The effect of low-dose heparin on hypercoagulability following abdominal aortic surgery.

The effect of low-dose heparin on postoperative hypercoagulability was assessed using thrombelastography (TEG) in eighteen patients undergoing elective abdominal aortic surgery. Patients received unfractionated heparin 5000IU bd SC commencing on the first postoperative day. Native whole blood TEG was performed preoperatively and on day two postoperatively.

Evaluation of the TAS coagulation analyzer for monitoring heparin effect in cardiac surgical patients.

Objective: To assess the relationship between the Thrombolytic Assessment System (TAS); (Cardiovascular Diagnostics, Inc, Raleigh, NC) measurements and heparin levels in cardiac surgical patients.

Design: Equipment evaluation in vitro and in vivo.

Setting: A university teaching hospital.

Anogenital papillomavirus infections in children.

Over the years, our impression of human papillomavirus has changed. Once thought of as the cause of relatively insignificant skin lesions, its significant role in malignancy of epithelia and mucosa throughout the body is beginning to be understood. Also changing, although not as rapidly as we would like is our understanding of how human papillomavirus infects the body, the concept of latency, our responses to infection, and how to modify or boost those responses so as to overcome infection.

A week in the life of a hospital.

The same urgency and intellect that America's teaching hospitals apply to saving lives is now also going into saving the institutions themselves. All across the country, academic medical centers are trying to figure out how to marry progress with profits. At the Duke University Medical Center, TIME visits the front line in the war between money and medicine.

Estimation of the effect of increasing UVB exposure on the human immune system and related resistance to infectious diseases and tumours.

Exposure to UV light has, besides some beneficial effects (vitamin D production), many harmful effects on human health. UVB irradiation has been shown to suppress both systemic and local immune responses to a variety of antigens, including some microorganisms. However, it is still not known whether such immunomodulating effects may lead to an increase in the number and severity of certain tumours and/or infections in humans.

Safe Child Penarth: experience with a Safe Community strategy for preventing injuries to children.

Objectives: To evaluate the process of establishing a Safe Community project for children.

Design: A descriptive study.

Setting: Penarth, a town (population 20,430) Vale of Glamorgan, South Wales.

Hydrogen bonding in helical polypeptides from molecular dynamics simulations and amide hydrogen exchange analysis: alamethicin and melittin in methanol.

Molecular dynamics simulations of ion channel peptides alamethicin and melittin, solvated in methanol at 27 degrees C, were run with either regular alpha-helical starting structures (alamethicin, 1 ns; melittin 500 ps either with or without chloride counterions), or with the x-ray crystal coordinates of alamethicin as a starting structure (1 ns). The hydrogen bond patterns and stabilities were characterized by analysis of the dynamics trajectories with specified hydrogen bond angle and distance criteria, and were compared with hydrogen bond patterns and stabilities previously determined from high-resolution NMR structural analysis and amide hydrogen exchange measurements in methanol. The two alamethicin simulations rapidly converged to a persistent hydrogen bond pattern with a high level of 3(10) hydrogen bonding involving the amide NH's of residues 3, 4, 9, 15, and 18.

Liver transplantation in Western Australia: improved services to an isolated population.

Objective: To assess performance of the Western Australian Liver Transplantation Service in the light of debate about whether small transplant centres can produce optimal outcomes.

Design: Review of patient data collected prospectively and confirmed by retrospective casenote review.

Subjects: All patients referred to the Western Australian Liver Transplantation Assessment Panel.

Photogenotoxicity of skin phototumorigenic fluoroquinolone antibiotics detected using the comet assay.

The fluoroquinolone (FQ) antibiotics photosensitize human skin to solar UV radiation and are reported to photosensitize tumor formation in mouse skin. As tumor initiation will not occur without genotoxic insult, we examined the potential of ciprofloxacin, lomefloxacin, fleroxacin, BAYy3118 (a recently developed monofluorinated quinolone) and a nalidixic acid to photosensitize DNA damage in V79 hamster fibroblasts in vitro. Cells were exposed to 37.

Effect of low concentrations of prostacyclin on platelet function in vitro.

The study was performed to determine the possible direct effects of low concentrations of prostacyclin that might spill over into the systemic circulation during the administration of inhaled aerosolized prostacyclin. Platelet aggregation in response to adenosine diphosphate and collagen, as well as measurement of the maximum amplitude of the thrombelastograph (TEG), was undertaken in vitro using venous blood exposed to low concentrations of prostacyclin (0, 10, 100 and 500 pg/ml) from eight healthy volunteers. There were statistically significant reductions in parameters of platelet aggregation in response to the agonists adenosine diphosphate (1 mumol/l and 8 mumol/l) and collagen (10 mumol/l) following exposure to as little as 10 pg/ml of prostacyclin.

Helix bending in alamethicin: molecular dynamics simulations and amide hydrogen exchange in methanol.

Molecular dynamics simulations of alamethicin in methanol were carried out with either a regular alpha-helical conformation or the x-ray crystal structure as starting structures. The structures rapidly converged to a well-defined hydrogen-bonding pattern with mixed alpha-helical and 3(10)-helical hydrogen bonds, consistent with NMR structural characterization, and did not unfold throughout the 1-ns simulation, despite some sizable backbone fluctuations involving reversible breaking of helical hydrogen bonds. Bending of the helical structure around residues Aib10-Aib13 was associated with reversible flips of the peptide bonds involving G11 (Aib10-G11 or G11-L12 peptide bonds), yielding discrete structural states in which the Aib10 carbonyl or (rarely) the G11 carbonyl was oriented away from the peptide helix.

Risk prediction in coronary artery surgery: a comparison of four risk scores.

Objective: To determine which of four proposed risk scores best predicts immediate outcome of cardiac surgery.

Design: Observational cohort study.

Setting: Sir Charles Gairdner Hospital (a university teaching hospital), Perth, Western Australia, 18 March 1993 to 5 March 1996.

Quercetin prevents UV-induced local immunosuppression, but does not affect UV-induced tumor growth in SKH-1 hairless mice.

Ultraviolet is thought to induce skin tumors by its dual activity as a mutagenic agent and a suppressor of cell-mediated immunity. In the present study the effects of quercetin, a flavonoid-containing compound, on carcinogenesis and immunosuppression were studied in SKH hairless mice exposed to suberythemal doses of UV for up to 17 weeks. It was found that quercetin did not affect the onset or growth of non-melanoma skin tumors resulting from UV exposure.

Thoracic spinal fracture in a rugby league footballer.

Purpose: The report describes the mechanisms and sequelae of the first case of thoracic vertebral fracture to be reported in a rugby league footballer.

Case Summary: The injury was sustained as the result of a legal shoulder tackle. The player exhibited no sign other than dorsal midthoracic tenderness and paraspinal muscle spasm.

Photohaemolysis assay for drug phototoxicity complicated by 'bleaching' of released haemoglobin.

The phototoxic potential of several non-steroidal anti-inflammatory drugs and quinolone antibiotics was assessed using the photohaemolysis assay. In this system, human erythrocytes are irradiated (UVA radiation 320-400 nm) from below in the presence of suspected photosensitizers. Photohaemolysis with ketoprofen, tiaprofenic acid or nalidixic acid was initially concentration dependent, but photohaemolysis apparently decreased at higher drug concentrations.

Effects of phototherapy on the production of cytokines by peripheral blood mononuclear cells and on systemic antibody responses in patients with psoriasis.

Exposure to ultraviolet B (UVB) radiation results in the suppression of many cell-mediated immune responses, and recent studies mice and murine cells in vitro suggest a shift from a T-helper 1 (Th1) to a Th2 type of response on irradiation. Active psoriasis is considered to be a Th1-type disorder, chiefly on the basis of the cytokines produced by inflammatory cells in psoriatic lesions. We investigated the effect of phototherapy in patients with psoriasis on the cytokine profile of mitogen-stimulated mononuclear cells from peripheral blood and the concentration of IgG subclasses and IgE in the plasma.

The effect of aprotinin on thrombelastography in vitro.

The effect of low dose (50 KIU/ml) and high dose (200 KIU/ml) aprotinin on standard thrombelastographic variables (r, K, alpha, MA) was examined in vitro using blood from forty ASA Class 1 patients. Both concentrations of aprotinin resulted in minor increases in r time above the normal range (P < 0.05).

Sensitivity and specificity of the Hemochron, Hemotec and APTT for the detection of low concentrations of heparin.

This study compared two bedside methods recommended for the detection of low concentrations of heparin and the activated partial thromboplastin time (APTT), with reference to a laboratory measure of heparin concentration. Patients undergoing cardiopulmonary bypass had blood drawn at four stages when low levels of heparin could be expected. At each stage four tests were performed: whole blood clotting time using a Hemochron analyser with a Saline-Rinsed test cartridge, whole blood clotting time using a Hemotec analyser with a High Range Heparinase test cartridge, APTT, and heparin concentration by polybrene neutralization.

Progressive eruptive histiocytomas.

We describe progressive eruptive lesions that have been appearing on a 50-year-old Filipino man for the past 9 years. They are characterized by smooth, brown, firm nodules mainly on the head and torso. Histologic examination shows dermal collections of lipid-filled histiocytes and Touton-type giant cells.

Investigating the red shift between in vitro and in vivo urocanic acid photoisomerization action spectra.

Trans-urocanic acid (UCA) is found in the upper layer of the skin and UV irradiation induces its photoisomerization to cis-UCA. Cis-UCA mimics some of the immunosuppressive properties of UV exposure. The wavelength dependence for in vitro photoisomerization of trans-UCA (15 microM) over the spectral range 250 nm-340 nm (10 nm intervals) was determined.