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Pyramidellids are tiny ectoparasitic gastropods with highly derived feeding structures for piercing and sucking. We attempted to resolve homology controversies about unique pyramidellid feeding structures by examining foregut development through larval and metamorphic stages, using sections for light and electron microscopy. We anticipated that, like many marine invertebrate larvae, post-metamorphic structures would differentiate extensively in late larvae to speed metamorphic transition. Previous studies of gastropods suggested that development of juvenile feeding structures in larvae was facilitated by foregut subdivision into dorsal and ventral developmental modules, and spatial uncoupling of these modules may have facilitated adaptive radiation in neogastropods. Observations of Odostomia tenuisculpta suggested that the stylet may be derived from cuticle-secreting buccal epithelium surrounding the proximal end of the salivary duct, whereas the stylet sheath could be either a derived jaw or a radular tooth. The anterior half of the remarkable buccal pump of these euthyneuran gastropods develops from the larval esophagus, which is unorthodox compared to caenogastropods, where extensive post-metamorphic specialization of a dorsal module component has not been previously described. The introvert tube develops from pouches of the distal larval esophagus and may actually be an eversible oral tube rather than an acrembolic proboscis. Minimal differentiation of presumptive juvenile foregut structures occurred during the larval stage of O. tenuisculpta, when compared to other gastropods. The stylet, stylet sheath, and buccal pump may be incompatible with functioning of the larval esophagus; thus, an explosive period of morphogenesis is necessary at metamorphosis. Although dorsal and ventral modules were recognizable during the development of O. tenuisculpta, we failed to find evidence that this modularity facilitated the extreme evolutionary remodeling of post-metamorphic feeding structures.

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Previous studies on bacterial response to antibiotics mainly focused on susceptible strains. Here we characterized the transcriptional responses of distinct cephalosporin-resistant bacteria of public health relevance to cefotaxime (CTX), a cephalosporin widely used in clinical practice. Adaptation to therapeutic concentrations of CTX (30 µg/ml) was investigated by RNA sequencing in mid-exponential phase cultures of a methicillin-resistant Staphylococcus aureus (MRSA) and two genetically diverse E. coli producing CTX-M-15 or CMY-2 ß-lactamase following genome sequencing and annotation for each strain. MRSA showed the most notable adaptive changes in the transcriptome after exposure to CTX, mainly associated with cell envelope functions. This reprogramming coincided with a transient reduction in cell growth, which also occurred in the CMY-2-producing E. coli but not in the CTX-M-15-producing strain. Re-establishment of growth in the CMY-2 producer proceeded without any notable adaptive transcriptional response, while limited reprogramming of gene transcription was observed in the CTX-M-15 producer. Our data show that the transcriptional response of CTX-resistant bacteria to CTX depends on the bacterial species, level of resistance and resistance determinant involved. Gene products induced in the presence of CTX may play an essential role for bacterial survival during therapy and merit further investigation as possible targets for potentiating CTX.

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OBJECTIVE: To determine the clinical effectiveness, cost-effectiveness and service users' views of enhanced early communication therapy by speech and language (SL) therapists compared with attention control (AC). DESIGN: Successful feasibility study followed by a randomised trial with economic evaluation, and nested qualitative study using 32 individual interviews. SETTING: Twelve English NHS hospital and community stroke services. PARTICIPANTS: One hundred and seventy adults with aphasia or dysarthria admitted to hospital with stroke, December 2006 to January 2010. Eligibility determined by NHS SL therapists. Seventeen people declined follow-up. INTERVENTIONS: A best-practice, flexible intervention by NHS SL therapists, up to three contacts per week for up to 16 weeks compared with a similar number of AC contacts by employed visitors. MAIN OUTCOME MEASURES: Primary outcome was blinded, functional communicative ability 6 months post randomisation on the Therapy Outcome Measure activity subscale (TOM). Secondary outcomes were participants' perceptions on the Communication Outcomes After Stroke scale (COAST); carers' perceptions of participants from part of the Carer COAST; carer well-being on Carers of Older People in Europe Index and quality-of-life items from Carer COAST. Serious adverse events (SAEs) were recorded. Economic evaluation: participants' utility (European Quality of Life-5 Dimensions), service use and cost data from medical records and carers, and a discrete choice experiment. RESULTS: Intervention typically started after 2 weeks, providing 22 contacts. Both groups improved on the TOM. The estimated 6 months' group difference [95% confidence interval (CI)] was 0.25 (-0.19 to 0.69) points in favour of SL therapy. Sensitivity analyses adjusting for baseline chance imbalance or not imputing values for decedents further reduced this difference. Per-protocol analyses rejected a possible dilution of therapy from controls refusing allocation and receiving NHS SL therapy. There was no evidence of added benefit of therapy on any secondary outcome measure or SAEs, although the latter were less frequent in the therapy group [odds ratio 0.42 (95% CI 0.16 to 1.1)]. Regardless of group allocation, interviewed participants reported positive impacts on their confidence and mood, identified drivers for change and valued early and sustained contact. Health economic analysis indicated a high level of uncertainty. Early enhanced SL therapy for communication is likely to be cost-effective only if decision-makers are prepared to pay ≥ £25,000 to gain one unit of utility. CONCLUSIONS: These findings exclude the possibility of a clinically significant difference of 0.5 points on the TOM. There was no evidence, on any measure, of added benefit of early communication therapy beyond that from AC. It is unclear whether therapy is more or less cost-effective than AC. Early, frequent contact was highly valued by users and had good uptake. Functional communication improved for both groups, plausibly due to natural recovery and early and regular opportunity to practise everyday communication with a professional (therapist/visitor). There is no evidence to recommend enhancing the provision of early communication therapy by a qualified SL therapist over and above usual care. SL therapy service reorganisation should consider skill mix and timing within a stepped care model and should take place within the context of a trial.

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OBJECTIVE: To develop and validate a clinically feasible measure of communication effectiveness for people with any type of communication problem following stroke. DESIGN: Cross-sectional, interview-based, psychometric study, building on the development phase for construction of the Communication Outcome after Stroke (COAST) scale. SETTING: A community sample from the northwest of England, UK. SUBJECTS: One hundred and two people with communication problems (aphasia and/or dysarthria) following a stroke, within the previous 4-12 months. INTERVENTIONS: Administration of the COAST scale, on two occasions, within a two-week period, and collection of demographic and other data relating to disability, degree of aphasia (where appropriate) and hospital diagnosis of aphasia/dysarthria. MAIN MEASURES: Acceptability (missing values), reliability (internal consistency and test-retest reliability) and item analysis (item redundancy). RESULTS: Ninety-seven (visit 1) and 98 (visit 2) respondents provided usable data for the psychometric analysis. The 29-item COAST scale showed good acceptability (few missing values, sample spread 28-100%), internal consistency and test-retest reliability for the scale (alpha = 0.95; ICC = 0.90) and its subscales (alpha = 0.65-0.93; ICC = 0.72-0.88), but possible item redundancy. A revised scale of 20 items was produced, demonstrating good internal consistency and test-retest reliability (alpha = 0.83-92; ICC = 0.72-0.88). CONCLUSIONS: The COAST is a patient-centred, practical and reliable measure that can be used to assess self-perceived communication effectiveness for people with aphasia and/or dysarthria. Further testing on construct validity and responsiveness to change is needed before the measure can be firmly recommended for use within clinical practice and research.

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The (p)ppGpp synthetase gene, relA, of Streptomyces clavuligerus was cloned, sequenced and shown to be located in a genomic region that is highly conserved in other Streptomyces species. relA-disrupted and relA-deleted mutants of S. clavuligerus were constructed, and both were unable to form aerial mycelium or to sporulate, but regained these abilities when complemented with wild-type relA. Neither ppGpp nor pppGpp was detected in the S. clavuligerus relA-deletion mutant. In contrast to another study, clavulanic acid and cephamycin C production increased markedly in the mutants compared to the wild-type strain; clavulanic acid production increased three- to fourfold, while that of cephamycin C increased about 2.5-fold. Complementation of the relA-null mutants with wild-type relA decreased antibiotic yields to approximately wild-type levels. Consistent with these observations, transcription of genes involved in clavulanic acid (ceaS2) or cephamycin C (cefD) production increased dramatically in the relA-deleted mutant when compared to the wild-type strain. These results are entirely consistent with the growth-associated production of both cephamycin C and clavulanic acid, and demonstrate, apparently for the first time, negative regulation of secondary metabolite biosynthesis by (p)ppGpp in a Streptomyces species of industrial interest.

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BACKGROUND: Apraxia is a cognitive disorder that can occur after stroke. It prevents a person from carrying out a learned movement. Various interventions are used to treat apraxia but evidence of their benefit has been lacking. OBJECTIVES: To determine which therapeutic interventions targeted at motor apraxia reduce disability. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (last searched November 2006). In addition, we searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2006), MEDLINE (1966 to November 2007), EMBASE (1980 to November 2006), CINAHL (1982 to November 2006), PsycINFO (1974 to November 2006), the Research Index of the Occupational Therapy Journal (searched November 2006), REHABDATA (1956 to November 2006), the National Research Register (searched November 2006) and Current Controlled Trials Register (searched November 2006). We reviewed the reference lists of all articles that we identified as relevant. We made efforts to find both published and unpublished trials by writing to key authors and journals. SELECTION CRITERIA: Randomised controlled trials of therapeutic intervention for motor apraxia in stroke. DATA COLLECTION AND ANALYSIS: One review author searched the titles, abstracts and keywords. Four review authors extracted data and analysed trial quality. We contacted investigators for further details of trials if necessary. MAIN RESULTS: Three trials including a total of 132 participants were included in the review. There was evidence of a small and short-lived therapeutic effect in the two studies that reported change in activities of daily living (102 participants) but this was not considered clinically significant and did not persist at the longer-term follow up. AUTHORS' CONCLUSIONS: There is insufficient evidence to support or refute the effectiveness of specific therapeutic interventions for motor apraxia after stroke. Further research of higher quality is required. As we did not review whether patients with apraxia benefit from rehabilitation input in general, they should continue to receive general stroke rehabilitation services.

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BACKGROUND: Apraxia of speech is a communication disorder that can affect stroke patients. Several different intervention strategies are undertaken by speech and language therapists working with this patient group. OBJECTIVES: To assess whether therapeutic interventions improve functional speech in stroke patients with apraxia of speech and which individual therapeutic interventions are effective. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (searched May 2004). In addition, we searched the following databases: the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2003); MEDLINE (1966 to April 2004); EMBASE (1980 to April 2004); CINAHL (1982 to April 2004); PsycINFO (1974 to April 2004); the National Research Register (searched April 2004); and Current Controlled Trials Register (searched May 2004). We reviewed reference lists of relevant articles and contacted authors and researchers in an effort to identify published and unpublished trials. SELECTION CRITERIA: We sought to include randomised controlled trials of non-drug interventions for adults with apraxia of speech following a stroke where the primary outcome was functional speech at six months follow up. DATA COLLECTION AND ANALYSIS: One author searched the titles, abstracts and keywords. Two authors examined the abstracts that might meet the inclusion criteria. Four authors were available to assess trial quality and to extract data from eligible studies. MAIN RESULTS: No trials were identified. AUTHORS' CONCLUSIONS: There is no evidence from randomised trials to support or refute the effectiveness of therapeutic interventions for apraxia of speech. There is a need for high quality randomised trials to be undertaken in this area.

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The newly sequenced genome of Streptomyces coelicolor is estimated to encode 7825 theoretical proteins. We have mapped approximately 10% of the theoretical proteome experimentally using two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. Products from 770 different genes were identified, and the types of proteins represented are discussed in terms of their annotated functional classes. An average of 1.2 proteins per gene was observed, indicating extensive post-translational regulation. Examples of modification by N-acetylation, adenylylation and proteolytic processing were characterized using mass spectrometry. Proteins from both primary and certain secondary metabolic pathways are strongly represented on the map, and a number of these enzymes were identified at more than one two-dimensional gel location. Post-translational modification mechanisms may therefore play a significant role in the regulation of these pathways. Unexpectedly, one of the enzymes for synthesis of the actinorhodin polyketide antibiotic appears to be located outside the cytoplasmic compartment, within the cell wall matrix. Of 20 gene clusters encoding enzymes characteristic of secondary metabolism, eight are represented on the proteome map, including three that specify the production of novel metabolites. This information will be valuable in the characterization of the new metabolites.

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Glutamine synthetase I (GSI) enzyme activity in Streptomyces coelicolor is controlled post-translationally by the adenylyltransferase (GlnE) as in enteric bacteria. Although other homologues of the Escherichia coli Ntr system (glnK, coding for a PII family protein; and glnD, coding for an uridylyltransferase) are found in the S. coelicolor genome, the regulation of the GSI activity was found to be different. The functions of glnK and glnD were analysed by specific mutants. Surprisingly, biochemical assay and two-dimensional PAGE analysis showed that modification of GSI by GlnE occurs normally in all mutant strains, and neither GlnK nor GlnD are required for the regulation of GlnE in response to nitrogen stimuli. Analysis of the post-translational regulation of GlnK in vivo by two-dimensional PAGE and mass spectrometry indicated that it is subject to both a reversible and a non-reversible modification in a direct response to nitrogen availability. The irreversible modification was identified as removal of the first three N-terminal amino acid residues of the protein, and the reversible modification as adenylylation of the conserved tyro-sine 51 residue that is known to be uridylylated in E. coli. The glnD insertion mutant expressing only the N-terminal half of GlnD was capable of adenylylating GlnK, but was unable to perform the reverse deadenylylation reaction in response to excess ammonium. The glnD null mutant completely lacked the ability to adenylylate GlnK. This work provides the first example of a PII protein that is modified by adenylylation, and demonstrates that this reaction is performed by a homologue of GlnD, previously described only as a uridylyltransferase enzyme.

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Analysis of proteins recovered in the S100 precipitate fraction of Streptomyces griseus after ultracentrifugation led to the identification of a 52-kDa protein which is produced during the late growth phase. The gene (eshA) which codes for this protein was cloned from S. griseus, and then its homologue was cloned from Streptomyces coelicolor A3(2). The protein was deduced to be 471 amino acids in length. The protein EshA is characterized by a central region that shows homology to the eukaryotic-type cyclic nucleotide-binding domains. Significant homology was also found to MMPI in Mycobacterium leprae, a major antigenic protein to humans. The eshA gene mapped near the chromosome end and was not essential for viability, as demonstrated by gene disruption experiments, but its disruption resulted in the abolishment of an antibiotic (actinorhodin but not undecylprodigiosin) production. Aerial mycelium was produced as abundantly as by the parent strain. Expression analysis of the EshA protein by Western blotting revealed that EshA is present only in late-growth-phase cells. The eshA gene was transcribed just preceding intracellular accumulation of the EshA protein, as determined by S1 nuclease protection, indicating that EshA expression is regulated at the transcription level. The expression of EshA was unaffected by introduction of the relA mutation, which blocks ppGpp synthesis.

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In 1997 Salford Community Healthcare Trust embarked on a research project (funded by NHS Executive North West Region) to investigate how viable the Hanen Parent Programme (HPP) (Manolson 1992) was in terms of its effectiveness and suitability for an inner-city UK population in comparison with clinic-based, direct intervention. An important component of that research project involved exploring the parents' perceptions of the therapy they had undertaken. In this paper are summarised the areas in which there were marked differences between parents' experiences and perceptions of therapy as a result of the type of intervention they received. Clinical implications are discussed.

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Deletion of the (p)ppGpp synthetase gene, relA, of Streptomyces coelicolor A3(2) results in loss of production of the antibiotics actinorhodin (Act) and undecylprodigiosin (Red) and delayed morphological differentiation when the mutant is grown under conditions of nitrogen limitation. To analyze the role of (p)ppGpp as an intracellular signaling molecule for the initiation of antibiotic production, several C-terminally deleted derivatives of S. coelicolor relA that could potentially function in the absence of ribosome activation were placed under the control of the thiostrepton-inducible tipA promoter. While 0.82- and 1.28-kb N-terminal segments failed to restore (p)ppGpp and antibiotic production upon induction in a relA null mutant, 1.46- and 2.07-kb segments did. Under conditions of phosphate limitation, deletion of relA had little or no effect on Act or Red synthesis, potentially reflecting an alternative mechanism for ppGpp synthesis. A second S. coelicolor RelA homologue (RshA, with 42% identity to S. coelicolor RelA) was identified in the genome sequence. However, deletion of rshA had no effect on the ability of the relA mutant to make Act and Red when grown under conditions of phosphate limitation. While high-level induction of tipAp::rshA in the relA mutant resulted in growth inhibition, low-level induction restored antibiotic production and sporulation. In neither case, nor in the relA mutant that was grown under phosphate limitation and producing Act and Red, could (p)ppGpp synthesis be detected. Thus, a ppGpp-independent mechanism exists to activate antibiotic production under conditions of phosphate limitation that can be mimicked by overexpression of rshA.

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Production of ppGpp in Streptomyces coelicolor A3(2) was achieved independently of amino acid limitation by placing N-terminal segments of the ppGpp synthetase gene, relA, under the control of a thiostrepton-inducible promoter (tipAp). S1 nuclease protection experiments indicated that induced ppGpp concentrations of 6-12 pmol mg(-1) dry weight in late-exponential phase cultures caused activation of transcription of actII-ORF4, the pathway-specific activator gene for actinorhodin production. This level of ppGpp had no effect on growth rate, implying a causal role for ppGpp in activating actII-ORF4 transcription. No effect was observed on the transcription of the corresponding and homologous activator gene for undecylprodigiosin production, redD, reflecting a requirement for additional regulatory factors for activation of its transcription. This work provides the most compelling evidence yet for the activation of an antibiotic biosynthetic pathway by the stringent factor ppGpp.

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Considerable progress has been made in improving the control of chemotherapy-induced emesis. The impact of available antiemetic options for patients receiving stem cell transplants is unclear, as few prospective data have been collected. We prospectively evaluated antiemetic outcome in patients receiving stem cell transplantation over a 7-day period following the initiation of chemotherapy. The primary endpoints were the number of emetic episodes and the extent of nausea measured on a four-point scale. Eighty-two patients were evaluated. Ninety-five percent of patients had nausea during the first week of treatment; 80% had at least one emetic episode. The percentage of patients with emesis was as follows: day 1: 13%, day 2: 21%, day 3: 30%, day 4: 38%, day 5: 44%, day 6: 39%, day 7: 18%. In multivariate analysis, gender, emesis with prior chemotherapy, history of morning or motion sickness, type of transplant (auto vs allo), use of total body irradiation, or use of dexamethasone did not effect emesis control. Most patients receiving high-dose chemotherapy experience incompletely controlled emesis. Control of nausea and emesis progressively worsened with each subsequent day following initiation of chemotherapy, reaching a nadir on day 5. New treatment approaches are needed to improve emesis control in this patient population.

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OBJECTIVE: To determine the inter/intra-rater reliability of expert physiotherapists (PTs) measuring post-stroke shoulder pain with 100 mm vertical visual analogue scales (VAS; intensity, frequency and affective response) and a categorical site-of-pain scale. DESIGN: Three PTs independently rated subjects (normal clinical procedure but with a standardized starting position) on three days, at the same time of day, during one week in a randomized order determined by a nested latin square. Reliability for VAS scores was determined with the intraclass correlation coefficient (ICC) and for site-of-pain with the kappa statistic (kappa). Acceptable reliability was set at 0.75. The limits of agreement were also calculated. SETTING: Community. SUBJECTS: Thirty-three patients, mean time post stroke 42 months (range 7-360). RESULTS: Mean inter-rater reliability was 0.79 for intensity, 0.75 for frequency and 0.62 for affective response (ICC). The limits of agreement were wide and rater bias was significant for 6/27 ratings. Mean intra-rater reliability was 0.70 for intensity, 0.77 for frequency and 0.69 for affective response (ICC). For site-of-pain inter-rater reliability ranged from 0.156 (kappa) to 0.385 (kappa) and intrarater reliability ranged from 0.300 (kappa) to 0.559 (kappa). CONCLUSIONS: Although inter-rater reliability was acceptable for intensity and frequency there was a consistently large systematic bias between pairs of raters. Agreement might be improved if a standardized assessment procedure was used and/or if training in pain behaviour interpretation was provided.

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Sixty-one children, aged 3.6-5.0, with developmental phonological disorders (PD) participated in a study comparing the effects of metaphonologically (MET) or articulation-based (ART) therapy. Maturational effects were controlled for by the inclusion of 59 normally speaking control children of the same age range. Measures of phonological (speech) output and phonological awareness were taken before and after therapy for all subjects and at 3 months post-therapy for PD children. Results showed that PD children improved significantly in both phonological output and awareness skills across the intervention period compared with control children, but that there was no significant difference on the awareness measure between ART and MET groups. ART and MET groups differed from each other on one measure of speech improvement only, with the ART group making more change than the MET group on individual probe scores. Follow-up measures for both therapy groups indicated that there was little difference between the groups on phonological awareness change or speech development 3 months after intervention, though there was a trend for MET children to continue to make more long-term change than the ART group on one output measure. Additional analysis showed that there were generally few significant implications for outcome between PD children with good initial phonological awareness skills and those who initially had poor phonological awareness skills.

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In this pilot trial, the antiemetic efficacy and tolerability of an all-oral antiemetic combination in the prevention of both acute and delayed nausea and vomiting following high-dose cisplatin was evaluated. Fifty-two patients receiving cisplatin (median dose 100 mg/m2) were entered. Patients received (1) 60 min prior to cisplatin: prochlorperazine spansule 15 mg, dexamethasone 20 mg, granisetron 2 mg; (2) 12 h after cisplatin: prochlorperazine spansule 15 mg, dexamethasone 10 mg; (3) on days 2 and 3: prochlorperazine spansule 15 mg b.i.d., dexamethasone 8 mg b.i.d.; (4) on days 4 and 5: dexamethasone 4 mg b.i.d. All antiemetics were administered orally. The study period was the 120 h after cisplatin administration. The primary efficacy end-point was complete control (no vomiting, retching or antiemetic rescue) of delayed emesis (24-120 h after cisplatin). Complete control of delayed emesis was achieved in 26 patients (53%). Nineteen patients (39%) noted no delayed nausea. Complete control of acute emesis (24 h after cisplatin) was attained in 44 patients (86%). The no nausea rate during the first 24 h was 74%. Overall, 39 patients (80%) were satisfied or very satisfied with their outcome. Treatment was well tolerated with infrequent and minor adverse events. In conclusion, an all-oral combination of granisetron, dexamethasone and prochlorperazine is a highly effective and well-tolerated regimen for preventing acute cisplatin-induced emesis. Control of delayed emesis was not better than with current standard treatment, and more effective approaches are needed.

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The effectiveness of speech and language therapy for developmental phonological disorders has typically been measured in terms of the diminution of the application of phonological processes. Often substantial amounts of intervention and time may be needed to show up such changes. Shorter and more clinically realistic intervention regimes can result in small but significant changes in speech production which represent positive developments in the phonological system. In order to measure progress in this sort of therapy a sensitive instrument of measurement is required. In this paper we describe a research measurement tool, the probe scoring system, which was designed to detect small changes in the child's phonological system following therapy and contrast it to some of the instruments selected for use in other efficacy studies. The potential for wider clinical application is also considered.

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A RelC deletion mutant, KO-100, of Streptomyces coelicolor A3(2) has been isolated from a collection of spontaneous thiostrepton-resistant mutants. KO-100 grows as vigorously as the parent strain and possesses a 6-bp deletion within the rplK, previously termed relC. When the wild-type rplK gene was propagated on a low-copy-number vector in mutant KO-100, the ability to produce ppGpp, actinorhodin and undecylprodigiosin, which had been lost in the RelC mutant, was completely restored. Allele replacement by gene homogenotization demonstrated that the RelC mutation is responsible for the resistance to thiostrepton and the inactivation of ppGpp, actinorhodin and undecylprodigiosin production. Western blotting showed that ribosomes from the RelC mutant KO-100 contain only one-eighth the amount of L11 protein found in ribosomes of the parent strain. The impairment of antibiotic production in KO-100 could be rescued by the introduction of mutations that confer resistance to streptomycin (str), which result in alteration of Lys-88 in ribosomal protein S12 to Glu or Arg. No accompanying restoration of ppGpp synthesis was detected in these RelC str double mutants.

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