Genetic basis of human testicular germ cell cancer: insights from the fruitfly and mouse

The prevalence of tumours of the germ line is increasing in the male population. This complex disease has a complex aetiology. We examine the contribution of genetic mutations to the development of germ line tumours in this review. In particular, we concentrate on fly and mouse experimental systems in order to demonstrate that mutations in some conserved genes cause pathologies typical of certain human germ cell tumours, whereas other mutations elicit phenotypes that are unique to the experimental model. Despite these experimental systems being imperfect, we show that they are useful models of human testicular germ cell tumourigenesis.

Microstructure and grain boundary microanalysis of X70 pipeline steel

Grain boundaries (GBs), particularly ferrite: ferrite GBs, of X70 pipeline steel were characterized using analytical electron microscopy (AEM) in order to understand its intergranular stress corrosion cracking (IGSCC) mechanism(s). The microstructure consisted of ferrite (alpha), carbides at ferrite GBs, some pearlite and some small precipitates inside the ferrite grains. The precipitates containing Ti, Nb, V and N were identified as complex carbo-nitrides and designated as (Ti, Nb, WC, N). The GB carbides occurred (1) as carbides along ferrite GBs, (2) at triple points, and (3) at triple points and extending along the three ferrite GBs. The GB carbides were Mn rich, were sometimes also Si rich, contained no micro-alloying elements (Ti, Nb, V) and also contained no N. It was not possible to measure the GB carbon concentration due to surface hydrocarbon contamination despite plasma cleaning and glove bag transfer from the plasma cleaner to the electron microscope. Furthermore, there may not be enough X-ray signal from the small amount of carbon at the GBs to enable measurement using AEM. However, the microstructure does indicate that carbon does segregate to alpha : alpha GBs during microstructure development. This is particularly significant in relation to the strong evidence in the literature linking the segregation of carbon at GBs to IGSCC. It was possible to measure all other elements of interest. There was no segregation at alpha : alpha GBs, in particular no S, P and N, and also no segregation of the micro-alloying elements, Ti, Nb and V. (C) 2003 Kluwer Academic Publishers.

Efficacy of a new self-supporting low-profile bednet for personal protection against Anopheles farauti (Diptera : Culicidae) in a village in Papua New Guinea

A new United States (U.S.) self-supporting low-profile bednet was designed by Walter Reed Army Institute of Research in collaboration with Breakthrough Technologies. The bednet incorporated permethrin-impregnated screening into a frame that erected automatically when removed from its bag. The new U.S. bednet was compared with the current Australian Defense Force (ADF) mosquito bednet at Buka Island, North Solomons Province, Papua New Guinea, in March 1999. At the time of the test, Anopheles farauti Laveran was the most abundant biting mosquito. Both bednet types provided > 97.8% protection compared with an unprotected collector. The untreated U.S. Army prototype bednet provided better protection than the untreated ADF bednet against mosquitoes entering the bednet during the night.

Measurement and prediction of energy expenditure in males during household and garden tasks

Participation in at least 30 min of moderate intensity activity on most days is assumed to confer health benefits. This study accordingly determined whether the more vigorous household and garden tasks (sweeping, window cleaning, vacuuming and lawn mowing) are performed by middle-aged men at a moderate intensity of 3-6 metabolic equivalents (METs) in the laboratory and at home. Measured energy expenditure during self-perceived moderate-paced walking was used as a marker of exercise intensity. Energy expenditure was also predicted via indirect methods. Thirty-six males [Xmacr (SD): 40.0 (3.3) years; 179.5 (6.9) cm; 83.4 (14.0) kg] were measured for resting metabolic rate (RMR) and oxygen consumption (V.O-2) during the five activities using the Douglas bag method. Heart rate , respiratory frequency, CSA (Computer Science Applications) movement counts, Borg scale ratings of perceived exertion and Quetelet's index were also recorded as potential predictors of exercise intensity. Except for vacuuming in the laboratory, which was not significantly different from 3.0 METs (P=0.98), the MET means in the laboratory and home were all significantly greater than 3.0 (Pless than or equal to0.006). The sweeping and vacuuming MET means were significantly higher (P

Behavioural characterization of Vitamin D receptor knockout mice

Vitamin D (calcitriol) is a nuclear transcription regulator acting via a nuclear hormone receptor (VDR). In addition to its role in the regulation of calcium and phosphate horneostasis and in bone formation, Vitamin D is also thought to be involved in brain function. The aim of this study was to behaviourally phenotype VDR knockout mice. We characterized the behaviour of VDR null mutant mice and wildtype littermate controls by subjecting them to a range of tests including a primary behavioural screen (using the SHIRPA protocol), rotarod, gait analysis, Y-maze, marble burying test, bedding test, holeboard test, elevated plus maze, open field test and prepulse inhibition of the acoustic startle response. There were no effects of genotype on most of the scores from the SHIRPA protocol except that VDR -/- mice had alopecia, were shorter and weighed less than VDR +/+ mice. VDR -/- mice had a shorter gait as well as impairments on the rotarod, in the bedding test and impaired habituation in both the open field and on the acoustic startle response. The VDR -/- mice had normal acoustic startle responses but had impaired PPI at long (256 ms) but not short (64 ms) prepulse to pulse intervals. The VDR -/- mice were less active in the open field and buried fewer marbles in the marble burying test. However, there were no differences in the time spent on the open arms of the elevated plus maze or in working memory as assessed by repeat arm entries on the Y-maze. Therefore, it appears that VDR -/- mice have muscular and motor impairments that significantly affects locomotor behaviour but seemingly no impairments in cognition as indicated by exploration, working memory or anxiety. (C) 2004 Elsevier B.V. All rights reserved.

The effect of positive end-expiratory pressure level on peak expiratory flow during manual hyperinflation

Including positive end-expiratory pressure (PEEP) in the manual resuscitation bag (MRB) may render manual hyperinflation (MHI) ineffective as a secretion maneuver technique in mechanically ventilated patients. In this study we aimed to determine the effect of increased PEEP or decreased compliance on peak expiratory flow rate (PEF) during MHI. A blinded, randomized study was performed on a lung simulator by 10 physiotherapists experienced in MHI and intensive care practice. PEEP levels of 0-15 cm H2O, compliance levels of 0.05 and 0.02 L/cm H2O, and MRB type were randomized. The Mapleson-C MRB generated significantly higher PEF (P < 0.01, d = 2.72) when compared with the Laerdal MRB for all levels of PEEP. In normal compliance (0.05 L/cm H2O) there was a significant decrease in PEF (P < 0.01, d = 1.45) for a PEEP more than 10 cm H2O in the Mapleson-C circuit. The Laerdal MRB at PEEP levels of more than 10 cm H2O did not generate a PEF that is theoretically capable of producing two-phase gas-liquid flow and, consequently, mobilizing pulmonary secretions. If MHI is indicated as a result of mucous plugging, the Mapleson-C MRB may be the most effective method of secretion mobilization.

Effectiveness of topical skin care provided in aged care facilities

Background The 2001 Australian census revealed that adults aged 65 years and over constituted 12.6% of the population, up from 12.1% in 1996. It is projected that this figure will rise to 21% or 5.1 million Australians by 2031. In 1998, 6% (134 000) of adults in Australia aged 65 years and over were residing in nursing homes or hostels and this number is also expected to rise. As skin ages, there is a decreased turnover and replacement of epidermal skin cells, a thinning subcutaneous fat layer and a reduced production of protective oils. These changes can affect the normal functions of the skin such as its role as a barrier to irritants and pathogens, temperature and water regulation. Generally, placement in a long-term care facility indicates an inability of the older person to perform all of the activities of daily living such as skin care. Therefore, skin care management protocols should be available to reduce the likelihood of skin irritation and breakdown and ultimately promote comfort of the older person. Objectives The objective of this review was to determine the best available evidence for the effectiveness and safety of topical skin care regimens for older adults residing in long-term aged care facilities. The primary outcome was the incidence of adverse skin conditions with patient satisfaction considered as a secondary outcome. Search strategy A literature search was performed using the following databases: PubMed (NLM) (1966–4/2003), Embase (1966–4/2003), CINAHL (1966–4/2003), Current Contents (1993–4/2003), Cochrane Library (1966–2/2003), Web of Science (1995–12/2002), Science Citation Index Expanded and ProceedingsFirst (1993–12/2002). Health Technology Assessment websites were also searched. No language restrictions were applied. Selection criteria Systematic reviews of randomised controlled trials, randomised and non-randomised controlled trials evaluating any non-medical intervention or program that aimed to maintain or improve the integrity of skin in older adults were considered for inclusion. Participants were 65 years of age or over and residing in an aged care facility, hospital or long-term care in the community. Studies were excluded if they evaluated pressure-relieving techniques for the prevention of skin breakdown. Data collection and analysis Two independent reviewers assessed study eligibility for inclusion. Study design and quality were tabulated and relative risks, odds ratios, mean differences and associated 95% confidence intervals were calculated from individual comparative studies containing count data. Results The resulting evidence of the effectiveness of topical skin care interventions was variable and dependent upon the skin condition outcome being assessed. The strongest evidence for maintenance of skin condition in incontinent patients found that disposable bodyworn incontinence protection reduced the odds of deterioration of skin condition compared with non-disposable bodyworns. The best evidence for non-pressure relieving topical skin care interventions on pressure sore formation found the no-rinse cleanser Clinisan to be more effective than soap and water at maintaining healthy skin (no ulcers) in elderly incontinent patients in long-term care. The quality of studies examining the effectiveness of topical skin care interventions on the incidence of skin tears was very poor and inconclusive. Topical skin care for prevention of dermatitis found that Sudocrem could reduce the redness of skin compared with zinc cream if applied regularly after each pad change, but not the number of lesions. Topical skin care on dry skin found the Bag Bath/Travel Bath no-rinse skin care cleanser to be more effective at preventing overall skin dryness and most specifically flaking and scaling when compared with the traditional soap and water washing method in residents of a long-term care facility. Information on the safety of topical skin care interventions is lacking. Therefore, because of the lack of evidence, no recommendation on the safety on any intervention included in this review can be made.

A systematic review of topical skin care in aged care facilities

This systematic review aimed to evaluate the best available evidence regarding the effectiveness of topical skin care interventions for residents of aged care facilities. Introduction. Natural changes to skin, as well as increased predisposition to pressure sores and incontinence, means residents of aged care facilities readily require topical skin care. A range of interventions exist that aim to maintain or improve the integrity of skin of older adults. Methods. Pubmed, Embase, Current Contents, CINAHL and The Cochrane Library databases were searched, as well as Health Technology Assessment websites up to April 2003. Systematic reviews and randomized or non-randomized controlled trials were evaluated for quality and data were independently extracted by two reviewers. Results. The effectiveness of topical skin interventions was variable and dependent on the skin condition being treated. Studies examined the effectiveness of washing products on incontinence irritated skin. Disposable bodyworns may prevent deterioration of skin condition better than non-disposable underpads or bodyworns. Clinisan, a no-rinse cleanser may reduce the incidence of incontinence associated pressure ulcers when compared with soap and water. Conclusion. In general the quality of evidence for interventions to improve or maintain the skin condition in the older person was poor and more research in this area is needed. Relevance to Clinical Practice. Skin care is a major issue for nurses working with older people. On the basis of this review no clear recommendations can be made. This lack of strong evidence for nurses to base effective practice decisions is problematic. However, the 'best' evidence suggests that disposable bodyworns are a good investment in the fight against skin deterioration. No rinse cleansers are to be preferred over soap and the use of the bag bath appears to be a useful practice to reduce the risk of dry skin ( a risk factor for breaches in skin integrity).