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141.
142.

Background

Each year in the UK 2000 children attend emergency departments and 500 are admitted to hospital following a bath water scald. The long term effects can include disability, disfigurement or psychological harm and repeated skin grafts may be required as the child grows. The costs of treating a severe scald are estimated at 250,000 GBP. Children living in the most deprived wards are at greatest risk of thermal injuries; hospital admission rates are three times that for children living in the least deprived wards. Domestic hot water, which is usually stored at around 60 degrees Celsius, can result in a second-degree burn after 3 seconds and a third-degree burn after 5 seconds. Educational strategies to encourage testing of tap water temperature and reduction of hot water thermostat settings have largely proved unsuccessful. Legislation in the USA mandating pre-setting hot water heater thermostats at 49 degrees Celsius was effective in reducing scald injuries, suggesting passive measures may have a greater impact. Thermostatic mixer valves (TMVs), recently developed for the domestic market, fitted across the hot and cold water supply pipes of the bath, allow delivery of water set at a fixed temperature from the hot bath tap. These valves therefore offer the potential to reduce scald injuries.

Design/Methods

A pragmatic, randomised controlled trial to assess the effectiveness of TMVs in reducing bath hot tap water temperatures in the homes of families with young children in rented social housing. Two parallel arms include an intervention group and a control group where the intervention will be deferred. The intervention will consist of fitting a TMV (set at 44 degrees Celsius) by a qualified plumber and provision of educational materials. The control arm will not receive a TMV or the educational materials for the study duration but will be offered the intervention after collection of follow-up data 12 months post randomisation. The primary outcome measure will be the bath hot tap water temperature. Fifteen families per arm are required to detect a reduction in the mean bath hot tap water temperature from 60.4 degrees Celsius (SD 9.1) in the control group to 46 degrees Celsius in the intervention group, with 90% power and a 5% significance level (2 sided). Secondary outcome measures including acceptability will require a sample size of 120 participants.

Discussion

Whilst TMVs have the potential to reduce scald injuries, to date there have been no randomised controlled trials assessing their effectiveness, acceptability and cost effectiveness.

Trial Registration

ISRCTN21179067  相似文献   
143.
It has been hypothesized that disruption of circadian rhythms affects human health. Shift work and sleep deprivation are thought to disrupt the normal light–dark cycle, although the disruption due to shiftwork may be dependent on sleep deprivation. Both conditions have been suggested to be associated with an increased risk of cardiometabolic disorders. Non-photic environmental factors, such as the timing of eating, are also thought to regulate circadian rhythm and thus, may have effects on health, but the evidence from human studies is scarce. Oxidative stress is a risk factor of cardiometabolic disorders. Some laboratory studies suggest an involvement of circadian clock genes in the regulation of the redox system. The present study aimed to examine the association of sleeping habits, nightshift work, and the timing of meals with urinary levels of 8-isoprostane, a marker of oxidative stress, and 6-sulfatoxymelatonin, the principal metabolite of melatonin. Study subjects were 542 women who had previously attended a breast cancer mass screening in a community in Japan. Information on bedtimes and wake-up times, history of nightshift work, and the timing of meals was obtained by a self-administered questionnaire. The 8-isoprostane and 6-sulfatoxymelatonin were measured using the first morning void of urine and expressed per mg of creatinine. The geometric mean of 8-isoprostane levels was 12.1% higher in women with ≤6 hours of sleep than that in those with >8 hours of sleep on weekdays, and longer sleep duration on weekdays was significantly associated with lower urinary levels of 8-isoprostane after controlling for covariates (p for trend = 0.04). Women who were currently working the nightshift had a 33.3% higher geometric mean of 8-isoprostane levels than those who were not working nightshift (p = 0.03). Urinary 6-sulfatoxymelatonin levels were unrelated to sleep habits or nightshift work. Women who ate breakfast at irregular times had a 19.8% higher geometric mean of 8-isoprostane levels than those who ate breakfast at a regular time or who did not eat (p = 0.02). Women who ate nighttime snacks at irregular times had a 16.2% higher geometric mean of 8-isoprostane levels than those who did not eat nighttime snacks or who ate nighttime snacks at a regular time (p = 0.003). Among women who ate dinner at a regular time, earlier times for dinner were associated with higher 8-isoprostane and 6-sulfatoxymelatonin levels (p values for trends were 0.01 and 0.02, respectively). However, the times of dinner and nighttime snack are overlapping, and the time of last meal of the day was not associated with 8-isoprostane and 6-sulfatoxymelatonin levels. The time of breakfast or lunch was not associated with these biomarkers among women who ate the meal at regular times. Disturbing the rhythmicity of daily life may be associated with oxidative stress.  相似文献   
144.
Quercus crispula var. horikawae, a stunted shrub oak, occurs on mountains with deep snow on the Sea of Japan side of Japan. This oak generates patches of multiple creeping stems. It is unclear whether these patches are the result of asexual or sexual reproduction, or both. We therefore aimed to describe the clonal structure and gene flow in Q . crispula var. horikawae on Mount Nasu in central Japan by using nuclear microsatellites. Genotypes of 331 stems with no distinct connection with roots and creeping stems above the ground were determined using nine loci in two study plots, and 64 acorns from three mother genets in a plot were determined using eight loci. The results of the clonal identification indicated that the patches consisted of 51 genets; at least 85% of the stems may have been derived from asexual reproduction through sprouting and layering. The prominence of asexual reproduction may be a result of adaptation to the snowy environment. In contrast, 15% of the ramets in the study plots probably originate via sexual reproduction by seedling regeneration. Analyses of the spatial genetic structure and paternity showed that limited ability of the pollen and seeds to disperse might result in the spatial aggregations of closely related offspring at a relatively short distance (<10 m), and inbreeding, a factor that might reduce sexual reproduction, was not observed. Thus, sexual reproduction could be reduced by ecological rather than genetic factors, namely the hindrance of seedling regeneration by the dense coverage of dwarf bamboo (Sasa) on the forest floor.  相似文献   
145.
We isolated Cryptococcus sp. T1 from Lake Tazawa’s acidic water in Japan. Cryptococcus sp. T1 neutralized an acidic casamino acid solution (pH?3.0) and released ammonia from the casamino acids to aid the neutralization. The neutralization volume was estimated to be approximately 0.4 mL/h. The casamino acids’ amino acids decreased (1.24→0.15 mM); ammonia increased (0.22→0.99 mM). We neutralized acidic drainage water (1 L) from a Tamagawa River neutralization plant, which was run through the column with the T1-immobilized alginate beads at a flow rate of 0.5 mL/min, and observed that the viscosity, particle size and amounts of the alginate beads affected the acidic drainage neutralization with an increase of the pH value from 5.26 to 6.61 in the last fraction. An increase in the Al concentration decreased Cryptococcus sp. T1’s neutralization ability. After 48 h, the pH of acidic water with 50 mg/L Al was apparently lower than that without Al. Almost no pH increase was observed at 75 mg/L.  相似文献   
146.
147.
We previously generated mice lacking aromatase activity by targeted disruption of Cyp19 (ArKO mice), and reported phenotypes of the female mice, showing hemorrhage formation and follicular depletion in the ovary, diminution in uterine size, and bone loss. In the present study, we examined the influence of dietary bisphenol A (BPA), a monomer used for the production of polycarbonate and known to have estrogenic activity, on these phenotypes of the ArKO mice. When ArKO mice were fed chow diets supplemented with 0.1% or 1% (w/w) BPA for 5 months, they were protected from ovarian degeneration, uterine diminution and bone loss in a dose-dependent manner. Northern blot analyses of ovarian RNA of ArKO mice showed differences in the expression levels of insulin-like growth factor (IGF)-I, IGF-I receptor, growth differentiation factor 9 and bone morphogenetic protein 15 as compared with those in the ovaries of wild-type mice. The differences in the expression levels were restored by dietary BPA. In the ArKO uteri, expression of progesterone receptor and vascular endothelial growth factor mRNAs was diminished, and was restored by BPA to the levels in wild-type mice. In contrast, BPA had little effect on the ovarian, uterine and skeletal structures of wild-type mice. In conclusion, estrogenic effects of BPA on the reproductive tract as well as skeletal tissue were evident in adult female ArKO mice. These results suggest that the ArKO mouse is an animal model suitable for studying effects of estrogenic chemicals as well as estrogen in vivo.  相似文献   
148.
Imatinib (IMT), a specific tyrosine kinase inhibitor (TKI), has drastically changed the treatment strategy for Ph+ ALL (Philadelphia chromosome-positive acute lymphoblastic leukemia). However, TKI resistance remains a serious problem for patient prognosis. Here, a Ph+ ALL cell line NphA2 and the IMT-resistant subline NphA2/STIR were analyzed to identify a potential novel treatment strategy. We also examined other Ph+ ALL cells, MR87 and its IMT-resistant subline, MR87/STIR. IMT induced apoptosis of NphA2 and MR87 but had no effect on resistant sublines. Increased phosphorylated ERK and BCL2, but not BCL-XL, were observed in NphA2/STIR compared with NphA2. NphA2/STIR but not NphA2 was moderately sensitive to U0126, an ERK inhibitor. Interestingly, SP600125, a JNK inhibitor, was potent in cell growth inhibition and apoptosis induction of both parental and IMT-resistant NphA2 and MR87 cells. Moreover, NphA2 and MR87 and their IMT-resistant sublines were sensitive to ABT-199, a specific BCL2 inhibitor. The combination of SP600125 and ABT-199 synergistically suppressed both parental and IMT-resistant cells, including one with T315I mutation, suggesting that Ph+ ALL exhibits high sensitivity to ABT-199 and SP600125 regardless of TKI resistance. This combination might be a possible therapeutic strategy for Ph+ ALL in the future.  相似文献   
149.
150.
We determined that two siblings with type III osteogenesis imperfecta (OI) had the same single base substitution that converted the codon for glycine (Gly) 862 to a codon for serine (Ser) in exon 44 of the 1 chain of the type I ( 1(I)) collagen gene (COL1A1). The mutation was also detected in various paternal tissues; the mutant allele accounted for approximately 11% of the COL1A1 alleles in blood, 24% of those in fibroblasts, and 43% of those in sperm determined by allele-specific colony hybridization using amplified genomic sequences. These findings demonstrate that germ-line mosaicism in the phenotypically normal father is responsible for the recurrence. There is a cluster of serine substitutions for Gly (Gly832, Gly844 and Gly901) which is associated with nonlethal phenotypes and which is located between two lethal clusters. In the cases studied here, a Gly862Ser mutation was identified that is located inside the nonlethal cluster.  相似文献   
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