In utero and lactational treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin impairs mammary gland differentiation but does not block the response to exogenous estrogen in the postpubertal female rat

These experiments tested whether in utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alters mammary gland differentiation, estrogen receptor alpha (ERalpha) expression levels, or the response to estrogen in the female postpubertal rat mammary gland. Pregnant Holtzman rats were administered a single oral dose of 1 microg/kg TCDD or vehicle on gestation-day 15. Exposed and non-exposed female offspring were weaned on postnatal day 21 and ovariectomized at 9 weeks of age. Two weeks later, both TCDD and control animals were divided into 3 groups, receiving treatment with placebo, 0.025, or 0.1 mg 17beta-estradiol pellet implants. After 48 h, mammary tissue was removed for analysis following euthanasia. TCDD-exposed mammary glands demonstrated impaired differentiation as measured by the distribution of terminal ductal structures and increased expression levels of ERalpha. The response to exogenous estrogen was tested in TCDD-exposed animals and compared to control non-exposed animals. Estrogen stimulation of the TCDD-exposed glands induced progesterone receptor expression and mammary gland differentiation as measured by a shift in distribution from terminal end buds and terminal ducts to Types I and II lobules. Control glands were better differentiated at baseline and did not exhibit any significant changes in the distribution of terminal ductal structures following estrogen stimulation. The increase in progesterone receptor-expression levels by exogenous estrogen in control glands was similar to the TCDD-exposed glands. These experiments demonstrate that in utero and lactational exposures to TCDD impair mammary gland differentiation but that TCDD-exposed mammary glands retain the ability to differentiate in response to estrogen.

Sonographic features of dialysis-related amyloidosis of the shoulder

This study evaluated the diagnostic role of ultrasonography in dialysis-related amyloidosis in shoulders of chronically hemodialyzed patients. Fourteen shoulders of 12 long-term hemodialysis patients were examined. All patients had been on dialysis for at least 10 years. All patients had varying degrees of pain and limitations of movement in the studied shoulders. Dialysis-related amyloidosis was the presumed diagnosis in all patients. Any patient with a history of any disease, other than dialysis-related amyloidosis, capable of producing a pathologic shoulder condition was excluded. The following parameters were studied: supraspinatus and biceps tendon thickness, tendon tears, synovial thickening, and the presence of hypoechoic material around tendons and within bursae. All shoulders had a nonhomogeneous thickening, greater than 7 mm, of the supraspinatus tendon. Seven shoulders (50%) had abnormal thickening of the biceps tendon (4 mm or greater), and two shoulders had abnormal thickening of the subscapularis tendon. Hypoechoic deposits were seen in the subdeltoid bursae and biceps sheaths in five and six shoulders, respectively. Three shoulders showed partial tears of the supraspinatus tendon, one shoulder showed a tear in the biceps tendon, and one shoulder had a tear in the subscapularis tendon. Ultrasonography is an excellent imaging modality in diagnosing the presence of dialysis-related amyloidosis in symptomatic shoulders of long-term hemodialysis patients, without having to resort to invasive procedures. The results of previous studies have been confirmed and new ultrasonographic findings described. Of particular interest is the involvement of the subscapularis tendon in dialysis-related amyloidosis. Repeat ultrasonography can become an important way to follow-up progression of shoulder dialysis-related amyloidosis in hemodialyzed patients.

Graded expression of ceh-14 reporters in the hypodermis is induced by a gonadal signal

ceh-14, a LIM class homeobox gene from Caenorhabditis elegans, is the orthologue of the vertebrate Lhx3/Lhx4 genes. ceh-14 reporter constructs are expressed in several different cell types: head and tail neurons, spermatheca and hypodermis. An intriguing aspect of the hypodermal expression pattern is that it takes the form of a gradient which is strongest in the central body region in L4 to young adult hermaphrodites. Promoter deletion analyses revealed that important regulatory elements for hypodermal expression are located within the transcribed region of ceh-14. Since a large part of the hypodermis is a syncytium, we hypothesized that this expression is triggered in a non-cell-autonomous fashion, a possible source being the underlying gonad. In males, which have a different gonadal organisation, the ceh-14 reporter constructs are expressed in a gradient that is strongest in the tail. By laser ablation of the gonadal precursor cells we found that ceh-14 reporter construct expression is eliminated in the hermaphrodite hypodermis, suggesting that the gonad plays a role in the generation of the gradient. Several signaling pathways are known in the gonad and the vulva, thus we crossed the mutations lin-3, egl-17 and lin-12 with the ceh-14 reporter lines. However, the expression of the reporter constructs is not affected in these mutant backgrounds. This suggests that another, presently unknown, signal triggers the graded hypodermal expression.

Nurse-patient sexual contact in psychiatric hospitals

Sexual contacts between nurses and patients in psychiatric hospitals have not been investigated systematically. The aim of the present study was to determine the frequency of nurse-patient sexual relationships and their prominent characteristics on the one hand and the nurses' attitudes towards these contacts on the other. A questionnaire was mailed to 714 nurses employed at two psychiatric hospitals. Although 94% of the 279 respondents considered sexual contact (defined as "physical contact between a patient and a nurse, in which sexual arousal occurred in the nurse") to be inappropriate, 17% of the male and 11% of the female responding nurses reported having had such contacts with patients.

UV inactivation, liquid-holding recovery, and photoreactivation of Escherichia coli O157 and other pathogenic Escherichia coli strains in water

Drinking water, water used in food production and for irrigation, water for fish farming, waste water, surface water, and recreational water have been recently recognized as a vector for the transmission of pathogenic Escherichia coli, especially serotype O157:H7. We investigated the UV (253.7 nm) inactivation behavior and the capability of dark repair (liquid-holding recovery) and photoreactivation of seven pathogenic (including three enterohemorrhagic E. coli) strains and one nonpathogenic strain of E. coli (ATCC 11229) with respect to the use of UV light for water disinfection purposes. Because most bacteria and yeast are known to be able to repair UV damage in their nucleic acids, repair mechanisms have to be considered to ensure safe water disinfection. We found a wide divergence in the UV susceptibility within the strains tested. A 6-log reduction of bacteria that fulfills the requirement for safe water disinfection was reached for the very most susceptible strain O157:H7 (CCUG 29199) at a UV fluence of 12 J/m2, whereas for the most resistant strain, O25:K98:NM, a UV fluence of about 125 J/m2 was needed. Except for one strain (O50:H7) liquid-holding recovery did not play an important role in recovery after UV irradiation. By contrast, all strains, particularly strains O25:K98:NM, O78:K80:H12, and O157:H7 (CCUG 29193), demonstrated photorepair ability. For a 6-log reduction of these strains, a UV fluence (253.7 nm) up to 300 J/m2 is required. The results reveal that the minimum fluence of 400 J/m2 demanded in the Austrian standard for water disinfection is sufficient to inactivate pathogenic E. coli. A fluence of 160 J/m2 (recommendation in Norway) or 250 J/m2 (recommendation in Switzerland) cannot be regarded as safe in that respect.

Unusual association: Streptococcus bovis tricuspid endocarditis with atrial-septal aneurysm and patent foramen ovale

Streptococcus bovis endocarditis is a frequent cause of streptococcal endocarditis and is associated with colonic tumours. The tricuspid valve is very rarely affected and its involvement is a complication which can lead to a less favourable outcome. We report the seventh case of tricuspid valve endocarditis due to S. bovis, and the first, to our knowledge, to be associated with an atrial-septal aneurysm and a patent foramen ovale. The underlying medical conditions and predisposing factors for development of tricuspid valve endocarditis are described and interesting new echocardiographic data are presented. The current guidelines on antibiotic therapy for S. bovis tricuspid valve endocarditis are reviewed.

Perceived psychopathology in a painter's work

R. A. Blakelock was a highly acclaimed 19th Century visionary American painter who spent 25 years in mental hospitals. Students rated random samples of Blakelock's work completed before, during, and after his breakdown. Paintings completed after the start of his long-term hospitalization were rated lower in skill and higher in psychopathology than those done before his breakdown. The difference in perceived psychopathology persists when ratings for skill level are controlled. There were also differences due to training level of raters and whether or not the paintings were presented in color.

Measurement of UV radiation using suspensions of microorganisms

The measurement of solar UV radiation is usually performed using physical devices like photodiodes or photomultipliers or with chemical substances (actinometry). The application of biological material such as microorganisms for this purpose has gained increasing importance in the last few years. The microorganisms may be dried and spread on a flat surface or they may be in aqueous suspensions contained in UV-transparent vessels. If the measurements are done on flat surfaces, the irradiance weighted by the action spectrum of the dried microorganism used is the result of the measurement. If aqueous suspensions of microorganisms are used, contained for instance in spherical vessels, the fluence weighted by the action spectrum of the microorganisms in the aqueous suspension is the result. A problem of this method of measurement can be that inside the vessel the distribution of UV radiation is usually not homogeneous, causing distributions of fluences among the irradiated microorganisms, which may result in variation of the results depending on the mixing characteristics of the suspension during irradiation.

Group A beta-hemolytic streptococcus meningitis: clinical and microbiological features of nine cases

Group A beta-hemolytic streptococcus (GAS) meningitis is a rare disease in adults. We conducted a retrospective study to describe clinical and microbiological features of nine cases of GAS meningitis in Switzerland. Of nine patients, six had neurosurgical conditions, and five had upper respiratory tract infections. Eight cases were community-acquired. The outcome of GAS meningitis was favorable; only one patient died of neurosurgical complications. No patient presented with toxic shock syndrome. Serotyping failed to reveal a dominant strain, and genotyping revealed that two strains carried the gene encoding the streptococcal pyrogenic exotoxin C and that one strain carried the gene encoding the streptococcal pyrogenic exotoxin A. Our observations suggest that GAS meningitis in adults is associated with neurosurgical conditions and/or an upper respiratory tract infection.

Quality of water used for haemodialysis: bacteriological and chemical parameters

BACKGROUND

The bacterial and chemical contamination of dialysate fluids are important problems in haemodialysis therapy and may be caused by the water used for dialysate preparation.

METHODS

We performed a survey of the microbiological and chemical quality of the water used in seven dialysis wards. Special attention was paid to the effects of each water treatment step, for example ion exchange, reverse osmosis and UV disinfection, on the number of bacteria (measured as colony forming units, CFU), the amount of endotoxin (endotoxin units, EU) and various chemical parameters, the main focus being on calcium, magnesium, sulphate, aluminium and heavy metals.

RESULTS

CFU values exceeding the European Pharmacopeia value, determined at an incubation temperature of 22 degrees C, were found in the samples of raw water (20.0%, n=25), after ion exchange (66.7%, n=12), after reverse osmosis (33.3%, n=18) and also in samples of the dialysis water taken at the inlets (12.5%, n=40) and outlets (50.0%, n=18) of the machines. Whereas all raw water samples from the wards showed high mean values for endotoxin (0.56-9.10 EU/ml) and the endotoxin levels were often enhanced after ion exchange (0.13- >9.49 EU/ml), treatment by reverse osmosis led to a satisfactory decrease in endotoxin in all samples (<0.03 EU/ml). Sufficient reductions in calcium, magnesium and sulphate could only be achieved by the combined application of ion exchange and reverse osmosis. Mercury contamination was observed in the samples after ion exchange at three treatment plants, this was possibly caused by polluted regenerants. Increased amounts of aluminium, copper and zinc were found in water samples from different sites in the treatment systems and were caused by materials in contact with the water.

CONCLUSIONS

A sufficient chemical water purification treatment system should consist of ion exchange and reverse osmosis. Attention has to be paid to the suitability of materials in contact with the water and of the chemicals used, for example regenerants or corrosion inhibitors. From the microbiological point of view, a safety UV disinfection step in the water-treatment system is favourable. To avoid bacterial recontamination periodic cleaning and disinfecting of the water-treatment and distribution systems, as well as the dialysis machine are essential. There is the need for complete guidelines regarding dialysis water that include all relevant chemical and microbiological parameters. Based on this standard, periodic examination of the water after each treatment step has to be performed.

Interactions of "Limax amoebae" and gram-negative bacteria: experimental studies and review of current problems

Free-living amoebae can harbour bacteria inside their cysts giving them a microhabitat and protecting them from disinfectants. The aim of this study was to evaluate the potential importance of "Limax amoebae" as vectors for environmental and nosocomial bacteria in a hospital. It was shown that free-living amoebae are ubiquitous in the investigated hospital, occur syntopically with facultative human pathogens (Comamonas acidovorans and Pseudomonas aeruginosa) and may serve as hosts not only for these but also for bacteria isolated from clinical specimens (Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa); temperature is apparently of crucial importance for the interactions between these microorganisms. Recent studies have shown that "Limax amoebae" apart from acting as protective hosts, may also play a role for the thermotolerance, invasiveness and antibiotic-resistance of bacteria. Considering also the reduced immune-status of many patients, this "symbiosis" of free-living amoebae and bacteria might still be of underestimated hospital-hygienic importance.

A bibliography of mental patients' autobiographies: an update and classification system

OBJECTIVE

This article brings to the present earlier bibliographies of books written by former mental patients. These books provide an inside view of mental disorder that can be useful in teaching, public education, theory, and research, and they have played a catalyzing role in mental health reform and in theory development.

METHOD

The authors list seven anthologies and 48 autobiographies of former patients published since 1980 and introduce a classification system intended to increase the research value of this important archive.

RESULTS

Recent books of this genre show more individuals with a mood disorder and more therapists and more women as authors.

CONCLUSIONS

The research potential of these books suggests the value of an electronic database for classifying and retrieving the information they contain.

Social effects on duration in restaurants

A nonreactive observational study in full-service restaurants showed group size to be positively correlated with length of stay. Among the serendipitous findings were the role of reading in lengthening duration and the paucity of lone diners in full-service restaurants.

Increased inactivation of Saccharomyces cerevisiae by protraction of UV irradiation

The principle of equi-effectivity of the product of intensity and exposure time (principle of Bunsen-Roscoe) of UV irradiation has been assumed to be valid for the inactivation of microorganisms in general. Earlier studies claimed higher survival of Escherichia coli B/r with fractionated irradiation compared with single-exposure survival. However, data on the inactivation effect of protraction of UV irradiation are not available. By means of a specially designed UV irradiation apparatus which secured absolute UV dose measurements throughout the experiments, the effects of variation of UV irradiation intensities (253.7 nm) and exposure times were tested on the inactivation of a bacterial virus (Staphylococcus aureus phage A994), a vegetative bacterial strain (E. coli ATCC 25922), and bacterial spores (Bacillus subtilis ATCC 6633) as well as three haploid laboratory strains (RC43a, YNN281, and YNN282) and two diploid strains (commercial bakery yeast strain and laboratory strain YNN281 x YNN282) or yeast (Saccharomyces cerevisiae) and spores of the latter diploid yeast strain. Each test organism was exposed to three UV intensities (0.02, 0.2, and 2 W/m2), with corresponding exposure times resulting in three dose levels for each intensity. Differences in inactivation rates were tested by analyses of variance and Newman-Keuls tests. Virus and bacteria showed no differences in inactivation rates by variation of intensities and exposure times within selected UV doses; hence, the principle of Bunsen-Roscoe could not be rejected for these strains. However, in the eukaryotic test strains of S. cerevisiae longer exposure times with lower intensities led to enhanced inactivation in both haploid and diploid strains, with a more pronounced effect in the diploid yeast strains, whereas in yeast spores in this dose rate effect could not be observed.

Conserved and divergent expression aspects of the Drosophila segmentation gene hunchback in the short germ band embryo of the flour beetle Tribolium

The segmentation gene hunchback (hb) plays a central role in determining the anterior-posterior pattern in the Drosophila embryo. We have cloned the homologue of hb from the flour beetle Tribolium and show that, on the basis of its expression pattern, most of its functions seem to be conserved between these two species. Like Drosophila, Tribolium has a maternal hb expression that appears to be under translational control by a factor at the posterior pole of the embryo. The maternal expression is followed by a zygotic expression in the region of the developing head and thoracic segments. During germ band extension, a posterior expression domain appears that is likely to be homologous to the posterior blastoderm expression of hb in Drosophila. These observations suggest that hb may have the same functions in early Drosophila and Tribolium development, despite the different types of embryogenesis in these two species (long versus short germ development). One differing aspect of hb expression in Tribolium concerns a structure that is not present in Drosophila, namely the serosa. An hb expression domain at the anterior pole precisely demarcates the border between the extraembryonic serosa and the embryonic field in the Tribolium embryo at an early stage, and hb protein remains expressed in the serosa cells until the end of embryogenesis.

Enhanced clastogenicity of contaminated groundwater following UV irradiation detected by the Tradescantia micronucleus assay

The Tradescantia micronucleus (Trad-MCN) assay was used to determine clastogenic effects of contaminated groundwater collected near a hazardous waste landfill. Water samples were taken from a purification plant (activated charcoal filtration, UV irradiation) which was built to avoid groundwater contamination by this landfill. Five series of experiments were conducted during approximately 4 months. In addition, water samples were irradiated under laboratory conditions with increasing doses of UV light. Several field water samples gave positive, dose-dependent effects before filtration and irradiation. Maximal values (6.1 +/- 4.7 micronuclei (MCN)/100 tetrads) were six-fold above controls. UV irradiation of activated charcoal-filtered water resulted in an enhancement of MCN frequencies. Exposure of groundwater to UV irradiation in the laboratory led to a dose-dependent increase of micronuclei. At the highest dose (1500 J/m2) the MCN frequency was more than six times higher than in the unirradiated sample (5.4 +/- 1.0 vs. 0.8 +/- 0.4 MCN/100 tetrads). The clastogenicity of UV-irradiated samples decreased with a half-life of approximately 1 day. Irradiation of tap water did not increase the MCN frequency. Our results indicate that irradiation of water with UV light for disinfection purposes might lead to a transiently increased genotoxicity of chemically polluted water samples.

Massive digitoxin intoxication treated with digoxin-specific antibodies in a child

A 20-month-old girl with massive digitoxin intoxication (initial digitoxin serum level: 629 ng/ml) was successfully treated with digoxin-specific antibody fragments (Fab). She presented with moderate signs of digitalis toxicity (somnolence, bradycardia, first-degree AV block) and improved rapidly during fractional Fab administration. Free serum-digitoxin disappeared after 6 vials of Fab (480 mg), but was measurable again on days 6 and 7. This case demonstrated that digoxin-specific antibodies, despite a 30-100 times lesser affinity for digitoxin, are effective in massive digitoxin intoxications. A rebound phenomenon may occur several days later and should be taken into consideration.