Models of dengue virus infection

The need for models of dengue disease has reached a pinnacle as the transmission of this mosquito-borne virus has increased dramatically. Little is known about the mechanisms that lead to dengue fever and its more severe form, dengue hemorrhagic fever; this is owing to the fact that only humans show signs of disease. In the past 5 years, research has better identified the initial target cells of infection, and this has led to the development of models of infection in primary human cell cultures. Mouse-human chimeras, containing these target cells, have also led to progress in developing animal models. These advances should soon end the stalemate in testing antivirals and vaccine preparations that had necessarily been done in incomplete or irrelevant models.     

Meta-analysis of genome-wide scans provides evidence for sex- and site-specific regulation of bone mass.

Several genome-wide scans have been performed to detect loci that regulate BMD, but these have yielded inconsistent results, with limited replication of linkage peaks in different studies. In an effort to improve statistical power for detection of these loci, we performed a meta-analysis of genome-wide scans in which spine or hip BMD were studied. Evidence was gained to suggest that several chromosomal loci regulate BMD in a site-specific and sex-specific manner. INTRODUCTION: BMD is a heritable trait and an important predictor of osteoporotic fracture risk. Several genome-wide scans have been performed in an attempt to detect loci that regulate BMD, but there has been limited replication of linkage peaks between studies. In an attempt to resolve these inconsistencies, we conducted a collaborative meta-analysis of genome-wide linkage scans in which femoral neck BMD (FN-BMD) or lumbar spine BMD (LS-BMD) had been studied. MATERIALS AND METHODS: Data were accumulated from nine genome-wide scans involving 11,842 subjects. Data were analyzed separately for LS-BMD and FN-BMD and by sex. For each study, genomic bins of 30 cM were defined and ranked according to the maximum LOD score they contained. While various densitometers were used in different studies, the ranking approach that we used means that the results are not confounded by the fact that different measurement devices were used. Significance for high average rank and heterogeneity was obtained through Monte Carlo testing. RESULTS: For LS-BMD, the quantitative trait locus (QTL) with greatest significance was on chromosome 1p13.3-q23.3 (p = 0.004), but this exhibited high heterogeneity and the effect was specific for women. Other significant LS-BMD QTLs were on chromosomes 12q24.31-qter, 3p25.3-p22.1, 11p12-q13.3, and 1q32-q42.3, including one on 18p11-q12.3 that had not been detected by individual studies. For FN-BMD, the strongest QTL was on chromosome 9q31.1-q33.3 (p = 0.002). Other significant QTLs were identified on chromosomes 17p12-q21.33, 14q13.1-q24.1, 9q21.32-q31.1, and 5q14.3-q23.2. There was no correlation in average ranks of bins between men and women and the loci that regulated BMD in men and women and at different sites were largely distinct. CONCLUSIONS: This large-scale meta-analysis provided evidence for replication of several QTLs identified in previous studies and also identified a QTL on chromosome 18p11-q12.3, which had not been detected by individual studies. However, despite the large sample size, none of the individual loci identified reached genome-wide significance.     

Forearm bone mass and biochemical markers of bone remodelling in normal Chinese women

We studied bone mineral content and density (BMC/BMD) and bone turnover markers in normal Chinese women from the age of 20 to 80 years and compared the data with those for normal women from the Western part of the world (Denmark). In all subjects (5 at each age;n=305) BMC and BMD were determined at three sites of the nondominant forearm with single X-ray absorptiometry (SXA). In addition, 10 women had five repeated measurements to determine the reproducibility of the equipment, demonstrating coefficients of variation of 1%–2% depending on the measurement site. The Chinese premenopausal women were on the average heavier (1 kg) than the postmenopausal women, but they were also taller (6 cm). The postmenopausal women had highly significantly less bone mass than the premenopausal women; 15% at the 1/4-distal site, 25% at the 8-mm-distal site, and 35% at the ultradistal site. At age 50, bone mass in Chinese women was very similar to that of a comparable group of Danish women. After age 50, bone loss accelerated and the rate of loss seemed more rapid in the Chinese than in the Danish women. Within the first 5 postmenopausal years, the most cortical part decreased by approximately 3.9%, the mixed cortical and trabecular site by 9.5%, and the mainly trabecular site by 16.2%. In the following 5 years the decreases were 6.3%, 5.5%, and 6.6%, respectively, and 5.6%, 11.3%, and 8.9% for year 11–15 after menopause. The bone decrement continued throughout the 25th year of menopause, and except for the ultradistal site, the rate of loss did not change very much. The postmenopausal women had highly significantly higher levels of all bone turnover markers than premenopausal women. The markers stayed high at all ages. We conclude that the present study gives the normal values of Chinese women's bone mass at three sites of the distal forearm. The data were collected in a way which allows them to be used as reference for normal Chinese women. The data demonstrate that women from the East and West are relatively similar in terms of bone mass.     

Housing and service for the elderly in Denmark

During the past fifteen years, Denmark has been forced to develop new attitudes towards old age and new ways of housing and servicing the elderly, due not only to the increasing number of elderly but also because of societal change. Institutional care is insufficient, and nursing homes are no longer built. “Staying home as long as possible” is the policy, supported by flexible and efficient home help service and nursing care, which is given to all according to their needs, free of charge. Every elderly person has the right to independent living. In accordance with the Housing Act for the Elderly, which sets a standard for a self-contained dwelling, a variety of housing is being built, ranging from co-housing with opportunities for mutual support and exchange of resources among the elderly themselves to special housing for frail elderly. Denmark will face the next boom of elderly in about fifteen years. To ensure that elderly people can live independent lives, using their own resources, the challenges ahead are to remove the societal barriers hindering independent living, to develop a greater variety of housing options and to ensure access to services. The housing and care policy for the elderly depends on the view of old age and the chosen model of ageing.     

Oral mucosal side effects of cytotoxic chemotherapy of testicular cancer. A retrospective study

Cancer chemotherapy often leads to injury of normal cells. Adverse effects on oral mucosa have been documented for several cytotoxic treatment regimens. The aim of the present retrospective study was to evaluate incidence and degree of oral soft tissue side-effects of a cisplatin-based chemotherapy regimen used for treating testicular cancer. The study was based upon a questionnnaire mailed to 56 consecutive patients treated at the Norwegian Radium Hospital. A total of 39 individuals joined the study, as 2 patients refused and 15 did not reply. The patients were divided into two groups, a case group (24 individuals) having received 4-7 cycles of cisplatin-based chemotherapy in addition to surgery, and a control group (15: individuals) treated with surgery alone. The study revealed that 62% of the patients in the chemotherapy group developed adverse soft tissue reactions, with mucositis and pain as chief complaints, whereas none in the control group experienced any mucosal complications.     

Exposure to ammonia and acute respiratory effects in a urea fertilizer factory

Personal exposures to ammonia and acute respiratory effects were determined in workers at a urea fertilizer factory in Bangladesh. Full-shift personal exposure to ammonia was measured using a PAC III direct reading instrument and Drager diffusion tubes. Respiratory symptoms were elicited by a questionnaire study (n = 113), and preshift and postshift lung function (FVC, FEV1, and PEFR) were tested using spirometry (n = 88). Urea plant workers had higher mean exposure to ammonia and prevalence of acute respiratory symptoms than did workers in the ammonia plant. The symptoms with highest prevalence in the urea plant were chest tightness (33%) and cough (28%). FVC and FEV1 decreased significantly across the work shift among urea plant workers. The higher level of exposure to ammonia in the urea plant was associated with an increased prevalence of respiratory symptoms and an acute decline in lung function.