Mechanism of Pseudomonas aeruginosa persistence during treatment with broad-spectrum cephalosporins of lung infections in patients with cystic fibrosis.

Beta-lactam resistance in Pseudomonas aeruginosa detected only during ceftazidime therapy of cystic fibrosis patients was studied. Evaluation of resistant and susceptible isolates from one patient and resistant laboratory derivatives indicated that elevated beta-lactamase levels were the primary determinant of resistance. Susceptible isolates outgrew resistant isolates on antibiotic-free medium.     

The Stanford experience with combined procarbazine, Alkeran and vinblastine (PAVe) and radiotherapy for locally extensive and advanced stage Hodgkin's disease.

This report describes the efficacy and toxicity of PAVe (procarbazine, Alkeran, vinblastine) and irradiation (RT) in the management of 159 patients with locally extensive or advanced stage Hodgkin's disease (HD) at Stanford University. Patients received six courses of chemotherapy alternating with RT. The extent of RT and the schedule of treatment varied according to the stage of disease. About 2/3 of patients received PAVe/RT in the setting of prospective, randomized clinical trials. The rate of complete response was 93%. With a median follow-up of seven years (range 2-17), the 15 year actuarial freedom from progression (FFP) is 78% and overall survival is 75%. Ten-year FFP by stage is: 80% for locally extensive stage II, 90% for stage IIIA and 70% for stage IIIB. Excellent and equal results were attained with PAVe/RT vs. MOP(P) (mustard, Oncovin, procarbazine with or without prednisone)/RT in the randomized combined modality studies. Progression or recurrence was documented in 30 patients and was more common in irradiated sites. PAVe was well tolerated acutely. There were no treatment related fatalities. Twenty-three (14%) patients were admitted to the hospital for neutropenic fever. Five second malignancies have occurred after PAVe/RT only: one myelodysplastic syndrome, one acute myelogenous leukemia, one non-Hodgkin's lymphoma and two solid tumors including a case of non-small cell lung cancer and an in situ carcinoma of the cervix. Three patients died from myocardial infarction several years after the completion of treatment. These mature data show that PAVe/RT is effective and well-tolerated therapy for locally extensive stage II and IIIA/B HD.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of finishing time on marginal sealing ability of new generation composite bonding systems

Although variation in finishing techniques has been shown to affect microleakage, little research has been published on the influence of finishing time on the marginal sealing ability of new generation composite bonding systems. The objective of the present study was to evaluate the influence of finishing time on the enamel and dentine marginal sealing ability of four new generation composite systems. Two class V preparations, which were solely in enamel or dentine, were made on the buccal surfaces of 96 freshly extracted molar teeth. The teeth were randomly divided into four groups of 24 and restored with composite resin (Silux Plus^®) utilizing the following bonding systems: Scotchbond Multi-purpose^®, Fuji Bond LC^®, Prime & Bond 2·0^® and Bisco One-step^®. Half of the restorations in each group were finished immediately after light polymerization and stored for 1 week. For the remaining restorations, finishing was delayed for 1 week. The storage medium was isotonic saline at 37°C throughout the experiment. All restorations were then thermocycled, subjected to dye penetration testing, sectioned and scored. The results suggest that the finishing of composite restorations, bonded with the bonding systems evaluated, should be carried out immediately after light polymerization. Delayed finishing does not improve but instead can be detrimental to the marginal seal of the restorations. The effects of delayed finishing are, however, both bonding system and tissue specific.     

Partial k-space reconstruction in single-shot diffusion-weighted echo-planar imaging.

Partial k-space sampling is frequently used in single-shot diffusion-weighted echo-planar imaging (DW-EPI) to reduce the TE and thereby improve the SNR. However, it increases the sensitivity of the technique to bulk rotational motion, which introduces a phase gradient across the tissue that shifts the echo in k-space. If the echo is displaced into the high spatial frequencies, conventional homodyne reconstruction fails, causing intensity oscillations across the image. Zero-padding, on the other hand, compromises the image resolution and may cause truncation artifacts. We present an adaptive version of the homodyne algorithm that detects the location of the echo in k-space and adjusts the center and width of the homodyne filters accordingly. The adaptive algorithm produces artifact-free images when the echo is shifted into the high positive k-space range, and reduces to the standard homodyne algorithm in the absence of bulk motion.     

Association of HLA-DQA1*03011-DQB1*0301 haplotype with the development of respiratory scleroma.

OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS.     

Muscle strength in healthy white and Asian subjects: the relationship of quadriceps maximum voluntary contraction to age, sex, body build and vitamin D

1. The maximum voluntary isometric contraction (MVC) of the dominant quadriceps muscle was measured in 136 healthy White and 172 healthy Hindu Asian subjects resident in London, using a specially designed chair equipped with a force measuring load cell. 2. Males were stronger than females, and for both sexes MVC declined with age. From age 20 to 60 the annual decline in MVC ranged from 0.56% in White males to 1.5% in female Asians. 3. White subjects were stronger than Asian subjects even after correcting for the effect of age, height, weight and sex in a multi-factorial analysis. 4. Only in males did MVC correlate with height and weight. Asian women were more obese than any other group, and showed an increase in body mass index with age. 5. Twenty-two per cent of Asian subjects had marked vitamin D deficiency (plasma 25-hydroxycholecalciferol less than 10 nmol/1). There was no correlation between MVC, and plasma 25-hydroxycholecalciferol.     

Physico-chemical characterisation of rinderpest virus

Rinderpest virus grown in Vero cells was purified by equilibrium sedimentation in potassium tartrate gradients. The characteristics of the virus and its RNA dependend on the passage history of the virus. Undiluted passage virus had a density ofc 1.21 g/ml in potassium tartrate and contained RNA sedimenting atc. 20S and 5S. Virus obtained by dilute passage had a density ofc. 1.24 g/ml and contained 50S in addition to 20S and 5S RNA. Both diluted passage and undiluted passage viruses contained polypeptides with molecular weights of 98, 79, 75, 66, 48, 43 and 37×10³. Trace amounts of polypeptides with molecular weights of 29 and 20×10³ were also detected. The molecular weights of the major polypeptides are similar to those of the polypeptides present in measles and canine distemper viruses.