Long-term accumulation and microdistribution of uranium in the bone and marrow of beagle dog

The accumulation and microdistribution of uranium in the bone and marrow of Beagle dogs were determined by both neutron activation and neutron-fission analysis. The experiment started immediately after the weaning period, lasting till maturity. Two animal groups were fed daily with uranyl nitrate at concentrations of 20 and 100 microg g(-1) food. Of the two measuring techniques, uranium accumulated along the marrow as much as in the bone, contrary to the results obtained with single, acute doses. The role played by this finding for the evaluation of radiobiological long-term risks is discussed. It was demonstrated, by means of a biokinetical approach, that the long-term accumulation of uranium in bone and marrow could be described by a piling up of single dose daily incorporation.     

Tissue response to a membrane of demineralized bovine cortical bone implanted in the subcutaneous tissue of rats

The treatment of persistent bone defects has encouraged the search for proper techniques or bone substitutes. In Dentistry, a common problem in the treatment of periodontal bone defects is the growth of tissues within the lesion, such as the junctional epithelium, which impair regeneration of these tissues. Guided tissue regeneration (GTR), based on the separation of the tissues by means of membranes or barriers, was developed in an attempt to improve periodontal regeneration. The aim of this study was to histologically evaluate the tissue response to a membrane of demineralized bovine cortical bone implanted in the subcutaneous tissue of rats. The study periods were 1, 3, 7, 15, 30 and 60 days after implantation. Analysis of the histological sections demonstrated a moderate to intense inflammatory response at 1 and 3 days, moderate at 7 and 15 days, and almost absent at 30 and 60 days. Resorption of the membrane began 15 days after implantation, and at 60 days only remnants could be detected in some animals. We concluded that the demineralized bovine cortical bone membrane was well tolerated by the tissues and is completely resorbed after 30-60 days by mononuclear cells and multinucleated giant cells, which disappear upon completion of the process.     

Laparoscopic treatment of adrenal diseases: 10 years on

Since it was initially described in 1992 laparoscopic adrenalectomy (LA) has been gaining popularity amongst urologists and its range of applications has progressively widened. Ten years after the first report of LA this type of operation is presently considered to be the 'standard of care' for most adrenal diseases requiring surgery. We define the current role of laparoscopy in the management of surgical adrenal diseases, using a Medline search (1997-2002) to assess reports of LA, focusing on indications, approaches (transperitoneal and retroperitoneoscopic) and comparative analyses, taking particular care to evaluate operative duration, rate of conversion and transfusion, complications and hospital stay. With both approaches LA is safe and effective and, when compared with open surgery, offers the same functional results with all the advantages of minimally invasive surgery. We conclude that LA based on either approach should be considered the treatment of choice for benign adrenal lesions. Although very promising, conservative surgery and LA should still be evaluated in cases of malignancy.     

Differential modulation of the immune response by breast- or formula-feeding of infants

Spontaneous integrin expression on CD4+, CD8+ and CD19+ lymphocytes at 6 months was significantly lower in breastfed than formula-fed infants ( p < 0.05). In another study of 59 formula-fed and 64 breastfed 12-month-old children blast transformation and cytokine production by lymphocytes, and T cell changes were measured before and after measles-mumps-rubella vaccination (MMR). Before vaccination, lymphocytes of breastfed children had lower levels of blast transformation without antigen ( p < 0.001), with tetanus toxoid ( p < 0.02) or Candida ( p < 0.04), and lower interferon-γ production ( p < 0.03). Fourteen days after the live viral vaccination, only the breastfed children had increased production of interferon-γ ( p < 0.02) and increased percentages of CD56+ ( p < 0.022) and CD8+ cells ( p < 0.004). These findings are consistent with a Thl type response by breastfed children, not evident in formula-fed children. Feeding mode has an important long-term immunomodulating effect on infants beyond weaning.     

Progression and Regression of Low-grade Epithelial Abnormalities of the Cervix

Summary: The records of 738 women with low-grade cervical epithelial abnormalities were examined for changes in degree of cervical disease and lesion size, as well as sociodemographic and behavioural factors which influence the development of invasive cancer of the cervix. Survival analysis was used to determine the predictors and rates of progression and regression. The results suggest that about 80% of low-grade epithelial abnormalities of the cervix will not progress within 2 years. The only predictors of progression were a biopsy diagnosis of CIN 1 and die size of the lesion. Predictors of regression were older age, older age at first intercourse, greater parity, fewer sexual partners, and absence of a past history of genital herpes. Although progression rates of low-grade abnormalities of the cervix were very low, CIN 1 lesions were 2.4 times (95% CI: 1.6 to 3.7) more likely to progress than lower-grade lesions and large lesions (>l/2 ectocervix) were 2.0 times (95% CI: 1.2 to 3.3) more likely to progress than small ones (相似文献   

Androgen responsive adult human prostatic epithelial cell lines immortalized by human papillomavirus 18

Prostate cancer and benign tumors of the prostate are the two most common neoplastic diseases in men in the United States, however, research on their causes and treatment has been slow because of the difficulty in obtaining fresh samples of human tissue and a lack of well characterized cell lines which exhibit growth and differentiation characteristics of normal prostatic epithelium. Non-neoplastic adult human prostatic epithelial cells from a white male donor were immortalized with human papillomavirus 18 which resulted in the establishment of the RWPE-1 cell line. Cells from the RWPE-1 cell line were further transformed by v-Ki-ras to establish the RWPE-2 cell line. The objectives of this study were to: (1) establish the prostatic epithelial origin and androgen responsiveness of RWPE-1 and RWPE-2 cell lines; (2) examine their response to growth factors; and (3) establish the malignant characteristics of the RWPE-2 cell line. Immunoperoxidase staining showed that both RWPE-1 and RWPE-2 cells express cytokeratins 8 and 18, which are characteristic of luminal prostatic epithelial cells, but they also coexpress basal cell cytokeratins. These cell lines show growth stimulation and prostate specific antigen (PSA) and androgen receptor (AR) expression in response to the synthetic androgen mibolerone, which establishes their prostatic epithelial origin. Both cell lines also show a dose-dependent growth stimulation by EGF and bFGF and growth inhibition when exposed to TGF-beta, however, the transformed RWPE-2 cells are less responsive. RWPE-1 cells neither grow in agar nor form tumors when injected into nude mice with or without Matrigel. However, RWPE-2 cells form colonies in agar and tumors in nude mice. In the in vitro invasion assay, RWPE-1 cells are not invasive whereas RWPE-2 cells are invasive. Nuclear expression of p53 and Rb proteins was heterogeneous but detectable by immunostaining in both cell lines. The RWPE-1 cells, which show many normal cell characteristics, and the malignant RWPE-2 cells, provide useful cell culture models for studies on prostate growth regulation and carcinogenesis.      

Communication development in Angelman's syndrome

The communication development in 11 children with Angelman's syndrome is described. The clinical observation that these children appear to have a greater ability with receptive rather than expressive language is investigated and these skills assessed using published communication schedules. In addition the understanding and the use of nonverbal communication such as natural gesture was studied. The data collected highlight the fact that these children have developed very few words and have difficulty in using gestural or sign systems. This has implications for speech and language therapists and the children's remedial programmes. Possible future longitudinal studies are suggested.     

Calcium, phosphorus, and magnesium concentrations in plasma during first week of life and their relation to type of milk feed

Serial changes in plasma levels of calcium, phosphorus, magnesium, alkaline phosphatase, and total proteins have been investigated in 138 healthy, term Caucasian infants. Blood samples were obtained for each infant from cord blood and on day 1 and day 6. The infants were studied in three groups according to whether they were breast fed, received 'Ostermilk No. 1' or 'Cow and Gate V' formulas. Levels of calcium, phosphorus, magnesium, alkaline phosphatase, and total proteins did not differ between the groups at birth or on day 1. By day 6 calcium levels were higher and phosphorus levels lower in the breast-fed infants compared with either of the artificially-fed groups. Phosphorus levels were lower in the V Formula group compared with the Ostermilk group but the mean calcium levels of these two groups did not differ significantly. However, only 2-8% of the V Formula group developed hypocalcaemia compared with 18-2% of the Ostermilk group. The only infant developing clinical tetany belonged to the group fed Ostermilk. Evidence is also given which suggests that those infants with low calcium levels on day 1 who were fed the high-solute milk tended to show a fall in calcium by day 6. This did not apply to the two other groups. It is concluded that the use of adapted cows' milk preparations for infant feeding should lead to a reduction in the incidence of neonatal tetany.     

The lateralising significance of hypergraphia in temporal lobe epilepsy

Six patients with hypergraphia and epilepsy are presented and their clinical features compared with other patients reported in the literature. It is suggested that hypergraphia occurs more frequently in patients with right-sided non-dominant temporal lobe lesions, in contrast for example to the schizophreniform presentation of left-sided lesions. Other features of psychopathology possibly associated with non-dominant lesions, including elation, hypereligiosity and déjà vu experiences, are also discussed.