Central venous line sepsis in the intensive care unit. A study comparing antibiotic coated catheters with plain catheters

A randomized controlled clinical trial was undertaken to evaluate the efficacy of antibiotic bonded lines in the reduction of central venous catheter infection. One hundred and seventy-six plain and bonded catheters were inserted into one hundred and ten patients in an intensive care unit, many of whom were admitted with evidence of sepsis. The catheters used in the study group, which had been pre-treated by the manufacturers with the cationic surfactant tridodecylmethylammonium chloride, were bonded with vancomycin 1 g made up in 10 ml of water immediately prior to insertion. The catheters used in the control group were neither pre-treated nor bonded with vancomycin. Eighty percent of control group catheters were infected compared with 62% of study catheters (p = 0.01). The most common organism isolated was coagulase negative staphylococcus. We conclude that antibiotic bonding can reduce central venous catheter infection even in a patient population with a high incidence of sepsis.     

Endogenous carbon monoxide in control of respiration

CASE REPORT: A patient with recurrent breast cancer was reirradiated twice on adjacent fields with a time interval of 9 months. The first time she was treated with reirradiation alone, the second time with reirradiation plus hyperthermia. The reirradiation schedule for both fields was 8 x 4 Gy in 4 weeks. Both fields overlapped partly with the field of postoperative radiotherapy, which was applied 57 and 66 months earlier to a total dose of 40.5 Gy. RESULTS: During the 52 to 61 months follow-up, a remarkable difference in telangiectasia development, between the parts of the reirradiation fields overlapping with the primary radiotherapy field, became apparent. Telangiectasia was observed 9 months after treatment with reirradiation alone and progressed to confluent in 47 months after treatment. In the reirradiation plus hyperthermia area, the maximum observed telangiectasia was slight until 52 months after treatment. DISCUSSION: The difference in the development of telangiectasia between these fields cannot be explained by differences in any of the known radiation treatment related prognostic factors. A protective effect by hyperthermia has been suggested by Haveman and coworkers, who have shown experimentally that heat treatment leads to enhanced proliferation of endothelial cells, thereby inducing a fast repopulation and replacement of X-ray damaged cells. CONCLUSION: This difference in telangiectasia formation is an interesting observation. Whether such a protective effect of hyperthermia is of general relevance has to become clear from more extensive clinical studies.     

Pharmacokinetics, safety, and activity of nevirapine in human immunodeficiency virus type 1-infected children

The challenge of useful serial photographic documentation of hair loss can be met by using a regimented approach at each photographic session. Patient outcomes that are better documented allow for more informed decisions to be made about the course of therapy by both the physician and the patient.     

Effects of frusemide on the urinary excretion of dopamine and 5-hydroxytryptamine in normal man

The effects of frusemide on the urinary excretion of dopamine and 5-hydroxytryptamine (5-HT) were investigated in eight healthy male subjects in a randomized, placebo-controlled, cross-over study. Frusemide produced the expected rise in urinary dopamine excretion but it did not affect 5-HT excretion when compared with placebo. The lack of an effect on 5-HT excretion in man contrasts with studies in the rat which have reported a marked increase in 5-HT excretion after administration of this loop diuretic.     

Sequential bilateral adnexal torsion after a single cycle of gonadotropin ovulation induction with intrauterine insemination

As part of a programme for the implementation of a Smoking Control Policy in our hospital, an open study, without randomization, of 65 hospital workers, who wanted to give up smoking, was carried out. The characteristics of smoking in each subject were recorded. The Fagerstrom Questionnaire was used to measure the degree of dependence on nicotine. The treatment consisted of the daily use of 16 h nicotine patches for 12 weeks. During the first 4 weeks, the patches contained 15 mg of nicotine, for the second 4 weeks, 10 mg, and for the last 4 weeks 5 mg (per patch and day). Five visits were scheduled during the 26 week study period: at the start of the study and after 4, 8, 12 and 26 weeks. The abstinence was checked by measuring carbon monoxide in end-expiratory air. The success rate was 31% after 12 weeks, and decreased to 29% after 26 weeks. In conclusion, the nicotine patches appeared safe and effective in this study.     

The effects of intravenous antioxidants in patients with septic shock

Oxidative stress is implicated in septic shock. We investigated the effect of intravenous antioxidant therapy on antioxidant status, lipid peroxidation, hemodynamics and nitrite in patients with septic shock. Thirty patients randomly received either antioxidants (n-acetylcysteine 150 mg/kg for 30 min then 20 mg/kg/h plus bolus doses of 1 g ascorbic acid and 400 mg alpha-tocopherol) or 5% dextrose. Basal vitamin C was low and redox-reactive iron was elevated in all patients. In the 16 patients receiving antioxidants, vitamin C increased (p = .0002) but total antioxidant capacity was unaffected. Lipid peroxides were elevated in all patients but did not increase further in the patients receiving antioxidants. Plasma total nitrite also increased (p = .007) in the antioxidant group. Heart rate increased in patients receiving antioxidants at 60 min (p = .018) and 120 min (p = .004). Cardiac index also increased at 60 min (p = .007) and 120 min (p = .05). Systemic vascular resistance index decreased at 120 min in the antioxidant treated patients (p = .003). The effect of antioxidants on hemodynamic variables has not previously been reported. Antioxidant administration may be a useful adjunct to conventional approaches in the management of septic shock.     

Thermodynamics of dT--dT base pair mismatching in linear DNA duplexes and three-arm DNA junctions

We have used a combination of magnetic-suspension densimetry and calorimetry to derive complete thermodynamic profiles, including volume changes, for the formation of linear DNA duplexes and three-arm branched DNA junctions, from their component strands, with and without dT-dT mismatches. The formation of each type of complex at 20 degrees C is accompanied by a favorable free energy, with a favorable enthalpy term partially compensated by an unfavorable entropy. Formation is associated also with net uptake of water molecules. Using the formation of the fully-paired linear duplex or three-arm junction as reference states, we can establish a thermodynamic cycle in which the contribution of the single-strand species cancels. From this cycle, we determine that substitution of dA for dT has a differential free energy of deltadeltaG degrees of +2.4 kcal mol(-1) for mismatched duplex and +2.0 kcal mol(-1) (on the average) for the mismatched junction. These unfavorable differential free energies result from an unfavorable enthalpy, partially compensated by a favorable entropy, and a negative deltadeltaV. The free energies in the two cases have signs opposed to those of deltadeltaV, a situation that implicates hydration changes in creating the mismatch. When the deltadeltaV terms are normalized by the total number of base pairs involved, the immobilization of structural water molecules (and/or substitution of electrostricted for hydrophobic water molecules) is about 7 times greater for junctions than duplexes. This is consistent with more extensive hydrophobic hydration of branched DNA structures than of duplexes.     

In vivo electrochemical studies of dopamine clearance in subregions of rat nucleus accumbens: differential properties of the core and shell

The effects of the rodent hepatocarcinogens clofibric acid and diprofibrate on the activity of the peroxisomal fatty acyl-CoA oxidase, DNA synthesis, and apoptosis were compared in cultured rat and human hepatocytes. Rat hepatocytes expressed a 10-fold greater level of the peroxisomal fatty acyl-CoA oxidase compared to human hepatocytes. At the highest concentration (1.0 mM), both drugs induced a two- to threefold increase in this enzyme activity in both rat and human hepatocytes. Ciprofibrate (0.1 and 0.2 mM) caused a twofold increase in DNA synthesis in rat hepatocytes, whereas clofibric acid had no effect on DNA synthesis in these cells. In contrast, increasing concentrations of both clofibric acid and ciprofibrate produced inhibition of DNA synthesis in human hepatocytes. By using the terminal transferase dUTP-biotin nick end labeling technique, it was observed that 0.1 and 0.2 mM clofibric acid and ciprofibrate suppressed transforming growth factor-beta (TGF beta)-induced apoptosis by 50% in rat hepatocytes, but they had no effect on TGF beta-induced apoptosis in human hepatocytes. Although clofibric acid and ciprofibrate diminished TGF beta-induced apoptosis, they had no effect on the basal apoptotic levels in the rat hepatocyte cultures. However, both drugs significantly increased the percent of apoptotic cells in the human hepatocyte cultures. It is concluded that primary rat and human hepatocyte cultures respond differently to peroxisome proliferators. The differences in effects on DNA synthesis and apoptosis support the hypothesis that human liver cells are refractory to peroxisome proliferator-induced hepatocarcinogenesis.