IpaC from Shigella and SipC from Salmonella possess similar biochemical properties but are functionally distinct

Invasion plasmid antigen C (IpaC) is secreted via the type III secretion system (TTSS) of Shigella flexneri and serves as an essential effector molecule for epithelial cell invasion. The only homologue of IpaC identified thus far is Salmonella invasion protein C (SipC/SspC), which is essential for enterocyte invasion by Salmonella typhimurium. To explore the biochemical and functional relatedness of IpaC and SipC, recombinant derivatives of both proteins were purified so that their in vitro biochemical properties could be compared. Both proteins were found to: (i) enhance the entry of wild-type S. flexneri and S. typhimurium into cultured cells; (ii) interact with phospholipid membranes; and (iii) oligomerize in solution; however, IpaC appeared to be more efficient in carrying out several of the biochemical properties examined. Overall, the data indicate that purified IpaC and SipC are biochemically similar, although not identical with respect to their in vitro activities. To extend these observations, complementation analyses were conducted using S. flexneri SF621 and S. typhimurium SB220, neither of which is capable of invading epithelial cells because of non-polar null mutations in ipaC and sipC respectively. Interestingly, both ipaC and sipC restored invasiveness to SB220 whereas only ipaC restored invasiveness to SF621, suggesting that SipC lacks an activity possessed by IpaC. This functional difference is not at the level of secretion because IpaC and SipC are both secreted by SF621 and it does not appear to be because of SipC dependency on this native chaperone as coexpression of sipC and sicA in SF621 still failed to restore detectable invasiveness. Taken together, the data suggest that IpaC and SipC differ in either their ability to be translocated into host cells or in their function as effectors of host cell invasion. Because IpaB shares significant sequence homology with the YopB translocator of Yersinia species, the ability for IpaC and SipC to associate with this protein was explored as a potential indicator of translocation function. Both proteins were found to bind to purified IpaB with an apparent dissociation constant in the nanomolar range, suggesting that they may differ with respect to effector function. Interestingly, whereas SB220 expressing sipC behaved like wild-type Salmonella, in that it remained within its membrane-bound vacuole following entry into host cells, SB220 expressing ipaC was found in the cytoplasm of host cells. This observation indicates that IpaC and SipC are responsible for a major difference in the invasion strategies of Shigella and Salmonella, that is, they escape into the host cell cytoplasm. The implications of the role of each protein's biochemistry relative to its in vivo function is discussed.

Organisational change: a methodology to uncover the business idea

A study was undertaken to identify the "Business Idea", as defined by van der Heijden (1996), in The Family Planning Association of WA Inc (FPWA) which is a Non-Government Organisation (NGO) in Perth, Western Australia. This organisation was chosen as, along with many other NGOs, it was undergoing major changes in its funding, role and required outcomes. A qualitative interpretivist single case study methodology employing grounded theory research principles and methods was used to study the Business Idea framework in this setting. Thirty-four members of FPWA's staff were interviewed and data was managed using NUD*IST4 and Decision Explorer data storage, data retrieval and graphical reproduction facilities. Results indicated that images of the Business Idea model within FPWA were largely consistent across all staff levels excepting members of the Board of Management. Changes within the organisation were impacting heavily on staff, who needed to be assisted over the transitional phase. Strong leadership and corporate direction were identified as essential if the FPWA was to balance the strongly held sense of social justice amongst its staff with a need for greater productivity efficiency and accountability across the organisation.

Observed incidence of tumorigenesis in long-term rodent studies of rAAV vectors

Gene therapy using recombinant adeno-associated virus vectors (rAAV) is generally considered safe. During the course of a study designed to determine the long-term efficacy of rAAV-mediated gene therapy initiated in newborn mice with the lysosomal storage disease, mucopolysaccharidosis type VII (MPSVII), a significant incidence of hepatocellular carcinomas and angiosarcomas was discovered. A hepatocellular carcinoma was first detected in a 35-week-old mouse and by 72 weeks of age, three out of five rAAV-treated MPSVII mice had similar lesions. These types of tumors had not been seen previously in long-term studies of MPSVII mice using recombinant enzyme or bone marrow transplantation. In an attempt to ascertain whether mouse strain or GUSB expression confers susceptibility to tumor formation, we histopathologically examined untreated normal mice of the same strain, untreated MPSVII mice, and normal mice overexpressing human GUSB for the presence of tumors and increased hepatocyte replication. The results of these studies do not indicate that MPSVII mice or mice overexpressing human GUSB are susceptible to tumor formation; however, the number of animals examined is too small to draw definitive conclusions. Results from quantitative PCR performed on the tumor samples suggest that the tumors are probably not caused by an insertional mutagenesis event followed by the clonal expansion of a transformed cell. In a separate study, a relatively large group of mice injected with varying doses and types of rAAV vectors had no evidence of hepatic or vascular tumors. Although the mechanism of tumor formation is currently unknown, the tumorigenic potential of rAAV vectors must be rigorously determined in long-term in vivo studies.

Murine mucopolysaccharidosis VIL: impact of therapies on the phenotype, clinical course, and pathology in a model of a lysosomal storage disease

The mucopolysaccharidoses are a group of lysosomal storage diseases caused by deficiency of an enzyme required for the normal degradation of glycosaminoglycans. Patients with mucopolysaccharidosis typically have widespread lysosomal storage, skeletal and central nervous system disease, and hepatosplenomegaly. Some patients with mucopolysaccharidosis may benefit from enzyme replacement therapy or bone marrow transplantation. Animal models of mucopolysaccharidosis have proven valuable for the evaluation of the effectiveness of potential treatments for patients with lysosomal storage disease. A murine model of MPS VII (Sly syndrome) has proven particularly useful because of its well-defined genetics and its well-characterized clinical, pathologic, and biochemical alterations, which resemble those seen in patients with mucopolysaccharidosis. Correction of these alterations forms the basis for evaluation of the effectiveness of novel treatments. A wide range of therapies have been tested using this model, including enzyme replacement therapy, bone marrow, stem cell, and neural progenitor cell transplantation, and a variety of viral-mediated gene therapies. The inferences drawn from these therapeutic studies using the murine MPS VII model are likely generalizable to other lysosomal storage diseases.

Corneodesmosin expression in psoriasis vulgaris differs from normal skin and other inflammatory skin disorders

SUMMARY

Corneodesmosin (Cdsn) is a late differentiation epidermal glycoprotein putatively involved in keratinocyte adhesion. The Cdsn gene lies within the susceptibility region on chromosome 6p21.3 (PSORS1) for psoriasis, a common chronic disfiguring skin disease. A particular allelic variant of Cdsn has a strong association with psoriasis. Therefore, genetically and biologically, Cdsn is a possible candidate gene for psoriasis susceptibility. To investigate a potential role for Cdsn in psoriasis pathogenesis, protein expression studies were performed by quantitative immunohistochemistry on normal skin, psoriatic skin (lesional and nonlesional), and other skin disorders using monoclonal antibodies (G36-19 and F28-27). In normal and nonlesional skin, Cdsn was expressed in stratum corneum and one or two layers of superficial stratum granulosum. In lesional psoriasis, there was a significant increase in Cdsn expression, which was observed in multiple layers of stratum spinosum and in stratum corneum. The expression pattern varied from granular, cytoplasmic immunoreactivity to cell surface labeling with weakly immunoreactive cytoplasm. In chronic atopic dermatitis, lichen planus, mycosis fungoides, and pityriasis rubra pilaris, Cdsn immunoreactivity was confined to stratum corneum and upper stratum granulosum with no stratum spinosum immunoreactivity. Immunoelectron microscopy of normal and lesional psoriatic skin demonstrated Cdsn release concomitant with involucrin incorporation into cell envelopes and completed before mature envelope formation. Extracellular release of Cdsn occurred at a lower level of the epidermis in psoriasis than normal skin. These protein expression studies provide evidence of altered Cdsn expression in psoriasis consistent with a role of Cdsn in disease pathogenesis. Further functional and genetic studies of Cdsn are justified to determine its role as a potential psoriasis-susceptibility factor.

Hematopoietic engraftment and survival in adult recipients of umbilical-cord blood from unrelated donors

BACKGROUND

Umbilical-cord blood from unrelated donors who are not HLA-identical with the recipients can restore hematopoiesis after myeloablative therapy in children. We studied the use of transplantation of umbilical-cord blood to restore hematopoiesis in adults.

METHODS

Sixty-eight adults with life-threatening hematologic disorders received intensive chemotherapy or total-body irradiation and then transplants of HLA-mismatched umbilical-cord blood. We evaluated the outcomes in terms of hematologic reconstitution, the occurrence of acute and chronic graft-versus-host disease (GVHD), relapses, and event-free survival.

RESULTS

Of the 68 patients, 48 (71 percent) received grafts of umbilical-cord blood that were mismatched for two or more HLA antigens. Of the 60 patients who survived 28 days or more after transplantation, 55 had neutrophil engraftment at a median of 27 days (range, 13 to 59). The estimated probability of neutrophil recovery in the 68 patients was 0.90 (95 percent confidence interval, 0.85 to 1.0). The presence of a relatively high number of nucleated cells in the umbilical-cord blood before it was frozen was associated with faster recovery of neutrophils. Severe acute GVHD (of grade III or IV) occurred in 11 of 55 patients who could be evaluated within the first 100 days after transplantation. Chronic GVHD developed in 12 of 33 patients who survived for more than 100 days after transplantation. The median follow-up for survivors was 22 months (range, 11 to 51). Of the 68 patients, 19 were alive and 18 of these (26 percent) were disease-free 40 months after transplantation. The presence of a high number of CD34+ cells in the graft was associated with improved event-free survival (P=0.05).

CONCLUSIONS

Umbilical-cord blood from unrelated donors can restore hematopoiesis in adults who receive myeloablative therapy and is associated with acceptable rates of severe acute and chronic GVHD.

Predictors of arteriovenous graft patency after radiologic intervention in hemodialysis patients

Arteriovenous grafts in hemodialysis patients are prone to recurrent stenosis and thrombosis, requiring frequent radiologic and surgical interventions to optimize their long-term patency. Little is known about the factors that determine graft outcome after a radiologic intervention. The present study examined the clinical and radiologic predictors of intervention-free graft survival after elective angioplasty or thrombectomy. A prospective computerized database was used to determine the outcomes subsequent to all graft angioplasties (n = 330) and thrombectomies (n = 326) performed at the University of Alabama at Birmingham between April 1, 1996, and June 30, 1999. Primary graft survival rates after angioplasty and thrombectomy were 86% versus 43% at 1 month, 71% versus 30% at 3 months, 51% versus 19% at 6 months, and 28% versus 8% at 12 months, respectively. The median intervention-free graft survival time was substantially longer after angioplasty than thrombectomy (6.7 versus 0.6 months; P < 0.001). The superior outcome of angioplasty over thrombectomy was observed even for the subset of procedures with no residual stenosis (median survival, 6.9 versus 2.5 months; P < 0.001). The median graft survival was inversely related to the magnitude of residual stenosis for both elective angioplasty and thrombectomy. Median intervention-free graft survival after angioplasty was inversely related to the postangioplasty intragraft to systemic systolic pressure ratio (7.6, 6.9, and 5.6 months for ratios <0.4, 0.4 to 0.6, and >0.6, respectively; P < 0.001). Intervention-free graft survival after angioplasty or thrombectomy was not affected by graft location (forearm versus upper arm), number of stenotic sites, or presence of diabetes. In conclusion, graft survival is substantially longer after elective angioplasty than thrombectomy, even when the radiologic appearance after the procedure suggests complete resolution of the stenotic lesion. Moreover, the risk for requiring a subsequent graft intervention can be predicted from two simple radiologic measurements: grade of stenosis and intragraft to systemic systolic blood pressure ratio. These parameters may help determine the frequency of monitoring for recurrent stenosis in a given graft.

A novel model of murine mucopolysaccharidosis type VII due to an intracisternal a particle element transposition into the beta-glucuronidase gene: clinical and pathologic findings

We describe the clinical and pathologic findings in a murine model of mucopolysaccharidosis VII (Sly disease) that arose spontaneously in the C3H/HeOuJ mouse strain. Affected gus(mps2J)/gus(mps2J) mice are deficient in beta-glucuronidase because of insertion of an intracisternal A particle element into intron 8 of the gus structural gene. This is the first model of a human lysosomal storage disease caused by an intracisternal A particle element insertion. Mice with the gus(mps2J)/gus(mps2J) genotype have < 1% of normal beta-glucuronidase activity and secondary elevations of other lysosomal enzymes. The phenotype includes shortened life-span, dysmorphic features, and skeletal dysplasia. Lysosomal storage of glycosaminoglycans is widespread and affects the brain, skeleton, eye, ear, heart valves, aorta, and the fixed tissue macrophage system. Thus the phenotypic and pathologic alterations in gus(mps2J)/gus(mps2J) mice are similar to those in patients with mucopolysaccharidosis VII. The finding of antibodies to beta-glucuronidase in some older gus(mps2J)/gus(mps2J) mice suggests the mice produce sufficient enzyme to elicit an immune response. The gus(mps2J)/gus(mps2J) model provides another well-defined genetic system for the study of the pathophysiology of mucopolysaccharidosis and for evaluation of experimental therapies for lysosomal storage diseases. The disease in gus(mps2J)/gus(mps2J) mice is less severe than that seen in the previously characterized B6.C-H2(bm1)/ByBir-gus(mps)/gus(mps) mouse model. Furthermore, unlike gus(mps)/gus(mps) mice, gus(mps2J)/gus(mps2J) mice are fertile and breed to produce litters, all of which are mucopolysaccharidosis VII pups. This feature makes them extremely useful for testing intrauterine therapies.

Semantic factors in the production of number agreement

This paper examines the role of semantic factors in the production of subject-verb number agreement. As an ostensibly grammatical process, number agreement provides an interesting case for examining the flow and interaction of semantic and syntactic information through the language-production system. Using a sentence-completion task, agreement errors can be elicited from subjects by presenting them with sentence fragments containing a complex noun-phrase, in which the nonhead noun is plural (e.g., The key to the cabinets ... WERE missing.). Previous research has demonstrated that the probability of making an error can be affected by varying the properties of the nouns in the complex noun phrase. By investigating which variables do and do not affect error rates, constraints on the flow of information through the production system can be inferred. In three experiments, we investigated the possible effects of three different semantic manipulations of the nouns in the complex NP: animacy, semantic overlap, and plausibility of modification by the sentence predicate. We found that both animacy and semantic relatedness had reliable effects on error rates, indicating that the mechanism involved in implementing agreement cannot be blind to semantic information. However, the plausibility with which each noun could serve as the subject of the sentence predicate had no effect on error rates. Taken together, these results suggest that while semantic information is visible to the agreement mechanism, there are still constraints on when this information can affect the process. Specifically, it may be the case that only information contained within the complex NP is considered for the purposes of implementing agreement.

A validation study comparing accelerator MS and liquid scintillation counting for analysis of 14C-labelled drugs in plasma, urine and faecal extracts

A comparison has been made between accelerator mass spectrometry (AMS) analysis and liquid scintillation counting (LSC) of plasma, urine and faecal samples containing 14C-labelled drugs. In an in vitro study in which human plasma was spiked (the term spiked is used in Section 2.6) with 14C-Fluconazole (14C-FL) over a concentration range of 0.1-2.5 dpm/ml, a correlation coefficient of 0.999 was determined for AMS analysis versus extrapolated LSC data. No significant day to day (or inter-day)variation was seen (P < 0.05 by ANOVA). Coefficients of variation for these analyses ranged from 2.68 to 6.50%. In vivo studies in which rats were given a high (11.5 microCi/kg) or low (18.1 nCi/kg) radioactive dose (to model an exposure of 0.9 microSievert to man) of 14C-Fluticasone propionate(14C-FP) showed that there was also a good correspondence between AMS and LSC data. A mass balance study in a single the faeces by 96 h; less than 1% of the administered dose was excreted in the urine. The limit of reliable measurement of drug related material, above background concentrations, by AMS analysis in this study was approximately 0.1 dpm/ml for plasma, 0.01 dpm/ml for urine without any sample extraction or concentration and 0.01 dpm/ml for faecal extracts. The data reported here demonstrate that AMS is an ultrasensitive and reliable method for analysing 14C-labelled drugs in human and animal body fluids.

Plants as biomarkers for monitoring heavy metal contaminants on landfill sites using sequential extraction and inductively coupled plasma atomic emission spectrophotometry (ICP-AES)

There have been a number of studies investigating metal uptake in plants on contaminated landfill sites, but little on their role as biomarkers to identify metal mobility for continuous monitoring purposes. Vegetation can be used as a biomonitor of site pollution, by identifying the mobilisation of heavy metals and by providing an understanding of their bioavailability. Plants selected were the common nettle (Uritica Dioica), bramble (Rubus Fruticosa) and sycamore (Acer Pseudoplatanus). A study of the soil fractionation was made to investigate the soil properties that are likely to influence metal mobility and a correlation exercise was undertaken to investigate if variations in concentration of metals in vegetation can reflect variations in concentration of the metals in soil. The soil was digested using aqua regia in a microwave closed vessel. The vegetation was digested using both microwave and a hydrogen peroxide-nitric acid mixture, refluxed on a heating block and a comparison made. The certified reference materials (CRMs) used were Standard Reference Material (SRM) 1547, peach leaves for vegetation (NIST) and for soil CRM 143R, sewage sludge-amended soil (BCR). The relative standard deviations (RSDs) were 2-6% for the analyses. Our findings show evidence of phytoextraction by some plants, (especially bramble and nettle), with certain plants, (sycamore) exhibiting signs of phytostabilisation. The evidence suggests that there is a degree of selectivity in metal uptake and partitioning within the plant compartments. It was also possible to correlate mobility phases of certain metals (Pb, Cu and Zn) using the soil and plant record. Zn and Cu exhibited the greatest potential to migrate from the roots to the leaves, with Pb found principally in the roots of ground vegetation. Our results suggest that analysis of bramble leaves, nettle leaves and roots can be used to monitor the mobility of Pb in the soil with nettle, bramble and sycamore leaves to monitor Cu and Zn.

Patient Care Bridge--mobile ICU for transit care of the critically ill

We describe the development and introduction of a Patient Care Bridge--a mobile ICU for the transit care of the critically ill. This stretcher-mounted Patient Care Bridge is being used for intensive transit care of the critically ill in Northland, New Zealand. It carries all the basic intensive care monitoring accoutrements, is lightweight and is suited for pre-hospital, inter-hospital and intra-hospital transit care. It is ideal for patient evacuation from the scene of motor vehicle and sporting accidents, surface transportation of patients by surface ambulance and aeroevacuation of patients by the Helicopter Emergency Medical Service. This economic and space efficient unit has been used for transfer of more than one thousand critically ill patients.

Ambulatory management of burns

Burns often happen unexpectedly and have the potential to cause death, lifelong disfigurement and dysfunction. A critical part of burn management is assessing the depth and extent of injury. Burns are now commonly classified as superficial, superficial partial thickness, deep partial thickness and full thickness. A systematic approach to burn care focuses on the six "Cs": clothing, cooling, cleaning, chemoprophylaxis, covering and comforting (i.e., pain relief). The American Burn Association has established criteria for determining which patients can be managed as outpatients and which require hospital admission or referral to a burn center. Follow-up care is important to assess patients for infection, healing and ability to provide proper wound care. Complications of burns include slow healing, scar formation and contracture. Early surgical referral can often help prevent or lessen scarring and contractures. Family physicians should be alert for psychologic problems related to long-term disability or disfigurement from burn injuries.

A novel in vitro model of early human adult B lymphopoiesis that allows proliferation of pro-B cells and differentiation to mature B lymphocytes

To develop a model of early human adult B lymphopoiesis, we cultured CD34+CD38+CD10+ pro-B cells in contact with AFT024 stroma in X-VIVO10 media with 5% serum. The cytokines FLT3L + SCF + IL7 + IGF1 were added at day 0, IL4 + IL5 + IL6 + IL10 and soluble CD40 ligand at day 14, and Staph. aureus Cowan particles on day 21. Greater than 25-fold expansion of CD34+CD38+CD10+ cells was seen at 2 weeks, the majority being CD34-CD19+ pre-B cells. Differentiation to immature IgM+ B cells was seen at 3 weeks and mature IgD+ B cells at 4 weeks, with secretion of IgM into the media. Immature and mature B cells could also be generated from culture of CD34+CD10+CD19- and CD34+CD10+CD19+ cells under similar conditions. In conclusion, we have demonstrated in vitro differentiation of early pro-B cells, and possibly common lymphoid progenitor cells, to mature B cells. Additional stimuli, provided by T helper cells or dendritic cells for example, may be required for the generation of IgG+ B cells or plasma cells. However, our culture system should be a valuable tool to further investigate B cell biology and B cell malignancies such as multiple myeloma and lymphoma.

Staphylococcal toxin-induced T cell proliferation in atopic eczema correlates with increased use of superantigen-reactive Vbeta-chains in cutaneous lymphocyte-associated antigen (CLA)-positive lymphocytes

Staphylococcal superantigens have been implicated in the pathogenesis of atopic dermatitis (AD). This may occur through superantigenic activation of T lymphocytes and their subsequent induction of the skin homing receptor CLA on activated cells. We investigated the proliferative responses of peripheral blood mononuclear cells (PBMC) from 10 patients with an infective exacerbation of AD and six normal controls to the staphylococcal superantigens, staphylococcal enterotoxin A and B (SEA, SEB) and toxic shock syndrome toxin-1 (TSST-1), and the mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A). We also assessed CLA and T cell receptor (TCR) Vbeta-chain expression by immunofluorescence and flow cytometry before and after stimulation. PBMC from AD patients showed two-fold increased proliferation to SEA and SEB (P < 0.01) compared with normals, whereas the response to mitogenic stimulation was identical. Analysis of (TCR) Vbeta-chain expression demonstrated increased use of superantigen-reactive Vbeta families in freshly isolated PBMC in AD patients compared with controls. This pattern of Vbeta-chain expression was only observed in the CLA+ but not the total population of T cells. Furthermore, there was a positive correlation between the enhanced PBMC proliferative response and increased expression of superantigen-reactive Vbeta families in atopic patients. These data support the concept that superantigens are important in the pathogenesis of this common condition, and also provide evidence that the increased use of certain Vbeta families in circulating, CLA+, skin homing lymphocytes is of functional significance.

Helicopter in transit care of the critically ill--the Whangarei experience

AIMS

To describe our experience in transit care of the critically ill in Northland and to highlight the multidisciplinary co-operation which renders this an efficient model of transit care in suburban and rural areas.

METHODS

Since its inception in 1988, Northland's wholly community owned rescue helicopter has played an integral part in transit Intensive Care in Northland. This aids in transportation of medical and nursing intensive care staff to outlying primary hospitals for patient stabilisation, subsequent transfer of the patient to the intensive care unit (ICU) in Whangarei and, occasionally, for transfer to specialised critical care services in Auckland.

RESULTS

As of August 1999, over 3,900 helicopter missions have been accomplished. A doctor, vetting each request for Medevac, minimises over-triage, thus ensuring adequate levels of transit care and effective utilisation of expensive resources. More than 90% of non-obstetric adult patients were ventilated and the number of Medevac missions increased over the years. The Accident Compensation Corporation (ACC) funds 40% of all flights, another 40% of flights are funded by Northland Health and the Order of St John funds the remainder.

CONCLUSIONS

With a widespread geography, efficient transit care of the critically ill is imperative to quality hospital care and ensures equity of access to the rural populace. The Whangarei system of transit intensive care is an ideal template for suburban and rural areas.

The effectiveness of one-to-one risk communication interventions in health care: a systematic review

OBJECTIVES

To assess whether risk-communication interventions are associated with changes in patient knowledge, attitudes, and behaviors, and to identify aspects of these interventions that modify these effects.

DESIGN

Systematic review.

DATA SOURCES

96 studies from the period 1985-1996 retrieved by electronic searching of eight databases, hand searching of four journals, contacting key authors, and reference list searching.

MAIN OUTCOME MEASURES

The effect size of the principal outcome was identified from each study. Outcomes measuring behavioral change were preferred; if these were not available, knowledge, anxiety, or risk perceptions were used, according to the focus of the study. Data were available to calculate the principal effect sizes for 82 of the studies.

ANALYSIS

Meta-regression.

RESULTS

The methodologic qualities of the studies varied. Nevertheless, risk-communication interventions generally had positive (beneficial) effects. Interventions addressing treatment choices were associated with larger effects than were those in other contexts, such as prevention or screening. Interventions using individual risk estimates were associated with larger effects than were those using more general risk information. Two design variables were identified as effect modifiers: randomized controlled trials were associated with smaller effects than other designs, and dichotomous outcomes were associated with larger effects than continuous outcomes.

CONCLUSIONS

Risk communication interventions may be most productive if they include individual risk estimates in the discussion between professional and patient. Patient decisions about treatment appear more amenable to change by these interventions than attendance for screening or modification of risky behavior.

Survival of Salmonella in bathrooms and toilets in domestic homes following salmonellosis

The survival and environmental spread of Salmonella bacteria from domestic toilets was examined in homes, where a family member had recently suffered an attack of salmonellosis. In four out of six households tested, Salmonella bacteria persisted in the biofilm material found under the recess of the toilet bowl rim which was difficult to remove with household toilet cleaners. In two homes Salmonella bacteria became incorporated into the scaly biofilm adhering to the toilet bowl surface below the water line. Salmonella enteritidis persisted in one toilet for 4 weeks after the diarrhoea had stopped, despite the use of cleaning fluids. Salmonellas were not isolated from normally dry areas such as, the toilet seat, the flush handle and door handle. Toilet seeding experiments were set up with Salmonella enteritidis PT4 to mimic environmental conditions associated with acute diarrhoea. Flushing the toilet resulted in contamination of the toilet seat and the toilet seat lid. In one out of three seedings, Salmonella bacteria were also isolated from an air sample taken immediately after flushing, indicating that airborne spread of the organism could contaminate surfaces in the bathroom. In the seeded toilet Salmonella bacteria were isolated from the biofilm in the toilet bowl below the waterline for up to 50 d after seeding, and also on one occasion from the bowl water. The results suggest that during diarrhoeal illness, there is considerable risk of spread of Salmonella infection to other family members via the environment, including contaminated hands and surfaces in the toilet area.

Attenuation of vasospasm and capillary no-reflow by ischemic preconditioning in skeletal muscle

Vasospasm and capillary no-reflow are common complications following replantation and free flap transfer. The purpose of the present study was to clarify whether vasospasm and capillary no-reflow which are induced by prolonged warm ischemia/reperfusion can be attenuated by ischemic preconditioning in the vascular isolated cremaster muscle model. Male Sprague-Dawley rats were anesthetized with pentobarbital. Arteriole diameter and capillary perfusion were measured utilizing intravital microscopy. In the control group, the cremasters sustained 4-hour warm global ischemia followed by 60-minute reperfusion. In the ischemic preconditioning group, the cremasters were subjected to one cycle of 45-minute ischemia followed by 15-minute reperfusion prior to 4-hour warm global ischemia followed by 60-minute reperfusion. The results from this experiment showed that ischemic preconditioning significantly attenuated ischemia/reperfusion-induced vasospasm and capillary no-reflow which occur early during reperfusion after prolonged warm ischemia in skeletal muscle. The mechanism of this phenomenon remains to be elucidated.