Vascular endothelial growth factor (VEGF) induces plasminogen activators and plasminogen activator inhibitor-1 in microvascular endothelial cells.

Extracellular proteolysis is believed to be an essential component of the angiogenic process. The effects of VEGF, a recently described angiogenic factor, were assessed on PA activity and PA and PAI-1 mRNA levels in microvascular endothelial cells. u-PA and t-PA activity were increased by VEGF in a dose-dependent manner, with maximal induction at 30 ng/ml. u-PA and t-PA mRNAs were increased 7.5- and 8-fold respectively after 15 hours, and PAI-1 mRNA 4.5-fold after 4 hours exposure to VEGF. At equimolar concentrations (0.5 nM), VEGF was a more potent inducer of t-PA mRNA than bFGF, while bFGF was a more potent inducer of u-PA and PAI-1 mRNAs. In addition, VEGF induced u-PA and PAI-1 mRNAs with kinetics similar to those previously demonstrated for bFGF. These results demonstrate the regulation of PA and PAI-1 production by VEGF in microvascular endothelial cells and are in accord with the hypothesis that extracellular proteolysis, appropriately balanced by protease inhibitors, is required for normal capillary morphogenesis.     

Gene structure of mouse cathepsin B

The structure of a genomic DNA fragment encoding mouse cathepsin B was characterized. The genomic insert spans 15 kbp and contains 9 exons encoding the 339 amino acid residues of mouse preprocathepsin B. Intron break-points are not found at the junctions of the pre-peptide, pro-peptide and mature enzyme. Like other cysteine proteinase genes, the region around the cysteinyl active site is split by an intron, but in contrast with cathepsins L and H the intron break-point is located immediately after the active site.     

A microfluorometric method for alkaline phosphatase: Application to the various segments of the nephron

A microtechnique has been developed for the measurement of alkaline phosphatase in minute amounts of renal tissue. This microtechnique utilizes the known fluorescent property of 4-methylumbelliferyl phosphate following enzymatic hydrolysis. The reaction is sensitive and reproducible and is inhibited by l-bromotetramisole, a specific alkaline phosphatase inhibitor. The microdetermination of alkaline phosphatase activity in the various segments of the mouse nephron allowed the localization of the enzyme in the glomeruli, and in the proximal convoluted tubule where the activity progressively decreases from the capsule of Bowman to the more distal segments. The enzyme was absent from the pars recta or S3 and from the rest of the nephron. This technique is applicable to very small amounts (0.1 μg of protein) of any tissue containing alkaline phosphatase.     

DNA and protein content of mouse sperm: Implications regarding sperm chromatin structure

A variety of biochemical and histochemical techniques have been used to compare the composition of chromatin in sperm nuclei isolated from the epididymides of five mouse strains. The DNA content was determined by phosphorus analysis, deoxyribose analysis, absorption spectroscopy at 260 nm, and cytomorphometry following gallocyanine chrome alum staining. All four methods indicate that the mouse sperm nucleus contains approx. 3.3 pg DNA and that the DNA content does not vary significantly among the strains tested. Three different techniques, quantitative amino acid analysis, absorption spectroscopy at 230 nm, and sperm head density analysis in cesium chloride, were used to determine the protein content. Sperm nuclei from each strain of mouse were found to have a protein to DNA ratio of 0.9 and a chromatin protein content of 3 pg/nucleus. Comparisons of the basic proteins by disc gel electrophoresis demonstrate that the sperm nuclei contain only protamine and lack significant levels of somatic histones or transition proteins. The sperm from each strain contained both mouse protamine variants and the relative distribution of the two proteins did not appear to differ among strains. Using this information, we have been able to draw certain conclusions regarding DNA-protamine interactions and the mode of DNA packaging in the sperm nucleus. The most important of these is that the DNA in the mouse sperm nucleus cannot be packaged in nucleosomes. The protamines in sperm chromatin do not function as structural proteins, providing a subunit core around which the DNA is wrapped, but appear to completely neutralize the phosphodiester backbone of the DNA molecule, thereby minimizing the repulsion between neighboring segments of DNA and allowing it to be condensed into a biochemically inactive particle of genetic information.     

Delayed hypersensitivity and Ig level in 210 patients with chronic myeloid leukemia

Summary Serum immunoglobulin concentration and skin reactivity to at least three recall antigens were determined in 210 patients with chronic myeloid leukemia (CML). Immunoglobulin concentration was normal in the great majority of the patients. Skin tests were negative in 50 of 210 cases (24%). No relationship could be demonstrated between skin reactivity, age, time since diagnosis, WBC, lymphocyte count, and splenectomy. Prior antileukemic therapy was a major factor in determining the response to skin tests.S. Tura (Chairman) and M. Baccarani (Secretary), Cattedra di Ematologia dell'Università e Servizio di Ematologia dell'Ospedale S. Orsola, Bologna; G. de Sandre, G. Perona, G. Cetto, G. Pizzolo, Istituto di Patologia Medica e Cattedra di Ematologia dell'Università, Verona; P. Rambotti, B. Falini, Clinica Medica dell'Università, Perugia; T. Chisesi, G. Capnist, Divisione di Ematologia, Ospedale Civile, Vicenza; A. Cajozzo, P. Citarella, Cattedra di Ematologia dell'Università, Palermo; G. Broccia, Sezione di Ematologia, Ospedale Armando Businco, Cagliari; V. Liso, G. Troccoli, Clinica Medica II dell'Università, Bari; L. Bruzzese, G. Nappi, A. Abbadessa, Clinica Medica (I Facoltà) dell'Università, Napoli; A. Porcellini, C. Delfini, Divisione di Ematologia, Ospedali Riuniti, Pesaro; E. Cacciola, R. Giustolisi, R. Musso, V. Raimondi, Cattedra di Ematologia dell'Università, Catania; G. Torlontano, L. Geraci, Cattedra di Ematologia dell'Università, Chieti, e Divisione di Ematologia, Ospedale Civile, Pescara; F. Mandelli, G. Mariani, B. Monarca, N. Petti, Cattedra di Ematologia dell'Università, Roma; R. di Guglielmo, A. Miliani, Clinica Medica dell'Università, Firenze; C. Bernasconi, M. Lazzarino, G. Castelli, Divisione di Ematologia, Ospedale S. Matteo, Pavia; A. Alberti, S. Magro, Servizio di Ematologia, Ospedale Generale Regionale, Catanzaro; A. Neri, P. Iacopino, Divisione di Ematologia, Ospedali Riuniti, Reggio Calabria; R. Delsignore, M. C. Baroni, Istituto di Patologia Medica dell'Universita, Parma; E. Bajetta, S. Monfardini, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milano; S. Tognella, Istituto Scientifico di Medicina Interna, Cattedra di Clinica Medica 2R, Università, Genova.     

A new fluorometric method for determination of picomoles of inorganic phosphorus. Application to the renal tubular fluid

A new method for the determination of inorganic phosphorus (Pi) in 4 nl of renal tubular fluid is described. Phosphate is converted to hexadimolybdatophosphate, which is reacted with thiamine to produce a highly fluorescent thiochrome. The reaction is stable and reproducible. Problems of interference are minimal. Microdeterminations of Pi in the proximal tubules and glomerular filtrates of the rat yielded results similar to those published in the literature.     

Circular dichroism analysis of the ribosomal binding of initiation factor IF-3

The circular dichroism spectra of Escherichia coli 30 S ribosomal subunits have been determined between 200 and 320 nm in the presence and in the absence of initiation factor IF-3. The addition of IF-3 did not produce any major alteration of the circular dichroism spectrum of the 30 S subunits between 320 and 240 nm, but resulted in an increase of the negative ellipticity between 240 and 205 nm. The effect was maximal for an IF-3:30 S molar ratio of approximately one, and further addition of IF-3 did not lead to a further increase of ellipticity. A similar effect was not seen when the 30 S ribosomal subunits were previously heat-inactivated to destroy their IF-3 binding capacity. These data indicate that the ribosomal binding of IF-3 may be accompanied by an increase in the secondary structure of the ribosomal proteins, but does not involve any major net change in the secondary structure of the rRNA.     

Linkage between the B-cell specific receptor for monkey red blood cells and HL-A antigens in man-mouse hybrids

Immunogenetics - The established human lymphoid cell lines 6410 and WI-L2 exhibit the recently discovered receptor for monkey red blood cells (MRBC). This receptor is specific for B cells. These...     

Comparing sources of mobility for modelling the epidemic spread of Zika virus in Colombia

Timely, accurate, and comparative data on human mobility is of paramount importance for epidemic preparedness and response, but generally not available or easily accessible. Mobile phone metadata, typically in the form of Call Detail Records (CDRs), represents a powerful source of information on human movements at an unprecedented scale. In this work, we investigate the potential benefits of harnessing aggregated CDR-derived mobility to predict the 2015-2016 Zika virus (ZIKV) outbreak in Colombia, when compared to other traditional data sources. To simulate the spread of ZIKV at sub-national level in Colombia, we employ a stochastic metapopulation epidemic model for vector-borne diseases. Our model integrates detailed data on the key drivers of ZIKV spread, including the spatial heterogeneity of the mosquito abundance, and the exposure of the population to the virus due to environmental and socio-economic factors. Given the same modelling settings (i.e. initial conditions and epidemiological parameters), we perform in-silico simulations for each mobility network and assess their ability in reproducing the local outbreak as reported by the official surveillance data. We assess the performance of our epidemic modelling approach in capturing the ZIKV outbreak both nationally and sub-nationally. Our model estimates are strongly correlated with the surveillance data at the country level (Pearson’s r = 0.92 for the CDR-informed network). Moreover, we found strong performance of the model estimates generated by the CDR-informed mobility networks in reproducing the local outbreak observed at the sub-national level. Compared to the CDR-informed networks, the performance of the other mobility networks is either comparatively similar or substantially lower, with no added value in predicting the local epidemic. This suggests that mobile phone data captures a better picture of human mobility patterns. This work contributes to the ongoing discussion on the value of aggregated mobility estimates from CDRs data that, with appropriate data protection and privacy safeguards, can be used for social impact applications and humanitarian action.