Fragile sites and breakpoints in constitutional rearrangements and in human sperm chromosomes

Recently, it has been suggested that an association exists between breakpoints involved in constitutional rearrangements and fragile sites; however, statistical analyses of this relationship are controversial. We have analyzed 1200 breakpoint from different constitutional rearrangements, 1522 breakpoints with respect to their recurrence and 217 breakpoints from sperm chromosomes as reported by several authors. The coincidence between breakpoints and fragile sites was 35.3%, 43.6% and 41.9% respectively. The statistical significance of these coincidences depends on whether factors such as the relative length of the bands or the recurrence of the rearrangements are taken into account.

[Bacteremia caused by Salmonella non-typhi in patients infected with HIV]

All the cases of HIV infected patients diagnosed in our department during 1987 of Salmonella bacteremia are included in this report. Out of a total of 10 patients with both conditions, six were diagnosed of AIDS, three of AIDS related complex, and one presented an asymptomatic HIV infection. The mean age was 32.9 years (range 22 to 56). Eight of them were males, seven were intravenous drug addicts, and three were homosexual. Fever was observed in all cases and diarrhea in four of them. Salmonella enteritidis was isolated from the blood culture of nine patients and salmonella typhimurium from one. Salmonella enteritidis was isolated from the stool culture of 5 patients and Salmonella typhimurium and Campylobacter from the stool culture of one patient. Of the 10 patients 6 have died, 4 of them within the three weeks after the diagnosis of Salmonella non-typhi bacteremia, 2 have not relapsed and two patients were lost during follow up.

Crystal structures and spectroscopic studies of ternary compounds of Ni(II) with ethylenediamine and 5'GMP and 5'IMP

Two metal complexes [Ni(en)5'GMPH)2(H2O)2] (en).6.5H2O and [Ni(en)(5'IMPH)2(H2O)2].13H2O have been synthesized in the form of suitable crystals for x-ray crystallography (en = ethylenediamine, 5'GMP = guanosine 5'-monophosphate, 5'IMP = inosine 5'-monophosphate). The 5'GMP complex crystallizes in a monoclinic space group P21 (Z = 4) with a = 12.317(2), b = 28.417(4), c = 12.290(2)A, beta (deg) = 89.59(2). The 5'IMP complex is tetragonal, space group P4122 (Z = 4), with a = 12.119(3), b = 12.119(3), c = 28.560(4)A, beta (deg) = 90.0. The crystal structures of both complexes were refined from diffractometer data to conventional R values of 0.073 for the 5'GMP compound (5,284 observed reflections, 1,322 variables) and 0.030 for the 5'-IMP compound (1,529 observed reflections, 296 variables). In both structures, the Ni(II) is surrounded by two water molecules, one chelate ethylenediamine, and two nucleotide molecules. The synthesis was carried out from Ni(en)2Cl2.0.5H2O and the nucleotide in water medium. The dimer structure of the initial complex is broken, and one ethylenediamine is substituted by two molecules of the nucleotide with the N(7) of the purine ring in cis-position. Differences between both structures are largely due to retention in the structure or loss of the en molecule substituted and to the intermolecular hydrogen bonds of the en molecule coordinated. A third complex of composition [Ni(en)(5'IMPH)2(H2O)2] (en).6H2O similar to the 5'GMP complex has been obtained in the form of blue crystals, but unfortunately its crystal structure failed to be refined. This complex is isostructural with the monoclinic one.

Predicting pulmonary embolism in postoperative patients with deep venous thrombosis of lower limbs

Ventilation-perfusion lung scans were done in 70 patients admitted because of an iliofemoral deep vein thrombosis (DVT), and diagnosed by venography. Eighteen items of clinical and laboratory information were measured to predict the presence of lung scan abnormalities consistent with asymptomatic pulmonary embolism. Eighteen patients had perfusion defects in the lung scan that were classified as "high probability of pulmonary embolism", while the lung scan was normal in 32 patients. Patients with an idiopathic DVT were at high risk of pulmonary embolism, but those with a postoperative DVT had a low embolic risk. In patients with a postoperative DVT two factors predicted pulmonary embolism: those patients who developed symptomatic DVT after an operation but had a normal lung scan showed higher platelet counts than their preoperative levels. Conversely, it they developed a pulmonary embolism their platelet count dropped from their preoperative levels.

Derivatives of Co(II), Co(III), Ni(II), Cu(II), and Zn(II) with 5' AMP. Use as enzymatic labels with glycogen phosphorylase B

Some new derivatives of Co(II), Co(III), Ni(II), Cu(II), and Zn(II) with 5' AMP have been obtained, characterized by elemental analysis, infrared, electronic, and fluorescence spectroscopy. The activities of these complexes as substitutes of 5' AMP as allosteric activators of glycogen phosphorylase b have been tested. The derivatives that have no interaction with the phosphate group are good analogs of the natural allosteric activator; the complexes that have direct bonding between metallic ion and phosphate groups do not activate the enzyme.