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In a recent issue of this Journal, Frank Steindl (1974), drawing on his previous article in the Journal of Political Economy (Steindl, 1971) which contained a reduced form of Carl Christ's "A Simple Macroeconomic Model with a Government Budget Restraint" (Christ, 1968), purported to show that the money multiplier is negative. The purpose of this paper is to show that Steindl's definition of equilibrium might be theoretically as well as empirically uninteresting, both because his model is largely vacuous and because it depends on a reaction between the economy and the government which may make his solution unachievable. [ABSTRACT FROM AUTHOR]

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference. [ABSTRACT FROM AUTHOR]

ABSTRACT Dyskeratosis congenita ( DC) is a telomere-mediated syndrome defined by mucocutaneous features. The X-linked mode of inheritance accounts for half the cases, and is thought to predominantly manifest in childhood as bone marrow failure. We identified two male probands who presented in the fifth decade with idiopathic pulmonary fibrosis and cancer. Their pedigrees displayed consecutively affected generations. Five of six females (83%) manifested mucocutaneous features of DC, and two had wound-healing complications. No mutations in autosomal dominant telomere genes were present, but exome sequencing revealed novel variants in the X-chromosome DKC1 gene that predicted missense mutations in conserved residues, p. Thr49 Ser and p.Pro409Arg. Variants segregated with the telomere phenotype, and affected females were heterozygotes, showing skewed X-inactivation. Telomerase RNA levels were compromised in cells from DKC1 mutation carriers, consistent with their pathogenic role. These findings indicate that females with heterozygous DKC1 mutations may be at increased risk for developing penetrant telomere phenotypes that, at times, may be associated with clinical morbidity. [ABSTRACT FROM AUTHOR]

The article discusses traits related to nonresectoscopic endometrial ablation, a popular treatment for patients suffering from heavy menstrual bleeding (HMB). A hypothermia phenomenon is also illustrated with different studies pertaining to the destruction of endometrium to the level of basal layer. Efficacy of endometrial ablation is also explained and it clarifies that endometrial ablation is a valuable device to treat some women with the symptom of HMB.

Debates on whether residents should be trained to do abortions in the U.S. Advantage of learning elective abortion to obstetrics and gynecology residents; Legal ramification of forcing residents into abortion training.

The article highlights the issues explored at a roundtable discussion attended by U.S. obstetricians/gynecologists, focusing on how the professional liability insurance crisis came about to speculating about the prospects for reforming or even completely replacing the existing tort system. It offers information on several proposals that have been made for tort reform. The article also assesses whether caps work, as explored by the panelists. INSET: Definitions of some common tort terms.

Endothelial cell lines have been established from cells that were isolated from porcine yolk sacs from day 18 and day 22 embryos and propagated in vitro under various growth conditions. After expansion in vitro, the general properties of the cells proved similar for the different media used. The endothelial cells expressed cell surface receptors for acetylated low-density lipoprotein and also expressed cell surface-associated angiotensin-converting enzyme. The cells showed a characteristically high level of binding for Bandeiraea simplicifolia lectin I and Dolichos biflorus agglutinin but did not bind significant amounts of Ulex europaeus lectin I. The cells expressed low but serologically detectable levels of Class I major histocompatibility complex (MHC) antigens but failed to bind antibodies directed against Class II MHC antigens. α5β1 integrins were weakly expressed, whereas vascular cell adhesion molecule-1 (CD106) and αvβ3 integrins were not detected. Three-dimensional tube formation was readily observed in cultures grown on Matrigel and occurrel even in uncoated plastic dishes in the absence of Matrigel. In contrast to most of the adult porcine endothelial cells, yolk sacderived endothelial cells did not posses serologically detectable receptors for porcine growth hormone (GH), an observation consistent with the finding that GH did not increase the proliferative rate of these cells. Electron microscopic examination demonstrated the presence of Weibel-Palade bodies, tight endothelial cell junctions, and typical rough endoplasmic reticulum. Exposure of the cells to either concanavalin-A-stimulated porcine splenocyte culture supernatants or to human tumor necrosis factor α did not cause upregulation of VCAM-1 or Class II MHC antigens. Addition of prrcine interferon-γ led to an increase in the level of expression of Class I MHC. Yolk sac endothelial cells from day 22 embryos showed a low but detectable level of expression of Class II MHC antigens, whereas the endothelial cells from day 18 embryos showed no expression of Class II antigens after interferon-γ stimulation. The cells maintained competence to develop vascular structures in vitro and could do so after coinjection with murine tumor cells into adult, immunocompromised mice. [ABSTRACT FROM AUTHOR]

Examines hematopoietic colony-forming cells derived from human embryonic stem cells. Differentiation of human embryonic stem (ES) cells; Requirement of fetal bovine serum for the differentiation; Selection of CD34 cells from human ES cells.

Many studies of angiogenesis inducers and inhibitors rely on in vitro or in vivo models as indicators of efficacy. However, as valuable as these models are, there are limitations to each one of these. This overview describes some of the principal methods now in use and discusses the advantages and some of the limitations of these methods. It is suggested that multiple assays, involving both in vitro and in vivo assays, are at present the best way to minimize the problems inherent in any specific assay. [ABSTRACT FROM AUTHOR]

Background: Psoriasis is a common and persistent disease characterized chiefly by marked epidermal and endothelial cell proliferation and inflammation. These changes are likely a result of activated T lymphocytes infiltrating skin tissue or, in the case of psoriatic arthritis, the joints. Objective: To test the hypothesis that the antimetabolite 6-thioguanine (Sigma-Aldrich, St Louis, Mo) might be an effective treatment for psoriasis vulgaris because of its antilymphocytic effects. Methods: Twenty patients with moderate to severe plaque-type psoriasis were treated with 6-thioguanine for 6 months. The clinical disease was assessed by the psoriasis severity index. Biopsy specimens obtained from lesional skin before treatment and after 1 and 2 months of treatment were examined for disease-related abnormalities using histochemical and computer-assisted image analysis. Antiproliferative effects of 6-thioguanine were compared in human keratinocytes and mitogen-activated lymphocytes over a range of drug concentrations, while viability, cell-cycle, and DNA fragmentation analysis were done using flow cytometry-based assays. Results: After 6 months of treatment, disease severity in 18 of 20 patients showed a significant response to 6-thioguanine: 12 patients were completely cleared of trace disease; 6 showed marked clinical improvement; and 2 did not respond. Patients showed reductions in peripheral blood lymphocytes and total leukocytes, but therapeutic response correlated best with cutaneous T-cell depletion. In vitro assays established that 6-thioguanine has major cytotoxic effects (apparently S-phase specific) on activated T lymphocytes via the induction of apoptosis. Keratinocytes and unactivated T cells, on the other hand, were largely unaffected by incubation with 6-thioguanine. Conclusions: 6-Thioguanine is effective for the treatment of moderate to severe plaque-type psoriasis, and may be safe when given for defined periods and with careful hematologic... [ABSTRACT FROM AUTHOR]

Evidence is presented which indicates that differentiation of immunocompetence is achieved early in development, with some aspects of the immune system maturing concomitant with the appearance of blood-borne cells and thymic lymphocytes. Experiments are described which show that long-lasting, serum-mediated unresponsiveness to heterologous erythrocytes can be induced by injection of soluble factors released from such erythrocytes. These two lines of investigation lead to the hypothesis that tolerance may be achieved during development by the release, from various stem cells, of soluble factors which induce in the developing embryo a series of blocking factors. These factors subsequently are effective in preventing immune recognition net only of the stem cells themselves but also of their differentiated progeny. [ABSTRACT FROM PUBLISHER]

Discusses the bias in the results of the causality tests between Canadian money and income conducted by James Barth and James Bennett, because of two errors. Error in the filter used for the data; Failure to eliminate autocorrelation in the residuals; Problems that may arise when testing for causality with regression analysis.

The purpose of this study was to isolate endothelial cells from different organs of porcine fetuses and to examine the binding of endothelial markers including lectins. Endothelial cells were isolated from the aorta, cerebral cortex, myocardium, ovary and testis. Binding of the antibodies to von Willebrand factor (vWF) and angiotensin converting enzyme (ACE), the presence of Weibel Palade bodies (WPB), uptake of acetylated low density lipoprotein (acLDL), and labelling with the lectins Bandeiraea simplicifolia agglutinin I (BS I), Peanut agglutinin (PNA), Dolichos biflorus agglutinin (DBA) and Ulex europaeus agglutinin I (UEA I) were examined. Cell preparations displayed cobblestone-like morphology with the exception of testicular endothelium, which formed arcuate structures. Endothelium isolated from the brain labelled more strongly than any other cell line with the lectin PNA, but it did not express ACE. In contrast to other cell preparations, myocardial endothelium showed very low binding of anti-vWF. Ovarian endothelium was able to perform in vitro angiogenesis. Moreover, these endothelial cells possessed the largest number of WPB. Testicular endothelium displayed highest binding of vWF. Endothelium isolated from the aorta, in contrast to all other endothelial cells, did not take up acLDL. These results demonstrate that organ- and tissue-specific heterogeneity is already expressed in fetal endothelium. [ABSTRACT FROM AUTHOR]

Our purpose here is to examine whether this association and causal relationship can be detected using reduced form relationships in the time and frequency domains. We hasten to add that not finding a relationship should not lead one to infer that none exists. The reduced form single equation model will be incapable of detecting a relationship when important other variables are omitted or if one of the variables is a control variable being effectively used to offset the exogenous disturbances on a target variable in one country in such a way as to destroy the correlation between the control variable and the target variable (Kochin, 1972). [ABSTRACT FROM AUTHOR]

We report on the isolation and propagation of endothelial cells from the mouse embryonic yolk sac, the earliest site of blood vessel development, and on the advantages of a hypervascular transgenic mouse source of these cells. These transgenic mice express multiple copies of an activated allele of the human fps/fes proto-oncogene and display hypervascularity progressing to multifocal hemangiomas. This phenotype suggested a role of the fps/fes proto-oncogene in vasculogenesis and angiogenesis and led us to investigate the growth characteristics of yolk-sac-derived endothelial cells from transgenic fps/fes embryos. We have established eight independent cell clones from a mixture of transgenic and control yolk sacs from Day 12 embryos. Southern blot hybridization analysis showed all eight clones to be derived from transgenic cells suggesting a growth advantage of cells carrying the activated fps/fes gene. A cell line, Clone 166 (C166), established from one of these clones, was more fully characterized. C166 exhibits normal endothelial characteristics, such as rearrangement into tubelike structures when placed on Matrigel, expression of angiotensin converting enzyme, retention of cobblestone morphology at confluence, and the presence of cell surface receptors for acetylated low density lipoprotein. The cells constitutively express murine endothelial cell adhesion molecule VCAM-1 and the vascular addressin identified by antibody MECA-99. As expected, the cell line expresses high levels of the cytoplasmic protein-tyrosine kinase encoded by the fps/fes proto-oncogene. The clone we have described as well as other endothelial cell lines that we have established from the mouse embryonic yolk sac should prove useful for the study of endothelial cell differentiation and for the determination of the mechanisms underlying the establishment of organ-specific endothelial cell heterogeneity. [ABSTRACT FROM AUTHOR]

Endothelial cells of the NMRI mouse strain express a cell surface glycoprotein recognized by the lectin Dolichos biflorus agglutinin (DBA). This study documents a marked organ-specific increase in DBA-specific lectin binding of myocardium-derived endothelial cells (MEC) of the NMRI/GSF mouse during in vitro cultivation. An up to 20-fold increase in DBA binding sites is observed in long-term culture, an increase not found in other NMRI-derived endothelial cell lines (e.g., brain, aorta). The increase appears restricted to DBA in that binding with other lectins (PNA, WGA) was unaltered. NMRI MEC cultures maintain typical endothelial cell attributes such as cobblestone morphology on confluence, expression of endothelial cell-specific surface markers, and production of angiotensin-converting enzyme. Cultures routinely become aneuploid within 4 passages, several passages before upregulation of the DBA binding site(s). Myocardial endothelial cells sorted to obtain DBA and DBA cell populations generally maintained their sorted phenotype for 3 to 4 passages. Limiting dilution cloning resulted in clones varying in DBA expression. Clones for DBA expression maintained their DBA affinity for at least 10 passages (>30 doublings), whereas DBA clones gave rise to varying numbers of DBA cells within 2 to 4 passages. We hypothesize that the change in DBA affinity accompanies in vitro aging, that the change is independent of alterations in karyotype, and that the increase in DBA affinity may reflect a change in one or more other endothelial cell properties. Additional studies will be necessary to determine whether the in vitro changes are correlated with specific functional alterations and whether they accurately reflect progressive changes of MEC in vivo. [ABSTRACT FROM AUTHOR]

The mass spectra of several 4,5-disubstituted-2-oxazolidones and several related N-methyl derivatives have been determined. Fragmentation has been found to be a function of three factors: (1) the size of the alkyl function at C-5, (2) the location of the aryl substituent, and (3) replacement of NH by NCH3. In particular, aryl or bulky alkyl groups substituted at C-5 result in protonated aldehyde derived from hydrogen rearrangement from nitrogen. With other substituents, the most intense ions are nitrogen containing fragments. In the latter case the fragmentation pathway has been elucidated with the aid of metastable peaks observed using defocusing techniques. [ABSTRACT FROM AUTHOR]

The model developed by Floyd (1965) to show the effects of farm price supports on the returns to the factors in farming is based on widely accepted assumptions and could be applied to a wide range of economic problems. However, the model is overdetermined, and Floyd's solutions are incorrect. Floyd attempted to solve his model with nominal prices, thereby introducing "money illusion" in a set of relationships which may be depicted by a two-space isoquant map where the slope of a linear budget constraint is a relative (real) price. I will demonstrate that the model is overdetermined by solving the five-equation system with four of the equations. I then briefly discuss the inconsistencies in Floyd's solutions. My alternative model reduces the elasticities Floyd sought to the reciprocal of the relative factor shares and allows estimates of the long-run supply of farm output using the parameters from Floyd's article. The elasticities of supply for factors A and B are epsilon[sub a] and epsilon[sub b], respectively, and are assumed to be constant parameters, while P[sub x], the price of units of X, is considered a nonconstant parameter.[1] The system is held to contain five unknownns (a, b, P[sub a], P[sub b], X) leading to a determinate solution to the first five equations. [ABSTRACT FROM AUTHOR]

Discusses 'purple toes' as a sequela of oral coumarin drug therapy.

The article present an assistance in the case of the U.S. Consumer Price Index (CPI). It was an instance in which it was found that the widely used ratio to moving average filter, the X-II Variant of the Census Method II of Seasonal Adjustment. A check for the presence of seasonality is made in the X-II program by conducting an analysis of variance based on seasonal-irregular ratios grouped by months, where these ratios, subject to some minor modifications, are the quotient of the original series, and a centered 12-month moving average. The F-statistic computed by X-11 from monthly data of the U.S. CPI from 1953 to 1975 is highly significant, thereby indicating the presence of stable seasonality in this series at the 99% level of confidence. It is concluded that users of the X-11 should carefully check their results-preferably by generating an autospectrum of the data before and alter seasonal adjustment, as well as the cross-spectrum between the adjusted and unadjusted series.

The article presents a speech by University of Wisconsin zoologist Robert Auerbach, delivered at the the National Conference on Growth and Development in 1971 in which he discusses tissue interactions in embryonic development.

Hypopigmentation at a site of application of a tourniquet has to our knowledge been reported in the literature. We are reporting such a case. We have conjectured that this hypopigmentation may be due to temporary anoxia suffered by melanocytes. [ABSTRACT FROM AUTHOR]