Dual microcolumn immunoaffinity liquid chromatography: an analytical application to human plasma proteins

Dual-column microcolumn immunoaffinity chromatography was accomplished by coupling immunoaffinity (IAC) and reversed-phase high-performance liquid chromatography (RP-HPLC) analysis columns. The IAC support was prepared by hydrophobically adsorbing the appropriate antibody onto an octyl silica-based stationary phase contained in a 250-microns-l.d. fused-silica microcolumn. Once the antigen was captured, the antigen-subtracted human plasma could be sent to the RP-HPLC microcolumn for plasma profiling. The antigen was quantitated by desorbing it from the IAC column and transferring it to the RP-HPLC system. Human plasma profiles were generated after removal of albumin, and transferrin and alpha 1-antitrypsin were quantitated with nanogram sensitivity. All analyses were accomplished with less than 1 microL of human plasma.     

Surface plasmon based thermo-optic and temperature sensor for microfluidic thermometry

We report on a noninteracting technique for the thermal characterization of fluids based on surface plasmon resonance interrogation. Using liquid volumes less than 20 μl, we have determined the materials' thermo-optic coefficients with an accuracy of better than 1×10(-5) °C(-1) and demonstrated temperature sensing with an accuracy of 0.03 °C. The apparatus employs a low-power probe laser, requiring only a single wavelength, polarization, and interrogation angle for accurate characterization. The device is particularly suited for precise diagnostics of liquids and gases within microfluidic systems and may also be readily integrated into a variety of lab-on-chip platforms, providing rapid and accurate temperature diagnostics.     

The technology of halogen-free flame retardant phosphorus additives for polymeric systems

Halogen-free flame retardant additives based on phosphorus function by developing a protective char. A variety of additives are available, ranging from the element itself, in the form of amorphous red phosphorus, to specialty organophosphorus compounds, and examples of their use in a range of thermoplastics are given. Intumescent formulations based on phosphates are especially designed for polyolefins. The behavior of a typical intumescent system is described with respect to flame retardant performance, thermal stability, water sensitivity, and filler compatibility.     

Distributions of GABAA, GABAB, and benzodiazepine receptors in the forebrain and midbrain of pigeons

The single-stranded DNA parvoviruses occur in humans and many species of animals. In general, they are species-specific and capable of producing disease at any stage of life. Parvoviruses have a requirement to replicate in cells in a permissive S-phase of DNA mitosis. The infections may be cytolytic to select cell groups resulting in specific developmental defects or may produce more generalized effects such as anemia, pancytopenia, or hemorrhage. The fetus is at particular risk for damage because of the vast number of cells in active mitosis. The teratogenic effects may be severe, often resulting in fetal death. Infections in childhood and adulthood are more frequently mild to subclinical. Some of the teratogenic effects recognized in animal species have been identified in humans. With increased knowledge of parvovirus effects in animals, more pathogenic effects may be related to human parvoviral disease. The need for vaccination, currently used annually in many domestic animal species, continues to be evaluated for humans.     

Tyrosine kinase inhibition prevents deformation-stimulated vascular smooth muscle growth

The goal of this study was to determine the role of tyrosine phosphorylation in transducing deformation-stimulated vascular smooth muscle growth. Rat aorta-derived vascular smooth muscle cells were cultured on flexible silicone elastomer membranes and subjected to cyclic deformation (15 cycles per minute, deformed 2 seconds, relaxed 2 seconds). Deformation significantly increased proto-oncogene expression, [3H]thymidine incorporation, [3H]leucine incorporation, and cell number. Time course studies showed an 8-hour lag between initiation of cell deformation and onset of [3H]thymidine incorporation, with peak levels achieved after 18 to 24 hours. Western analysis of protein blots from deformed cells (10 minutes) demonstrated increased levels of phosphotyrosine-containing proteins having molecular weights of 110 to 130 and 70 to 80 kD. Deformation-stimulated tyrosine phosphorylation was prevented by the tyrosine kinase inhibitor Herbimycin A. Tyrosine kinase inhibition also prevented deformation-stimulated vascular smooth muscle cell growth as measured by [3H]thymidine incorporation. Cyclic deformation stimulates vascular smooth muscle proliferation through activation of tyrosine kinases. Inhibition of tyrosine phosphorylation is an effective means of preventing deformation-induced vascular smooth muscle growth in vitro.     

Recurrent sinopulmonary disease in a young adult

In 50 patients aged 60 +/- 4 operated for colorectal carcinoma simultaneous combined radionuclide phlebography (RNP) and pulmonary perfusion scintigraphy (PPS) using 99Tcm labeled macroaggregates of the human serum albumin (MAHSA) were performed within 20 postoperative days aiming to detect deep vein thrombosis (DVT) and pulmonary thromboembolism (PTE). The aim of the study was to determine the incidence and segmental DVT localization as well as incidence, localization and clinical characteristics of developed pulmonary perfusion disorders. Deep vein thrombosis was detected in 33 (66%) patients with rather uniform distribution in vein segments. According to their scintigraphic characteristics the findings suggested recent thrombosis in almost all cases (only two of them had signs of chronic thrombosis). Of patients with detected DVT 17 (52%) had pulmonary perfusion disorders of which 10 (59%) were unilateral (7 right and 3 left) and 7 (42%) bilateral. Characteristics and extent of perfusion defects suggested very probable PTE in 11 (65%) patients and less probable in 6 (35%). It has been concluded that patients operated for colorectal carcinoma were highly exposed to DVT and PTE development which necessitates all measures contributing to their prevention.     

Fluoroprostaglandins: synthesis and biological evaluation of the methyl esters of (+)-12-fluoro-, (-)-ent-12-fluoro-, (+)-15-epi-fluoro-, and (-)-ent-15 epi-12-fluoroprostaglandin F2 alpha

The synthesis and biological activity of the methyl esters of (+)-12-fluoroPGF2 alpha, (+)-15-epi-12-fluoroPGF2 alpha, (-)-ent-12-flurorPGF2 alpha, and (-)-ent-15-epi-12-fluoroPGF2 alpha are described. Each fluoroprostaglandin has been evaluated from pregnancy interruption in the hamster and smooth-muscle stimulating effects on gerbil colon and hamster uterine strips. All fluoroprostaglandins synthesized were shown to be neither substrates for the 15-hydroxyprostaglandin dehydrogenase nor inhibitors of the enzyme.