Strong antibody reaction against glycosphingolipids injected in liposome-embedded forms in beta3GN-T5 knockout mice

It is known that mutant mice of the beta-1,3-N-acetylglucosaminyltransferase gene (beta3Gn-T5) respond well to T-cell dependent and independent antigens. Here, we examined the effectiveness of anti-ganglioside antibody generation by immunization of beta3Gn-T5 mutant mice with liposome-embedded glycosphingolipids such as GD1a and GT1b. Consequently, the mutant mice showed a more efficient generation of anti-GD1a or anti-GT1b antibodies than wild-type mice in an enzyme-linked immunosorbent assay using sera during immunization. Thus, the beta3Gn-T5 deficient mutant mice proved more responsive than wild-type mice to not only protein antigens, but also to carbohydrates in glycolipids. Furthermore, about 50% of monoclonal antibodies generated using splenocytes of the immunized mutant mice were of the IgG class. Besides general high responsiveness to proteins and glycolipids, it could be expected that the mutant mice of beta3Gn-T5 would be useful in the generation of monoclonal antibodies towards lacto-/neolacto-series glycolipids, since these mutants lack lacto-/neolacto-series glycolipids. In fact, they showed a good serum response in immuno-fluorescence assay with cultured living cells when immunized by glycolipids extracted from ovarian cancer cell lines. These results suggested that beta3Gn-T5 mutant mice are useful for the generation of anti-glycolipid antigens with lacto-/neolacto-core structures expressed in cancer cells.     

Cardiac β-adrenergic receptor density and myocardial systolic function in the remote noninfarcted region after prior myocardial infarction with left ventricular remodelling

Purpose

After myocardial infarction (MI), left ventricular (LV) remodelling is observed in noninfarcted LV myocardium. LV remodelling is closely associated with systolic heart failure. Since myocardial dysfunction is related to the downregulation of cardiac postsynaptic beta-adrenergic receptors (β-AR), we hypothesized that a reduction in β-AR density may be manifested in the remote noninfarcted region and such reduction may be related to myocardial systolic dysfunction. Accordingly, we assessed β-AR density with a focus on the remote noninfarcted region.

Methods

Cardiac PET was performed in 15 patients with a prior MI and 10 age-matched healthy controls using ¹¹C-CGP 12177, a radioligand for β-receptors. The maximum number of available specific ¹¹C-CGP 12177 binding sites per gram of tissue was calculated in regions of interest using an established graphical method. LV regional systolic function was assessed based on peak systolic myocardial strain on the LV wall in the longitudinal direction using two-dimensional ultrasound speckle tracking imaging. LV volumes and LV ejection fraction (EF) were also measured.

Results

The LV end-diastolic volume index was significantly larger in patients than in controls (67.8?±?16.9 vs. 49.1?±?12.3?ml/m², p?p?p?Conclusion In the remote noninfarcted region in patients, β-AR downregulation was observed, which was related to deterioration of local myocardial systolic function.     

Changes in catecholamine and immunoglobulin during anesthesia for cardiac surgery--a comparison of valve replacement and aorto-coronary bypass surgery

During a period of extracorporeal circulation, which represents a massive invasion for the body, the patient is in a state of controlled shock. In this study, we examined changes in catecholamines and immunoglobulins in patients grouped according to whether they underwent valve replacement or aorto-coronary bypass surgery. Anesthesia was induced with fentanyl, and cardiopulmonary bypass in all patients was carried out using a bubble-type heart-lung machine. The epinephrine and norepinephrine levels increased during the procedures, but those patients having aorto-coronary bypass surgery showed milder rises than valve replacement patients. IgA, IgG and IgM all dropped as well, but the change in IgG was the greatest, and the decreases were more marked in valve replacement patients than in aorto-coronary bypass patients. It was concluded that, since reactions were different according to the disorder present and were reflected in the variations in catecholamine and immunoglobulin levels, great care is necessary when the patient is removed from the heart-lung machine.     

Vestibular symptoms in acute hemispheric strokes

Journal of Neurology - A prospective study focused on whether vestibular symptoms are seen in acute hemispheric strokes, and if so, the frequency and lateralization of causative lesions on MRI....     

Recurrent thymoma in patients with myasthenia gravis

One hundred sixty-six patients underwent operation for myasthenia gravis between 1977 and 1989. Thirty-eight patients had associated thymoma, registering stages I (n = 17), II (n = 9), III (n = 11), and IVa (n = 1) according to the classification of Masaoka and colleagues. Extended thymectomy was performed on 128 patients without thymoma; thymothymectomy, with resection of the anterior mediastinal fat and tissues adherent to the tumor, was performed in all patients with thymoma. There were no instances of early or late death. Neuromuscular function improved, and clinical myasthenic symptoms stabilized in almost all patients except 2 patients in stage III and 1 patient in stage IVa, who had an exacerbation of the myasthenic symptoms associated with recurrence of thymoma. All the recurrent tumors were on the pleura and could be resected. The suspected cause of recurrence is either dissemination of tumor cells as a result of operative manipulation or undetected disseminated foci that existed at the time of the first operation. The resections of the recurrent invasive thymomas localized on the pleura were easily performed and improved the myasthenic symptoms.     

Identification of genes linked to gefitinib treatment in prostate cancer cell lines with or without resistance to androgen: a clue to application of gefitinib to hormone-resistant prostate cancer

Understanding the molecular action of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, might allow us to perform more effective therapies for hormone-independent advanced prostate cancer. A DNA microarray study was undertaken to comprehensively analyze the alteration of levels of 1,081 genes after gefitinib treatment in androgen-independent PC3 and DU145 cells and androgen-dependent LNCaP cells. The proliferation of PC3, DU145 and LNCaP cells was significantly inhibited by 50.2%, 83.8% and 55.2%, respectively, 6 days after 10 microM gefitinib administration. Of the above 1,081 genes, we identified 23, 13 and 33 genes with significantly different expression in PC3, DU145 and LNCaP cells, respectively, 24 h after 10 microM-gefitinib exposure. Among the identified genes, only Quiescin Q6, a negative cell cycle regulator, was increased after gefitinib treatment in all three cell lines regardless of gefitinib sensitivity. Except for Quiescin Q6, there were no overlapping genes between PC3 and DU145 cells. However, levels of several oncogenes or proliferation-related genes were changed after gefitinib treatment in the 2 androgen-independent cell lines. We also identified 7 unique genes [glycyl-tRNA synthetase, interferon, alpha-inducible protein, stratifin, nuclear factor of kappa light polypeptide gene enhancer in B-cells 1, dual specificity phosphatase 9, guanine nucleotide binding protein (G protein) beta polypeptide 2, neural retina leucine zipper] whose levels were altered exclusively after gefitinib administration in gefitinib-resistant PC3 and LNCaP cells, but not in DU145 cells, suggesting that these 7 genes could be targets for overcoming gefitinib resistance. Collectively, our molecular profiling data will serve as a framework for understanding the molecular action of gefitinib for prostate cancer.     

Functional CD4+T cell subsets defined by expression of CD45RC and NTA260 antigens and age-associated polarization in murine lupus

Using two mAb, one specific to the alternative exon 6-dependentepitope of CD45 molecules(JH6.2) and one a natural thymocytotoxicautoantibody (NTA) with an unknown reactive epitope (NTA260),we subdivided splenic CD4⁺ T cells from 2-month-old BALB/c miceinto five phenotypically distinct subsets. CD45RC⁺NTA260^–(SI) cells were phenotypically analogous to CD4⁺ T cells predominatingin newborn mice and produced a significant amount of IL-2, butnot so IL-4, IL-10 or IFN- when stimulated with immobilizedanti-CD3 mAb in vitro. They appeared to consist mainly of naiveT_hP cells. The CD45RC⁺;NTA260⁺ (S II) subset also produced IL-2,but not other cytokines; however, the IL-2 levels produced weremuch higher than seen with the S I subset, thereby suggestingthe predominance of further maturated T_hP cells. The D45RC^–NTA260⁺(S III) subset mainly produced IL-4, IL-10, IFN- and less IL-2,and contained memory cells that helped the secondary antibodyresponse to a recall antigen, and hence contained T_h2 and probablya mixture of T_h0 and T_h1 cells. The CD45RC^–NTA260^–(S IV) subset was a poor responder to the immobilized anti-CD3mAb. The CD45RC^brightNTA260^dull(S V) subset consisted of a smallnumber of cells that were phenotypically analogous to activatedCD4⁺ T cells. While an age-associated decrease in the proportionof S I and less markedly in S II and in turn increase in S IIIsubsets of CD4⁺ T cells occurred in normal BALB/c mice, autoimmunedisease-prone (NZBxNZW)F₁ mice showed a marked age-associateddecrease in the proportion of not only S I, II but also IIIsubsets. As aged (NZBxNZW)F₁ mice carry CD4⁺ T helper cellsfor IgG anti-DNA antibody production, such age-associated polarizationto the S IV subset appears to be critical in the pathogeneslsof autoimmune disease in these mice.     

Deposition of extracellular matrix on silicone intraocular lens implants in rabbits

Purpose: To examine the deposition of extracellullar matrix on silicone intraocular lenses (IOLs) implanted experimentally into rabbit eyes by electron microscopy and to determine the immunolocalization of extracellular matrix components, including collagen types and cellular fibronectin, on these IOLs. Methods: We performed phacoemulsification and aspiration of the crystalline lens and implanted a foldable silicone IOL in the capsular bag of one eye of each of 26 adult albino rabbits under general anesthesia. After 8 weeks the animals were killed and the eyes were enucleated. The silicone IOLs were processed for electron microscopy and for immunohistochemical detection of collagen types I, III, and IV and cellular fibronectin. Results: Electron microscopy revealed deposition of a presumed cell matrix complex on the optic portion of all silicone IOLs, as well as the adhesion of presumed macrophages and foreign-body giant cells. Cellular deposits showed immunoreactivity for cellular fibronectin. Fibrous or membranous deposits exhibited immunoreactivity for cellular fibronectin and collagen types I and III. A few type IV collagen-immunoreactive deposits were also seen. Conclusion: Deposits of extracellular matrix components were observed on silicone IOLs. These deposits may form the scaffolding for the adhesion and proliferation of cells. These matrix components appeared to be the products of cells adhering to the surfaces of IOLs, including lens epithelial cells, macrophages and foreign-body giant cells, indicating that the process of granulation was incomplete.