Comparison of hen egg lysozyme immunoassays based on different labels

To check the concentrations of hen egg lysozyme in foodstuffs, added as a bacteriostatic agent, immunoassays based on different labels have been developed. The following detection limits (defined as non‐specific binding increased by three standard deviations) were achieved using antibody labelled with either peroxidase ¹²⁵ I or a biotin‐streptavidin system: 0–8; 0–75 and 0–13 ng/ml, respectively. Only the most sensitive lysozyme immunoassay was likely to be suitable for application to analysis of cheese because matrix interference effects mean that sample extracts need to be diluted prior to assay.     

Effect of metal ion on the radical polymerization of methyl methacrylate

The polymerization of methyl methacrylate (MMA) initiated by azoisobutyronitrile (AIBN) in the presence of various metal chlorides and water was investigated in N,N-dimethylformamide (DMF). The order of catalytic activity of the metal chlorides for the polymerization of MMA is as follows: A complex formation between poly(methyl methacrylate) (PMMA) and the metal ions was observed from the measurement of the solution viscosity of PMMA in the presence of the same metal ions in DMF.     

Modulation of large conductance calcium-activated K+ channel by membrane-delimited protein kinase and phosphatase activities

Large conductance Ca²⁺-activated K⁺ channel was identified and studied in excised inside-out membrane patches of freshly dispersed smooth muscle cells from rabbit gastric antrum. The current-voltage relationship of the single channel was linear from -80 to +80 mV of pipette voltage in which single channel conductance was 249±17.8 pS (n=19) in symmetrical concentration of K⁺ (145mM) across the patch. Activity of the channel (NPo) depended not only on cytoplasmic calcium concentration but also on membrane potential. MgATP increased NPo in a dose-dependent manner and Mg²⁺ was prerequisite for the effect. Okadaic acid (l00nM), inhibitor of protein phosphatases, increased NPo further in the presence of MgATP. Therefore, it would be concluded that activity of the calcium-activated K⁺ channel in gastric smooth muscle cells was controlled by phosphorylation state of the channel protein and the state is further modulated by membrane-delimited protein kinase and protein phosphatase activities.     

Hepatic reinnervation following orthotopic liver transplantation in man.

We have studied changes in the pattern of intrinsic hepatic innervation in sequential liver biopsies from 16 patients who underwent orthotopic liver transplantation. Seventy-one needle biopsies were used, including specimens obtained at the time of transplantation (time zero) and up to 4 years post-transplantation; five transplant hepatectomy tissue blocks removed 3-32 months after transplantation were also assessed. Paraffin sections were immunostained with anti-PGP 9.5 and anti-S-100 to identify nerve fibres. All 'time zero' biopsies contained portal nerves and all but two showed staining of parenchymal fibres. After 1 week, no subsequent biopsies contained parenchymal fibres. The disappearance of portal fibres was less rapid and showed greater variability between patients, but they had all disappeared by 6 weeks and there was no positive staining between 6 and 60 weeks. Thereafter, a minority of biopsies showed innervation of a few small portal tracts. Samples from the porta hepatis, hepatectomy specimens, and needle biopsies containing large tracts showed persistence of major nerve trunks at all stages. Abnormally large nerve bundles were seen in some of these areas. The pattern of nerve staining showed no obvious relationship to the intensity of rejection changes. Our results suggest that there is a limited, delayed capacity for regeneration of portal, but not parenchymal, fibres in the transplanted human liver. The physiological significance of this long-term parenchymal denervation in transplanted livers remains to be determined.     

Endorsement of Ellis' Irrational Beliefs as a function of age

Administered to a total of 788 children from grade 5 (N = 133), 7 (N = 193), 9 (N = 151), 11 (N = 158), and 13 (N = 153) a modification of Ellis' 11 irrational beliefs questionnaire reformulated for use with younger children. Results showed a linear decrease of percent item endorsement from younger to older children on 8 of 11 irrational ideas. Analysis of variance on the mean number of irrational ideas endorsed showed significant differences between children. Results indicated that endorsing irrational beliefs is a function of age and provided construct validity for the instrument presented here. Research and counseling uses of the scale are discussed.     

Inflammatory myofibroblastic tumour (inflammatory pseudotumour) of the breast. Clinicopathological and genetic analysis of a case with evidence for clonality.

Inflammatory myofibroblastic tumours (IMTs) were initially considered to be benign reactive processes, but cases with an unfavourable outcome have been reported. Moreover, clonal genetic alterations have recently been published in some cases, suggesting that IMT may represent a malignant neoplastic entity. This paper reports a case of IMT that developed in the mammary gland, an unusual site. The histological picture was characterized by a proliferation of spindle cells with little cellular atypia and rare mitoses, associated with a polymorphous inflammatory infiltrate. Their immunophenotype, characterized by the expression of vimentin, smooth muscle actin, and cytokeratins, corresponded to that of myofibroblasts. Cytogenetic analysis revealed the clonal nature of the lesion. The modal karyotype was 48, X, ins(2;X)(q34;p21.2p22.2), +7, del(9)(p23), +19. Including the present observation, a 9p deletion has now been found in three cases of IMT. These observations show that IMT may be a clonal neoplasm, even in sites different from deep soft tissues.     

Interdependent effect of angiotensin-converting enzyme and platelet-activating factor acetylhydrolase gene polymorphisms on the progression of immunoglobulin A nephropathy

In order to investigate the interdependent action of the insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE) gene and polymorphism in exon 11 (C1136-->T; Ala379Val) of the platelet-activating factor acetylhydrolase (PAF-AH) gene, which encodes a functional antagonist of PAF, on the progression of immunoglobulin A (IgA) nephropathy, we analysed both polymorphisms in patients with primary IgA nephropathy, who were followed-up for longer than 3 years. During the follow-up (87.3 +/- 50.0 months), the disease progressed in 38 of the 191 patients (19.9%). The D allele of the ACE gene in the absence of the T allele of the PAF-AH gene did not affect the prognosis [odds ratio (OR), 3.6; 95% confidence interval (CI), 0.8-16.4] and neither did the T allele in the absence of the D allele (OR, 3.0; 95% CI, 0.4-24.2). However, the presence of both was a significant prognostic factor (OR, 6.6; 95% CI, 1.4-31.3). After adjusting for other risk factors, the presence of both proved to be an independent risk factor (OR, 4.5; 95% CI, 1.6-12.7). These results suggest that the interdependent effects of ACE and PAF-AH polymorphisms on the progression of IgA nephropathy might be more important than the effect of the individual polymorphisms.     

Fas (APO-1/CD95) ligand and Fas expression in renal cell carcinomas: correlation with the prognostic factors

BACKGROUND AND OBJECTIVE: Fas ligand (FasL, CD95L) is a type II transmembrane protein of the tumor necrosis factor family that induces cells to send an apoptotic signal to cells expressing Fas (CD95, APO-1). It has been shown that cancers have a dysregulated expression of Fas and FasL system, conferring a survival advantage. It is important to understand FasL and Fas expression in tumors, because the growth of cancer might be controlled by Fas-mediated apoptosis. METHODS: The expressions of FasL and Fas were studied by immunohistochemical analyses in 51 cases of renal cell carcinomas and the adjacent normal renal tissues, respectively. In addition, their expressions were compared with prognostic factors, such as tumor size, nuclear grade, TNM stage, and histologic types. RESULTS: In nonneoplastic renal tissues, FasL was expressed in all nephron segments, whereas Fas also expressed in all tubules, except for glomeruli. In renal cell carcinomas, FasL protein was detected in 50 (98.0%) of 51 cases, whereas Fas expressed in 38 (74.5%) of 51 cases. In fact, the immunostaining of Fas was less intense than that in the adjacent normal segments of all cases. The staining pattern showing both high expression of FasL and low expression of Fas was found in 36 (70.6%) (P = .04) of 51 cases, most of which were Fuhrman grade 2 or 3 tumors. However, the expression pattern did not correlate statistically with the tumor size, histologic type, or clinical stage. On the other hand, most grade 4 tumors displayed high expression of both FasL and Fas (P<.001). CONCLUSION: These data indicate that high expression of FasL and low expression of Fas protein in renal cell carcinomas may play a role in evading surveillance of the immune system. In addition, the FasL and Fas expressions appear to have a therapeutic implication for high-grade tumors rather than a prognostic one.     

Differential Growth of IFN-beta-Engineered Tumor Cells in Nude and IFN Receptor-Null Mice.

The purpose of this study was to investigate the therapeutic potential of interferon-beta (IFN-beta) against tumors that resist its antiproliferative effects. Mouse fibrosarcoma cells (UV-2237m-P) and their counterparts, transfected with either IFN-beta cDNA (UV-2237m-IFN-beta) or its control vector (UV-2237m-neo), were used in the study. UV-2237m-IFN-beta cells, still expressing functional IFN receptors, were resistant to the antiproliferative effects of IFN-beta. UV-2237m-P and UV-2237m-neo cells produced progressive tumors in both nude and IFN receptor-null nude (IFNAR-/-nude) mice. In contrast, growth of UV-2237m-IFN-beta cells was significantly delayed in nude mice. UV-2237m-IFN-beta tumors from nude mice contained fewer microvessels, fewer proliferating cells, and more apoptotic cells than did UV-2237m-P and UV-2237m-neo tumors. They expressed high levels of inducible nitric oxide synthase (iNOS) and were densely infiltrated by macrophages. Incubation with macrophages from nude mice, but not those from IFNAR-/- nude mice or iNOS-null/nude mice, led to more significant killing of UV-2237m-IFN-beta cells than that of control cells, which was blocked by iNOS inhibitor N-methylarginine. Similarly, more UV-2237m-IFN-beta cells were killed when they were incubated with spleen lymphocytes from nude mice. These data indicate that IFN-beta can inhibit growth of IFN-beta-resistant tumors by T cell-independent host-mediated mechanisms, including the role of macrophages, natural killer (NK) cells, and iNOS activity.     

Mediation of in vivo glucose sensor inflammatory response via nitric oxide release

In vivo glucose sensor nitric oxide (NO) release is a means of mediating the inflammatory response that may cause sensor/tissue interactions and degraded sensor performance. The NO release (NOr) sensors were prepared by doping the outer polymeric membrane coating of previously reported needle-type electrochemical sensors with suitable lipophilic diazeniumdiolate species. The Clarke error grid correlation of sensor glycemia estimates versus blood glucose measured in Sprague-Dawley rats yielded 99.7% of the points for NOr sensors and 96.3% of points for the control within zones A and B (clinically acceptable) on Day 1, with a similar correlation for Day 3. Histological examination of the implant site demonstrated that the inflammatory response was significantly decreased for 100% of the NOr sensors at 24 h. The NOr sensors also showed a reduced run-in time of minutes versus hours for control sensors. NO evolution does increase protein nitration in tissue surrounding the sensor, which may be linked to the suppression of inflammation. This study further emphasizes the importance of NO as an electroactive species that can potentially interfere with glucose (peroxide) detection. The NOr sensor offers a viable option for in vivo glucose sensor development.