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Background: Since the onset of the SARS-CoV-2 pandemic in late 2019, many studies suggest that actual infection rates may far exceed reported cases. Therefore, this study provides a comprehensive overview of anti-SARS-CoV-2 antibody measurements and their significance in epidemiological surveillance, especially regarding the true extent of SARS-CoV-2 infections, allowing more detailed insights into the dynamics of the pandemic. Methods: Antibodies were measured using the Elecsys® Anti-SARS-CoV-2 assay for the nucleocapsid (N) protein and the SARS-CoV-2 IgG (sCOVG) assay for the spike (S) protein. A total of 25197 specimens from University Hospital Heidelberg were analyzed between May 2020 and December 2023, with 16957 samples measured for both antibodies, 2756 for anti-N only, and 5484 for anti-S only.For the epidemiological tracing of the SARS-CoV-2 incidence we analyzed changes in the anti-N positivity rate and anti-S positivity rate within our tertiary hospital setting across consecutive quarters. Results: Anti-N measurements allowed for a retrospective analysis of SARS-CoV-2 epidemiological developments, revealing significant changes (p

Introduction: The hybrid magnetic resonance linear accelerator (MRL) has the potential to test novel concepts in breast cancer patients such as daily MR-guided real-time plan adaptation. Before starting clinical trials, preparatory studies for example of the MR-dependent electron stream effect (ESE) are necessary. Material and Methods: To prospectively investigate the ESE, data from 11 patients treated with partial breast irradiation (PBI) at the 1.5 T MRL were evaluated. A bolus was placed on the chin and in vivo dosimetry results were compared with the dose simulated by the treatment planning system (TPS). The same measurements were carried out for three patients treated at a conventional linac. Toxicity and cosmesis were evaluated. Results: Median doses measured and simulated on top/ underneath the bolus were 1.91 / 0.62 Gy and 2.82 / 0.63 Gy, respectively. Median differences between calculations and measurements were 0.8 Gy and 0.1 Gy. At the conventional linac, median measured doses on top/ underneath the bolus were 0.98 and 1.37 Gy. No acute toxicity exceeding grade 2 was recorded. Cosmesis was good or excellent and patient reported outcome measures were mostly scored as none or mild. Conclusion: The dose due to the ESE is low, correctly predicted by the TPS and effectively minimized by a bolus.

Background: The biochemical analysis of high-sensitivity cardiac troponins (hs-cTn) from peripheral blood specimens has been established as biomarker for myocardial injury. Independently of myocardial injury, increased serum hs-cTn concentrations have been described in patients with myopathies. The relevance and frequency of noncardiac hs-cTn elevations in spinal cord injury (SCI) is unknown. Our study aimed to 1) determine the frequency of increased hs-cTn concentrations of supposedly noncardiac origin above the 99th percentile (upper reference limit, URL) in an unselected SCI population and 2) compare the two protagonist analytes cTnT and cTnI with respect to these noncardiac elevations., Methods: In this monocentric, cross-sectional study, we sampled blood from n = 30 SCI subjects without cardiac symptoms to test for hs-cTnT and hs-cTnI serum concentrations., Results: 18/30 (60%) of SCI subjects showed increased hs-cTnT concentrations above the URL of 14 ng/l (p < 0.001). In 4 subjects (22.2%) concentrations were >50 ng/l. Moreover, 3 of these four subjects fulfilled the 6-h troponin dynamics criterion for acute myocardial injury in serial hs-cTnT testing. In contrast, no subject demonstrated increased hs-cTnI concentrations according to the URL of 40 ng/l. 6-h troponin dynamics were also unremarkable for hs-cTnI testing., Conclusions: SCI subjects frequently have increased hs-cTnT concentrations without clinical and hs-cTnI evidence of myocardial injury. Clinicians must be aware of cTnT "skeletal muscle false-positives" in SCI, which applies to elevated baseline cTnT concentrations and troponin dynamics in serial measurements. In case of diagnostic uncertainty, simultaneous analysis of cTnI might be helpful., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Seroconversion after COVID-19 vaccination is impaired in kidney transplant recipients. Emerging variants of concern such as the B.1.617.2 (delta) and the B.1.1.529 (omicron) variants pose an increasing threat to these patients. In this observational cohort study, we measured anti-S1 IgG, surrogate neutralizing, and anti-receptor-binding domain antibodies three weeks after a third mRNA vaccine dose in 49 kidney transplant recipients and compared results to 25 age-matched healthy controls. In addition, vaccine-induced neutralization of SARS-CoV-2 wild-type, the B.1.617.2 (delta), and the B.1.1.529 (omicron) variants was assessed using a live-virus assay. After a third vaccine dose, anti-S1 IgG, surrogate neutralizing, and anti-receptor-binding domain antibodies were significantly lower in kidney transplant recipients compared to healthy controls. Only 29/49 (59%) sera of kidney transplant recipients contained neutralizing antibodies against the SARS-CoV-2 wild-type or the B.1.617.2 (delta) variant and neutralization titers were significantly reduced compared to healthy controls (p < 0.001). Vaccine-induced cross-neutralization of the B.1.1.529 (omicron) variants was detectable in 15/35 (43%) kidney transplant recipients with seropositivity for anti-S1 IgG, surrogate neutralizing, and/or anti-RBD antibodies. Neutralization of the B.1.1.529 (omicron) variants was significantly reduced compared to neutralization of SARS-CoV-2 wild-type or the B.1.617.2 (delta) variant for both, kidney transplant recipients and healthy controls (p < .001 for all)., (© 2022 The Authors. American Journal of Transplantation published by Wiley Periodicals LLC on behalf of The American Society of Transplantation and the American Society of Transplant Surgeons.)

There is much controversy about the potential impact of spinal cord injury (SCI) on brain anatomy and function, which is mirrored in the substantial divergence of findings between animal models and human imaging studies. Given recent advances in quantitative magnetic resonance imaging (MRI) we sought to tackle the unresolved question about the link between the presumed injury associated volume differences and underlying brain tissue property changes in a cohort of chronic complete SCI patients. Using the established computational anatomy methods of voxel-based morphometry (VBM) and voxel-based quantification (VBQ), we performed statistical analyses on grey and white matter volumes as well as on parameter maps indicative for myelin, iron, and free tissue water content in the brain of complete SCI patients (n = 14) and healthy individuals (n = 14). Our regionally unbiased white matter analysis showed a significant volume reduction of the dorsal aspect at the junction between the most rostral part of the spinal cord and the medulla oblongata consistent with Wallerian degeneration of proprioceptive axons in the dorsal column tracts in SCI subjects. This observation strongly correlated with spinal cord atrophy assessed by quantification of the spinal cord cross-sectional area at the cervical level C2/3. These findings suggest that Wallerian degeneration of the dorsal column tracts represents a main contributor to the observed spinal cord atrophy, which is highly consistent with preclinical histological evidence of remote changes in the central nervous system secondary to SCI. Structural changes in other brain regions representing remote changes in the course of chronic SCI could neither be confirmed by conventional VBM nor by VBQ analysis. Whether and how MRI based brain morphometry and brain tissue property analysis will inform clinical decision making and clinical trial outcomes in spinal cord medicine remains to be determined., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Grafting of cell-seeded alginate capillary hydrogels into a spinal cord lesion site provides an axonal bridge while physically directing regenerating axonal growth in a linear pattern. However, without an additional growth stimulus, bridging axons fail to extend into the distal host spinal cord. Here we examined whether a combinatory strategy would support regeneration of descending axons across a cervical (C5) lateral hemisection lesion in the rat spinal cord. Following spinal cord transections, Schwann cell (SC)-seeded alginate hydrogels were grafted to the lesion site and AAV5 expressing brain-derived neurotrophic factor (BDNF) under control of a tetracycline-regulated promoter was injected caudally. In addition, we examined whether SC injection into the caudal spinal parenchyma would further enhance regeneration of descending axons to re-enter the host spinal cord. Our data show that both serotonergic and descending axons traced by biotinylated dextran amine (BDA) extend throughout the scaffolds. The number of regenerating axons is significantly increased when caudal BDNF expression is activated and transient BDNF delivery is able to sustain axons after gene expression is switched off. Descending axons are confined to the caudal graft/host interface even with continuous BDNF expression for 8weeks. Only with a caudal injection of SCs, a pathway facilitating axonal regeneration through the host/graft interface is generated allowing axons to successfully re-enter the caudal spinal cord., Statement of Significance: Recovery from spinal cord injury is poor due to the limited regeneration observed in the adult mammalian central nervous system. Biomaterials, cell transplantation and growth factors that can guide axons across a lesion site, provide a cellular substrate, stimulate axon growth and have shown some promise in increasing the growth distance of regenerating axons. In the present study, we combined an alginate biomaterial with linear channels with transplantation of Schwann cells within and beyond the lesion site and injection of a regulatable vector for the transient expression of brain-derived neurotrophic factor (BDNF). Our data show that only with the full combination axons extend across the lesion site and that expression of BDNF beyond 4weeks does not further increase the number of regenerating axons., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Appropriate target reinnervation and functional recovery after spinal cord injury depend on longitudinally directed regrowth of injured axons. Anisotropic alginate-based capillary hydrogels (ACH) support peripheral nervous system derived axon growth, which is accompanied by glial supporting cell migration into the ACH. The aim of the present study was to analyze central nervous system (CNS) derived (entorhinal cortex, spinal cord slice cultures) axon regrowth into ACH containing linearly aligned capillaries of defined capillary sizes without and with gelatin constituent. Anisotropic ACH were prepared by ionotropic gel formation using Ba(2+), Cu(2+), Sr(2+), or Zn(2+) ions resulting in gels with average capillary diameters of 11, 13, 29, and 89μm, respectively. Postnatal rat entorhinal cortex or spinal cord slice cultures were placed on top of 500μm thick ACH. Seven days later axon growth and astroglial migration into the ACH were determined. Axon density within capillaries correlated positively with increasing capillary diameters, whereas longitudinally oriented axon outgrowth diminished with increasing capillary diameter. Axons growing into the hydrogels were always accompanied by astrocytes strongly suggesting that respective cells are required to mediate CNS axon elongation into ACH. Overall, midsize capillary diameter ACH appeared to be the best compromise between axon density and orientation. Taken together, ACH promote CNS axon ingrowth, which is determined by the capillary diameter and migration of slice culture derived astroglia into the hydrogel., Statement of Significance: Biomaterials are investigated as therapeutic tools to bridge irreversible lesions following traumatic spinal cord injury. The goal is to develop biomaterials, which promote longitudinally oriented regeneration of as many injured axons as possible as prerequisite for substantial functional recovery. Optimal parameters of the biomaterial have yet to be defined. In the present study we show that increasing capillary diameters within such hydrogels enhanced central nervous system axon regeneration at the expense of longitudinal orientation. Axon ingrowth into the hydrogels was only observed in the presence of glial supporting cells, namely astrocytes. This suggests that alginate-based hydrogels need to be colonized with respective cells in order to facilitate axon ingrowth., (Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Despite recent progress in enhancing axonal growth in the injured spinal cord, the guidance of regenerating axons across an extended lesion site remains a major challenge. To determine whether regenerating axons can be guided in rostrocaudal direction, we implanted 2mm long alginate-based anisotropic capillary hydrogels seeded with bone marrow stromal cells (BMSCs) expressing brain-derived neurotrophic factor (BDNF) or green fluorescent protein (GFP) as control into a C5 hemisection lesion of the rat spinal cord. Four weeks post-lesion, numerous BMSCs survived inside the scaffold channels, accompanied by macrophages, Schwann cells and blood vessels. Quantification of axons growing into channels demonstrated 3-4 times more axons in hydrogels seeded with BMSCs expressing BDNF (BMSC-BDNF) compared to control cells. The number of anterogradely traced axons extending through the entire length of the scaffold was also significantly higher in scaffolds with BMSC-BDNF. Increasing the channel diameters from 41μm to 64μm did not lead to significant differences in the number of regenerating axons. Lesions filled with BMSC-BDNF without hydrogels exhibited a random axon orientation, whereas axons were oriented parallel to the hydrogel channel walls. Thus, alginate-based scaffolds with an anisotropic capillary structure are able to physically guide regenerating axons., Statement of Significance: After injury, regenerating axons have to extend across the lesion site in the injured spinal cord to reestablish lost neuronal connections. While cell grafting and growth factor delivery can promote growth of injured axons, without proper guidance, axons rarely extend across the lesion site. Here, we show that alginate biomaterials with linear channels that are filled with cells expressing the growth-promoting neurotrophin BDNF promote linear axon extension throughout the channels after transplantation to the injured rat spinal cord. Animals that received the same cells but no alginate guidance structure did not show linear axonal growth and axons did not cross the lesion site. Thus, alginate-based scaffolds with a capillary structure are able to physically guide regenerating axons., (Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The loss of oligodendroglia and demyelination contributes to the lack of functional recovery after spinal cord injury. The transplantation of adult neural progenitor cells (NPCs) might be a promising strategy to replace oligodendroglia lost after injury, however only a very small proportion of grafted NPCs differentiate into oligodendroglia. The present study aimed to investigate whether co-transplantation of subventricular zone-derived NPCs with bone marrow stromal cells (BMSCs) will enhance oligodendroglial differentiation of NPCs. In vitro, oligodendroglial differentiation was strongly enhanced by co-cultivation of NPCs with BMSCs or BMSC-conditioned medium. For in vivo experiments, adult Fischer 344 rats underwent cervical dorsal funiculus transections, immediately followed by grafting of 5-bromo-2'-deoxyuridine (BrdU) pre-labeled syngeneic NPCs mixed with BMSCs isolated from adult bone marrow. Six weeks post-injury and grafting, BMSC-containing grafts filled the lesion cavity but did not enhance oligodendroglial differentiation of co-grafted NPCs. The failure of BMSCs to induce oligodendroglial differentiation in vivo coincided with a rapid upregulation of bone morphogenetic protein 2/4 (BMP2/4) around the injury site and in vitro data demonstrated that BMP2/4 can override the oligodendrogenic effects of BMSCs. Moreover, blocking BMP activity can rescue the effect of BMSCs on NPCs. Thus, neutralization of BMP or BMP signaling might be required to allow for BMSC-induced oligodendroglial differentiation of grafted NPCs in the injured spinal cord., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Substantial recovery of function following peripheral and central nervous system (CNS) injury critically depends on longitudinally directed axon regeneration across the injury site, which requires a mechanical guidance providing scaffold. We have previously shown that anisotropic alginate-based hydrogels with a defined capillary diameter (25 μm), which form via a self-organizing process driven by unidirectional diffusion of divalent cations into sodium alginate sols, promoted longitudinally oriented elongation of CNS axons in vitro and in vivo. In the present study the influence of various capillary diameters and the incorporation of gelatin to promote directed axon outgrowth and Schwann cell migration were assessed in a dorsal root ganglion outgrowth assay in vitro. Superimposing an alginate sol with Cu(2+), Sr(2+), or Zn(2+) ion containing solutions allowed the creation of hydrogels with capillaries 18, 25 and 55 μm in diameter, respectively. Axon outgrowth and Schwann cell migration were analyzed in terms of axon length/density and Schwann cell density within the capillary structures. Axon ingrowth into capillary hydrogels, which was always accompanied by Schwann cells, was enhanced with increasing capillary diameter. The incorporation of gelatin did not influence overall axon density, but promoted the length of axon outgrowth within the hydrogels. The longitudinal orientation of axons decreased in wider capillaries, which suggests that medium-sized capillaries are the optimal substrate to elicit substantial axon growth and longitudinal orientation after axon injury., (Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

This study assessed the relation of proliferation, inhibition of apoptosis, and the p53 tumor suppressor protein expression in clear renal cell carcinoma (RCC). Archival pathological specimens from 43 patients treated for RCC were obtained. Median follow-up for the patients was 52 months (range 2.5 months to 178 months). Immunostaining of paraffin tissue sections was carried out for four different markers: a) Ki-67, a marker for cellular proliferation; b) p53/DO7, c) p53/pAb240, antibodies for the p53 protein; and d) bcl-2, a marker for inhibition of apoptosis (programmed cell death). One thousand cells were counted per slide at 400x magnification. Staining of >/=10% of cells was considered positive and <10% negative. Fisher exact contingency tables were used for correlation between markers, tumor grade and stage. A significant correlation was found between Ki-67 and p53 immunoreactivity samples, P=0.0001. Interestingly, a significant association was found if Ki-67 and bcl-2 scores were combined and correlated with p53, P=0.009. Results showed no correlation between any of the immunohistochemical markers and grade or stage. In addition, Kaplan-Meier survival curves demonstrated no significant difference between patients' tumors that was scored immunoreactive negative vs. positive for Ki-67, p53, or bcl-2. This study indicates that p53 expression correlates with proliferation, and inhibition of programmed cell death in RCC.

In the present study, we show that endothelial-like cells (ELCs) can develop from human CD14-positive mononuclear cells (CD14 cells) in the presence of angiogenic growth factors. The CD14 cells became loosely adherent within 24 h of culture and subsequently underwent a distinct process of morphological transformation to caudated or oval cells with eccentric nuclei. After 1 week in culture the cells showed a clear expression of endothelial cell markers, including von Willebrand factor (vWF), CD144 (VE-cadherin), CD105 (endoglin), acetylated low-density lipoprotein (AC-LDL)-receptor, CD36 (thrombospondin receptor), FLT-1, which is vascular endothelial cell growth factor (VEGF) receptor-1, and, to a weaker extent, KDR (VEGF receptor-2). Furthermore, in these cells structures resembling Weibel-Palade bodies at different storage stages were identified by electron microscopy, and upon culturing on three-dimensional fibrin gels the cells build network-like structures. In addition, cell proliferation and vWF expression was stimulated by VEGF, and the endothelial cell adhesion molecules CD54 (ICAM-1), and CD106 (VCAM-1) became transiently inducible by tumor necrosis factor-alpha (TNF-alpha). In contrast, the dendritic markers CD1a, and CD83 were not expressed to any significant extent. The expression of CD68, CD80 (B7-1), CD86 (B7-2), HLA-DR and CD36 may also suggest that ELCs might be related to macrophages, sinus lining or microvascular endothelial cells. Taken together, our observations indicate that ELCs can differentiate from cells of the monocytic lineage, suggesting a closer relationship between the monocyte/macrophage- and the endothelial cell systems than previously supposed.

We performed a retrospective analysis of potential prognostic markers in 260 patients with surgically resected stage I and II non small-cell lung cancer (NSCLC) with a minimum 5-year follow-up. Cox proportional hazard models and Wilcoxon tests were employed to analyze the effect of patient characteristics on survival and disease-free survival (DFS). In the univariate analysis, the following were significant predictors of shorter overall survival: N-stage (N1 vs N0) (p<0.001); T-stage (T2 vs T1) (p<0.001); antigen A (loss vs presence) (p<0.01); cough (present vs absent) (p=0.01); bcl-2 expression (positive vs negative) (p=0.03); age (>63.5 vs <63.5) (p=0.03); mucin (positive vs negative) (p<0.03). The following were significant predictors of shorter DFS: N-stage (p<0.001); T-stage (p=0.001); loss of antigen A (p=0.01); mucin expression (p<0.01); cough (p=0.02); Ki-67 expression (p=0.02) and negative bcl-2 expression (p=0.03). Analysis of survival difference for histologic subtype, degree of differentiation, aneuploidy, %S-phase, codon 12 K-ras mutation, and immunohistochemistry staining for Lewisy, p53, Rb, microvessel count, HER2, E-cadherin and neuroendocrine markers did not reach statistical significance. In multivariate analysis, the following predicted for shorter overall survival: N-stage (p<0.01), antigen A (p=0.01), age (p<0.01), and bcl-2 (p=0.05); and for DFS, N-stage (p<0.01), antigen A (p<0.01), Ki-67 (p=0.03), mucin (p=0.04) and T-stage (p=0.05). Of all the clinical-pathological, proliferative, and biological markers studied, only a few carried independent prognostic significance.

Tumor angiogenesis is essential for tumor growth and metastasis, and intratumoral microvessel density correlates with prognosis in breast carcinoma. Yet, how intratumoral microvessel density correlates with tumor cell and intratumoral endothelial cell proliferation remains incompletely understood. To this end, we stained 57 formalin-fixed, paraffin-embedded breast carcinomas with antibody MIB1 to determine tumor cell Ki67 labeling index and with anti-CD34 to observe microvessels. We correlated the tumor cell Ki67 labeling index and mitotic figure index with intratumoral microvessel density. Using a double labeling technique combining antibody MIB1 and anti-CD34, we measured intratumoral endothelial cell proliferation in 20 of these cases and correlated these findings with tumor cell Ki67 labeling index, mitotic figure index, and intratumoral microvessel density. The intratumoral Ki67-labeling index was 45-fold greater (P < 0.000001) than that of microvessels in adjacent benign breast. Yet, endothelial cell Ki67 labeling index did not correlate with intratumoral microvessel density, tumor cell Ki67 labeling index, or mitotic figure index nor did intratumoral microvessel density correlate with tumor cell Ki67 labeling index or mitotic figure index. These findings suggest that, although endothelial cells are actively proliferating within the tumor, intratumoral microvessel density and intratumoral endothelial cell proliferation are independent of each other and of tumor cell proliferation. Thus, intratumoral microvessel density, endothelial cell proliferation, and tumor cell proliferation may be regulated by separate mechanisms.

Tumor growth and metastasis require angiogenesis; and microvessel density, a measure of tumor angiogenesis, correlates with metastasis in breast and lung carcinoma. To determine how microvessel density correlated with metastasis in prostate carcinoma, we counted microvessels within the initial invasive carcinomas of 74 patients (29 with metastasis, 45 without). Microvessels were highlighted by immunostaining endothelial cells for factor VIII-related antigen. Without knowledge of the patient's cancer stage, microvessels were counted in a 200 field (0.739 mm2) in the most active areas of neovascularization. The mean microvessel count in tumors from patients with metastases was 76.8 microvessels per 200 field (median, 66; standard deviation, 44.6). The counts within carcinomas from patients without metastasis were significantly lower, 39.2 (median, 36; standard deviation, 18.6) (P < 0.0001). Microvessel counts increased with increasing Gleason's score (P < 0.0001), but this increase was present predominantly in the poorly differentiated tumors. Although Gleason's score also correlated with metastasis (P = 0.01), multivariate analysis showed that Gleason's score added no additional information to that provided by microvessel count alone. Assay of microvessel density within invasive tumors may prove valuable in selecting patients for aggressive adjuvant therapies in early prostate carcinoma.

The factor(s) that causes excessive mast cell (MC) proliferation in indolent forms of mastocytosis is not known, nor is it known whether that proliferation is a regulated clonal expansion or merely a non-neoplastic hyperplasia. Human MCs display phenotypes that depend on the microenvironment. Thus, if the phenotype of MCs in mastocytosis lesions is determined to be abnormal for that tissue site (and therefore the MCs are refractory to microenvironmental signals) then a clonal process would be suggested. The authors determined the phenotypes of MCs from the lesional skin of 17 patients with indolent mastocytosis and the bone marrows of 9 patients. They compared them with the phenotypes of MCs from the lesional skin of 8 patients with various dermatitides, the skin of 2 patients with idiopathic anaphylaxis, and the breast skin of 15 control patients. MCs from all the skin specimens showed the characteristic skin MC phenotype, with predominantly scroll-poor granules by ultrastructure and containing tryptase and chymase by immunofluorescence detection (the MCTC immunophenotype). The skin MCs of each patient bound avidin and contained carboxypeptidase by immunofluorescence detection. MCs from the bone marrow of patients with indolent mastocytosis, the source of progenitors, also showed the scroll-poor and MCTC phenotypes. These findings do not support an unregulated clonal expansion in indolent forms of mastocytosis. They are consistent with a non-neoplastic hyperplasia or possibly a clonal process in which MCs remain responsive to microenvironmental regulation.

Nuclear matrix proteins (NMP) are nonhistone proteins found in the nucleus of many eukaryotic cells. Furthermore certain NMPs are reported to be cell-type specific and expressed differentially by malignant cells. To study the specificity of NM-200.4 (an antibody reactive to NMPs extracted from cultured breast carcinoma cells of the T-47D line), cancers and benign tissues from multiple body sites were surveyed. All 17 breast carcinomas showed strong reactivity to tumor cell nuclei. Also nuclei from one of two lung carcinomas, a papillary thyroid carcinoma, an ovarian fibroma, and a lymphoma were strongly reactive. One leiomyosarcoma and a dermoid cyst were negative. Although 1 benign breast with duct hyperplasia showed moderate reactivity, only 1 of 10 benign breast biopsies without hyperplasia showed reactivity. Three of 4 skin biopsies, 2 liver biopsies, 6 of 9 kidney biopsies, and 5 of 10 gastrointestinal mucosal biopsies showed reactivity in benign nuclei. It is concluded that, although breast carcinoma nuclei showed the most consistent reactivity for NM-200.4, both benign and malignant nuclei from other body sites also show reactivity.

Cytogenetic analysis of two pulmonary chondroid hamartomas and nine breast adenofibromas revealed clonal chromosome aberrations in both hamartomas and in four breast tumors. To determine lineage of the cells with chromosome aberrations, a combined immunohistochemical/cytogenetic approach was developed that enabled simultaneous ascertainment of cytogenetic aberrations and immunohistochemical features in individual cells. Immunohistochemical/cytogenetic evaluation of one hamartoma and two adenofibromas demonstrated that neoplastic proliferation, in each case, was confined to the mesenchymal (stromal) component, whereas epithelial cells appeared to be reactive. Cytogenetically abnormal short-term cultures of the remaining hamartoma and another of the breast adenofibromas were composed entirely of mesenchymal elements, indicating mesenchymal clonality in those tumors as well. Our findings support redesignation of pulmonary chondroid hamartomas as 'pulmonary chondromas' and suggest that carcinomas developing within fibroadenomas arise from reactive epithelial proliferation. Combined immunohistochemical/cytogenetic analysis might be useful in the development of novel therapeutic approaches that selectively target neoplastic populations within solid tumors.

This article reviews the ultrastructural and immunohistochemical features of normal human mast cells (MC) at multiple tissue sites. Current literature indicates that granules containing discrete scrolls (scroll-rich morphology) are frequent in MC from bowel mucosa and lung, locations where the majority of MC show only tryptase immunoreactivity (MCT). In contrast, most MC from skin, breast parenchyma, axillary lymph nodes, and bowel submucosa are characterized by scroll-poor morphology (that is, granules are rimmed by incomplete scrolls forming parallel lamellae and containing central, amorphous granular material or grating/lattice-like structures) and show both tryptase and chymase immunoreactivity (MCTC). MC having granules with both scroll-rich and scroll-poor features can occur in all tissue sites, and an occasional MC, especially in lung and bowel, may show only chymase immunoreactivity (MCC). Chymase immunoreactivity in MC also is closely associated with avidin binding and carboxypeptidase reactivity. We conclude that there is ultrastructural and immunophenotypic diversity among normal human MC, although certain forms predominate in specific tissue environments. In skin, breast tissue, axillary lymph nodes, and bowel submucosa MC tend to have scroll-poor granules and stain for avidin, chymase, tryptase, and carboxypeptidase, whereas, in lung and bowel mucosa MC granules tend to be scroll-rich and stain only for tryptase with currently available reagents.

A bonded reversed phase, high pressure liquid chromatography (HPLC) method for serum quinidine and its major metabolite in serum, (3S)-3-hydroxyquinidine, is presented. The method employs toluene, rather than benzene for extraction of 100 microliter of serum, can utilize either absorbance or fluorescence detectors, and utilizes a column and equipment which is also suitable for theophylline analyses. Quinidine values in sera by the present method correlated well with fluorometric non-chromatographic methods using ethylene chloride (r = 0.932) or benzene-sulfuric acid (r = 0.950) for extraction of the quinidine. The comparison data suggest a therapeutic range for quinidine of 1.3--5.0 mg/liter when measured by HPLC. In over one year of routine use in a clinical chemistry laboratory, the method has proven to be rapid and precise with interassay coefficients of variation of 2.5--5.5%. No interferences with the HPLC method have yet been identified.

We investigated the kinetic characteristics of an enzyme immunoassay system (EMIT) for the determination of theophylline. Less than 10% of the glucose-6-phosphate and NAD+ are consumed and the glucose-6-P-dehydrogenase-theophylline complex is essentially saturated with these substrates during the course of the reaction. However, apparently as the result of antibody heterogeneity, the rate does change during the course of the reaction. As a result, the values of the kinetic parameters for the theophylline saturation curve vary with the timing interval chosen for measurement. We show that the values of these parameters govern the application of the available methods of calculating EMIT data, the graphical procedure suggested by the manufacturer, logit-log, log-log, and curve fitting. These studies (1) explain the basis of the graphical procedure and why it does not always provide proper calibration, (2) show that to appropriately understand the application of any of the calculation procedures one should determine the values of the kinetic constants of the theophylline saturation curve in the particular assay conditions, and (3) illustrate simple, practical procedures for determining the values of these constants for any instrument-EMIT assay system. Specific illustrations are shown for the EMIT theophylline system with two kinetic analyzers, the Abbott ABA-100 and Gilford 3500, with which markedly different reaction conditions are used.

The EMIT technique for theophylline measurement as adapted to the Abbott Bichromatic Analyzer (ABA-100), was compared to two other established procedures. EMIT results correlated well with those obtained with high pressure liquid chromatographic (HPLC) (r = 0.995, N = 54) and spectrophotometric (UV) (r = 0.95, N = 37) methods when the patient samples used were free of apparent interferences in the comparison methods. On samples exhibiting interferences with HPLC and/or UV methods, the EMIT assay gave the same results as a gas-liquid chromatographic procedure which showed no interferences. In addition, theophylline metabolites, xanthine analogs and many commonly administered drugs did not interfere with the EMIT theophylline assay. An interassay coefficient of variation of 3.5--6.5% was demonstrated. Our data indicate that the EMIT technique exhibits adequate precision and specificity for routine theophylline determinations. Unlike the HPLC or UV procedures, we have not encountered any interferences with the EMIT technique.