How reliable are test results from 17 laboratories on the basis of EN 1500 for a hand rub based on 80% (w/w)?

INTRODUCTION

A ring trial organized by the Association of Applied Hygiene (VAH) on the bactericidal efficacy of an ethanol-based hand rub was carried out in 17 laboratories according to EN 1500 with the aim of describing the variability of test results and fulfilment of the methodological acceptance criteria.

METHOD

As a test product, a hand rub based on 80% ethanol (w/w) was tested in comparison with the reference alcohol (60% iso-propanol, v/v) in a crossover design. After pre-washing and contamination following the norm, hands were treated either with the reference alcohol (2 × 3 mL for 2 × 30 s) or the test product (3 mL in 30 s). Post-decontamination values were determined immediately after the rub-in period. Validated neutralizers were used. The arithmetic means of all individual log10 pre-values, post-values and reduction values were calculated per laboratory. Non-inferiority was assumed when the Hodges-Lehmann 97.5% confidence limit was <0.6 in comparison with the reference. A z-score was calculated to determine the laboratory performance.

RESULTS

Two laboratories did not meet the acceptance criteria and were excluded from the analysis. The bactericidal efficacy of the test product was non-inferior to the reference product in four laboratories and not non-inferior in 11 laboratories. The z-score for the Hodges-Lehmann 97.5% confidence limit indicated a satisfactory performance in all laboratories.

CONCLUSION

We consider the EN 1500 test method to be robust in terms of the variability of test results. For products of borderline efficacy, the evaluation should be based on more than one test.

Interlaboratory reproducibility of a test method following 4-field test methodology to evaluate the susceptibility of Clostridium difficile spores

BACKGROUND

Sporicidal surface disinfection is recommended to control transmission of Clostridium difficile in healthcare facilities. EN 17126 provides a method to determine the sporicidal activity in suspension and has been approved as a European standard. In addition, a sporicidal surface test has been proposed.

AIM

To determine the interlaboratory reproducibility of a test method for evaluating the susceptibility of a C. difficile spore preparation to a biocidal formulation following the 4-field test (EN 16615 methodology).

METHODS

Nine laboratories participated. C. difficile NCTC 13366 spores were used. Glutaraldehyde (1% and 6%; 15 min) and peracetic acid (PAA; 0.01% and 0.04%; 15 min) were used to determine the spores' susceptibility in suspension in triplicate.

FINDINGS

One-percent glutaraldehyde revealed a mean decimal log₁₀ reduction of 1.03 with variable results in the nine laboratories (0.37-1.49) and a reproducibility of 0.38. The effect of 6% glutaraldehyde was stronger (mean: 2.05; range: 0.96-4.29; reproducibility: 0.86). PAA revealed similar results. An exemplary biocidal formulation based on 5% PAA was used at 0.5% (non-effective concentration) and 4% (effective concentration) to determine the sporicidal efficacy (4-field test) under clean conditions in triplicate with a contact time of 15 min. When used at 0.5% it demonstrated an overall log₁₀ reduction of 2.68 (range: 2.35-3.57) and at 4% of 4.61 (range: 3.82-5.71). The residual contamination on the three primarily uncontaminated test fields was <50 cfu/25 cm² in one out of nine laboratories (0.5%) and in seven out of nine laboratories (4%).

CONCLUSION

The interlaboratory reproducibility seems to be robust.

The gap between available knowledge and its use in clinical psychiatry

OBJECTIVE

The time span between knowledge becoming available and its integration into daily clinical routine is lengthy. This phenomenon is explored in this study.

METHOD

We used the outcomes of our activities for investigating and strengthening the research-based activities to improve physical health in the routines of clinical psychiatric wards as examples for our analyses.

RESULTS

The time span between new knowledge becoming available and its implementation into general clinical treatment is very long. However, a shortening of this time span is seen through active leadership backup and clinical research experience among psychiatrists and staff in the wards. In particular, the involvement of medical students interested in clinical research activities seems to have a positive impact.

CONCLUSION

Academia needs to be re-implemented into clinical psychiatry. Staff with research experience is needed in all professions to increase evidence-based practice. Leaders must take responsibility for implementing new knowledge into the routines of the department and must support staff in these activities on a daily basis.

First record of the deep-water whalefish Cetichthys indagator (Actinopterygii: Cetomimidae) in the North Atlantic Ocean

The whalefish Cetichthys indagator is reported for the first time in the North Atlantic Ocean. This record increases to five the number of specimens ever caught and represents the northernmost occurrence of this species in the northern hemisphere.

Effects of acute and chronic attenuation of postprandial hyperglycemia on postglucose-load endothelial function in insulin resistant individuals: is stimulation of first phase insulin secretion beneficial for the endothelial function?

The aim of the study is to determine if attenuation of postprandial hyperglycemia, by acutely and chronically enhancing postprandial insulin secretion in insulin-resistant individuals, improves the endothelial dysfunction. We assessed postoral glucose-load endothelial function in 56 insulin-resistant subjects with the Flow-Mediated-Dilation (FMD) technique. We randomized subjects to intervention/control group, and examined the acute and chronic effect of nateglinide, an oral antidiabetic drug of rapid action. In the intervention group, postoral glucose-load (post-OGL) FMD delta values deteriorated when compared to pre-OGL values, most significantly at 3 h post-OGL, on the following days: on the first study day termed "Baseline day" (p=0.04); on both days after 3 months of nateglinide treatment [with nateglinide administered on study-day "acute+chronic" (p=0.01); and without nateglinide on study-day "Closing day", p=0.001]. Post-OGL changes in the control group were nonsignificant both at Baseline and on Closing day. After a single dose of nateglinide "Acute day", post-OGL FMD deterioration was abolished. There was an increment in post-OGL FMD delta values most significant at 2 h post-OGL (p=0.02). Insulin concentrations increased while glucose concentrations decreased on study-days with nateglinide when compared to study-days without (p=<0.001 for both insulin and glucose). Comparisons for insulin and glucose concentrations between days with nateglinide, and likewise between days without, showed no significant difference. Postglucose load endothelial dysfunction can be prevented by administration of nateglinide, however, after 3 months of nateglinide treatment, this effect is abolished. Chronically increased insulin secretion could counteract the initial beneficial effect of reduced glucose excursions. We found no relationship between postprandial hyperglycemia and post-OGL FMD.

[MRSA hygiene in inpatient rehabilitation on the example of oncological rehabilitation--a position paper]

Infections and colonizations with methicillin resistant staphylococcus aureus (MRSA) are an increasing problem in German hospitals because they spread there more and more. In homes without predominant nursing care and without hospital-like medical care of the inhabitants, genotypically identical MRSA-strains are rarely found in room neighbours up to now. The recommendations on prevention and control of MRSA published by the Robert Koch-Institut (RKI) therefore are partially discrepant for these two fields. The setting in rehabilitation medical centres, from hygienic points of view, is in many respects similar to a medical practice or a home with predominantly independent inhabitants rather than to a hospital for patients with acute diseases. For an effective and humane stationary rehabilitation of patients with MRSA colonisation it would be desirable to define conditions under which the strict isolation-hygiene prescribed for acute hospitals could be deviated from, following e. g., the RKI recommendations for homes instead. With the input of a summary of the clinical relevance of MRSA and a comparison of both partly identical, partially however very different RKI-recommendations on prevention and control of MRSA the present article seeks to characterize the hygienic setting in (particularly oncological) stationary rehabilitation under the above aspects. A series of recommendations on MRSA hygiene in stationary rehabilitation follows, which depending on the risk profile involved is based partially on the RKI guidelines for hospitals, partially however, on the guidelines for homes. The recommendations have a preliminary character without claiming completeness or the rank of a guideline. They are intended to focus on a problem which arises more and more frequently also in rehabilitation centers. They can, in the individual case, provide a useful help for the practice in stationary rehabilitation particularly as there are no publications on the subject of MRSA hygiene so far which meet the circumstances in stationary rehabilitation in a different manner.

Pharmacological characterization of mouse GPRC6A, an L-alpha-amino-acid receptor modulated by divalent cations

BACKGROUND AND PURPOSE

GPRC6A is a novel member of family C of G protein-coupled receptors with so far unknown function. We have recently described both human and mouse GPRC6A as receptors for L-alpha-amino acids. To date, functional characterization of wild-type GPRC6A has been impaired by the lack of activity in quantitative functional assays. The aim of this study was thus to develop such an assay and extend the pharmacological characterization of GPRC6A.

EXPERIMENTAL APPROACH

We have engineered a novel cell-based inositol phosphate turnover assay for wild-type mouse GPRC6A based on transient co-expression with the promiscuous Galpha(qG66D) protein, known to increase receptor signalling sensitivity. This assay allowed for measurements of L-alpha-amino acid potencies. Furthermore, in combination with an assay measuring inward currents at Ca(2+)-activated chloride channels in Xenopus oocytes, the divalent cation-sensing ability of the receptor was examined.

KEY RESULTS

Using our novel assay, we demonstrate that the basic L-alpha-amino acids ornithine, lysine, and arginine are the most potent agonists at wild-type mouse GPRC6A. Using two different assay systems, we show that divalent cations do not activate the G(q) signalling pathway of mouse GPRC6A per se but positively modulate the amino-acid response.

CONCLUSIONS AND IMPLICATIONS

This is the first reported assay for a wild-type GPRC6A successfully applied for quantitative pharmacological characterization of amino acid and divalent cation responses at mouse GPRC6A. The assay enables further search for GPRC6A ligands such as allosteric modulators, which may provide essential information about the physiological function of GPRC6A.

Meeting the challenge of tobacco use within the Medicaid population

The Wisconsin Medicaid Program, which purchases health care for Wisconsin's low income residents, has entered into a number of partnerships designed to systematically address tobacco use by Medicaid recipients. With the help of Wisconsin HMOs, a chart audit established an overall tobacco use prevalence of 45.7%, about double that of the general population. A direct survey of Medicaid recipients confirmed a rate of 45.0%. The chart audit also revealed a dramatic under-utilization of currently available Medicaid smoking cessation benefits. Plans are now being made to increase this utilization on a statewide basis. In addition, a partnership with the Wisconsin Women's Health Foundation and the Bureau of Family and Community Health Program within the Division of Public Health has resulted in a pilot project to address tobacco use by low income, pregnant women. Finally, a partnership with a specialized HMO serving those with disabilities and the Mental Health Association in Milwaukee County plans to address tobacco use by those with chronic and persistent mental illness.

Haloperidol reinstates latent inhibition impaired by hippocampal lesions: data and theory

The effect of haloperidol administration on the impairment of latent inhibition produced by aspirative lesions of the hippocampus was examined in the rat eyeblink response preparation. During the preexposure phase, rats with hippocampal or control lesions were either exposed to a tone or allowed to sit in the training apparatus. During the conditioning phase, the tone was paired with an airpuff to the eye after the rats were injected with either saline or haloperidol. Although saline-injected rats with hippocampal lesions did not show latent inhibition, the phenomenon was reinstated in rats that received haloperidol injections. A possible locus of the interaction between hippocampal lesions and haloperidol is the nucleus accumbens. The reported data are well described by a neural network model of classical conditioning. This study contributes to the understanding of the neurophysiology of latent inhibition as well as the neuropsychological bases of schizophrenia.

Microbiological investigations to validate the preparation of corneal transplants

The globe and cornea are colonized by microorganisms and cannot be removed as sterile products. Antiseptic measures and storage of the cornea in medium containing antibiotics lead to an obvious reduction of the microbial flora. Unfortunately there is the possibility of secondary microbial contamination during the preparation. Large amounts of bacteria or resistant bacteria can ruin attempts to reduce the microbial flora. To validate the whole process of preparation we investigated the contamination of removed globes, environment, materials, instruments and media for each sequence of operation and eliminated sources of contamination. Recommendations are given to ensure a virtually sterile product at the end of preparation.

Haloperidol reinstates latent inhibition impaired by hippocampal lesions: data and theory

The effect of haloperidol administration on the impairment of latent inhibition produced by aspirative lesions of the hippocampus was examined in the rat eyeblink response preparation. During the preexposure phase, rats with hippocampal or control lesions were either exposed to a tone or allowed to sit in the training apparatus. During the conditioning phase, the tone was paired with an airpuff to the eye after the rats were injected with either saline or haloperidol. Although saline-injected rats with hippocampal lesions did not show latent inhibition, the phenomenon was reinstated in rats that received haloperidol injections. A possible locus of the interaction between hippocampal lesions and haloperidol is the nucleus accumbens. The reported data are well described by a neural network model of classical conditioning. This study contributes to the understanding of the neurophysiology of latent inhibition as well as the neuropsychological bases of schizophrenia.

Hygienic monitoring of environmental surroundings in office-based ambulatory surgery units--an instrument for infection control

Out-patient operations cause lower costs and they are a method the patients are less burdened with than it is the case with usual operating methods. Avoiding nosocomial infections is regarded as another advantage. The rate of infection can be given by a carefully kept nosocomial infection surveillance. Ambulatory surgery units have difficulties in keeping these statistics because they often do not take over the after-treatment of this patients. Out-patient operations in surgeries must guarantee the same standard of hygiene which can usually be found in hospitals. Hospital epidemiologists, health authorities and professional associations have published corresponding guidelines with organizational/functional and structural requirements. These requirements, however, are only met by few ambulatory practices. Surgery holders justify the non-observance of the guidelines by supposing that the spectrum of germs in their office differs from that in a hospital and that there aren't any pathogens. The standard of hygiene in ambulatory surgery units is not controlled regularly. Therefore the hygienic conditions and the microbial burden of five surgeries that carry out out-patient operations under general anaesthesia were determined within the scope of microbial monitoring of the surroundings. Only two surgeries achieved a standard of hygiene which is comparable with that of a hospital. Up to 42% of the taken samples were sterile. The other three surgeries did not meet the requirements. The microbial burden in these surgeries was distinctly higher. The spectrum of detected microorganisms was very wide and there were pathogens too. Hygienic controls and monitoring of the surroundings should be carried out regularly as a measure to guarantee the production and maintenance of quality. Thus the actually achieved hygienic standard in the surgeries can be controlled and improved if necessary. Ambulatory surgeries should be liable to similar hygienic controls as hospitals.

Neuropsychological functioning and MRI signal hyperintensities in geriatric depression

OBJECTIVE

The purpose of this study was to examine the relationship between signal hyperintensities--a probable marker of underlying pathology--on T2-weighted magnetic resonance brain scans and neuropsychological test findings in elderly depressed and normal subjects.

METHOD

Elderly subjects with a DSM-III-R diagnosis of major depression (N=41) and normal elderly comparison subjects (N=38) participated in a magnetic resonance imaging study (1.0-T) of signal hyperintensities in periventricular, deep white matter, and subcortical gray matter. Hard copies of scans were rated in random order by research psychiatrists blind to diagnosis; the modified Fazekas hyperintensity rating scale was used. Cognitive performance was independently assessed with a comprehensive neuropsychological battery. Clinical and demographic differences between groups were assessed by t tests and chi-square analysis. Relationships between neuropsychological performance and diagnosis and hyperintensities and their interaction were analyzed by using analysis of covariance, with adjustment for age and education.

RESULTS

Elderly depressed subjects manifested poorer cognitive performance on several tests than normal comparison subjects. A significant interaction between hyperintensity location/severity and presence/absence of depression on cognitive performance was found: depressed patients with moderate-to-severe deep white matter hyperintensities demonstrated worse performance on general and delayed recall memory indices, executive functioning and language testing than depressed patients without such lesions and normal elderly subjects with or without deep white matter changes.

CONCLUSIONS

Findings validate cognitive performance decrements in geriatric depression and suggest possible neuroanatomic vulnerabilities to developing particular neuropsychological dysfunction in depressed subjects.

Construction of specific erythromycin resistance mutations in the temperate lactococcal bacteriophage TP901-1 and their use in studies of phage biology

A method for the construction and isolation of specifically designed mutations of the temperate lactococcal phage TP901-1 has been developed. Two different erm-labeled mutants were isolated. One was shown to be defective in lysogenization and excision. The other, showing normal lysogenization, was used for host range studies.

Down-regulation of tissue specific tumor necrosis factor-alpha in the liver and lung after burn injury and endotoxemia

Burn injury and endotoxin lead to the development of a systemic inflammatory response. Because tumor necrosis factor-alpha (TNF-alpha) is a component of the proinflammatory response, we have determined the effect of burn injury and endotoxin in a murine model of thermal on tissue specific TNF-alpha levels in the liver and lung. Male mice were divided into four groups and injected with endotoxin (ETX) (2.5 mg/kg intraperitoneally) or saline (CNTL) or subjected to a 16% full-thickness scald burn (B), or ETX administration 72 hours after burn injury (B+ETX). Animals were killed at 0 to 24 hours after ETX or CNTL, 0 to 72 hours after B, and 72 to 96 hours after B+ETX (ETX administration 72 hours after B). TNF-alpha mRNA by Northern blot and protein analysis by enzyme-linked immunosorbent assay were determined and protein expressed as nanogram per gram of tissue. Statistical analysis was performed using analysis of variance with significance at p < 0.05. Burn injury did not result in detectable levels of liver or lung TNF protein or mRNA. Endotoxin administration resulted in a near six-fold rise in liver TNF protein compared with controls at 1, 2, and 6 hours after ETX (p < 0.05 to p < 0.001). Liver mRNA remained elevated from 20 minutes to 24 hours after ETX versus CNTL (p < 0.05). Endotoxin injection produced a persistent lung TNF protein elevation reaching significance at 1 and 2 hours (p < 0.001) and a rise in mRNA at 40 minutes to 6 hours (p < 0.05) versus CNTL. The liver showed a trend of reduced mRNA after B+ETX versus ETX (p = NS), whereas protein levels were reduced by 50 to 60% at 1 and 2 hours (p < 0.01). Lung mRNA values after B+ETX were only 40% compared with ETX at nearly all time points (p < 0.001) but were 15 times above CNTL values at 2 hours (p < 0.05). Based on these results, we conclude that burn injury did not cause an increase in liver or lung tissue specific TNF-alpha. However, the presence of a preexisting burn injury dramatically altered the response to endotoxin and the primary point of regulation appears to be at the posttranscriptional level.

Comparative studies on the interaction of proteins with a polydimethylsiloxane elastomer. I. Monolayer protein capture capacity (PCC) as a function of protein pl, buffer pH and buffer ionic strength

Polydimethylsiloxane (PEP) is widely used in medical prostheses and therefore is in contact with plasma and secretory proteins. Two pair of globular proteins, lactoferrin (Lf) and transferrin (Trf), and bovine IgG1 and IgG2a, which differ substantially between pair members in their pl, were used to study the interaction of a PEP widely used in breast implants and soluble protein. Studies were done using iodinated proteins over a concentration range that resulted in an apparent protein monolayer. Secondary incubations with dilute protein solutions were needed to form the monolayer on PEP, possibly as a consequence of micro air bubbles trapped on its highly textured surface as shown by atomic force microscopy. Immunoassay quality polystyrene microtiter wells were used as controls. Adsorption studies were routinely performed at pH 4, 7 and 10 and at ionic strengths corresponding to 0.95, 9.5 and 90.0 mS. The protein capture capacity (PCC) of PEP for Lf and Trf was optimal at physiological pH and ionic strength and comparable under these conditions to that of Immulon 2 (Imm 2) microtiter wells. While increasing the ionic strength and pH further increases the PCC of Imm 2 for Lf and Trf, this markedly lowered the PCC of PEP for these proteins suggesting that initial polar interactions may precede subsequent hydrophobic bonding to PEP. This was tested using a hydrophilic variant of PEP, which when tested in a 90.0 mS buffer, showed a > five-fold lower PCC at neutral and alkaline pH. The greatly reduced PCC of the hydrophilic variant might also suggest that hydrophilic variants of silicone would be more biocompatible than those currently used. The PCC of PEP for the IgGs was less than that of Imm 2 but still optimal at physiological conditions. Consistent with the data on Lf/Trf, PCC progressively decreased with increasing ionic strength at alkaline pH. Differences in pl between the protein pairs had only a marginal effect on the PCC of PEP. Monolayer adsorption on both PEP and Imm 2 was slowly reversible and greater in the presence of free ligand (< 2% in 16 h) suggesting that the process follows Mass Law principles. However, even in the presence of non-ionic detergent and free ligand, 85-90% remained bound on either surface. Thus, desorption of proteins in the monolayer should not complicate subsequent immunochemical studies conducted on adsorbed monolayers.

A resolvase-like protein is required for the site-specific integration of the temperate lactococcal bacteriophage TP901-1

The integration system of the temperate lactococcal phage TP901-1 was characterized in Lactococcus lactis subsp. cremoris LM0230 and MG1363 with the use of deletion derivatives of the integration vector pBC143 (B. Christiansen, M. G. Johnsen, E. Stenby, F. K. Vogensen, and K. Hammer, J. Bacteriol. 176:1069-1076, 1994). The phage-encoded elements necessary for integration were localized on a 2.8-kb NsiI-EcoRI fragment including the phage attachment site, attP. This fragment was DNA sequenced, and sequence analysis revealed three putatively expressed open reading frames, Orf1, Orf2, and Orf3 By the introduction of mutations within the orf1, orf2, and orf3 genes, it was shown that only Orf1 was necessary for the integration process. Furthermore, it was found that Orf1, attP, and a 425-bp region upstream of the orf1 gene are sufficient for integration. Orf1 contains 485 amino acids and is located just upstream of attP. The N-terminal 150 to 180 amino acids of Orf1 showed 38 to 44% similarity to the resolvase group of site-specific integrases, while no similarity to known proteins was found in the C-terminal end. Bacteriophage TP901-1 therefore contains a unique integration system that does not resemble the Int class of site-specific integrases usually found in temperate bacteriophages. The constructed integration vector, pBC170, integrates into the chromosomal attachment site very efficiently and forms stable transformants with a frequency corresponding to 20% of the transformation efficiency.

[Can contact nurses point the way to competence in practice? Nurses as practice mentors in nursing education]

The contact nurse is a central person as a carrier of knowledge and experience in nursing practice, which is important that the student nurse has access to. In order to gain insight into the passage of knowledge between 3 contact nurses and their students, I have carried out a qualitative investigation.

METHOD

The method chosen is that of participation, open observation and semi-structured interviews.

FINDINGS

While guiding the student, the contact nurse made explicit her way of judging specific nursing situations. She appealed to the use of perceptive insight, and made explicit the complexity in an "everyday situation" in nursing practice. Counselling in patient-situations thus reflects the value of the traditional master-apprentice roles. Professional argumentation delving deeper than more down-to-earth judgements, appears to be absent from the investigation. This shows the importance of a greater degree of reflection in the contact nurse's role as a counsellor.

Characterization of the lactococcal temperate phage TP901-1 and its site-specific integration

The temperate lactococcal phage TP901-1, induced by UV light from Lactococcus lactis subsp. cremoris 901-1, was characterized. The restriction map was found to be circular, and the packaging of TP901-1 DNA was concluded to occur by a headful mechanism. The pac region was localized on the 38.4-kb phage genome. TP901-1 belongs to the class of P335 phages (V. Braun, S. Hertwig, H. Neve, A. Geis, and M. Teuber, J. Gen. Microbiol. 135:2551-2560, 1989). Evidence is presented that the phages TP936-1 (V. Braun, S. Hertwig, H. Neve, A. Geis, and M. Teuber, J. Gen. Microbiol. 135:2551-2560, 1989) and C3-T1 (A. W. Jarvis, V. R. Parker, and M. B. Bianchin, Can. J. Microbiol. 38:398-404, 1992) are very closely related to or are identical to TP901-1. The lytically propagated TP901-1 phages were able to lysogenize both indicator strains Lactococcus cremoris 3107 and Wg2. Lysogenization resulted in site-specific integration of the phage genome into the bacterial chromosome. Only one chromosomal attB site was found in 20 independent lysogens. The attP region of TP901-1 and the attL and attR regions were cloned and sequenced. The results showed a core region of only 5 bp, in which the recombination occurs, followed after a 1-bp mismatch by a 7-bp identical region, TCAAT(T/C)AAGGTAA. This result was further verified by sequencing of the attB region obtained by PCR. An integration vector was constructed with the 6.5-kb EcoRI fragment from TP901-1 containing attP. This vector also functions in the plasmid-free strains, MG1363 and LM0230 with only one specific attB site, strongly indicating a more general use of the TP901-1-based integration vector in lactococci.

The efficacy of low temperature plasma (LTP) sterilization, a new sterilization technique

The efficacy of low temperature plasma (LTP) sterilization, a newly developed sterilization procedure was tested. Following experiments were carried out: Determination of the most resistant test organism, influence of 10% and 20% defibrinated sheep blood or varying salt concentrations on the efficacy of the sterilization process, influence of the carrier position in the sterilization chamber and in the sterilization pouches, influence of a loaded sterilization chamber, comparative efficacy of EO and LTP, steel carriers with a blood burden of 0%, 5% and 10%, comparative efficacy of EO and LTP, strip carriers in endoscopes, blood burden 0% and 10%, with and without adaptors, evaluation of two bioindicator models. B. pumilus was the test spore that overall seemed to be most resistant to the sterilization procedure. Supplementation of the test suspension with blood or saline crystals resulted in significantly reduced efficacy and has to be avoided in practical operation. The fully loaded sterilization chamber or the position of germ carriers on the shelves had no negative influence on the effectivity of the sterilization process. There were no significant differences between EO and LTP, the blood burden not exceeding 5%. 10% blood burden resulted in a significantly weaker action of LTP. For sterilization of long lumens adaptors containing hydrogen peroxide are necessary. An appropriate bioindicator tube model is introduced.

[The danger of infection in inhalation rooms]

There are alarming reports about high counts of Legionella and Pseudomonas in the aerosol of inhalation-rooms. We therefore investigated 14 institutions (6 kurhauses, 5 hospitals and 3 sanatoria for children) in Schleswig-Holstein, each of them at least five-fold. For that purpose the inhalant (seawater as a rule) was investigated for the total bacterial number and the number of Legionella. Cfu/m3 air were determined at the aerosol outlet and a qualitative search for Legionella was done in the piping. In addition bacterial numbers in the air at the breathing-levels of patients were measured in order to be able to assess health hazards by germs of other patients. Detected bacterial numbers (10(1) - > 10(4)) were basically subject to the handling of the equipment and the type of apparatus used. Predominantly Staphylococci and Bacilli were found and above all when the first row of investigations was carried out large numbers of Pseudomonas, Aeromonas and others occurred. Legionella could not be detected. As a whole the investigations showed that properly maintained room-inhalators pose no higher risk of infection. These facilities, however, might be contaminated at any time and there is a certain--even though comparatively low--risk of infection due to germs exhaled by other patients. Patients, which are predisposed to infections of the respiratory tract--f.i. patients suffering from mucoviscidosis or patients with lowered resistance--should therefore generally use single inhalators.

[The suitability of commercial bioindicators with spores of B. stearothermophilus for the testing of formaldehyde gas sterilizers]

Commercially available biological indicators with spores of B. stearothermophilus were investigated by the Hygiene-Institutes of Kiel and Lubeck. The objective was to find out if those indicators to which sheep blood was added subsequently correspond to the formaldehyde resistance required by. DIN 58948, part 14 (DIN 58948, part 13). Both working groups determined unanimously that the indicators of one producer showed a resistance too low compared to the remaining biological indicators showing a much higher resistance than required. Even biological indicators manufactured strictly in accordance to the testing standard were more resistant than demanded. This also corresponded to the commercially available untreated spores. On the other hand, practice showed that the biological indicators investigated within this study can be easily killed by formaldehyde sterilizers if they respond to the technical standard. In order to realize the testing of these sterilizers with indicators of a generally accepted resistance we propose either to demand for an equivalently higher formaldehyde resistance or to set up a killing period for the spore resistance from 150 to 240 min until experimentally important data are available. Concerning the blood containing indicators the results of both working groups differed considerably within the limits of formaldehyde efficiency whereas this was not the case with untested commercially available spores. As the addition of thinned blood did not cause an increase in resistance we recommend, in the interest of standardized investigative conditions, not to use it.

Global increase in response latencies by early middle age: complexity effects in individual performances

Ten young women (age 20 to 22 years) and 10 middle-aged women (age 36 to 44 years) served as subjects in choice reaction time, letter classification, and abstract matching-to-sample tasks. In each of seven conditions, the older group responded more slowly than the younger group. Age differences showed a complexity effect. That is, differences between the latencies of young and old subjects increased as the latency of the young subjects increased. Both linear and power functions accurately described the relation between the latencies of the middle-aged and young adult groups. This was true not only for the relation between average latencies but also for the relation between corresponding quartiles of latency distributions. Similar results were observed at the individual level: All middle-aged subjects showed complexity effects, and, for each middle-aged subject, the relation between her latencies and those of the average young adult was well described by linear and power functions. These findings indicate that age-related slowing is apparent by age 40, and that complexity effects are observable in individual performances. This slowing is global and not specific to particular tasks, as indicated by the fact that the latencies of older adults can be predicted directly from those of younger adults without regard to the nature of the task.

The role of psychopathology and gender in respiratory self-regulation

A group of 12 male and 12 female psychiatric patients were recruited among an anxiety-disordered population, and their performance on a respiratory modulation test was compared with that of a matched non-patient sample. Inferior performance was expected in the patient group, and males were expected to show better respiratory modulation than females. Results supported the conclusion that females were less able than males in modulating respiratory muscle behaviour according to requested patterns, and female psychiatric patients showed a relative lack of flexibility in the thorax or abdomen regions or in both trunk levels.

Behavioral medicine programs in teaching hospitals

Behavioral medicine is a relatively new interdisciplinary field which combines biomedical and behavioral science knowledge, and applies them to prevention, diagnosis, treatment and rehabilitation. Behavioral medicine programs provide a valuable service to patients with chronic illness, psychosomatic or functional disorders, treatment noncompliance, and behavioral risk factors. Behavioral medicine faculty are also active in teaching and research on patient behavior, interviewing skills, health promotion and counseling, and management of chronic illnesses. However, the survival of behavioral medicine programs in teaching hospitals depends on their economic viability and academic status. Positive action is needed to ensure their continued growth and development.