Serum iron as a tumor marker in renal cell carcinoma

To evaluate the feasibility of using serum iron as a tumor marker for renal cell carcinoma, a retrospective review of serum iron, hemoglobin, hematocrit, mean corpuscular volume and pathology in patients with renal cell carcinoma was carried out. From January 1985 to December 1989, preoperative serum iron was obtained in 82 patients; 27 had stage I, 5 stage II, 23 stage III and 27 had stage IV disease. The serum iron levels (micrograms/dl) were 81.6 +/- 33.2 in stage I, 57.8 +/- 18.9 in stage II, 59.6 +/- 34.6 in stage III and 45.6 +/- 32.7 in stage IV disease, which were significantly lower as compared with the data (114.6 +/- 38.9) of a control group. Postoperative serum iron levels were available in 31 patients following nephrectomy and all showed an increase as compared with preoperative data except 2: 1 with recurrence and the other with progression of disease. It was concluded that the serum iron level may be used as a useful tumor marker in staging and follow-up of renal cell carcinoma.

Cellular and molecular mechanisms for reduced interleukin 4 and interferon-gamma production by neonatal T cells

The mechanisms by which T lymphocytes acquire the capacity to produce interleukin 4 (IL-4) and other lymphokines during intrathymic and extrathymic development are poorly understood. To gain insight into this process, we determined the capacity of human neonatal and adult T lineage cell populations to produce IL-4 after polyclonal activation. IL-2 and interferon-gamma (IFN-gamma) production were studied in parallel, since their production by neonatal T cells is known to be similar or diminished, respectively, compared to adult T cells. Production of IL-4 by neonatal CD4+ T cells and IFN-gamma by neonatal CD4+ and CD8+ T cells was markedly lower compared with analogous adult cell populations, whereas IL-2 production was similar. Transcription of IL-4, as determined by nuclear run-on assays, and IL-4 mRNA-containing cells, as determined by in situ hybridization, were undetectable in neonatal T cells, whereas both were detectable in adult T cells. IFN-gamma transcription and IFN-gamma mRNA-containing cells were reduced in neonatal T cells compared with adult T cells. Reduced lymphokine production by neonatal T cells correlated with their lack of a CD45R- (putative memory T cell) population; cells with this surface phenotype comprised 30-40% of the adult CD4+ T cells and were highly enriched for IL-4 and IFN-gamma, but not IL-2 production. IL-4, IFN-gamma, and IL-2 mRNA expression by neonatal CD4+CD8- thymocytes was similar to that found in circulating neonatal CD4+ T cells. Taken together, these findings suggest that the extrathymic generation of memory T cells during postnatal life may result in an increased capacity for IL-4 and IFN-gamma gene expression. In addition, IFN-gamma and IL-2 mRNA were significantly more abundant than IL-4 mRNA in activated neonatal CD4+CD8- thymocytes and CD4+ T cells, as well as adult CD4+ CD45R- T cells. Therefore, the capacity of T lineage cells to express the IL-4 gene may be more restricted compared to other lymphokine genes beginning in intrathymic development. This restricted capacity appears to persist during postnatal extrathymic maturation of T cells.

Interleukin 4 expressed in situ selectively alters thymocyte development

Using a transgenic mouse model we show that increased intrathymic expression of interleukin 4 (IL-4) significantly perturbs the development of thymocytes. Transgenic double-positive (CD4+CD8+) thymocytes, which are present in dramatically reduced numbers, exhibit increased T cell receptor (TCR) expression and increased mobilization of calcium mediated by these receptors. In contrast, transgenic single-positive (CD4+CD8- and CD4-CD8+) thymocytes and peripheral T cells exhibit decreased TCR-mediated calcium mobilization. The development of CD4-CD8+ thymocytes is significantly perturbed by IL-4 expressed in vivo; only peripheral CD4+ T cells are found in significant numbers in transgenic mice, while CD4-CD8+ thymocytes are present in increased numbers, apparently because of their failure to emigrate to the periphery. In contrast to these selective effects on T cell development, no significant differences in the numbers of B cells or mast cells, or in the plasma levels of IgE and IgG1 are observed between transgenic and control mice. These observations suggest that IL-4 in vivo exerts its major effects locally rather than systemically, even when its expression is constitutively increased.

Proliferating cell nuclear antigen (PCNA) immunolocalization in paraffin sections: an index of cell proliferation with evidence of deregulated expression in some neoplasms

Proliferating cell nuclear antigen (PCNA) is a 36 kD nuclear protein associated with the cell cycle. A monoclonal antibody, PC10, that recognizes a fixation and processing resistant epitope has been used to investigate its tissue distribution. Nuclear PCNA immunoreactivity is found in the proliferative compartment of normal tissues. PCNA immunoreactivity is induced in lectin stimulated peripheral blood mononuclear cells in parallel with bromodeoxyuridine incorporation and the number of cells with PCNA immunoreactivity is reduced by induction of differentiation in HL60 cells. In non-Hodgkin's lymphomas a linear relation between Ki67 and PCNA staining was demonstrated. These data suggest that in normal tissues and lymphoid neoplasms, PCNA immunolocalization can be used as an index of cell proliferation. However, in some forms of neoplasia, including breast and gastric cancer and in vitro cell lines, the simple relation between PCNA expression and cell proliferation is lost. In some breast and pancreatic tumours there is apparent deregulation of PCNA with increased expression in tissues adjacent to the tumours. The over-expression in some tumours and in adjacent morphologically normal tissue may represent autocrine or paracrine growth factor influence on PCNA gene expression.

Homologous and heterologous enhancers modulate spatial expression but not cell-type specificity of the murine gamma F-crystallin promoter

Previous studies have shown that mouse gamma F-crystallin sequences −759 to +45, which include the core promoter and two upstream enhancer elements, contain sufficient information for directing gene expression to terminally differentiated fiber cells of the ocular lens. To investigate the role that proximal sequences of the mouse gamma F-crystallin promoter play in the developmental regulation of gene expression, we generated transgenic mice containing the lacZ gene driven by either mouse gamma F-crystallin sequences −171 to +45, which lack functional enhancers, or a hybrid hamster alpha A-/mouse gamma F-crystallin promoter, which contains the hamster alpha A-crystallin enhancer instead of operational gamma F-crystallin enhancers. In situ analysis of lacZ expression in these mice revealed that the mouse gamma F-crystallin promoter segment −171 to +45, which shows low activity in vitro, is able to direct gene expression to the fiber cells in the nucleus of the lens. However, animals expressing gamma 171-lacZ show both a lower level of expression of the lacZ gene and a narrower pattern of staining in the lens nucleus than mice expressing gamma 759-lacZ, which contains the two enhancer elements located between −392 and −278 and −226 to −123.(ABSTRACT TRUNCATED AT 250 WORDS)

Hidradenitis suppurativa: a disease of follicular epithelium, rather than apocrine glands

A retrospective study was made of the histopathology of axillary skin excised from 12 patients with hidradenitis suppurativa. In the majority of cases (10 out of 12), squamous epithelium-lined structures, in the form of cysts or sinuses were identified in the dermis. Laminated keratin was present in all these structures and half of the cysts also contained hair shafts, suggesting that they are derived from hair follicles. Only a small proportion of cases (4 out of 12) displayed inflammation in apocrine glands, and in these the inflammation was also seen around eccrine glands, hair follicles and the epithelium-lined structures. However, in cases where the epithelium of the 'cysts' was disrupted, the inflammatory infiltrate appeared to be centred around these areas. These observations suggest that the squamous epithelium-lined structures, which probably represent abnormal dilated hair follicles, are a more constant diagnostic feature in hidradenitis suppurativa than inflammation of apocrine glands which appears to be a secondary phenomenon.

New brain perfusion imaging agents based on 99mTc-bis(aminoethanethiol) complexes: stereoisomers and biodistribution

In developing new brain perfusion imaging agents, we prepared 99mTc complexes of racemic mixtures of bis(aminoethanethiol) (BAT) derivatives containing an N'-benzylpiperazinyl (BPA) side chain. Due to the presence of a chiral center, a mixture of diastereomers (syn and anti) following chelation with the 99mTc (no-carrier-added) was obtained. The neutral and lipid-soluble 99mTc-BPA-BAT (99mTc, T1/2 = 6 h) isomers were separated. The syn and anti isomers of carrier-added 99Tc-BPA-BAT (99Tc, T1/2 = 2 x 10(5) years) were also synthesized, separated, and crystallized. The X-ray crystallography of 99Tc-BPA-BAT showed the syn and anti conformations (in relationship with the central TC(=O)N2S2 core). Despite a similarity in the partition coefficients for the two isomers, the syn isomer showed a higher in vivo brain uptake and longer brain retention in rats (2.77 and 1.08% dose/organ at 2 and 15 min) than that of the corresponding anti isomer (0.57 and 0.27% dose/organ at 2 and 15 min). This information is important and should be taken into consideration when new 99mTc-labeled brain perfusion imaging agents are being designed.

Synthesis, characterization and biodistribution of neutral and lipid-soluble 99mTc-PAT-HM and 99mTc-TMR for brain imaging

Two new ligand systems for complexation with 99mTc were prepared. The two analogs of bisaminoethanethiol (BAT): N,N'-bis(2-methyl-2-mercaptopropyl)-2,2-dimethylpropylenediamin e (PAT-HM) and N,N'-bis[2-(2-ethyl-1-mercaptopropyl)] ethylenediamine (TMR), form neutral and lipid soluble complexes with 99mTc that readily penetrate the blood-brain barrier following i.v. injection into rats. Although the 99mTc chelates do not display the prolonged brain retention required for use in single photon emission computed tomographic imaging studies, the fact that each ligand forms a neutral and lipid-soluble complex of high chemical stability when coordinated with 99mTc warrants further investigation to increase the site- and organ-specificity of these agents.

Synthesis of new bis(aminoethanethiol) (BAT) derivatives: possible ligands for 99mTc brain imaging agents

In developing new brain perfusion imaging agents for single photon emission computed tomography (SPECT), five 99mTc-labeled neutral bis(aminoethanethiol) (BAT) derivatives capable of crossing the blood-brain barrier are reported. The five ligands are prepared by two versatile synthetic methods that can specifically introduce substituents on one of the carbons between two nitrogens. These ligands formed stable and neutral complexes with the reduced 99mTc, using either Sn(II) or sodium borohydride to reduce sodium [99mTc]pertechnetate. The biodistribution in rats was evaluated with [125I]iodoantipyrine, a freely diffusible tracer, as the internal reference. Compounds with a free hydroxyl group, 6 and 15, showed lower brain uptake. High initial brain uptake was observed for compounds 10 and 14, 1.28 and 2.30% dose/organ, respectively. Compounds of this type may be used as a basis for future structural modification to improve brain uptake and retention.

Metabolism and disposition of diphacinone in rats and mice

14C-diphacinone (0.2-1.5 mg/kg) was orally administered to rats and mice. Residue distribution in various tissues and radiocarbon elimination in feces and urine were determined. More than 60% of the administered radiocarbon was eliminated in feces and about 10% in urine in 4 days from mice and in 8 days from rats. The greatest amount of radioactivity in tissues of both rats and mice appeared in liver. Brain, muscle, blood, and fat had the lowest residue levels. Metabolites in feces and liver were chromatographically isolated and identified by mass spectrometry. In addition to unchanged diphacinone, four hydroxylated metabolites were identified in feces and liver. Hydroxylation occurred on either or both the indandione or phenyl rings. The positions of the hydroxy groups on the rings were not established.

N-Acetyl-beta-glucosaminidase activity in hydatidiform mole

The N-acetyl-beta-glucosaminidase activity in hydatidiform mole is two-fold higher than that in full-term placenta. Qualitatively, the enzymes from the two tissues are similar with respect to KM values and pH optima. Both enzymes also contain a new isoenzyme form detectable by polyacrylamide gel electrophoresis. However, the molar enzyme is more susceptible to heat denaturation, presumably due to the presence of a higher level of the heat-labile isoenzyme form A in this tissue. Data are also presented incicating that the placenta is not the source of the N-acetyl-beta-glucosaminidase activity in maternal serum.

beta-Glucuronidase and oestrogens in hydatidiform mole

The activity of beta-glucuronidase (beta-D-glucuronide glycuronohydrolase, EC 3.2.1.31) in placental and hydatidiform mole tissue and in sera from non-pregnant, normal and molar pregnant women was determined. The oestrogen concentrations in the two solid tissues were also assayed. Significant differences were found in the activities of the enzyme between placental and molar tissues and among the various sera. The lower activity in molar serum corresponds to a lower concentration of oestrogens in molar tissues and may be regarded as a response to the alleviation of conjugation requirements.