Randomized trial of the addition of gram-positive prophylaxis to standard antimicrobial prophylaxis for patients undergoing autologous bone marrow transplantation

The purpose of the study reported here was to investigate the impact of prophylaxis against gram-positive infections in patients undergoing high-dose chemotherapy and autologous bone marrow transplantation in a randomized trial. Forty-three patients undergoing high-dose chemotherapy with autologous bone marrow transplant were enrolled in a nonblinded randomized trial to receive or not to receive prophylaxis for gram-positive infections with 10(6) U of penicillin intravenously (i.v.) every 6 h (q6h) (if penicillin allergic, 750 mg of vancomycin i.v. q12h) in addition to standard antimicrobial prophylaxis with 400 mg of norfloxacin orally three times a day, 200 mg of fluconazole orally once a day, and 5 mg of acyclovir per kg of body weight i.v. q12h. The patients were being treated for germ cell cancer (n = 15), breast cancer (n = 16), Hodgkin's disease (n = 3), non-Hodgkin's lymphoma (n = 4), acute myeloid leukemia (n = 1), acute lymphoblastic leukemia (n = 1), and ovarian cancer (n = 3). The trial was stopped because of excess morbidity in the form of streptococcal septic shock in the group not receiving gram-positive prophylaxis. There were significantly fewer overall infections (10 versus 3; P = 0.016) and streptococcal infections (9 versus 1; P = 0.0078) in the group receiving gram-positive prophylaxis. There were no significant differences in the numbers of deaths, duration of broad-spectrum antibiotics, or incidence of neutropenic fever between the two groups. Prophylaxis for gram-positive infections with penicillin or vancomycin is effective in reducing the incidence of streptococcal infections in patients undergoing high-dose chemotherapy and autologous bone marrow transplant. However, this approach may carry a risk of fostering resistance among streptococci to penicillin or vancomycin.     

Evaluation of the role of the Yersinia pestis plasminogen activator and other plasmid-encoded factors in temperature-dependent blockage of the flea

Yersinia pestis, the plague bacillus, has a plasminogen activator (pla) gene on the 9.5-kb plasmid pPla that is hypothesized to play a role in producing the foregut blockage in the flea vector that precedes transmission. In this study, however, Y. pestis that lacked pPla, the 70-kb virulence plasmid, or both plasmids, proved able to block Xenopsylla cheopis fleas normally. Blockage rates decreased with increasing environmental temperature for fleas infected with either wild type or pPla- Y. pestis. Thus, procoagulant ability of the Y. pestis pla gene product does not mediate blockage, nor does its ability to induce fibrinolysis at>28 degreesC account for failure to block at elevated temperatures. A Y. pestis strain that lacked all or part of the third plasmid of 110 kb, however, failed to colonize the flea midgut normally, indicating that one or more genes on the large plasmid may be required for vectorborne transmission.     

Percutaneous aspiration liver biopsy using a large-caliber disposable needle: a preliminary report

A modification of the aspiration liver biopsy technique using a large-caliber disposable needle is described in an 18-month experience. One hundred forty liver biopsies were performed, obtaining adequate tissue in 98% of the patients. Complications occurred in 12 patients and were limited to pain at the biopsy site, epigastrium, or right shoulder; one instance of tachycardia and three of transient hypotension occurred. Thirty patients studied prospectively with liver scans and hematologic parameters failed to disclose subclinical complications. While the number of patients biopsied is still too small to provide definite conclusions , it appears that this technique is safe, similar and has a very high yield of excellent specimens. In addition, the needle offers the advantage of being disposable and easy to use by a single operator.     

Impedance properties of a longitudinal slot antenna in the broad face of a rectangular waveguide

The impedance properties of a waveguide longitudinal slot antenna of arbitrary length and offset in guide walls of finite thickness are investigated. These properties are obtained by treating the slot discontinuity as an electromagnetic boundary value problem and the resulting pair of coupled integral equations are solved by numerical techniques. Results are given for slots having lengths from0.35lambdato1.7lambdaand are in good agreement with experimental results.     

Experimentally-induced osteoarthritis in guinea pigs: effect of surgical procedure and dietary intake of vitamin C

The effect of variation in dietary ascorbic acid on surgically induced osteoarthritis was examined in the stifle joints of guniea pigs. Two different surgical procedures were used to induce osteoarthritis in the right stifle joint of these animals. Guinea pigs were maintained either on a high (150 mg/day) or low (2.4 mg/day) dietary intake of vitamin C. Regardless of the surgical procedure used to induce osteoarthritis, the animals maintained on the high level of vitamin C consistently showed severe joint damage than animals on the low level of the vitamin.     

Effect of dietary zinc levels on health and productivity of gilts and sows through two parities

The influence of 0, 50, 500 or 5,000 ppm supplemental Zn on productive characteristics, weight change, and serum and organ mineral concentrations of 60 crossbred and purebred Yorkshire gilts was evaluated. Gilts were fed their respective treatment from 30 kg body weight until the completion of two parities. Sows fed 5,000 ppm supplemental Zn weighed significantly less than sows from the other treatments when killed. Serum alkaline phosphatase activity was higher for the sows fed the highest level of Zn in all replications at 10 and 14 mo of age than for sows from the other treatments. Sows fed 0, 50 or 500 ppm had lower serum Zn and higher serum Cu concentrations than sows fed 5,000 ppm Zn at 10 and 14 mo of age. The number of pigs farrowed (total and live) and birth weight were not affected by dam's dietary treatment. However, sows receiving no additional Zn had a higher number of abnormal pigs/litter than sows on the other treatments. Sows fed 5,000 ppm additional Zn weaned fewer pigs that weighed less at weaning than sows on the other treatments. The concentration of Zn in the sow's liver increased significantly and liver Cu decreased as dietary level of Zn increased. Sows receiving 5,000 ppm Zn had lower hepatic Fe stores compared with sows receiving 500 ppm Zn. Elevated renal Cu and Zn concentrations were found in sows fed the highest level of Zn supplementation. The Zn concentration was higher and the Cu concentration lower in the aorta of sows fed 5,000 ppm Zn compared with sows fed 0 or 50 ppm additional Zn. Incidence of osteochondrosis was higher in sows supplemented with 5,000 ppm Zn than for sows from the other treatments.