Investigation of a scabies outbreak in a kindergarten in Constance, Germany.

In industrialized countries, scabies occurs sporadically or in the form of protracted epidemics, typically in nursing homes for elderly people. Outbreaks of scabies in a kindergarten are very rare. The main goal of our study was to investigate an outbreak of scabies in a kindergarten and to identify risk factors for the infestation with the ectoparasitosis. We investigated an outbreak of scabies in a kindergarten in the City of Constance, southern Germany, with a particular pedagogical concept. Risk factors indicating a transmission of Sarcoptes mites through body contact or via fomites were assessed using questionnaires and by following the daily routine in the kindergarten. A total of 16 cases were identified. The attack rate was significantly higher in nursery teachers (risk ratio 42.1) compared to children (risk ratio 10.5). In all cases, scabies had developed rather recently, with minimal clinical manifestations. In nursery teachers, the probability of scabies was 4.4 times higher in those teachers who hugged children regularly. Children who preferably played with their own soft toys had a lower probability of developing scabies [risk ratio 0.14, 95 % confidence interval (CI) 0.05-0.42; p = 0.04]. It seems conceivable that the particular pedagogical concept of the kindergarten favored the spread of Sarcoptes mites. We were unable to show whether transmission had preferably occurred through body contact or via fomites.

Molecular and structural effects of inverse agonistic mutations on signaling of the thyrotropin receptor--a basally active GPCR.

Several mutations that decrease the basal signaling activity of G-protein coupled receptors (GPCRs) with pathogenic implications are known. Here we study the molecular mechanisms responsible for this phenotype and investigate how basal and further activated receptor conformations are interrelated. In the basally active thyroid stimulating hormone receptor (TSHR) we combined spatially-distant mutations with opposing effects on basal activity in double-mutations and characterized mutant basal and TSH induced signaling. Mutations lowering basal activity always have a suppressive influence on TSH induced signaling and on constitutively activating mutations (CAMs). Our results suggest that the conformation of a basally 'silenced' GPCR might impair its intrinsic capacity for signaling compared to the wild-type. Striking differences in conformation and intramolecular interactions between TSHR models built using the crystal structures of inactive rhodopsin and partially active opsin help illuminate the molecular details underlying mutations decreasing basal activity.

Detection of Campylobacter jejuni from the skin of broiler chickens, ducks, squab, quail, and guinea fowl carcasses.

Campylobacter jejuni is often found on broiler carcasses and can cause gastroenteritis in humans. Both carcass rinses and swabs of the skin have been utilized to ascertain the prevalence of C. jejuni in the processing plant. Not all poultry commodities are equally capable of carrying C. jejuni on the carcass skin. Our objective was to measure the probability of C. jejuni detection (sensitivity) for the skin swabbing method followed by enrichment in semisolid media, and to ascertain the sensitivity of this method for commercial broiler, duck, squab, quail, and guinea fowl. The probability of detecting skin contaminated with C. jejuni was significantly higher for broiler chicken compared to retail duck, squab, quail, or guinea fowl for 10 or 100 colony-forming units (CFU)/in2 of skin (1 in2 = 1 square inch = 2.5 x 2.5 cm). Thirty-three percent (10 CFU/in2) and 100% (100 CFU/in2) of skin samples from broilers were positive for C. jejuni at the levels inoculated while 7-20% and 47-80% of skin samples were detected as contaminated with C. jejuni at 10 or 100 CFU/in2 for retail duck, squab, quail, and guinea fowl, respectively. Our method of using skin swabs and enrichment with semisolid media generated a sensitivity of almost 100% for detecting C. jejuni at 1000 or 10,000 CFU/in2 skin regardless of poultry species. The level of contamination that our method could detect with 50% and 90% reliability (DT50 and DT90) was 14 and 79 (broilers); 67 and 406 (squab); 39 and 226 (quail); 69 and 400 (guinea fowl); 69 and 400 (duck) CFU/in2 of skin, respectively.

The DXD motif is required for GM2 synthase activity but is not critical for nucleotide binding.

We tested the importance of the aspartate-any residue-aspartate (DXD) motif for the enzymatic activity and nucleotide binding capacity of the Golgi glycosyltransferase GM2 synthase. We prepared point mutations of the motif, which is found in the sequence 352-VLWVDDDFV, and analyzed cells that stably expressed the mutated proteins. Whereas the folding of the mutated proteins was not seriously disrupted as judged by assembly into homodimers, Golgi localization, and secretion of a soluble form of the enzyme, exchange of the highly conserved aspartic acid residues at position 356 or 358 with alanine or asparagine reduced enzyme activity to background levels. In contrast, the D356E and D357N mutations retained weak activity, while the activity of V352A and W354A mutants was 167% and 24% that of wild-type enzyme, respectively. Despite the major effect of the DXD motif on enzymatic activity, nucleotide binding was not altered in the triple mutant D356N/D357N/D358N as revealed by binding to UDP-beads and labeling with the photoaffinity reagent, P(3)-(4-azidoanilido)uridine 5'-triphosphate (AAUTP). In summary, rather than being critical for nucleotide binding, this motif may function during catalysis in GM2 synthase, as has been proposed elsewhere for the SpsA glycosyltransferase based on its crystal structure.

Evidence supporting a late Golgi location for lactosylceramide to ganglioside GM3 conversion.

Ganglioside GM2 synthase and other enzymes required for complex ganglioside synthesis were localized recently to the trans Golgi network (TGN). However, there are conflicting reports as to the location of GM3 synthase; originally this enzyme was detected in the early Golgi of rat liver but a recent report localized it to the late Golgi. We have used chimeric forms of ganglioside GM2 synthase to determine if the location of lactosylceramide (LacCer) to GM3 conversion in Chinese hamster ovary (CHO) cells was the early or late Golgi. Our approach tested whether GM3 could be utilized as a substrate by GM2 synthase chimeras which were targeted to compartments earlier than the trans Golgi, i.e., GM3 produced in the cis Golgi should be utilized by GM2 synthase located anywhere in the Golgi whereas GM3 produced in the trans Golgi should only be used by GM2 synthase located in the trans Golgi or TGN. Comparison of cell lines stably expressing these chimeras revealed that the in vivo functional activity of GM2 synthase decreased progressively as the enzyme was targeted to earlier compartments; specifically, the percentage of GM3 converted to GM2 was 83-86% for wild type enzyme, 70% for the medial Golgi targeted enzyme, 13% for the ER and cis Golgi targeted enzyme, and only 1.7% for the ER targeted enzyme. Thus, these data are consistent with a late Golgi location for LacCer to GM3 conversion in these cells.

Synthesis of fluorescently labeled alkylated DNA adduct standards and separation by capillary electrophoresis.

DNA adducts are regarded as individual internal dosimeters for the exposure to chemical carcinogens. To date, the most sensitive method for DNA adduct analysis is the radioactive 32P-postlabeling method, which allows the detection of one adduct in 10(10) unmodified nucleotides in microg amounts of DNA. However, this technique suffers from disadvantages such as working with radioactive phosphorus and time-consuming chromatographic separation procedures. In addition, the simultaneous detection of adducts from different classes of carcinogens in a DNA sample is difficult. In order to overcome these drawbacks, we are developing a new detection method, comprising fluorescence labeling of DNA adducts, capillary electrophoretic (CE) separation, and on-line detection by monitoring laser-induced fluorescence (LIF). So far, we have evaluated the separation power and the detection limit of CE with fluorescently labeled standard compounds such as unmodified nucleotides or alkylated thymidines. For this purpose, we developed a universal method for labeling 5'-OH-mononucleosid-3'-dicyanoethyl-phosphates with fluorescent dyes based on the phosphoramidite technology for DNA synthesis. The separation of N3-methylated, N3-, O2- and O4-butylated thymidines from the unmodified nucleotide within a few minutes recommends CE-LIF as a powerful method for DNA adduct analysis.

Analysis of catechins and caffeine in tea extracts by micellar electrokinetic chromatography.

Cancer chemotherapy is a new and important medical science and much interest has been focused on catechins, not only for their antioxidant activity, but also because of their known antimutagenic and antitumorigenic properties. Green tea and black tea, which are among the most popular beverages consumed worldwide, contain many different catechins. We developed an analytical method capable of separating six different catechins and caffeine in tea by micellar electrokinetic chromatography in only 20 min without extensive sample preparation. Furthermore, we compared the amount of catechins and caffeine in several teas and different preparation modes.

Two soluble glycosyltransferases glycosylate less efficiently in vivo than their membrane bound counterparts.

Many Golgi glycosyltransferases are type II membrane proteins which are cleaved to produce soluble forms that are released from cells. Cho and Cummings recently reported that a soluble form of alpha1, 3-galactosyltransferase was comparable to its membrane bound counterpart in its ability to galactosylate newly synthesized glycoproteins (Cho,S.K. and Cummings,R.D. (1997) J. Biol. Chem., 272, 13622-13628). To test the generality of their findings, we compared the activities of the full length and soluble forms of two such glycosyltransferases, ss1,4 N-Acetylgalactosaminyltransferase (GM2/GD2/ GA2 synthase; GalNAcT) and beta galactoside alpha2,6 sialyltransferase (alpha2,6-ST; ST6Gal I), for production of their glycoconjugate products in vivo . Unlike the full length form of GalNAcT which produced ganglioside GM2 in transfected cells, soluble GalNAcT did not produce detectable GM2 in vivo even though it possessed in vitro GalNAcT activity comparable to that of full length GalNAcT. When compared with cells expressing full length alpha2,6-ST, cells expressing a soluble form of alpha2,6-ST contained 3-fold higher alpha2,6-ST mRNA levels and secreted 7-fold greater alpha2,6-ST activity as measured in vitro , but in striking contrast contained 2- to 4-fold less of the alpha2,6-linked sialic acid moiety in cellular glycoproteins in vivo . In summary these results suggest that unlike alpha1,3-galactosyltransferase the soluble forms of these two glycosyltransferases are less efficient at glycosylation of membrane proteins and lipids in vivo than their membrane bound counterparts.

Leukocyte transmembrane potential in bipolar illness.

Abnormalities in ion regulation and distribution are commonly reported in bipolar disorder. In an effort to determine if these alter cellular physiological function, we determined the transmembrane potential (TMP) in mononuclear leukocytes from normal individuals and patients with bipolar illness either during normal phase or manic and hypomanic episodes. TMP was analyzed by flow cytometry using dihexyloxacarbocyanine iodide (DIOC6(3)), a cationic potential sensitive fluorescent dye. A normal range was established from measurements on leukocytes from 5 control individuals. TMP of manic and hypomanic patients was significantly hyperpolarized (P = 0.0036). The TMP of euthymic bipolar individuals was not different from normal controls. Pathologic moods in bipolar illness may be associated with altered cellular membrane physiology.

Understanding differences between high and low childhood accident rate areas: the importance of qualitative data.

BACKGROUND: The research discussed in the paper was undertaken for a District Health Authority to aid the development of appropriate policies to achieve the Health of the nation strategic target for reducing the death rate from accidents amongst children under 15. There has been a great deal of quantitative and epidemiological research into childhood accidents which has demonstrated a clear social class gradient in childhood accidents, fatalities and injuries. Less research has been undertaken into the possible reasons for the 'social patterning' of accidents and other aspects of health. Recent sociological research on childhood accidents has adopted a more qualitative approach and studied childhood safety within a family and community context. This approach has been used in the Huddersfield study on parental perspectives on childhood safety. METHODS: In-depth interviews were held with a sample of parents from a high and a low childhood accident rate area. RESULTS: The two focus areas reveal contrasting social profiles. There were significant differences on a number of aspects of parental perceptions on safety and beliefs about accidents, in the two areas. Analysis of accident events revealed that all the families in the high childhood accident rate area sample had children who had had an accident in the past which required hospital treatment. A high proportion of their children had experienced 'near misses'. In contrast, half the families in the low childhood accident rate area had children who had experienced an accident in the past and a much smaller proportion had experienced 'near misses'. All the parents in the sample from both areas developed rules, routines and practices to keep their children safe. The study suggests that there are social class differences in the effective use of these safety rules. CONCLUSION: Qualitatively orientated sociological research into parental perspectives on childhood safety contributes to an understanding of the reasons for the social patterning of childhood accidents. Such information should be of help to professionals in their prevention and safety promotion work.

Cytometric detection of DNA amplified with fluorescent primers: applications to analysis of clonal bcl-2 and IgH gene rearrangements in malignant lymphomas.

Follicular lymphomas comprise almost two thirds of the US adult non-Hodgkin's lymphomas (NHL) and are the most common malignancy of B-lineage lymphocytes. Polymerase chain reaction (PCR) protocols have been developed to detect the t(14;18) translocation, which juxtaposes the bcl-2 proto-oncogene to the Ig heavy-chain (IgH) gene in 85% of follicular lymphomas and monoclonal rearrangements of the IgH gene in B-cell NHL that lack bcl-2 rearrangements. We used PCR to amplify bcl-2 and IgH rearrangements in DNA from patients with lymphoproliferative disorders and analyzed the products in parallel by gel electrophoresis and flow cytometry, which detected PCR products incorporating fluoresceinated oligonucleotide primers by sequence-specific capture to oligonucleotide-coated magnetic beads. Overall, flow cytometry was superior to electrophoresis of ethidium-bromide-stained agarose gels for detection of products of nested PCR to detect intergenic rearrangements involving bcl-2 and single primer-pair amplification of clonal rearrangement of IgH. Flow cytometric analysis detected bcl-2 translocations in 12 of 13 CD10+ B-cell lymphomas and clonal IgH rearrangements in 14 of 17 monoclonal B-cell populations. In contrast, analysis by gel electrophoresis detected bcl-2 translocations in only 10 of 13 CD10+ and clonal IgH gene rearrangements in only 9 of 17 monoclonal B-cell populations. Flow cytometric analysis was more sensitive than gel electrophoresis and could detect a 16-fold greater dilution of a bcl-2-amplified product than gel electrophoresis. Similarly, flow cytometry could detect an amplification product when template DNA was diluted 10,000-fold, whereas gel electrophoresis only detected amplification products when template was subjected to dilution between 100- and 1,000-fold. This shows the utility of flow cytometry for the analysis of DNA amplification products incorporating fluorochrome-labeled primers as a rapid, objective alternative to conventional strategies. Because current-generation clinical laboratories emphasize automation, flow cytometric analysis of PCR-amplified products shows increased analytic sensitivity and offers a vehicle for automation of DNA amplification tests.

A study of 'inappropriate' attendances to a paediatric Accident and Emergency Department.

'Inappropriate' attendance to Accident and Emergency Departments (AEDs) has been shown in many studies to be a sizeable problem. However, only one previous study has investigated inappropriate attendance to these departments amongst children. In this paper we report an investigation of 'inappropriate' usage of a children's AED in Nottingham. Information was collected relating to a representative sample of children who attended this department during September and October 1989 by interviewing the adults accompanying them to the AED and by examining the children's AED medical records. Using defined criteria, the doctors treating each child within the AED assessed whether their attendance was 'appropriate' to the department. Nearly a third (30.1 per cent) of the patients studied were subsequently considered to be inappropriate attenders to this department. This proportion was highest amongst younger children, those from families of lower social class and those living closest to the hospital. 'Inappropriate' attendance was not found to relate to the availability of general practitioners. The reasons stated for choosing to attend the AED suggested that these attendances resulted from perceptions of the adult(s) accompanying the children to the department. In view of this finding, action is required to correct these perceptions, although it is recognized that this may be difficult to achieve.

The relationship among multiple assessments of nursing education outcomes.

Three internal and three external outcome measures generated data for this longitudinal study. The internal outcome measures were nursing GPA, nonnursing GPA, and clinical evaluations of students during eight clinical rotations. The external evaluations were NCLEX scores, the graduates' self-rating of their competency in meeting program objectives, and their immediate supervisors' ratings on the identical competency rating scale. Data analyzed using Pearson correlation coefficients revealed significant correlations among all internal measures of academic outcomes with one external measure, the NCLEX score. There was no correlation between any nursing measure of outcome and the supervisor's ratings. There was a modest correlation between the supervisors' rating and the nonnursing GPA. The faculty clinical evaluation was the only significant correlation found between the alumni rankings and any other measure of outcome. There was no correlation between the supervisors' and the graduates' ratings.

Retention of English-as-a-second-language (ESL) students: approaches used by California's 21 generic baccalaureate nursing programs.

A rapidly growing number of California's ethnic minority nursing students are individuals whose primary language is not English; these English-as-a-second-language (ESL) students often have high attrition rates. This research surveys the approaches used in all of California's 21 generic baccalaureate nursing programs to retain their ESL students until graduation. Comparisons between the five programs with the highest ESL student retention rates and the group as a whole show significant differences.

Baccalaureate student nurse success prediction: a replication.

The use of group testing that predicts success in understanding and using the nursing process suggests a tempting solution to a vexing problem: selecting those students from an applicant pool who have the potential to successfully complete a nursing program. Failure to replicate or extend previous studies has been recognized as a major limitation in nursing research (Brown, Tanner, & Padrick, 1984). The purpose of this research was to replicate a study using a set of four short test instruments identified as being successful predictors (Kissinger & Munjas, 1982). As part of a larger research project, four successive classes of students admitted to the school of nursing (N = 155) were tested and followed over a 4 1/2-year period with 100% participation. The results were not supportive of the findings in the previous study. The importance of cross validation of prediction studies, as well as the need for periodic sampling of previously validated prediction batteries due to changing elements in selection programs, was demonstrated. The study's outcome and the nursing literature suggest that some configuration of prerequisite grade point average, with all of its limitations and student manipulations, and a required verbal SAT/ACT score may still be the most efficient predictors available to admission committees in schools of nursing.