Early rapid weight gain and current overweight in relation to asthma in adolescents born with very low birth weight

Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.     

Ropivacaine for dental anesthesia: a dose-finding study.

PURPOSE: The purpose of this study was to determine the optimal concentration and volumes of ropivacaine for dental anesthesia as regards onset and duration of action. SUBJECTS AND METHODS: Thirty healthy individuals with a mean age of 32 years participated in the study on a voluntary basis. All subjects received a ropivacaine injection in 1 of 3 randomized concentrations (2.0, 5.0, or 7.5 mg/mL) for infiltration anesthesia and mandibular nerve block in a double-blind manner. The onset time and duration of anesthesia were assessed by electric pulp test, pinprick test of the gingiva, and presence of feeling of numbness of the lip. RESULTS: Regardless of dose, only 5 patients received pulpal anesthesia after infiltration, but all 3 concentrations anesthetized the gingiva and upper lip. The onset of pulpal anesthesia occurred less than 5 minutes after injection and lasted for 4 to 58 minutes. Pinprick anesthesia lasted for 8 to 48 minutes, and numbness of the upper lip lasted 1 to 4 hours. The effectiveness of the mandibular nerve block with regard to pulpal anesthesia was dose dependent. Only ropivacaine at 7.5 mg/mL produced sufficient anesthesia. The onset of pulpal anesthesia occurred less than 10 minutes after injection and lasted for 2 to 6 hours. Pinprick anesthesia lasted for 3 to 6 hours and numbness of the lower lip lasted for 5 to 9 hours. CONCLUSION: This study shows that ropivacaine could be useful as a local anesthetic for mandibular nerve block in dentistry and that the very long duration of both pulpal and soft tissue anesthesia may be favorable in reducing postoperative pain.     

Radiographic prediction of failure after fixation of cervical hip fracture

During 1984-1985, 410 patients with cervical hip fracture were randomized between 2 methods of internal fixation-a single nail (Rydell) or 2 LIH hook pins (LIH). The patients were followed-up prospectively for at least 2 years. Radiographs were taken after 1 week, 1, 3, 6, 12, and 24 months. The radiographs of the 295 paients alive 2 years postoperatively were examined by one of the authors. The sliding and the diversion of the pins and the nail in the anteroposterior projection and the diversion in the lateral projection were measured. In the failure group (non-union, late segmental collapse), the greatest sliding was noted within 1 month postoperatively and the diversion increased up to 3 months. Significant differences between the failure and the non-failure groups could be seen even after 1 week. We also found that the degree of sliding of the LIH pins and the Rydell nail 1 month postoperatively is comparable to the scintigraphic pattern 2 weeks postoperatively in predicting failure after nternal fixation of cervical hip fractures.     

Sweden: growing interest in ethics

Lindahl's bibliographic essay highlights five books, two doctoral theses, and several journal articles that are Sweden's major contributions to the bioethics literature. The books are H. Fagerberg's edited work on medical ethics (1984), widely used as a textbook in Sweden's medical and nursing schools; G. Wretmark, A. Wretmark, and J. Ludvigsson's co-authored text on ethics in medical care (1983); physician A. Andrén-Sandberg's case book (1986); theologian B. Hanson's collection of essays (1988); and Fagerberg's edited work on the ethics of prenatal diagnosis (1980). The theses are C. Blomquist's (1971), the first in Sweden on medical ethics, and C. Kjellstrand's 1988 work on high technology medicine. The articles include two on medical ethics in Sweden written by Lindahl and published in issues of Theoretical Medicine, the only cited works in English.     

Demethylation of the Epstein-Barr virus origin of lytic replication and of the immediate early gene BZLF1 is DNA replication independent

Summary.  Epstein-Barr virus (EBV) episomal DNA is extensively methylated in Burkitt lymphoma derived cell lines. In this study we examined whether lytic viral cycle reactivation is dependent on demethylation of critical viral genes. Viral replication was induced in the Burkitt’s lymphoma cell line Daudi by the combination of 12-O-tetradecanoylphorbol-13-acetate (TPA) and sodium-butyrate. Two regions necessary for EBV replication, the BZLF1 immediate early region and the origin of lytic cycle replication (ori Lyt) were demethylated during the early phase of the lytic virus cycle. Demethylation was observed while production of new (unmethylated) viral DNA was blocked by phosphonoformic acid (PFA). This suggests that demethylation, which may be instrumental for the onset of the lytic cycle, is an active process independent of viral DNA repli- cation. Received February 13, 1999 Accepted June 30, 1999     

A new method for quantification of image distortion due to pile-up in scintillation cameras

Characterization of the count-rate performance of scintillation cameras should include not only the specification of count losses. At high count rates, there is also an image distortion due to the mispositioning of pile-up events. In this paper a simple and clinically relevant procedure to quantify this distortion is presented. The images of a square uniform technetium-99m phantom at high and low count rates are used. The fraction of the total counts being correctly positioned is determined as the peripheral count density divided by the total average count density. This ratio, corrected for the camera non-uniformity at low count rates, is called the positioning ability. According to the National Electrical Manufacturers' Association (NEMA), the system count rate performance with scatter should be reported as the measured count rate giving 20% count losses. In this paper it is suggested that this measure be complemented by a measure of the fraction correct positioned events at this count rate. This fraction, the high count rate positioning ability', can be easily and accurately measured using our method. The method has been tested on two different scintillation cameras. For one of them the high count rate positioning ability was determined as 91% at a measured count rate of 30000 s^–1 with 20% count losses. For the other camera, the corresponding figures were 88% at 59000 s^–1 and close to 100% at 38000 s^–1, before and after the installation of a new pile-up rejection circuit, respectively. Offprint requests to: C. Ceberg