An investigation of the microbiological contamination of ultrasound equipment

ltrasound equipment comes into direct contact with patients and practitioners during scanning procedures, enabling it to be a potential vehicle for the spread of nosocomial infections. A study was undertaken to determine the extent of contamination on this equipment and therefore the efficacy of the present decontamination guidelines.

Five ultrasound machines were sampled over a period of three months. Three used for non-invasive procedures and two for invasive procedures. The equipment was sampled from the probe, probe holder, keyboard and gel.

The results revealed that 64.5% of the total samples were contaminated with environmental organisms, 7.7% with potential pathogens and 27.8% were no growth. The most significant contamination was found on the non-invasive equipment, probably due to the lower level of decontamination practices designated for this equipment.

Following the study, comprehensive decontamination guidelines for all ultrasound equipment were devised and distributed to all ultrasound departments, and staff were educated on the need for improved decontamination regimes.

Values and public acceptability dimensions of sustainable egg production

The attributes of egg production that elicit values-based responses include the price and availability of eggs, environmental impacts, food safety or health concerns, and animal welfare. Different social groups have distinct interests regarding the sustainability of egg production that reflect these diverse values. Current scientifically based knowledge about how values and attitudes in these groups can be characterized is uneven and must be derived from studies conducted at varying times and using incomplete study methods. In general, some producer and consumer interests are translated through markets and are mediated by market mechanisms, whereas others are poorly reflected by economic behavior. An array of survey and focus group research has been performed to elicit consumer and activist beliefs about performance goals they would expect from an egg production system. These studies provide evidence that consumers' market behavior may be at odds with their ethical and political beliefs about performance goals.

Tomographic Small-Animal Imaging Using a High-Resolution Semiconductor Camera

We have developed a high-resolution, compact semiconductor camera for nuclear medicine applications. The modular unit has been used to obtain tomographic images of phantoms and mice. The system consists of a 64 x 64 CdZnTe detector array and a parallel-hole tungsten collimator mounted inside a 17 cm x 5.3 cm x 3.7 cm tungsten-aluminum housing. The detector is a 2.5 cm x 2.5 cm x 0.15 cm slab of CdZnTe connected to a 64 x 64 multiplexer readout via indium-bump bonding. The collimator is 7 mm thick, with a 0.38 mm pitch that matches the detector pixel pitch. We obtained a series of projections by rotating the object in front of the camera. The axis of rotation was vertical and about 1.5 cm away from the collimator face. Mouse holders were made out of acrylic plastic tubing to facilitate rotation and the administration of gas anesthetic. Acquisition times were varied from 60 sec to 90 sec per image for a total of 60 projections at an equal spacing of 6 degrees between projections. We present tomographic images of a line phantom and mouse bone scan and assess the properties of the system. The reconstructed images demonstrate spatial resolution on the order of 1-2 mm.

X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome is the human equivalent of mouse scurfy

To determine whether human X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome (IPEX; MIM 304930) is the genetic equivalent of the scurfy (sf) mouse, we sequenced the human ortholog (FOXP3) of the gene mutated in scurfy mice (Foxp3), in IPEX patients. We found four non-polymorphic mutations. Each mutation affects the forkhead/winged-helix domain of the scurfin protein, indicating that the mutations may disrupt critical DNA interactions.

Cardiology questions for the MRCP (UK) examination

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Myocardial infarction with extensive intracoronary thrombus induced by anabolic steroids

Anabolic steroids have been associated with a variety of adverse reactions, including myocardial infarction. We report two cases of myocardial infarction in young men on anabolic steroids. In both men, extensive intracoronary thrombosis was demonstrated at coronary angiography; this failed to resolve despite anticoagulation.

Myocardial infarction, hyperkalaemia and ventricular tachycardia in a young male body-builder

A 31-year-old body-builder taking anabolic steroids, amphetamines, frumil (frusemide and amiloride), and potassium supplements collapsed with a myocardial infarction. His serum potassium was 6.7 mmol/l and he had a run of ventricular tachycardia. He was unaware of the effects of the drugs on the heart.

Epidermal keratinocyte self-renewal is dependent upon dermal integrity

The epidermis is a major site of self-renewal in which there is constant replacement by cell division in the basal layers of cells lost by desquamation in the superficial layers. Such a tissue is therefore likely to contain stem cells and in this study we have examined the role of the dermis in the maintenance of epidermal self-renewal. We have developed a mouse model to address the question of whether the maintenance of epidermal self-renewal is dependent, as in the hemopoietic system, upon a heterologous cell type. Intact epidermis separated from dermis at the dermo-epidermal junction or epidermis derived from disaggregated epidermal cells, can reconstitute a stratified squamous epithelium when grafted onto the lumbo-dermal fascia of the mouse or onto an experimentally induced granulation tissue bed. However, we have shown that, after grafting, the clonogenic capacity of the keratinocytes declines sharply and the colonies that are produced are incapable of self-renewal in vitro. Although initially hyperplastic, these epidermal grafts assume an atrophic appearance after 40-70 d and this may be related to the loss of self-renewal observed in vitro. With both experimental murine grafts and clinical grafts the failure of keratinocytes to self-renew can be alleviated, partially, by the presence of the dermis in full-thickness or split-thickness grafts, which implies that the dermis has a functional role in epidermal stem cell maintenance. The relevance of these observations to the clinical experience with cultured autologous keratinocyte sheets as wound dressings to patients is discussed.

Properties of a non-tumorigenic human cervical keratinocyte cell line

A human cervical keratinocyte cell line, W12, has been initiated from a low-grade cervical lesion histologically diagnosed as CIN I. This cell line has, to date, undergone over 300 generations in vitro with an average doubling time of 30 hr: an aneuploid karyotype has developed with progressive in vitro growth. W12 contains HPV16 DNA present at approximately 100 copies and the state of the viral DNA over a number of passages has been examined. The HPV16 DNA is stably maintained at high copy number over several passages and restriction enzyme analysis together with electrophoresis of uncleaved viral DNA indicate that it is present predominantly as the episomal molecule. W12 cells exhibit a typical keratinocyte morphology and, when transplanted into the flank of the nude mouse, form an epithelial lesion with the histological features of CIN I/II.