All infections were associated with the increasing soft-tissue swelling and bone resorption detected on radiographic studies. Other radiographic parameters that were associated with an increased rate of complications included osteopenia, increased periosteal reaction, and decreased bone formation at the host-donor junction site. The clinical outcome was distinctly less favorable in those cases in which the patient had had a pathologic fracture or a previous resection, or in whom the graft was implanted at the distal radius.     

A major nucleolar protein B23 as a marker of proliferation activity of human peripheral lymphocytes

A novel monoclonal antibody (Mab) (called 3C9) against a major nucleolar phosphoprotein B23 was used to study B23 qualitative and quantitative alterations in phytohemagglutinin (PHA) -stimulated human peripheral blood lymphocytes in indirect immunofluorescence and Western blots. It was shown that lymphocyte proliferation was accompanied by gradual augmentation of nucleoli and their accumulation of the protein B23 up to 2-fold by 16 h and 40-50 fold by 72 h, as compared with the non-stimulated cells. By parallel immunolabeling with the anti-Ki-67 antibody, it was shown that the early changes of B23 amount and localization occurred before an appearance of Ki-67 protein, a well-known marker of proliferating cells. Our results evidence that antibodies against B23 might be applied for recognition of human peripheral lymphocytes at early stages of their activation for proliferation, preceding the S-phase.     

Kinetics and 28-day test–retest repeatability and reproducibility of [11C]UCB-J PET brain imaging

[¹¹C]UCB-J is a novel radioligand that binds to synaptic vesicle glycoprotein 2A (SV2A). The main objective of this study was to determine the 28-day test–retest repeatability (TRT) of quantitative [¹¹C]UCB-J brain positron emission tomography (PET) imaging in Alzheimer’s disease (AD) patients and healthy controls (HCs). Nine HCs and eight AD patients underwent two 60 min dynamic [¹¹C]UCB-J PET scans with arterial sampling with an interval of 28 days. The optimal tracer kinetic model was assessed using the Akaike criteria (AIC). Micro-/macro-parameters such as tracer delivery (K₁) and volume of distribution (V_T) were estimated using the optimal model. Data were also analysed for simplified reference tissue model (SRTM) with centrum semi-ovale (white matter) as reference region. Based on AIC, both 1T2k_V_B and 2T4k_V_B described the [¹¹C]UCB-J kinetics equally well. Analysis showed that whole-brain grey matter TRT for V_T, DVR and SRTM BP_ND were –2.2% ± 8.5, 0.4% ± 12.0 and –8.0% ± 10.2, averaged over all subjects. [¹¹C]UCB-J kinetics can be well described by a 1T2k_V_B model, and a 60 min scan duration was sufficient to obtain reliable estimates for both plasma input and reference tissue models. TRT for V_T, DVR and BP_ND was <15% (1SD) averaged over all subjects and indicates adequate quantitative repeatability of [¹¹C]UCB-J PET.     

Therapy-Induced Changes in CXCR4 Expression in Tumor Xenografts Can Be Monitored Noninvasively with N-[11C]Methyl-AMD3465 PET

Molecular Imaging and Biology - Chemokine CXCL12 and its receptor CXCR4 are constitutively overexpressed in human cancers. The CXCL12-CXCR4 signaling axis plays an important role in tumor...