Search PubMed⌕ Search

Biomedical subjects

J Larsen

Publications and source records attributed to J Larsen.

207 records · Page 12Linked to original sources

Biocompatibility of white cell filters as evaluated by complement activation.

The biocompatibility of nine different white cell filters was examined by analysis of complement activation in plasma specimens obtained from blood components before and after filtration. Filters for both red cell (RBC) concentrates and platelet concentrates (PCs) were tested. It was found in all of the filters tested that the postfiltration levels of complement activation products were not higher than the prefiltration levels in RBC concentrates and PCs. One exception was the filtration of multiple PCs with Imugard IG-500, in which case a rise in C3 activation products was seen. Moreover, there was a significant rise in C3 activation products, but not the terminal complement complex, when plasma was filtered through Imugard E, which contrasted with results with the other filters. High initial and storage time-dependent levels, especially of C3 activation products, were observed in the PCs, probably due to their processing at room temperature. It can be concluded that the majority of the filters tested do not activate complement.

Blood Platelets↗

Intestinal transplantation in pediatric patients: a nursing challenge: Part One: Evaluation for intestinal transplantation.

Intestinal transplantation offers hope to children with intestinal failure and life-threatening complications of parenteral nutrition (PN). As more transplant centers are adding intestinal transplantation to their existing programs, new challenges are presented to nursing professionals. This three-part series will provide information for nursing professionals regarding evaluation for intestinal transplantation, donor preparation, the surgical procedure, immediate postoperative care of the transplant recipient, complications of intestinal transplantation, and long-term care of the intestinal transplant patient. Part 1 will discuss the indications for intestinal transplantation, the evaluation of patients for intestinal transplantation, the process of listing patients for intestinal transplantation, and the waiting time for donor organs for intestinal transplantation. The information presented represents the approach taken at University of Nebraska Medical Center.

Child↗

Intestinal transplantation in pediatric patients: a nursing challenge. Part 2: Intestinal transplantation and the immediate postoperative period.

Intestinal transplantation offers new hope to children with intestinal failure and life-threatening complications of parenteral nutrition. As more transplant centers are adding intestinal transplantation to their existing programs, new challenges are presented to nursing professionals. This three-part series will provide information for nursing professionals regarding evaluation for intestinal transplantation, donor preparation, the surgical procedure, immediate postoperative care of the transplant recipient, and long-term care of the intestinal transplant recipient. This article focuses on donor selection and preparation, the surgical procedure for intestinal transplantation, the immediate postoperative course, immunosuppression, rejection, infections, fluid and electrolyte support, and nutrition. The information presented represents the approach taken at University of Nebraska Medical Center/Nebraska Health Systems.

Aftercare↗

Patterns and trends of sexual behavior, HIV testing, and HIV prevalence among all sexually transmitted disease clinic attenders in Denmark.

BACKGROUND AND OBJECTIVES: Persons attending a sexually transmitted disease (STD) clinic have shown to be at a higher risk for HIV infection than the population in general. We evaluate the patterns of HIV prevalence and testing in relation to reported risk behavior. STUDY DESIGN: Data have been collected on all new attenders at the Danish STD clinics. The study period was January 1, 1990 through March 1992. RESULTS: Testing for HIV was accepted by 74% and more often by women than men and more outside Copenhagen than in the city itself. Acceptance was lowest among homo/bisexual men seen in Copenhagen. The HIV prevalence was highest among homo/bisexual men with drug use (10.0%) and lowest among heterosexual men (0.3%) and women (0.2%). Among heterosexuals the test activity increased over time, and the test activity increased and the prevalence of HIV antibodies decreased with the number of reported sex partners. Among heterosexuals HIV infection was associated with not being born in Denmark and age (> or = 30 years old in women and > or = 35 years old in men). CONCLUSION: These results are relevant for the national HIV surveillance programs and campaigns, and stress the importance of offering HIV testing to all persons attending for an STD examination.

AIDS Serodiagnosis↗

Structural and functional characterization of paramecium dynein: initial studies.

Dynein arms and isolated dynein from Paramecium tetraurelia ciliary axonemes are comparable in structure, direction of force generation, and microtubule translocation ability to other dyneins. In situ arms have dimensions and substructure similar to those of Tetrahymena. Based on spoke arrangement in intact axonemes, arms translocate axonemal microtubules in sliding such that active dynein arms are (-) end directed motors and the doublet to which the body and cape of the arms binds (N) translocates the adjacent doublet (N + 1) tipward. After salt extraction, based on ATPase activity, paramecium dynein is found as a 22S and a 14S species. The 22S dynein is a three-headed molecule that has unfolded from the in situ dimensions; the 14S dynein is single headed. Both dyneins can be photocleaved by UV light (350 nm) in the presence of Mg2+, ATP and vanadate; the photocleavage pattern of 22S dynein differs from that seen with Tetrahymena. Both isolated dyneins translocate taxol-stabilized, bovine brain microtubules in vitro. Under standard conditions, 22S dynein, like comparable dyneins from other organisms, translocates at velocities that are about three times faster than 14S dynein.

Animals↗

Numerical simulation and experimental validation of blood flow in arteries with structured-tree outflow conditions.

Blood flow in the large systemic arteries is modeled using one-dimensional equations derived from the axisymmetric Navier-Stokes equations for flow in compliant and tapering vessels. The arterial tree is truncated after the first few generations of large arteries with the remaining small arteries and arterioles providing outflow boundary conditions for the large arteries. By modeling the small arteries and arterioles as a structured tree, a semi-analytical approach based on a linearized version of the governing equations can be used to derive an expression for the root impedance of the structured tree in the frequency domain. In the time domain, this provides the proper outflow boundary condition. The structured tree is a binary asymmetric tree in which the radii of the daughter vessels are scaled linearly with the radius of the parent vessel. Blood flow and pressure in the large vessels are computed as functions of time and axial distance within each of the arteries. Comparison between the simulations and magnetic resonance measurements in the ascending aorta and nine peripheral locations in one individual shows excellent agreement between the two.

Adult↗

Necrotizing fasciitis in congenital lymphedema. Case report.

Severe necrotizing fasciitis of the left leg and the trunk is described in a patient with congenital lymphedema. About 20% of the subcutaneous tissue and fascia was involved, with rapidly spreading necrosis and secondary toxemia. Lymphedema has not previously been reported as a factor predisposing to necrotizing fasciitis. Treatment is discussed.

Debridement↗