219 A SOLITARY AWARENESS - PROFILING TIME TO RECOGNITION OF MEMORY LOSS IN A TERTIARY MEMORY SERVICE

Background

Approximately 64,000 people live with dementia in Ireland with expected increases to 150,000 by 2045. Best practice recommends that patients benefit from timely diagnosis. Whilst the presence of cognitive impairment should prompt early referral for diagnostic clarity, patients frequently present with well-established symptoms. In order to understand this phenomenon it is important to understand the way in which symptoms are recognised by the person, companions and casual observers.

Methods

A chart review was carried out on a convenience sample of patients (n=61) diagnosed with dementia where scores were available from Clinical Dementia Rating Scale (CDR) and AD8. Data extracted included global scores and answers to direct questions regarding symptom recognition by patient and companion. Diagnosis was confirmed using the Electronic Patient Record.

Results

Mean age was 75 (range 57-87). Diagnostic breakdown comprised: Alzheimer Dementia (AD) in 67% (n=41), mixed AD/Vascular Dementia (VaD) in 19.6% (n=12); behavioural variant Fronterotemporal Dementia (bvFTD) in 1.6% (n=1), Dementia with Lewey Bodies (DLB) in 1.6% (n=1), Primary Progressive Aphasia (PPA) in 4.9% (n=3), Primary Parkinson’s Dementia (PPD) in 1.6% (n=1) and VaD in 1.6% (n=1). Average CDR Global Scale was 1.0 and average AD8 score 6/8. Family noticed symptoms of dementia an average of 12 months longer than the person themself. The incidence of anosognosia was 19% (n=12) and associated with a diagnosis of AD (91.6 %, n=11). Where anosognosia existed, symptoms of memory loss had been identified by family up to 60 months before diagnosis, with average time to recognition of 24 months. For 75% of this anosognosia group, family reported indiscernible symptoms on casual inspection (n=9).

Conclusion

Where symptoms of memory loss go unrecognised by patients and casual inspection, family may notice changes for up to five years. It is important to educate and empower the public regarding the benefit of a timely dementia diagnosis. Education should focus on supporting family to navigate sensitive conversations in the event of anosognosia and explore ways in which they might encourage timely review.

99 ASSESSMENT AND MANAGEMENT OF PAIN IN OLDER ADULTS WITH ACUTE FRACTURE ADMITTED UNDER AN ORTHOPAEDIC SERVICE

Background

Older adults with acute fractures often have suboptimal pain control, in particular those with cognitive impairment. Effective pain management improves rehabilitation engagement and earlier discharge from acute care. Our study aimed to evaluate pain management of older adults with acute fracture admitted under an orthopaedic service in a tertiary hospital.

Methods

Prospective review of patients over 65 years with an acute fracture admitted under an orthopaedic service. Review of chart, medication prescription and pain status. Data included type of fracture, comorbidities, cognitive status and analgesia prescribed. Data analysed using Excel.

Results

40 inpatients included. Median age 82 years (range 65-93 years), 70% female. 53% had cognitive impairment, ranging from mild to severe dementia. 75% had >5 regular medications pre-admission. 80% had >5 comorbidities.

Two-thirds (73%) had an acute hip fracture. Most (80%) inpatients had a surgical intervention, the remaining were managed conservatively.

Analgesia prescriptions included paracetamol for almost all patients (95%), non-steroidal anti-inflammatory drugs for 3 (8%) and regular opioids in only 3 (8%).

43% of patients reported pain at time of data collection. 13% had analgesia changed in the 24 hours beforehand. Pain adversely affected function in 205 and mobility in 28%.

2 patients were unable to verbalise pain however no pain scales or visual assessments were used.

Documentation of pain assessment was best by nurses (100%) followed by doctors (60%) and allied health professionals (40%).

Conclusion

Older adults with acute fracture are often multimorbid with cognitive impairment. This patient population are often untreated for pain with suboptimal pain assessment and analgesia review or prescriptions. Consequently we developed a pain policy for use on our orthopaedic service as a guide for effective pain assessment and management for older adults with acute fracture.

The Link between Regional Tidal Stretch and Lung Injury during Mechanical Ventilation

The aim of this study was to assess the association between regional tidal volume (Vt), regional functional residual capacity (FRC), and the expression of genes linked with ventilator-induced lung injury. Two groups of BALB/c mice (n = 8 per group) were ventilated for 2 hours using a protective or injurious ventilation strategy, with free-breathing mice used as control animals. Regional Vt and FRC of the ventilated mice was determined by analysis of high-resolution four-dimensional computed tomographic images taken at baseline and after 2 hours of ventilation and corrected for the volume of the region (i.e., specific [s]Vt and specific [s]FRC). RNA concentrations of 21 genes in 10 different lung regions were quantified using a quantitative PCR array. sFRC at baseline varied regionally, independent of ventilation strategy, whereas sVt varied regionally depending on ventilation strategy. The expression of IL-6 (P = 0.04), Ccl2 (P < 0.01), and Ang-2 (P < 0.05) was associated with sVt but not sFRC. The expression of seven other genes varied regionally (IL-1β and RAGE [receptor for advanced glycation end products]) or depended on ventilation strategy (Nfe2l2 [nuclear factor erythroid-derived 2 factor 2], c-fos, and Wnt1) or both (TNF-α and Cxcl2), but it was not associated with regional sFRC or sVt. These observations suggest that regional inflammatory responses to mechanical ventilation are driven primarily by tidal stretch.

Clinical pregnancy from a vitrified/warmed human blastocyst

The first pregnancy after vitrification of a human blastocyst (day 5 of embryo culture) was reported by Yokota et al. in 2000. Since then more attention has been given to the technique of vitrification and its safe application in ART. To the best of our knowledge, this is the first report of a clinical pregnancy resulting in a live birth from the transfer of a vitrified/ warmed human blastocyst in the Republic of Ireland.

The origin of cyanobacteria in Antarctic sea ice: marine or freshwater?

Cyanobacteria play an important role in the primary productivity of many ecosystems and are dominant in non-marine polar environments. Apart from detecting low levels of cyanobacteria-like pigments in the Southern Ocean, little effort has been spent in trying to elucidate Cyanobacteria in Antarctic sea ice. Here, we report the first use of culture, microscope, microarray and molecular techniques to show that marine Cyanobacteria are rare or absent in sea ice. Our infrequent positive signals were most closely related to freshwater Cyanobacteria from neighbouring terrestrial sources, which illustrates our techniques were sensitive enough to find sea-ice cyanobacteria if they were present. It is still possible that minute quantity of marine cyanobacteria may exist in sea ice and do not contribute significantly to the polar marine ecosystems.

Comparative bioactivation of the novel anti-tuberculosis agent PA-824 in Mycobacteria and a subcellular fraction of human liver

BACKGROUND AND PURPOSE

PA-824 is a 2-nitroimidazooxazine prodrug currently in Phase II clinical trial for tuberculosis therapy. It is bioactivated by a deazaflavin (F(420) )-dependent nitroreductase (Ddn) isolated from Mycobacterium tuberculosis to form a des-nitro metabolite. This releases toxic reactive nitrogen species which may be responsible for its anti-mycobacterial activity. There are no published reports of mammalian enzymes bioactivating this prodrug. We have investigated the metabolism of PA-824 following incubation with a subcellular fraction of human liver, in comparison with purified Ddn, M. tuberculosis and Mycobacterium smegmatis.

EXPERIMENTAL APPROACH

PA-824 (250 µM) was incubated with the 9000 × g supernatant (S9) of human liver homogenates, purified Ddn, M. tuberculosis and M. smegmatis for metabolite identification by liquid chromatography mass spectrometry analysis.

KEY RESULTS

PA-824 was metabolized to seven products by Ddn and M. tuberculosis, with the major metabolite being the des-nitro product. Six of these products, but not the des-nitro metabolite, were also detected in M. smegmatis. In contrast, only four of these metabolites were observed in human liver S9; M3, a reduction product previously proposed as an intermediate in the Ddn-catalyzed des-nitrification and radiolytic reduction of PA-824; two unidentified metabolites, M1 and M4, which were products of M3; and a haem-catalyzed product of imidazole ring hydration (M2).

CONCLUSIONS AND IMPLICATIONS

PA-824 was metabolized by des-nitrification in Ddn and M. tuberculosis, but this does not occur in human liver S9 and M. smegmatis. Thus, PA-824 was selectively bioactivated in M. tuberculosis and there was no evidence for 'cross-activation' by human enzymes.

Targeting the chromosome partitioning protein ParA in tuberculosis drug discovery

OBJECTIVE

To identify inhibitors of the essential chromosome partitioning protein ParA that are active against Mycobacterium tuberculosis.

METHODS

Antisense expression of the parA orthologue MSMEG_6939 was induced on the Mycobacterium smegmatis background. Screening of synthetic chemical libraries was performed to identify compounds with higher anti-mycobacterial activity in the presence of parA antisense. Differentially active compounds were validated for specific inhibition of purified ParA protein from M. tuberculosis (Rv3918c). ParA inhibitors were then characterized for their activity towards M. tuberculosis in vitro.

RESULTS

Under a number of culture conditions, parA antisense expression in M. smegmatis resulted in reduced growth. This effect on growth provided a basis for the detection of compounds that increased susceptibility to expression of parA antisense. Two compounds identified from library screening, phenoxybenzamine and octoclothepin, also inhibited the in vitro ATPase activity of ParA from M. tuberculosis. Structural in silico analyses predict that phenoxybenzamine and octoclothepin undergo interactions compatible with the active site of ParA. Octoclothepin exhibited significant bacteriostatic activity towards M. tuberculosis.

CONCLUSIONS

Our data support the use of whole-cell differential antisense screens for the discovery of inhibitors of specific anti-tubercular drug targets. Using this approach, we have identified an inhibitor of purified ParA and whole cells of M. tuberculosis.

Evaluation of the Mycobacterium smegmatis and BCG models for the discovery of Mycobacterium tuberculosis inhibitors

The objective of this study was to measure the efficacy of Mycobacterium smegmatis as a surrogate in vitro model for the detection of compounds which are inhibitory to the growth of Mycobacterium tuberculosis. A chemical screen of the LOPAC library for anti-mycobacterial compounds was performed using M. smegmatis. Parallel screens were conducted with another tuberculosis model, Mycobacterium bovis BCG, and with M. tuberculosis under identical growth conditions and the inhibitors detected across the three species were compared. 50% of compounds that were detected as active against M. tuberculosis were not detected using M. smegmatis compared to 21% of compounds using M. bovis BCG. To examine whether these findings were unique to LOPAC, screens were performed with the NIH Diversity Set and Spectrum Collection. An even higher proportion of M. tuberculosis inhibitors were not detected from the NIH Diversity Set and Spectrum Collection using M. smegmatis compared to M. bovis BCG. These data reveal that a significant proportion of M. tuberculosis inhibitors are missed in library screening with M. smegmatis. The basis of the variation in the inhibitory profiles of M. smegmatis and M. tuberculosis has yet to be fully determined, however, our genomic comparisons indicate that approximately 30% of M. tuberculosis proteins lack conserved orthologues in M. smegmatis compared to 3% being absent in M. bovis BCG. In conclusion, although M. smegmatis offers some technical benefits such as a shorter generation time and negligible risk to laboratory workers, it is significantly less effective in the detection of anti-M. tuberculosis compounds relative to M. bovis BCG. This limitation needs to be taken into consideration when selecting an in vitro screening model for tuberculosis drug discovery.

Native New Zealand plants with inhibitory activity towards Mycobacterium tuberculosis

Background

Plants have long been investigated as a source of antibiotics and other bioactives for the treatment of human disease. New Zealand contains a diverse and unique flora, however, few of its endemic plants have been used to treat tuberculosis. One plant, Laurelia novae-zelandiae, was reportedly used by indigenous Maori for the treatment of tubercular lesions.

Methods

Laurelia novae-zelandiae and 44 other native plants were tested for direct anti-bacterial activity. Plants were extracted with different solvents and extracts screened for inhibition of the surrogate species, Mycobacterium smegmatis. Active plant samples were then tested for bacteriostatic activity towards M. tuberculosis and other clinically-important species.

Results

Extracts of six native plants were active against M. smegmatis. Many of these were also inhibitory towards M. tuberculosis including Laurelia novae-zelandiae (Pukatea). M. excelsa (Pohutukawa) was the only plant extract tested that was active against Staphylococcus aureus.

Conclusions

Our data provide support for the traditional use of Pukatea in treating tuberculosis. In addition, our analyses indicate that other native plant species possess antibiotic activity.

Expression of zebrafish cxcl8 (interleukin-8) and its receptors during development and in response to immune stimulation

Cxcl8 is a pro-inflammatory chemokine, best known for its role in neutrophil chemotaxis. Signalling through its receptors, Cxcr1 and Cxcr2, is induced by inflammatory stimuli evoked by microbial, chemical or environmental stress, and hormonal signals. While it is recognised that Cxcl8 signalling is active in the gut mucosa, this is not as well understood as its role in leukocyte trafficking. Here, we report the characterisation of genes encoding the zebrafish Cxcl8, Cxcr1 and Cxcr2. By a combination of genomic, expression and functional analyses, we show that the Cxcl8 signalling pathway is conserved in zebrafish. As in humans, cxcl8 is expressed in zebrafish leukocytes. Transcripts were also detected in intestinal epithelial cells, and this expression is upregulated under inflammatory conditions caused by bacterial or chemical insult. Expression of cxcr1 and cxcr2 is robust within the developing gut. This work provides a model for the study of Cxcl8 signalling during gut inflammation.

Experimental models used to study human tuberculosis

Mycobacterium tuberculosis causes more deaths in humans than any other bacterial pathogen. The most recent data from the World Health Organization reveal that over 9million new cases of tuberculosis occur each year and that the incidence appears to be increasing with population growth. Despite the global burden of tuberculosis, we are still reliant on relatively dated measures to prevent, diagnose, and treat the disease. New, more effective tools are needed to diminish the incidence of tuberculosis. M. tuberculosis lacks a natural host beyond humans and, hence, surrogate models have been employed in the study of the pathogen. The discovery and development of new vaccines, diagnostics, or antitubercular drugs are dependent upon the validity of any experimental model used and its relevance to tuberculosis in humans. In this review, a range of experimental models, from in vitro studies with fast-growing low-pathogenic species of mycobacteria to the infection of nonhuman primates with virulent M. tuberculosis, will be discussed.

Subcuticular bacteria associated with two common New Zealand echinoderms: Characterization using 16S rRNA sequence analysis and fluorescence in situ hybridization

Many echinoderms contain subcuticular bacteria (SCB), symbionts which reside in the lumen between the host's epidermal cells and outer cuticle. This relationship is common, existing in about 60% of echinoderms studied so far, yet the function of SCB remains largely unknown. In this study, phylogenetic analysis was carried out on 16S rRNA sequences obtained from echinoderm-associated bacteria, resulting in the identification of four species of putative SCB. All four bacteria were identified from the holothurian Stichopus mollis, and two of the four were also found in the asteroid Patiriella sp. Two of these bacteria belong to the Alphaproteobacteria, and two to the Gammaproteobacteria. In addition to phylogenetic analysis, fluorescence in situ hybridization (FISH) assays were carried out on Patiriella sp., S. mollis, and the asteroid Astrostole scabra. Results showed that Patiriella sp. and S. mollis contain SCB, in agreement with the phylogenetic analysis, while SCB were not detected in A. scabra. Of the bacteria detected using FISH, more than 80% were recognized as belonging to the Alphaproteobacteria in both host species. However, in S. mollis about 20% of the detected SCB successfully hybridized with the Gammaproteobacteria-specific probe, whereas bacteria belonging to this class were never observed in Patiriella sp. This is only the second study to characterize SCB by molecular means, and is the first to identify SCB in situ using FISH.

Multidisciplinary approach for patients with pelvic fractures and hemodynamic instability

The hemodynamically unstable patient with a pelvic fracture presents a diagnostic and therapeutic challenge. The care of these patients requires a unique multidisciplinary approach with input and expertise from many different specialists. An understanding of pelvic anatomy and fracture patterns can help guide the diagnostic evaluation and treatment plan. The initial management of these patients must focus on rapid airway and hemorrhage control while preparing for ongoing blood loss. Rapid temporary fracture stabilization with simple bedside modalities is crucial in limiting additional blood loss. An exhaustive search must also be performed to evaluate for concomitant injuries that commonly accompany major pelvic fractures and the treatment of these other injuries must be appropriately prioritized. For patients who are unresponsive to standard resuscitation and bedside attempts at limiting hemorrhage, angiographic embolization is often utilized as the next step to attain hemodynamic stability. The key to successful management of these patients lies in the careful coordination of different specialists and the expertise that each brings to the clinical care of the patient.

Investigation of the physiological relationship between the cyanide-insensitive oxidase and cyanide production in Pseudomonas aeruginosa

Pseudomonas aeruginosa is an opportunistic pathogen which demonstrates considerable respiratory versatility, possessing up to five terminal oxidases. One oxidase, the cyanide-insensitive oxidase (CIO), has been previously shown to be resistant to the potent respiratory inhibitor cyanide, a toxin that is synthesized by this bacterium. This study investigated the physiological relationship between hydrogen cyanide production and the CIO. It was found that cyanide is produced in P. aeruginosa at similar levels irrespective of its complement of CIO, indicating that the CIO is not an obligatory electron sink for cyanide synthesis. However, MICs for cyanide and growth in its presence demonstrated that the CIO provides P. aeruginosa with protection against the effects of exogenous cyanide. Nevertheless, the presence of cyanide did not affect the viability of cio mutant strains compared to the wild-type during prolonged incubation in stationary phase. The detection of the fermentation end products acetate and succinate in stationary-phase culture supernatants suggests that P. aeruginosa, irrespective of its CIO complement, may in part rely upon fermentation for energy generation in stationary phase. Furthermore, the decrease in cyanide levels during incubation in sealed flasks suggested that active breakdown of HCN by the culture was taking place. To investigate the possibility that the CIO may play a role in pathogenicity, wild-type and cio mutant strains were tested in the paralytic killing model of Caenorhabditis elegans, a model in which cyanide is the principal toxic agent leading to nematode death. The CIO mutant had delayed killing kinetics, demonstrating that the CIO is required for full pathogenicity of P. aeruginosa in this animal model.

Contrasting signal transduction mechanisms in bacterial and eukaryotic gene transcription

All known cell types use signal transduction systems to respond to an extracellular or intracellular event. The role of these systems can be to adapt to environmental changes or simply to maintain homeostasis. Cells detect and respond to stimuli in a number of ways. Here we review the mechanisms involved in the transmission of a signal from point of detection to site of action. In particular, a comparison is made between the signalling networks which function in gene transcription in bacterial and eukaryotic cells. Knowledge of the similarities between the systems found in the two types of cells can provide a better understanding of the function and origin of signalling components. In addition, the divergence evident can be exploited by molecules that modulate or disrupt the function of differential signalling mechanisms.

Tetracycline-inducible gene regulation in mycobacteria

A system for the tetracycline-inducible regulation of gene expression in mycobacteria has been developed. We have sub-cloned the tetRO region from the Corynebacterium glutamicum TetZ locus into a mycobacterial shuttle plasmid, making expression of genes cloned downstream of tetRO responsive to tetracycline. Using the luxAB-encoded luciferase from Vibrio harveyi as a reporter (pMind-Lx), we observed a 40-fold increase in light output from Mycobacterium smegmatis cultures 2 h after adding 20 ng ml⁻¹ of tetracycline. Similarly, exposure to the drug resulted in up to 20-fold increase in relative light units from M.bovis BCG carrying the reporter construct, and a 10-fold increase for M.tuberculosis. Tetracycline induction was demonstrated in log and stationary phase cultures. To evaluate whether this system is amenable to use in vivo, J774 macrophages were infected with M.bovis BCG[pMind-Lx], treated with amikacin to kill extracellular bacteria, and then incubated with tetracycline. A 10-fold increase in light output was measured after 24 h, indicating that intracellular bacteria are accessible and responsive to exogenously added tetracycline. To test the use of the tetracycline-inducible system for conditional gene silencing, mycobacteria were transformed with a pMind construct with tetRO driving expression of antisense RNA for the ftsZ gene. Bacterial cells containing the antisense construct formed filaments after 24 h exposure to tetracycline. These results demonstrate the potential of this tetracycline-regulated system for the manipulation of mycobacterial gene expression inside and outside cells.

Visualisation of Zebrafish infection by GFP-labelled Vibrio anguillarum

Vibrio anguillarum is an invasive pathogen of fish causing a septicaemia called vibriosis. In this work, transparent zebrafish were immersed in water containing green fluorescent protein labelled V. anguillarum. The infection was visualised at the whole fish and single bacterium levels using microscopy. The gastrointestinal tract was the first site where the pathogen was detected. This enteric localisation occurred independently of the flagellum or motility. On the other hand, chemotactic motility was essential for association of the pathogen with the fish surface. In conclusion, the zebrafish infection model provides evidence that the intestine and skin represent sites of infection by V. anguillarum and suggests a host site where chemotaxis may function in virulence.

Development and application of unstable GFP variants to kinetic studies of mycobacterial gene expression

Unstable variants of green fluorescent protein (GFP) tagged with C-terminal extensions, which are targets for a tail specific protease, have been described in Escherichia coli and Pseudomonas putida [Appl. Envir. Microbiol. 64 (1998) 2240]. We investigated whether similar modifications to flow cytometer optimised GFP (GFPmut2) could be used to generate unstable variants of GFP for gene expression studies in mycobacteria. We constructed GFP variants in a mycobacterial shuttle vector under the control of the regulatory region of the inducible Mycobacterium smegmatis acetamidase gene. GFP expression was induced by the addition of acetamide and the stability of the GFP variants in M. smegmatis, following the removal of the inducer to switch off their expression, was determined using spectrofluorometry and flow cytometry. We demonstrate that, compared to the GFPmut2 (half-lives>7 days), the modified GFP variants exhibit much lower half-lives (between 70 and 165 min) in M. smegmatis. To investigate their utility in the measurement of mycobacterial gene expression, we cloned the promoter region of a putative amino acid efflux pump gene, lysE (Rv1986), from Mycobacterium tuberculosis together with the divergently transcribed, putative lysR-type regulator gene (Rv1985c) upstream of one of the unstable GFP variants. We found that the expression kinetics of the lysRE-gfp fusion were identical throughout the M. smegmatis growth curve to those measured using a conventional lysRE-xylE reporter fusion, peaking upon entry into stationary phase. In addition, it was established that the tagged GFP variants were also unstable in Mycobacterium bovis BCG. Thus, we have demonstrated that unstable GFP variants are suitable reporter genes for monitoring transient gene expression in fast- and slow-growing mycobacteria.

Universal stress proteins and Mycobacterium tuberculosis

Mycobacterium tuberculosis expresses universal stress proteins (USPs) when its growth is retarded by oxygen depletion. This class of proteins is emerging as being important in the resistance of bacteria to stress and prolonged growth arrest. Here we assess the properties of USPs and their relevance to mycobacteria.

A two-component regulator of universal stress protein expression and adaptation to oxygen starvation in Mycobacterium smegmatis

We identified a response regulator in Mycobacterium smegmatis which plays an important role in adaptation to oxygen-starved stationary phase. The regulator exhibits strong sequence similarity to DevR/Rv3133c of M. tuberculosis. The structural gene is present on a multigene locus, which also encodes a sensor kinase. A devR mutant of M. smegmatis was adept at surviving growth arrest initiated by either carbon or nitrogen starvation. However, its culturability decreased several orders of magnitude below that of the wild type under oxygen-starved stationary-phase conditions. Two-dimensional gel analysis revealed that a number of oxygen starvation-inducible proteins were not expressed in the devR mutant. Three of these proteins are universal stress proteins, one of which is encoded directly upstream of devR. Another protein closely resembles a proposed nitroreductase, while a fifth protein corresponds to the alpha-crystallin (HspX) orthologue of M. smegmatis. None of the three universal stress proteins or nitroreductase, and a considerably lower amount of HspX was detected in carbon-starved wild-type cultures. A fusion of the hspX promoter to gfp demonstrated that DevR directs gene expression when M. smegmatis enters stationary phase brought about, in particular, by oxygen starvation. To our knowledge, this is the first time a role for a two-component response regulator in the control of universal stress protein expression has been shown. Notably, the devR mutant was 10(4)-fold more sensitive than wild type to heat stress. We conclude that DevR is a stationary-phase regulator required for adaptation to oxygen starvation and resistance to heat stress in M. smegmatis.

Role of motility in adherence to and invasion of a fish cell line by Vibrio anguillarum

To understand further the role of the flagellum of Vibrio anguillarum in virulence, invasive and adhesive properties of isogenic motility mutants were analyzed by using a chinook salmon embryo cell line. Adhesion was unaffected but invasion of the cell line was significantly decreased in nonmotile or partially motile mutants, and the chemotactic mutant was hyperinvasive. These results suggest that active motility aids invasion by V. anguillarum, both in vivo and in vitro.

Teachers' recognition and reporting of child abuse: a factorial survey

OBJECTIVE

The major aim of this study was to determine the effect of characteristics of the case, the teacher, and the organizational setting on recognition and reporting of child abuse.

METHOD

A factorial survey design was employed in which a probability sample of teachers (N = 480) responded to vignettes in which case characteristics were systematically manipulated.

RESULTS

Analysis using OLS regression showed that case characteristics alone accounted for 50.30% of the variance in recognition and 51.08% of the variance in reporting: the strongest effects were from type and seriousness of abuse, positive behavior of the victim and positive psychology of the perpetrator. The inclusion of variables describing the teachers and the school explained only a very small additional proportion of the variance in teacher's responses.

CONCLUSIONS

Teachers responses to child abuse are relatively unbiased by either the extraneous characteristics of the perpetrator or victim, the responding teacher, or the school setting. The findings do not appear to support the problem of "overreporting." There is evidence for "underreporting," particularly in less serious cases involving physical and emotional abuse. Teachers are undeterred by the many problems and fears that may accompany a report of child abuse to Child Protective Services. Teachers use discretion in reporting abuse they recognize.

The chemotactic response of Vibrio anguillarum to fish intestinal mucus is mediated by a combination of multiple mucus components

Chemotactic motility has previously been shown to be essential for the virulence of Vibrio anguillarum in waterborne infections of fish. To investigate the mechanisms by which chemotaxis may function during infection, mucus was isolated from the intestinal and skin epithelial surfaces of rainbow trout. Chemotaxis assays revealed that V. anguillarum swims towards both types of mucus, with a higher chemotactic response being observed for intestinal mucus. Work was performed to examine the basis, in terms of mucus composition, of this chemotactic response. Intestinal mucus was analyzed by using chromatographic and mass spectrometric techniques, and the compounds identified were tested in a chemotaxis assay to determine the attractants present. A number of mucus-associated components, in particular, amino acids and carbohydrates, acted as chemoattractants for V. anguillarum. Importantly, only upon combination of these attractants into a single mixture were levels of chemotactic activity similar to those of intestinal mucus generated. A comparative analysis of skin mucus revealed its free amino acid and carbohydrate content to be considerably lower than that of the more chemotactically active intestinal mucus. To study whether host specificity exists in relation to vibrio chemotaxis towards mucus, comparisons with a human Vibrio pathogen were made. A cheR mutant of a Vibrio cholerae El Tor strain was constructed, and it was found that V. cholerae and V. anguillarum exhibit a chemotactic response to mucus from several animal sources in addition to that from the human jejunum and fish epithelium, respectively.

RpoN of the fish pathogen Vibrio (Listonella) anguillarum is essential for flagellum production and virulence by the water-borne but not intraperitoneal route of inoculation

To investigate the involvement of RpoN in flagellum production and pathogenicity of Vibrio (Listonella) anguillarum, the rpoN gene was cloned and sequenced. The deduced product of the rpoN gene displayed strong homology to the alternative sigma 54 factor (RpoN) of numerous species of bacteria. In addition, partial sequencing of rpoN-linked ORFs revealed a marked resemblance to similarly located ORFs in other bacterial species. A polar insertion or an in-frame deletion in the coding region of rpoN abolished expression of the flagellin subunits and resulted in loss of motility. Introduction of the rpoN gene of V. anguillarum or Pseudomonas putida into the rpoN mutants restored flagellation and motility. The rpoN mutants were proficient in the expression of other proposed virulence determinants of V. anguillarum, such as ability to grow under low available iron conditions, and expression of the LPS O-antigen and of haemolytic and proteolytic extracellular products. The infectivity of the rpoN mutants with respect to the wild-type strain was unaffected following intraperitoneal injection of fish but was reduced significantly when fish were immersed in bacteria-containing water. Thus, RpoN does not appear to regulate any factors required for virulence subsequent to penetration of the fish epithelium, but is important in the infection of fish by water-borne V. anguillarum.

Intraperitoneal cisplatin plus intravenous cyclophosphamide versus intravenous cisplatin plus intravenous cyclophosphamide for stage III ovarian cancer

BACKGROUND

Intravenous platinum-based chemotherapy is the standard primary therapy for advanced ovarian cancer. We conducted a phase 3 trial to compare the effects of intraperitoneal and intravenous cisplatin on the survival of women with previously untreated, stage III, epithelial ovarian cancer.

METHODS

The patients underwent an initial exploratory laparotomy and resection of all tumor masses larger than 2 cm. Within four weeks after surgery, six courses of intravenous cyclophosphamide (600 mg per square meter of body-surface area per course) plus either intraperitoneal cisplatin (100 mg per square meter) or intravenous cisplatin (100 mg per square meter) were administered at three-week intervals.

RESULTS

Of 654 randomized patients, 546 were eligible for the study. The estimated median survival was significantly longer in the group receiving intraperitoneal cisplatin (49 months; 95 percent confidence interval, 42 to 56) than in the group receiving intravenous cisplatin (41 months; 95 percent confidence interval, 34 to 47). The risk of death was lower in the intraperitoneal group than in the intravenous group (hazard ratio, 0.76; 95 percent confidence interval, 0.61 to 0.96; P = 0.02). Moderate-to-severe tinnitus, clinical hearing loss, and neuromuscular toxic effects were significantly more frequent in the intravenous group.

CONCLUSIONS

As compared with intravenous cisplatin, intraperitoneal cisplatin significantly improves survival and has significantly fewer toxic effects in patients with stage III ovarian cancer and residual tumor masses of 2 cm or less.

Nurses' diagnostic work on possible physical child abuse

The concept of diagnostic work (A. Strauss, S. Fagerhaugh, B. Suczek, & C. Wiener, 1985) is used to explore nurses' responses to potential child abuse. A total of 1,036 nurses (response rate of 67%) completed a mailed questionnaire that included open-ended qualitative-type questions about a hypothetical situation involving possible child abuse. We report their judgments regarding information presented in the hypothetical situation and additional information they requested to make the diagnosis. Nurses focused primarily on the child's injuries and behavior and wanted more information about the abuse event. Diagnostic work was then analyzed by specialty group: community health, school health, emergency, and pediatric nursing. Nurses' specialization influenced the choice of information that was determined to be decisive and the additional information desired to make a diagnosis.

Flagellin A is essential for the virulence of Vibrio anguillarum

A flagellin gene from the fish pathogen Vibrio anguillarum was cloned, sequenced, and mutagenized. The DNA sequence suggests that the flaA gene encodes a 40.1-kDa protein and is a single transcriptional unit. A polar mutation and four in-frame deletion mutations (180 bp deleted from the 5' end of the gene, 153 bp deleted from the 3' end of the gene, a double deletion of both the 180- and 153-bp deletions, and 942 bp deleted from the entire gene) were made. Compared with the wild type, all mutants were partially motile, and a shortening of the flagellum was seen by electron microscopy. Wild-type phenotypes were regained when the mutations were transcomplemented with the flaA gene. Protein analysis indicated that the flaA gene corresponds to a 40-kDa protein and that the flagellum consists of three additional flagellin proteins with molecular masses of 41, 42, and 45 kDa. N-terminal sequence analysis confirmed that the additional proteins were flagellins with N termini that are 82 to 88% identical to the N terminus of FlaA. Virulence studies showed that the N terminal deletion, the double deletion, and the 942-bp deletion increased the 50% lethal dose between 70- and 700-fold via immersion infection, whereas infection via intraperitoneal injection showed no loss in virulence. In contrast, the polar mutant and the carboxy-terminal deletion mutant showed approximately a 10(4)-fold increase in the 50% lethal dose by both immersion and intraperitoneal infection. In summary, FlaA is needed for crossing the fish integument and may play a role in virulence after invasion of the host.

Chemotactic motility is required for invasion of the host by the fish pathogen Vibrio anguillarum

The role of the flagellum and motility in the virulence of the marine fish pathogen Vibrio anguillarum was examined. Non-motile mutants were generated by transposon mutagenesis. Infectivity studies revealed that disruption of the flagellum and subsequent loss of motility correlated with an approximate 500-fold decrease in virulence when fish were inoculated by immersion in bacteria-containing water. However, the flagellar filament and motility were not required for pathogenicity following intraperitoneal injection of fish. The transposon-insertion site for six mutants was determined by cloning and sequencing of the Vibrio DNA flanking the transposon. V. anguillarum genes whose products showed strong homology to proteins with an established role in flagellum biosynthesis were identified. One of the aflagellate mutants had a transposon insertion in the rpoN gene of V. anguillarum. This rpoN mutant failed to grow at low concentrations of available iron and was avirulent by both the immersion and intraperitoneal modes of inoculation. A chemotaxis gene, cheR, was located upstream of one transposon insertion and an in-frame deletion was constructed in the coding region of this gene. The resulting non-chemotactic mutant exhibited wild-type pathogenicity when injected intra-peritoneally into fish but showed a decrease in virulence similar to that seen for the non-motile aflagellate mutants following immersion infection. Hence, chemotactic motility is a required function of the flagellum for the virulence of V. anguillarum.

Phase II trial of amonafide in patients with advanced metastatic or recurrent endometrial adenocarcinoma. A Southwest Oncology Group study

Amonafide, a benzisoquinoline-1,3-dione was administered to 38 patients with recurrent or metastatic, bidimensionally measurable endometrial cancer. There were 34 patients with no prior cytotoxic chemotherapy, performance status of 0-2, and normal bone marrow, renal, and hepatic function were eligible for response and toxicity evaluation. Amonafide, 300 mg/m2, was administered intravenously over 1 hour daily for 5 consecutive days. Courses were repeated every 21 days. The major grade 3 or 4 toxicities were hematologic with granulocytopenia in 18 patients (53%), thrombocytopenia in 6 patients (18%), and anemia in 8 patients (24%). Infectious complications occurred in 3 patients (9%). Other side effects included cardiac dysrhythmias, hypotension, pain and phlebitis at the site of injection, nausea, vomiting, and flu-like symptoms. The overall objective response rate was 6% (95% confidence interval of 1-20%); 2 patients had a complete response (6%), 9 patients had stable disease (26%) and 21 patients had progressive disease (62%). Two patients had insufficient follow-up for response determination and are assumed to be nonresponders. The median survival of the eligible patients was 8 months. With the toxicity observed and the low response rate, amonafide at this dose and schedule has no efficacy in the treatment of endometrial cancer.

Results of a Southwest Oncology Group phase III trial of carboplatin plus cyclophosphamide versus cisplatin plus cyclophosphamide in advanced ovarian cancer

Cisplatin combined with cyclophosphamide has been considered a very active treatment for advanced ovarian cancer. Unfortunately, cisplatin is associated with dose-limiting neurotoxicity, as well as possible neuropathy, ototoxicity, and occasional renal dysfunction. Carboplatin, a cisplatin analogue, is active against advanced ovarian cancer, with a presumed lower incidence of emesis, ototoxicity, neuropathy, and renal dysfunction. The Southwest Oncology Group initiated a phase III randomized trial, in which 342 patients with stage III (suboptimal disease) and stage IV ovarian cancer were randomly assigned to treatment with six courses of intravenous cisplatin 100 mg/m2 plus cyclophosphamide 600 mg/m2 or carboplatin 300 mg/m2 plus cyclophosphamide 600 mg/m2. The median survival for the cisplatin arm was 17.4 months; for the carboplatin arm, median survival was 20.0 months. The null hypothesis of a 30% survival superiority with the cisplatin arm was rejected at the p = 0.02 level. Clinical response rates were 52% for the cisplatin arm and 61% for the carboplatin arm. There was less thrombocytopenia in the cisplatin arm (p < 0.001); however, there was less nausea and emesis (p < 0.001 for courses one to five), renal toxicity (p < 0.001), anemia (p < 0.001), hearing loss (p < 0.001), and neuromuscular toxicity (p < 0.001) in the carboplatin arm. Carboplatin/cyclophosphamide proved to have a significantly better therapeutic index than cisplatin/cyclophosphamide in these patients with advanced ovarian cancer.

Analysis of patient age as an independent prognostic factor for survival in a phase III study of cisplatin-cyclophosphamide versus carboplatin-cyclophosphamide in stages III (suboptimal) and IV ovarian cancer. A Southwest Oncology Group study

BACKGROUND

The purpose of this study was to evaluate the effect of age (i.e., less than 65 years or 65 years of age and older) on survival in a recently completed phase III Southwest Oncology Group study in ovarian cancer patients.

METHODS

Multivariate and univariate regression analyses were used to identify independent prognostic factors of survival in 342 patients with previously untreated Stage III (suboptimal) or Stage IV ovarian cancer who participated in a randomized, phase III study of intravenous (I.V.) carboplatin 300 mg/m2 plus I.V. cyclophosphamide 600 mg/m2 versus I.V. cisplatin 100 mg/m2 plus I.V. cyclophosphamide 600 mg/m2 every 4 weeks for six courses.

RESULTS

Multivariate regression analysis showed the following variables to be independent prognostic factors of survival: age (P = 0.04); performance status (P = 0.004); disease stage (P = 0.03); and race (P = 0.05). Patients under 65 years of age survived significantly longer than those 65 years or older, especially patients with a performance status of 2. Patients with a baseline performance status of 0-1 survived longer than patients with a performance status of 2, and Stage III patients longer than those with Stage IV disease. An unexpected finding was that white patients survived significantly longer than black patients, regardless of age, performance status, or stage of disease. Carboplatin-cyclophosphamide-treated patients experienced similar survival and significantly less nausea and emesis, renal toxicity, hearing loss, tinnitus, neuromuscular toxicities, and alopecia.

CONCLUSIONS

Ovarian cancer patients with advanced disease who are 65 years of age or older and/or with a performance status of 2 have significantly decreased survival compared to their younger and/or less debilitated counterparts. Carboplatin-cyclophosphamide is the recommended treatment (rather than cisplatin-cyclophosphamide), especially for older or debilitated patients because it is associated with less toxicity and similar survival.

Improved therapeutic index of carboplatin plus cyclophosphamide versus cisplatin plus cyclophosphamide: final report by the Southwest Oncology Group of a phase III randomized trial in stages III and IV ovarian cancer

PURPOSE

To compare cisplatin-cyclophosphamide versus carboplatin-cyclophosphamide as primary chemotherapy for stage III (suboptimal) and stage IV ovarian cancer.

PATIENTS AND METHODS

Three hundred forty-two patients were randomly assigned to treatment with six courses of intravenous (i.v.) cisplatin 100 mg/m2 plus i.v. cyclophosphamide 600 mg/m2, or i.v. carboplatin 300 mg/m2 plus i.v. cyclophosphamide 600 mg/m2.

RESULTS

The estimated median survivals were 17.4 and 20.0 months for the cisplatin and carboplatin study arms, respectively. The null hypothesis of a 30% survival superiority with the cisplatin arm was rejected at the P = .02 level. Clinical response rates were 52% for the cisplatin arm and 61% for the carboplatin arm. Pathologic complete response rates were similar for both study arms. There was less thrombocytopenia on the cisplatin arm (P less than .001); however, there was less nausea and emesis (P less than or equal to .001 for courses 1 to 5), renal toxicity (P less than .001), anemia (P = .01), hearing loss (P less than .001), tinnitus (P = .01), neuromuscular toxicities (P = .001), and alopecia (P less than .001) on the carboplatin arm.

CONCLUSION

Carboplatin-cyclophosphamide proved to have a significantly better therapeutic index than cisplatin-cyclophosphamide in patients with stage III (suboptimal) and stage IV ovarian cancer.