Laser micromachining of goldblack coatings.

Goldblack deposits have been used as high-absorption coatings for thermal infrared detectors for a number of years, principally on large single, or few pixel detectors. We present a new technique that allows the benefits of goldblack to be applied to the current generation of small pixel silicon micromachined thermal infrared detectors.

Porous polymer monoliths: simple and efficient mixers prepared by direct polymerization in the channels of microfluidic chips.

Porous monolithic polymers have been prepared by photoinitiated polymerization of mixtures consisting of 2-hydroxyethyl methacrylate, ethylene dimethacrylate, UV-sensitive free radical initiator and porogenic solvent within channels of specifically designed microfluidic chips and used as micromixers. Substituting azobisisobutyronitrile with 2,2-dimethoxy-2-phenylacetophenone considerably accelerated the kinetics of the polymerization. Mixtures of cyclohexanol and 1 -dodecanol and of hexane and methanol were used, respectively, to control the porous properties and therefore the mixing efficiency of the device. The performance of the monolithic mixers has been tested by pumping aqueous solutions of two fluorescent dyes at various flow rates and monitoring the point at which the boundary of both streams completely disappears. Best results were achieved with a monolithic mixer containing very large irregular pores.

Nonneoplastic diseases of aorta and pulmonary trunk--Part IV.

This five-part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part IV of the series discusses cystic medial degeneration, trauma, and congenital diseases of the aorta.

Nonneoplastic diseases of aorta and pulmonary trunk--Part III.

The five-part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more disease affect the aorta compared with the pulmonary trunk and right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part III of this five-part series discusses the etiology of aortic aneurysms and aortitis.

Nonneoplastic diseases of aorta and pulmonary trunk--Part I.

This five-part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part I of this five-part review discusses general concepts of aorta anatomy and aortic dissection.

Nonneoplastic diseases of aorta and pulmonary trunk--Part V.

This five-part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and the right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part V of this five-part series on diseases of the aorta and the pulmonary trunk focuses on nonneoplastic diseases of the pulmonary trunk and the right and left main pulmonary arteries.

Intracardiac thrombi: frequency, location, etiology, and complications: a morphologic review--Part V.

Intracardiac thrombus may develop as a consequence of multiple underlying cardiac disorders. Other systemic disorders may predispose formation of thrombus within the heart, or the heart may be the site of emboli in transit--thrombus originating elsewhere and traveling through the heart to the pulmonary or arterial circulation. Part V of this five-part series on intracardiac thrombus will focus on "migrating thrombi," miscellaneous systemic conditions associated with intracardiac thrombi, and echocardiographic detection of intracardiac thrombus.

Intracardiac thrombi: frequency, location, etiology, and complications: a morphologic review--Part IV.

Intracardiac thrombus may develop as a consequence of multiple underlying cardiac disorders. Valvular heart disease, in particular, rheumatic mitral stenosis is frequently associated with intracardiac thrombus. Part IV of this 5-part article on intracardiac thrombus focuses on the frequency and consequences of thrombus in valvular heart disease.

Intracardiac thrombi: frequency, location, etiology, and complications: a morphologic review--Part III.

Intracardiac thrombus may develop as a consequence of multiple underlying cardiac disorders. Left ventricular (LV) aneurysm following acute myocardial infarction has been associated with intra-aneurysmal thrombus and emboli. Part III of this 5-part article on intracardiac thrombus focuses on the frequency and consequence of thrombus associated with LV aneurysm.

Intracardiac thrombi: frequency, location, etiology, and complications: a morphologic review--Part II.

Intracardiac thrombus is a frequent finding at necropsy. Various cardiac disorders have been associated with its presence. Part II of this 5-part article focuses on atherosclerotic coronary heart disease (myocardial infarction) as an etiology for intracardiac thrombus.

Intracardiac thrombi: frequency, location, etiology, and complications: a morphologic review--Part I.

Intracardiac thrombus is a frequent finding at necropsy. Various cardiac disorders have been associated with its presence. Part I of this 5-part article focuses on classification by location and etiology and reviews primary cardiomyopathy as a specific condition associated with intracardiac thrombus.

Termination of health benefits for Pittston mine workers: impact on the health and security of miners and their families.

Mine workers represented by the United Mine Workers of America (UMWA) have had comprehensive medical care coverage since 1950. On February 1, 1988, UMWA employees of the Pittston Coal Group had their health care benefits abruptly terminated. Renewal of these benefits became a major reason for the subsequent UMWA strike against Pittston. In December, 1989, physician interviewers were organized to document the human experience of this termination of health care benefits. This report summarizes these interviews, and concludes that the UMWA experience in the Pittston coal fields is one example of the barriers to health care experienced by an increasing proportion of the United States population.

Immunoassay employing surface-enhanced Raman spectroscopy.

Surface-enhanced Raman scattering (SERS) was used to measure binding between biomolecules with mutual affinity, including antigen-antibody interactions. The conjugation of nitro groups onto bovine serum albumin enhanced their specific SERS activity 10(4)-fold. A dye, 2-[4'-hydroxyphenylazo]benzoic acid (HABA), with a major absorption at the Raman excitation frequency, demonstrated surface-enhanced resonance Raman scattering (SERRS) when captured from solution by avidin-coated silver films. Individual peak intensities showed a logarithmic relationship to the HABA concentration in solution over the range 10(-8) to 10(-5) M. Another resonance dye, p-dimethylaminoazobenzene (DAB) was covalently attached to an antibody directed against human thyroid stimulating hormone (TSH), without loss of antibody activity. The resultant conjugate was used in a sandwich immunoassay for TSH antigen: silver surfaces coated with anti-TSH antibody captured TSH antigen which in turn captured the DAB-anti-TSH antibody conjugate. A linear relationship was observed between the intensity of the resultant SERRS signals and the TSH antigen concentration over a range of from 4 to 60 microIU/ml. These results demonstrate the potential utility of the SERRS effect as a readout in a one-step, no wash immunoassay system.

Carbon nuclear magnetic resonance spectra of oligosaccharides isolated from human milk and ovarian cyst mucin.

Natural abundance Carbon-13 nuclear magnetic resonance spectra at 20 MHz were reported for the three common human milk oligosaccharides, lacto-N-tetraose and lacto-N-fucopentaoses I and II, as well as for two related tetra- and hexasaccharide alditols isolated from the alkaline borohydride degradation products of an ovarian cyst glycoprotein. Spectral assignments made with the help of deuterium-induced shift (DIS), attached proton test (APT), and T1 data indicated some very irregular glycosylation shifts which were attributed to effects of steric crowding and non-nearest-neighbor interactions. Samples as small as 10 mumol of oligosaccharide gave acceptable 20-MHz spectra with the use of a 5-mm probe coil.

Lewis phenotype of erythrocytes and Leb-active glycolipid in serum of pregnant women.

In an attempt to provide an explanation for the previously reported effect of pregnancy on the Lewis phenotype of erythrocytes, the level of Leb-active glycolipid in serum was compared with the reactions of erythrocytes, using samples obtained from 73 nonpregnant women, 74 women at the time of delivery, and 2 women at weekly intervals during their pregnancy. In this Swedish population, the frequency of the Le(a--b-) blood group increased from 11% in nonpregnant women to 36% in women at the time of delivery. Among Le(a--b+) women of all ABO groups, those who were A1 most often became (Leb-) during pregnancy. The change in phenotype occurred as early as the 24th week of gestation; the Leb antigen was again detectable within 6 weeks after delivery. The concentration of Leb glycolipid in serum, as measured by radioimmunoassay, decreased only slightly during pregnancy. The repartition of glycolipids, secondary to the increased ratio of lipoprotein to red cell mass that occurs during pregnancy, may account for the relative lack of Lewis glycolipid on erythrocytes.

Structure and biosynthesis of surface polymers containing polysialic acid in Escherichia coli.

Membranous sialyltransferase complexes from Escherichia coli K-235 catalyze the synthesis of surface polymers containing alpha-2,8-ketosidically linked polysialic acid. Undecaprenyl phosphate functions as an intermediate carrier of sialic acid (NeuNAc) residues between cytidine 5'-monophospho-N-acetylneuraminic acid (CMP-NeuNAc) and an endogenous acceptor (Troy, F.A., and McCloskey, M.A. (1979) J. Biol. Chem 254, 7377-7387). In vitro pulse-chase experiments now confirm that polymer elongation occurs by the addition of sialyl residues to the nonreducing termini of growing nascent chains. Sequential periodate oxidation and borohydride reduction of radiolabeled polysialic acid was used to quantitatively convert the terminal, nonreducing sialic acid to the 7-carbon analogue, 5-acetamido-3,5-dideoxy-L-arabino-2-heptulosonic acid (NeuNAc7). After complete hydrolysis of the polymers by neuraminidase, the ratio between NeuNAc and NeuNAc7 was used to determine the average degree of polymerization (D.P.). The membrane preparations used as a source of enzyme contained endogenous sialyl polymers that averaged 165 residues in length. During the first phase of in vitro synthesis, lasting about 90 min, 40 to 45 sialyl residues were transferred onto these endogenous acceptors. Subsequent in vitro incorporation increased at a slower, constant rate for at least 16 h. During this second phase of synthesis, the D.P. of newly synthesized chains remained relatively constant while the number of nonreducing terminal end groups, a measure of the number of new sialyl chains, increased. These results establish that individual polymer chains are rapidly elongated in vitro to a defined length of about 200 sialyl residues, then terminated and new chains started. The mechanism signaling chain termination, translocation of the sialyltransferase to a new acceptor, and chain reinitiation remains to be determined. Endogenous and enzymatically synthesized sialyl polymers were solubilized with Triton X-100 and purified to apparent homogeneity. Sialic acid accounted for approximately 93% of the mass of these polymers which had no free reducing terminal sialic acid. This position of the molecule is presumably occupied by an as yet unidentified component which links the sialyl polymer to the membrane.