Developing Dictyostelium discoideum amoebae form a stalked fruiting body in which individual cells differentiate into either stalk cells or spores. The major known inducer of stalk cell differentiation is the chlorinated polyketide DIF-1 (1-(3,5-dichloro-2,6-dihydroxy-4-methoxyphenyl)hexan-1-one); however a mutant blocked in the terminal step of DIF-1 biosynthesis still produces one of the prestalk cell subtypes - the pstA cells - as well as some mature stalk cells. We therefore searched for additional stalk cell-inducing factors in the medium supporting development of this mutant. These factors were purified by solvent extraction and HPLC and identified by mass spectroscopy and NMR. The mutant lacked detectable DIF-2 and DIF-3 (the pentanone and deschloro homologues of DIF-1) but four major stalk cell-inducing activities were detected, of which three were identified. Two compounds were predicted intermediates in DIF-1 biosynthesis: the desmethyl, and desmethyl-monochloro analogues of DIF-1 (dM-DIF-1 and Cl-THPH, respectively), supporting the previously proposed pathway of DIF-1 biosynthesis. The third compound was a novel factor and was identified as 4-methyl-5-pentylbenzene-1,3-diol (MPBD) with the structure confirmed by chemical synthesis. To investigate the potential roles of these compounds as signal molecules, their effects on morphological stalk and spore differentiation were examined in cell culture. All three induced morphological stalk cell differentiation. We found that synthetic MPBD also stimulated spore cell differentiation. Now that these factors are known to be produced and released during development, their biological roles can be pursued further.

BACKGROUND

In frontal fibrosing alopecia (FFA), scalp alopecia dominates the clinical picture. However, eyebrow loss and hair loss in other body sites may also occur; this has been documented clinically, but rarely histopathologically. We describe the clinicopathological findings of 13 cases of FFA, with histopathologic data from the scalp, eyebrow, and body hair.

METHODS

Thirteen patients with a diagnosis of FFA, seen between 2006 and 2008, were included. Scalp biopsies were performed in all patients for histology and direct immunofluorescence (DIF). Biopsy specimens for histology were taken from the eyebrow in 6 patients and from the upper limb in 5 patients.

RESULTS

All 13 patients were female, 11 of whom were postmenopausal. The median age at onset of alopecia was 57 years. Clinical examination revealed a band of frontal hairline recession in all patients. Eyebrow loss was present clinically in all patients, with loss of body hair in 10 of 13. Histopathologic examination of the scalp, eyebrow, and upper limb skin biopsy specimens showed similar features, including a marked reduction in the number of hair follicles and a perifollicular lymphoid cell infiltrate with perifollicular fibrosis. Direct immunofluorescence was negative in all cases.

CONCLUSIONS

Not all patients consented to biopsies of the eyebrows or upper limbs.

CONCLUSIONS

Eyebrow and peripheral body hair loss is not uncommon in FFA-a finding that is likely underreported. We have demonstrated that alopecia of the upper limbs in FFA is indeed common and, histopathologically, shows features of lichen planopilaris and scarring, similar to findings in the scalp and eyebrows. Consequently, the process of lichen planopilaris with scarring alopecia is generalized rather than localized only to the frontal scalp and eyebrows.

One poorly understood mechanism of developmental patterning involves the intermingled differentiation of different cell types that then sort out to generate pattern. Examples of this are known in nematodes and vertebrates, and in Dictyostelium it is the major mechanism. However, a general problem with this mechanism is the possibility that different inducers are required for each cell type that arises independently of positional information. Consistent with this idea, in Dictyostelium the signalling molecule DIF acts as a position-independent signal and was thought only to regulate the differentiation of a single cell type (pstO). The results presented here challenge this idea. In a novel genetic selection to isolate genes required for DIF signal transduction, we found a mutant (dimC(-)) that is a hypomorphic allele of a GATA family transcription factor (gtaC). gtaC expression is directly regulated by DIF, and GtaC rapidly translocates to the nucleus in response to DIF. gtaC(-) null cells showed some hallmark DIF signalling defects. Surprisingly, other aspects of the mutant were distinct from those of other DIF signalling mutants, suggesting that gtaC regulates a subset of DIF responses. For example, pstO cell differentiation appeared normal. However, we found that pstB cells were mislocalised and the pstB-derived basal disc was much reduced or missing. These defects are due to a failure to respond to DIF as they are phenocopied in other DIF signalling mutants. These findings therefore identify a novel small-molecule-activated GATA factor that is required to regulate the cell type-specific effects of DIF. They also reveal that a non-positional signal can regulate the differentiation of multiple cell types through differential interpretation in receiving cells.

In bacteria with multiple sets of chemotaxis genes, the deletion of homologous genes or even different genes in the same operon can result in disparate phenotypes. Myxococcus xanthus is a bacterium with multiple sets of chemotaxis genes and/or homologues. It was shown previously that difA and difE, encoding homologues of the methyl-accepting chemoreceptor protein (MCP) and the CheA kinase, respectively, are required for M. xanthus social gliding (S) motility and development. Both difA and difE mutants were also defective in the biogenesis of the cell surface appendages known as extracellular matrix fibrils. In this study, we investigated the roles of the CheW homologue encoded by difC, a gene at the same locus as difA and difE. We showed that difC mutations resulted in defects in M. xanthus developmental aggregation, sporulation, and S motility. We demonstrated that difC is indispensable for wild-type cellular cohesion and fibril biogenesis but not for pilus production. We further illustrated the ectopic complementation of a difC in-frame deletion by a wild-type difC. The identical phenotypes of difA, difC, and difE mutants are consistent and supportive of the hypothesis that the Dif chemotaxis homologues constitute a chemotaxis-like signal transduction pathway that regulates M. xanthus fibril biogenesis and S motility.

The septum-located DNA translocase, FtsK, acts to co-ordinate the late steps of Escherichia coli chromosome segregation with cell division. The FtsK gamma regulatory subdomain interacts with 8 bp KOPS DNA sequences, which are oriented from the replication origin to the terminus region (ter) in each arm of the chromosome. This interaction directs FtsK translocation towards ter where the final chromosome unlinking by decatenation and chromosome dimer resolution occurs. Chromosome dimer resolution requires FtsK translocation along DNA and its interaction with the XerCD recombinase bound to the recombination site, dif, located within ter. The frequency of chromosome dimer formation is approximately 15% per generation in wild-type cells. Here we characterize FtsK alleles that no longer recognize KOPS, yet are proficient for translocation and chromosome dimer resolution. Non-directed FtsK translocation leads to a small reduction in fitness in otherwise normal cell populations, as a consequence of approximately 70% of chromosome dimers being resolved to monomers. More serious consequences arise when chromosome dimer formation is increased, or their resolution efficiency is impaired because of defects in chromosome organization and processing. For example, when Cre-loxP recombination replaces XerCD-dif recombination in dimer resolution, when functional MukBEF is absent, or when replication terminates away from ter.

OBJECTIVE

Item-response theory is increasingly used in the development of robust measurement tools. The extent to which the Health Assessment Questionnaire (HAQ) disability index (DI) and Short Form 36 (SF-36) physical functioning subscale (PF) fit a Rasch model in psoriatic arthritis (PsA) is uncertain. Our objective was to compare the psychometric properties of the HAQ DI and SF-36 PF in PsA and rheumatoid arthritis (RA) using Rasch analysis.

METHODS

Patients with RA (n = 142) and PsA (n = 134) were identified from a disease register based at a regional rheumatology service that serves a population of approximately 400,000 individuals. Responses to the HAQ DI and SF-36 PF were analyzed for item fit, differential item functioning (DIF), scale length (item separation), floor effects, and item difficulty by fitting the data to a Rasch model. The extent to which each instrument measured the same concept (disability) was also assessed in the PsA cohort using the Rasch model.

RESULTS

Item separation was much better for the SF-36 PF than the HAQ DI in PsA (9.12 logits versus 2.06 logits). There was evidence of marked DIF for the HAQ DI items activities, grip, and rising and relatively minor DIF for 4 items of the SF-36 PF. The distribution of SF-36 PF was better than HAQ DI in PsA, with floor effects of 3.1% versus 30.4%. Common person equating demonstrated that the 2 instruments measure the same construct in PsA.

CONCLUSIONS

The SF-36 PF has significant psychometric advantages over the HAQ DI in PsA.

OBJECTIVE

We review the papers presented at the NCI/DIA conference, to identify areas of controversy and uncertainty, and to highlight those aspects of item response theory (IRT) and computer adaptive testing (CAT) that require theoretical or empirical research in order to justify their application to patient reported outcomes (PROs).

BACKGROUND

IRT and CAT offer exciting potential for the development of a new generation of PRO instruments. However, most of the research into these techniques has been in non-healthcare settings, notably in education. Educational tests are very different from PRO instruments, and consequently problematic issues arise when adapting IRT and CAT to healthcare research.

RESULTS

Clinical scales differ appreciably from educational tests, and symptoms have characteristics distinctly different from examination questions. This affects the transferring of IRT technology. Particular areas of concern when applying IRT to PROs include inadequate software, difficulties in selecting models and communicating results, insufficient testing of local independence and other assumptions, and a need of guidelines for estimating sample size requirements. Similar concerns apply to differential item functioning (DIF), which is an important application of IRT. Multidimensional IRT is likely to be advantageous only for closely related PRO dimensions.

CONCLUSIONS

Although IRT and CAT provide appreciable potential benefits, there is a need for circumspection. Not all PRO scales are necessarily appropriate targets for this methodology. Traditional psychometric methods, and especially qualitative methods, continue to have an important role alongside IRT. Research should be funded to address the specific concerns that have been identified.

OBJECTIVE

The 20-item Toronto Alexithymia Scale (TAS-20) measures three intercorrelated dimensions of alexithymia: (1) difficulties identifying feelings (DIF), (2) difficulties describing feelings (DDF), and (3) externally oriented thinking (EOT). The aim of the study was to test the three-factor model of the TAS-20 using confirmatory factorial analyses (CFA).

METHODS

769 healthy subjects and 659 patients meeting the DSM-IV criteria for substance use disorders or eating disorders completed the TAS-20. The correlation matrices for each of the samples were analyzed with LISREL 7.16.

RESULTS

In each sample, the three-factor model was found to be replicable.

CONCLUSIONS

The three TAS-20 subcales can be used to explore the distinct facets of the alexithymia construct.

An item with differential item functioning (DIF) displays different statistical properties, conditional on a matching variable. The presence of DIF in measures can invalidate the conclusions of medical outcome studies. Numerous approaches have been developed to examine DIF in many areas, including education and health-related quality of life. There is little consensus in the research community regarding selection of one best method, and most methods require large sample sizes. This article describes some approaches to examine DIF with small samples (e.g., less than 200).

Differential item functioning (DIF) attempts to identify items for which subpopulations of examinees exhibit performance differentials that are not consistent with the performance differentials seen among those subpopulations on a reliable measure of the construct of interest. DIF assessment requires a rule for scoring items and a matching variable on which different subpopulations can be viewed as comparable for purposes of assessing their performance on items. Typically, DIF is operationally defined as a difference in item performance between subpopulations, eg, Spanish-speakers and English-speakers, which exist after members of the different subpopulations have been matched on some one-dimensional matching variable such as total score. This work defines DIF, describes 2 standard procedures for measuring DIF, applies these DIF procedures to the Mini-Mental State Examination, and contrasts DIF with score equity analysis (SEA). The description of DIF assessment presented in this paper is applicable to any examination question that has responses that can be ordered, eg, with respect to correctness or severity.

The pcsA68 mutant of Escherichia coli is a cold-sensitive mutant which forms long filaments with a large nucleoid in the central region at 20 degrees C. We here show that (i) the coding region for the pcsA gene is identical with orfY located upstream of pyrE and can be deleted without loss of viability; (ii) pcsA is also identical to dinD, a DNA damage-inducible gene, whose expression is regulated by the LexA-RecA system; (iii) the cold-sensitive phenotype of the pcsA68 mutation is suppressed by delta recA or lexA1 (Ind-) mutation, but not by sulA inactivation; (iv) overproduction of PcsA68 leads to inhibition of cell growth in recA+ and delta recA strains at 20 and 37 degrees C, but PcsA+ does not show such an effect at any temperature; (v) SOS response is induced in the pcsA68 mutant cells at 20 degrees C. We discuss the possible function of the pcsA gene, comparing it with the sulA or the dif-xerCD function. We also describe a new method for gene disruption with positive and negative selection.

We summarize studies on stalk and spore cell formation in D. discoideum cell monolayers, aimed at revealing factors involved in controlling the prestalk:prespore pattern in this organism. We propose that there are no cell interactions dependent on cell contact per se. Formation of mature stalk cells from isolated amoebae incubated in a buffered salts medium requires only cyclic AMP and a lipid-like factor (DIF) released by cells developing at high density. In addition, a variety of sporogenous mutants can form spores rapidly and efficiently when incubated at low density in tissue culture dishes containing a similar cyclic AMP and salts medium. In some cases spore formation is improved by the addition of one or other of a variety of protective agents such as bovine serum albumin. Wild-type amoebae at low density form prespore cells under the same conditions. We present some evidence that DIF is the activator of prestalk cell formation in a two-component patterning mechanism of the kind proposed by Wolpert et al. (Symp. Soc. exp. Biol. 25, 391-415 (1971)) and Gierer & Meinhardt (Kybernetik 12, 30-39 (1972)). We also provide data indicating that the role of inhibitor is played by ammonia, an idea first mooted by Sussman & Schindler (Differentiation 10, 1-5 (1978)).

In Drosophila, bacterial challenge induces the rapid transcription of several genes encoding potent antibacterial peptides. The upstream sequences of the diptericin and cecropin Al genes, which have been investigated in detail, contain two, respectively one sequence element homologous to the binding site of the mammalian nuclear factor kappaB. These elements have been shown to be mandatory for immune-induced transcription of both genes. Functional studies have shown that these kappaB-related elements can be the target for the Drosophila Rel proteins dorsal and Dif. Here we present a comparative analysis of the transactivating capacities of these proteins on reporter genes fused to either the diptericin or the cecropin kappaB-related motifs. We conclude from our results: (i) the kappaB motifs of the diptericin and cecropin genes are not functionally equivalent; (ii) the dorsal and Dif proteins have distinct DNA-binding characteristics; (iii) dorsal and Dif can heterodimerize in vitro; (iv) mutants containing no copies of dorsal and a single copy of Dif retain their full capacity to express the diptericin and cecropin genes in response to challenge.

OBJECTIVE

Alexithymia, a lack of emotional awareness, is common in chronic pain patients. The aim of the study was to investigate the relationship of alexithymia to ongoing pain, experimental pain sensitivity, and illness behavior in patients with chronic musculoskeletal pain.

METHODS

Sixty-eight women with fibromyalgia (age: average, 43.4 years; range, 19-72 years) completed self-report measures on alexithymia (20-Item Toronto Alexithymia Scale), ongoing pain [Visual Analogue Scale, Questionario Italiano del Dolore (QUID), Margolis], psychological distress (Center for Epidemiology Studies-Depression Scale, State-Trait Anxiety Inventory Form Y), and illness behavior (Illness Behavior Questionnaire). Psychophysical tests were performed to assess experimental pain sensitivity, including pain thresholds for mechanical (von Frey, tender point count) and thermal (heat, cold) stimuli, and cold pressor pain threshold and tolerance.

RESULTS

Alexithymia "difficulty identifying feelings" (DIF) was related to higher ratings of the affective-but not the sensory-dimensions of ongoing pain (QUID) and to a lower cold pressor pain tolerance, while alexithymia scores were independent of all pain thresholds. Multiple regression demonstrated that alexithymia DIF ceased to uniquely predict affective ongoing pain when psychological distress or illness behavior was separately controlled for. Higher alexithymia DIF scores were predictive of hypochondriacal illness behavior, over and above what was explained by psychological distress and affective pain.

CONCLUSIONS

Alexithymia is associated with increased affective pain and hypochondriacal illness behavior. The former relationship is better explained, and possibly mediated, by psychological distress and illness behavior. The hypothesis of a generally increased sensitivity to unpleasant stimuli in alexithymic chronic pain patients is not supported by the data.

Isolated (A-motile) Myxococcus xanthus cells glide over solid surfaces and display excitation, a suppression of direction reversals, when presented with phosphatidylethanolamine (PE) purified from its own membranes or synthetic dilauroyl PE and dioleoyl PE. Although the mechanism of PE signal transduction is unknown, we hypothesized that M. xanthus might use surface-associated factors to detect exogenous PE to prevent endogenous lipids from self-stimulating the sensory system. Peritrichous protein and polysaccharide appendages called fibrils were correlated with dilauroyl PE excitation. Wild-type cells treated with Congo red, an inhibitor of fibril assembly, and mutants defective in fibril biosynthesis showed an elevated reversal period, which suggested that fibrils regulate the gliding motor. Furthermore, the loss of fibrils resulted in loss of excitation to dilauroyl PE but not dioleoyl PE. Restoration of fibril production to these mutants restored the dilauroyl PE response. In addition, the dif cytoplasmic signal transduction system and starvation conditions were required for dilauroyl PE excitation. The chemically specific nature of the response and the dependence on the dif system suggests that fibrils define a novel sensory organelle whose evolution may have been necessary to prevent autostimulation by endogenous membrane lipids. Because the hydrophobic nature of dilauroyl PE would be inaccessible to periplasmic chemosensors, we suggest that fibrils act as extracellular signal transducers to probe surfaces for insoluble chemical signals.

Differentiation-inducing factors (DIFs) are putative morphogens that induce cell differentiation in Dictyostelium discoideum. We previously reported that DIF-3 activates glycogen synthase kinase-3beta (GSK-3beta), resulting in the degradation of cyclin D1 in HeLa cells. In this study, we investigated the effect of DIF-3 on cyclin D1 mutants (R29Q, L32A, T286A, T288A, and T286A/T288A) to clarify the precise mechanisms by which DIF-3 degrades cyclin D1 in HeLa cells. We revealed that T286A, T288A, and T286A/T288A mutants were resistant to DIF-3-induced degradation compared with wild-type cyclin D1, indicating that the phosphorylation of Thr(286) and Thr(288) were critical for cyclin D1 degradation induced by DIF-3. Indeed, DIF-3 markedly elevated the phosphorylation level of cyclin D1, and mutations introduced to Thr(286) and/or Thr(288) prevented the phosphorylation induced by DIF-3. Depletion of endogenous GSK-3beta and dual-specificity tyrosine phosphorylation regulated kinase 1B (DYRK1B) by RNA interference attenuated the DIF-3-induced cyclin D1 phosphorylation and degradation. The effect of DIF-3 on DYRK1B activity was examined and we found that DIF-3 also activated this kinase. Further, we found that not only GSK-3beta but also DYRK1B modulates cyclin D1 subcellular localization by the phosphorylation of Thr(288). These results suggest that DIF-3 induces degradation of cyclin D1 through the GSK-3beta- and DYRK1B-mediated threonine phosphorylation in HeLa cells.

BACKGROUND

Airway epithelial cells not only constitute a physical barrier, but also the first line of defence against airborne pathogens. At the same time, they are constantly exposed to reactive oxygen species. Therefore, airway epithelia cells have to possess a sophisticated innate immune system and a molecular armamentarium to detoxify reactive oxygen species. It has become apparent that deregulation of epithelial innate immunity is a major reason for the development of chronic inflammatory lung diseases. To elucidate the molecular architecture of the innate immune system of airway epithelial cells, we choose the fruit fly Drosophila melanogaster as a model, because it has the simplest type of airways, consisting of epithelial cells only. Elucidating the structure of the innate immune system of this "airway epithelial cell culture" might enable us to understand why deregulatory processes in innate immune signalling cascades lead to long lasting inflammatory events.

RESULTS

All airway epithelial cells of the fruit fly are able to launch an immune response. They contain only one functional signal transduction pathway that converges onto NF-kappaB factors, namely the IMD-pathway, which is homologous to the TNF-alpha receptor pathway. Although vital parts of the Toll-pathway are missing, dorsal and dif, the NF-kappaB factors dedicated to this signalling system, are present. Other pathways involved in immune regulation, such as the JNK- and the JAK/STAT-pathway, are completely functional in these cells. In addition, most peptidoglycan recognition proteins, representing the almost complete collection of pattern recognition receptors, are part of the epithelial cells equipment. Potential effector molecules are different antimicrobial peptides and lysozymes, but also transferrin that can inhibit bacterial growth through iron-depletion. Reactive oxygen species can be inactivated through the almost complete armamentarium of enzymatic antioxidants that has the fly to its disposal.

CONCLUSIONS

The innate immune system of the fly's airway epithelium has a very peculiar organization. A great variety of pattern recognition receptors as well as of potential effector molecules are conspicuous, whereas signalling presumably occurs through a single NF-kappaB activating pathway. This architecture will allow reacting if confronted with different bacterial or fungal elicitors by activation of a multitude of effectors.

Bacterial FtsK plays a key role in coordinating cell division with the late stages of chromosome segregation. The N-terminal membrane-spanning domain of FtsK is required for cell division, whereas the C-terminal domain is a fast double-stranded DNA (dsDNA) translocase that brings the replication termination region of the chromosome to midcell, where it facilitates chromosome unlinking by activating XerCD-dif site-specific recombination. Therefore, FtsK coordinates the late stages of chromosome segregation with cell division. Although the translocase is known to act as a hexamer on DNA, it is unknown when and how hexamers form, as is the number of FtsK molecules in the cell and within the divisome. Using single-molecule live-cell imaging, we show that newborn Escherichia coli cells growing in minimal medium contain ~40 membrane-bound FtsK molecules that are largely monomeric; the numbers increase proportionately with cell growth. After recruitment to the midcell, FtsK is present only as hexamers. Hexamers are observed in all cells and form before any visible sign of cell constriction. An average of 7 FtsK hexamers per cell are present at midcell, with the N-terminal domain being able to hexamerize independently of the translocase. Detergent-solubilized and purified FtsK N-terminal domains readily form hexamers, as determined by in vitro biochemistry, thereby supporting the in vivo data. The hexameric state of the FtsK N-terminal domain at the division site may facilitate assembly of a functional C-terminal DNA translocase on chromosomal DNA.

OBJECTIVE

In the rod-shaped bacterium Escherichia coli, more than a dozen proteins act at the cell center to mediate cell division, which initiates while chromosome replication and segregation are under way. The protein FtsK coordinates cell division with the late stages of chromosome segregation. The N-terminal part of FtsK is membrane embedded and acts in division, while the C-terminal part forms a hexameric ring on chromosomal DNA, which the DNA can translocate rapidly to finalize chromosome segregation. Using quantitative live-cell imaging, which measures the position and number of FtsK molecules, we show that in all cells, FtsK hexamers form only at the cell center at the initiation of cell division. Furthermore, the FtsK N-terminal portion forms hexamers independently of the C-terminal translocase.

The concept of negative symptoms in methamphetamine (MA) psychosis (e.g., poverty of speech, flatten affect, and loss of drive) is still uncertain. This study aimed to use differential item functioning (DIF) statistical techniques to differentiate the severity of psychotic symptoms between MA psychotic and schizophrenic patients. Data of MA psychotic and schizophrenic patients were those of the participants in the WHO Multi-Site Project on Methamphetamine-Induced Psychosis (or WHO-MAIP study) and the Risperidone Long-Acting Injection in Thai Schizophrenic Patients (or RLAI-Thai study), respectively. To confirm the unidimensionality of psychotic syndromes, we applied the exploratory and confirmatory factor analyses (EFA and CFA) on the eight items of Manchester scale. We conducted the DIF analysis of psychotic symptoms observed in both groups by using nonparametric kernel-smoothing techniques of item response theory. A DIF composite index of 0.30 or greater indicated the difference of symptom severity. The analyses included the data of 168 MA psychotic participants and the baseline data of 169 schizophrenic patients. For both data sets, the EFA and CFA suggested a three-factor model of the psychotic symptoms, including negative syndrome (poverty of speech, psychomotor retardation and flatten/incongruous affect), positive syndrome (delusions, hallucinations and incoherent speech) and anxiety/depression syndrome (anxiety and depression). The DIF composite indexes comparing the severity differences of all eight psychotic symptoms were lower than 0.3. The results suggest that, at the same level of syndrome severity (i.e., negative, positive, and anxiety/depression syndromes), the severity of psychotic symptoms, including the negative ones, observed in MA psychotic and schizophrenic patients are almost the same.

BACKGROUND

Differential item functioning (DIF) analyses can be used to explore translation, cultural, gender or other differences in the performance of quality of life (QoL) instruments. These analyses are commonly performed using "baseline" or pretreatment data. We previously reported DIF analyses to examine the pattern of item responses for translations of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 QoL instrument, using only data collected prior to cancer treatment. We now compare the consistency of these results with similar analyses of on-treatment and off-treatment assessments and explore whether item relationships differ from those at baseline.

METHODS

Logistic regression DIF analyses were used to examine the translation of each item in each multi-item scale at the three time points, after controlling for the overall scale score and other covariates. The consistency of results at the three time points was explored.

RESULTS

For most EORTC QLQ-C30 subscales, the DIF results were very consistent across the three time points. Results for the Nausea and Vomiting scale varied the most across assessments.

CONCLUSIONS

The results indicated that DIF analyses were stable across each time point and that the same DIF effects were usually found regardless of the treatment status of the respondent.

This prospective longitudinal study examined the epidemiology and disease syndrome associated with bovine coronavirus (BCV) infections in a cohort of 8 conventional calves from 0 to 120 days of age, in two dairy herds in Ohio. The periods of respiratory shedding of BCV were determined by direct immunofluorescent (DIF) staining of nasal epithelial cells and ELISA of nasal swab supernatant fluids. The periods of fecal shedding of BCV were determined by ELISA and immunoelectron microscopy (IEM). The isotype-specific antibody titers to BCV in serum (at selected intervals between 0 and 120 days of age) and the post-suckling (24 to 48 h after birth) total immunoglobulin levels were examined by ELISA and zinc sulfate turbidity tests, respectively. Of the 8 calves studied, 4 had evidence of BCV respiratory (by DIF or ELISA) or enteric infections (by IEM or ELISA) in association with diarrhea or rhinitis, even though 7 of 8 calves showed increases in one or more serum antibody isotypes to BCV and 6 of 8 calves showed BCV respiratory or enteric antigen shedding by ELISA. Serological antibody titer increases occurred in 3 calves before 30 days of age and in 4 calves after 30 days of age; two of the latter calves had a second rise in serum antibody titers to BCV after the initial rise. A serological antibody titer increase was not observed in one calf. This suggests that BCV infections may be very common in a closed herd and may occur in older calves, although many may be subclinical and some may be recurrent. There were no statistically significant correlations between total serum immunoglobulin levels or BCV antibody isotype titers in serum (24-48 h after birth) and clinical disease or infection by BCV; however, calves with low levels of IgA BCV antibodies in serum (24-48 h after birth) had a significantly greater average number of days with diarrhea than those calves having high levels of IgA BCV-specific antibodies in serum.

Dihydropyrimidine dehydrogenase (DPD) is the initial, rate-limiting enzyme in the catabolism of 5-fluorouracil (5-FU). DPD has an important role in regulating the availability of 5-FU for anabolism. It is now clear that DPD also accounts for much of the variability observed with the therapeutic use of 5-FU, including variable drug levels during 24-hour infusion, erratic pharmacokinetics, variable bioavaialability, inconsistent toxicity, and variability in drug response (resistance). The use of DPD inhibitors has been explored as a means to improve 5-FU pharmacology. This article describes how drugs that modulate DPD activity have been used to develop a new class of orally administered fluoropyrimidines, now referred to as DPD-inhibiting fluoropyrimidine (DIF) drugs. The biochemical basis for using four DIF drugs--uracil and tegafur (UFT), ethynyluracil, S-1, and BOF-A2--currently in clinical evaluation in the United States, is hereby reviewed. Early clinical data suggest that these drugs may achieve antitumor efficacy equivalent to that of conventional intravenously administered 5-FU therapy, with the additional advantages of reduced toxicity, less expense, and improved quality of life.

cAMP oscillations, generated by adenylyl cyclase A (ACA), coordinate cell aggregation in Dictyostelium and have also been implicated in organizer function during multicellular development. We used a gene fusion of the ACA promoter with a labile lacZ derivative to study the expression pattern of ACA. During aggregation, most cells expressed ACA, but thereafter expression was lost in all cells except those of the anterior tip. Before aggregation, ACA transcription was strongly upregulated by nanomolar cAMP pulses. Postaggregative transcription was sustained by nanomolar cAMP pulses, but downregulated by a continuous micromolar cAMP stimulus and by the stalk-cell-inducing factor DIF. Earlier work showed that the transcription factor StatA displays tip-specific nuclear translocation and directs tip-specific expression of the nuclear protein CudA, which is essential for culmination. Both StatA and CudA were present in nuclei throughout the entire slug in an aca null mutant that expresses ACA from the constitutive actin15 promoter. This suggests that the tip-specific expression of ACA directs tip-specific nuclear translocation of StatA and tip-specific expression of CudA.

Insects possess an antimicrobial defense response that is similar to the mammalian innate immune response. The innate immune system is designed to recognize conserved components of microorganisms called pathogen-associated molecular patterns (PAMPs). How host receptors detect PAMPs and transmit the signals to mount the immune response is being elucidated. Using GFP-Dorsal, -Dif, and -Relish reporter proteins in ex vivo assays, we demonstrate that Drosophila fat bodies, a major immune tissue, have both hemolymph-dependent and -independent responses. Microbial preparations such as lipoteichoic acid (LTA) and peptidoglycan (PGN) can stimulate some responses from dissected and rinsed larval fat bodies. Therefore, at least some aspects of recognition can occur on fat body cell surfaces, bypassing the requirement of hemolymph. Our results also show that supernatants from bacterial cultures can stimulate the nuclear translocation of Dorsal in dissected fat bodies, but this stimulation is strictly hemolymph-dependent. Various biochemical assays suggest that the factors from bacterial supernatants that stimulate the hemolymph-dependent nuclear translocation are likely made up of proteins. We further show that Dorsal mutant larvae have much lower phenoloxidase activity, consistent with a more important role of Dorsal in innate immunity than previously shown.