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In June 2014, Singapore seized 29,434 rosewood logs worth US$50 million that were illegally exported from Madagascar, marking one of the largest-ever seizures of CITES-protected species. Rosewood, highly prized for its unique properties and coloration, is obtained from genera in several families, including Fabaceae (in particular I Dalbergia i ), Meliaceae, and Proteaceae, and ebony comes primarily from species of I Diospyros i and I Euclea i (Ebenaceae); the taxonomy of most of these remains inadequate (Waeber et al. [8]). [Extracted from the article]

This article estimates a dynamic structural model of firm R&D investment in twelve Swedish manufacturing industries and uses it to measure rates of return to R&D and to simulate the impact of trade restrictions on the investment incentives. Export market profits are a substantial source of the expected return to R&D. R&D spending is found to have a larger impact on firm productivity in the export market than in the domestic market. Counterfactual simulations show that trade restrictions lower both the expected return to R&D and R&D investment level, thus reducing an important source of the dynamic gains from trade. A 10% tariff on Swedish exports reduces the expected benefits of R&D for the median firm by 18.6% and lowers the amount of R&D spending by 7.6% in the high-tech industries. The corresponding reductions in the low-tech industries are 20.6% and 5.5%, respectively. R&D adjustments in response to export tariffs mainly occur on the intensive, rather than the extensive, margin. [ABSTRACT FROM AUTHOR]

Objectives Diagnosing the idiopathic inflammatory myopathies (IIMs) can be challenging as several conditions, including genetic myopathies such as limb girdle muscular dystrophy type R12 (LGMD 2 l, anoctaminopathy) mimic the presentation. Here we describe learning points identified from review of four patients with LGMD 2 l who were initially incorrectly diagnosed with IIM. Our aim is to provide clinicians working in adult rheumatology services with a toolkit to help identify non-inflammatory presentations of myopathy. Methods We performed retrospective review of medical notes, laboratory results, muscle imaging and histological findings of four patients with LGMD 2 l who were previously misdiagnosed with IIM. We focussed on clinical presentation and progression, therapeutic agents used and events leading to revision of the diagnosis. Results Three male patients and one female patient with a mean age of 51 years at presentation were reviewed. In each case, treatment with immunosuppressants, in one case for >15 years, was observed without a clear therapeutic response. All patients were negative for anti-nuclear antibodies and available myositis-associated/specific autoantibodies and associated connective tissue disease features were absent. Prominent fatty infiltration and selective muscle involvement on thigh MRI was found in common. Conclusions Adult-onset genetic myopathies, particularly LGMD R12, can mimic IIM. Accurate diagnosis is crucial to avoid the use of potentially harmful immunosuppressive therapies, to allow appropriate genetic counselling and to facilitate involvement in research studies. [ABSTRACT FROM AUTHOR]

In this retrospective, multicentre, observational cohort study, we sought to determine the clinical, radiological, EEG, genetics and neuropathological characteristics of mitochondrial stroke-like episodes and to identify associated risk predictors. Between January 1998 and June 2018, we identified 111 patients with genetically determined mitochondrial disease who developed stroke-like episodes. Post-mortem cases of mitochondrial disease (n = 26) were identified from Newcastle Brain Tissue Resource. The primary outcome was to interrogate the clinico-radiopathological correlates and prognostic indicators of stroke-like episode in patients with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome (MELAS). The secondary objective was to develop a multivariable prediction model to forecast stroke-like episode risk. The most common genetic cause of stroke-like episodes was the m.3243A>G variant in MT-TL1 (n = 66), followed by recessive pathogenic POLG variants (n = 22), and 11 other rarer pathogenic mitochondrial DNA variants (n = 23). The age of first stroke-like episode was available for 105 patients [mean (SD) age: 31.8 (16.1)]; a total of 35 patients (32%) presented with their first stroke-like episode ≥40 years of age. The median interval (interquartile range) between first and second stroke-like episodes was 1.33 (2.86) years; 43% of patients developed recurrent stroke-like episodes within 12 months. Clinico-radiological, electrophysiological and neuropathological findings of stroke-like episodes were consistent with the hallmarks of medically refractory epilepsy. Patients with POLG-related stroke-like episodes demonstrated more fulminant disease trajectories than cases of m.3243A>G and other mitochondrial DNA pathogenic variants, in terms of the frequency of refractory status epilepticus, rapidity of progression and overall mortality. In multivariate analysis, baseline factors of body mass index, age-adjusted blood m.3243A>G heteroplasmy, sensorineural hearing loss and serum lactate were significantly associated with risk of stroke-like episodes in patients with the m.3243A>G variant. These factors informed the development of a prediction model to assess the risk of developing stroke-like episodes that demonstrated good overall discrimination (area under the curve = 0.87, 95% CI 0.82-0.93; c-statistic = 0.89). Significant radiological and pathological features of neurodegeneration were more evident in patients harbouring pathogenic mtDNA variants compared with POLG: brain atrophy on cranial MRI (90% versus 44%, P < 0.001) and reduced mean brain weight (SD) [1044 g (148) versus 1304 g (142), P = 0.005]. Our findings highlight the often idiosyncratic clinical, radiological and EEG characteristics of mitochondrial stroke-like episodes. Early recognition of seizures and aggressive instigation of treatment may help circumvent or slow neuronal loss and abate increasing disease burden. The risk-prediction model for the m.3243A>G variant can help inform more tailored genetic counselling and prognostication in routine clinical practice. [ABSTRACT FROM AUTHOR]

Background Influenza activity in the 2020–2021 season was remarkably low, likely due to implementation of public health preventive measures such as social distancing, mask wearing, and school closure. With waning immunity, the impact of low influenza activity in the 2020–2021 season on the following season is unknown. Methods We built a multistrain compartmental model that captures immunity over multiple influenza seasons in the United States. Compared with the counterfactual case, where influenza activity remained at the normal level in 2020–2021, we estimated the change in the number of hospitalizations when the transmission rate was decreased by 20% in 2020–2021. We varied the level of vaccine uptake and effectiveness in 2021–2022. We measured the change in population immunity over time by varying the number of seasons with lowered influenza activity. Results With the lowered influenza activity in 2020–2021, the model estimated 102 000 (95% CI, 57 000–152 000) additional hospitalizations in 2021–2022, without changes in vaccine uptake and effectiveness. The estimated changes in hospitalizations varied depending on the level of vaccine uptake and effectiveness in the following year. Achieving a 50% increase in vaccine coverage was necessary to avert the expected increase in hospitalization in the next influenza season. If the low influenza activity were to continue over several seasons, population immunity would remain low during those seasons, with 48% of the population susceptible to influenza infection. Conclusions Our study projected a large compensatory influenza season in 2021–2022 due to a light season in 2020–2021. However, higher influenza vaccine uptake would reduce this projected increase in influenza. [ABSTRACT FROM AUTHOR]

Background Whole genome sequencing (WGS) surveillance and electronic health record data mining have the potential to greatly enhance the identification and control of hospital outbreaks. The objective was to develop methods for examining economic value of a WGS surveillance-based infection prevention (IP) program compared to standard of care (SoC). Methods The economic value of a WGS surveillance-based IP program was assessed from a hospital's perspective using historical outbreaks from 2011–2016. We used transmission network of outbreaks to estimate incremental cost per transmission averted. The number of transmissions averted depended on the effectiveness of intervening against transmission routes, time from transmission to positive culture results and time taken to obtain WGS results and intervene on the transmission route identified. The total cost of an IP program included cost of staffing, WGS, and treating infections. Results Approximately 41 out of 89 (46%) transmissions could have been averted under the WGS surveillance-based IP program, and it was found to be a less costly and more effective strategy than SoC. The results were most sensitive to the cost of performing WGS and the number of isolates sequenced per year under WGS surveillance. The probability of the WGS surveillance-based IP program being cost-effective was 80% if willingness to pay exceeded $2400 per transmission averted. Conclusions The proposed economic analysis is a useful tool to examine economic value of a WGS surveillance-based IP program. These methods will be applied to a prospective evaluation of WGS surveillance compared to SoC. [ABSTRACT FROM AUTHOR]

Objectives To assess the performance of the EULAR/ACR idiopathic inflammatory myopathies (IIMs) classification criteria in a cohort of incident IIM cases and examine how criteria-assigned IIM subtype correlates with expert opinion. Methods Adults with newly diagnosed IIM attending Salford Royal NHS Foundation Trust were identified over a 10 year period. A retrospective review of all putative cases was performed and those fulfilling a consensus expert opinion diagnosis of IIM were included. Clinical, serological and histological data were collected and each case was assigned a single IIM subtype. The EULAR/ACR classification criteria were then applied and sensitivity, specificity and positive and negative predictive values were calculated, presented with 95% CIs. Results A total of 1637 cases were screened, with 255 consensus expert opinion IIM cases ultimately identified. Applying the EULAR/ACR classification criteria, the sensitivity to diagnose an IIM was 99.6% (95% CI 97.2, 100) and 80.9% (95% CI 76.0, 85.8) for the criteria cut-points of probable and definite diagnoses, respectively. In 94/255 cases the IIM subtype differed between consensus expert opinion and classification criteria, most strikingly in the group subtyped as PM by the EULAR/ACR criteria, where there was discrepancy in the majority (i.e. in 87/161). Conclusion The EULAR/ACR criteria performed with high sensitivity in identifying IIM in this external cohort of incident IIM. However, substantial disagreements arose between consensus expert opinion and the criteria regarding IIM subtype assignments, resulting in a large proportion of criteria-assigned cases of PM having heterogeneous features. These results may have important implications for future use of these criteria in subsequent research. [ABSTRACT FROM AUTHOR]

This article discusses a new policy framework to appraise proposals of large transport infrastructure investments—transport corridors—and applies it to the China-Pakistan Economic Corridor (CPEC). The framework emphasises the need to focus appraisal on the ultimate benefits that households along a corridor and, more generally, society, can attain—such as increased consumption, better jobs and greater equity. It also emphasises the need to identify and manage trade-offs. The appraisal framework is applied to Pakistan's portion of the CPEC. Simulations suggest important heterogeneous impacts of CPEC among districts in Pakistan stemming from variations in restrictions on land use and in secondary education across connected districts. [ABSTRACT FROM AUTHOR]

In this article, we use micro data on both trade and production for a sample of large Chinese manufacturing firms in the footwear industry from 2002 to 2006 to estimate an empirical model of export demand, pricing, and market participation by destination market. We use the model to construct indexes of firm-level demand, marginal cost, and fixed cost. The empirical results indicate substantial firm heterogeneity in all three dimension with demand being the most dispersed. The firm-specific demand and marginal cost components account for over 30% of market share variation, 40% of sales variation, and over 50% of price variation among exporters. The fixed cost index is the primary factor explaining differences in the pattern of destination markets across firms. The estimates are used to analyse the supply reallocation following the removal of the quota on Chinese footwear exports to the EU. This led to a rapid restructuring of export supply sources on both the intensive and extensive margins in favour of firms with high demand and low fixed costs indexes, with marginal cost differences not being important. [ABSTRACT FROM AUTHOR]

Objectives. Limitations in the methods available for identifying cardiac involvement and accurately quantifying disease activity in the idiopathic inflammatory myopathies (IIMs) may contribute to poor outcomes. We investigated the utility of different serum muscle damage markers [total creatine kinase (CK), cardiac troponin T (cTnT) and cardiac troponin I (cTnI)] to address these issues. Methods. We assessed disease activity and cardiac involvement using the International Myositis Assessment and Clinical Studies Group core set measures in 123 participants with confirmed adultonset IIM from the UK and Denmark. Total CK, cTnT and cTnI were measured. Associations were assessed using logistic regression and Spearman's ranked correlation. Results. Cardiac involvement (n = 18) was associated with higher cTnI levels, independent of overall disease activity [adjusted odds ratio 1.03 (95% CI 1.01, 1.05); P = 0.002]. An abnormal cTnI had the highest specificity and positive predictive value for cardiac involvement (95% and 62%, respectively). In those with a normal CK but elevated cTnT or cTnI, an association with increased disease activity scores was observed. Serum cTnT correlated with the physician (ρ = 0.39) and patient-assessed (ρ = 0.28) global visual analogue scales and HAQ (ρ = 0.41) more strongly than CK or cTnI levels. cTnT was the only marker to correlate with manual muscle testing scores (ρ =-0.24). Conclusion. Serum cTnI testing may have a role in screening for cardiac involvement in IIMs. Abnormal levels of serum cTnT and cTnI are associated with increased disease activity, including in those with a normal CK. [ABSTRACT FROM AUTHOR]

This surveillance study describes 25 adults and children with acute neurological manifestations associated with influenza, mainly A(H1N1) 2009. Several children had specific encephalopathy syndromes with characteristic neuroimaging findings and poor outcomes. A modified classification system is proposed.Background. The emergence of influenza A(H1N1) 2009 was met with increased reports of associated neurological manifestations. We aimed to describe neurological manifestations of influenza in adults and children in the United Kingdom that presented at this time.Methods. A 2-year surveillance study was undertaken through the British adult and pediatric neurological surveillance units from February 2011. Patients were included if they met clinical case definitions within 1 month of proven influenza infection.Results. Twenty-five cases were identified: 21 (84%) in children and 4 (16%) in adults. Six (29%) children had preexisting neurological disorders. Polymerase chain reaction of respiratory secretions identified influenza A in 21 (81%; 20 of which [95%] were H1N1) and influenza B in 4 (15%). Twelve children had encephalopathy (1 with movement disorder), 8 had encephalitis, and 1 had meningoencephalitis. Two adults had encephalopathy with movement disorder, 1 had encephalitis, and 1 had Guillain-Barré syndrome. Seven individuals (6 children) had specific acute encephalopathy syndromes (4 acute necrotizing encephalopathy, 1 acute infantile encephalopathy predominantly affecting the frontal lobes, 1 hemorrhagic shock and encephalopathy, 1 acute hemorrhagic leukoencephalopathy). Twenty (80%) required intensive care, 17 (68%) had poor outcome, and 4 (16%) died.Conclusions. This surveillance study described a cohort of adults and children with neurological manifestations of influenza. The majority were due to H1N1. More children than adults were identified; many children had specific encephalopathy syndromes with poor outcomes. None had been vaccinated, although 8 (32%) had indications for this. A modified classification system is proposed based on our data and the increasing spectrum of recognized acute encephalopathy syndromes. [ABSTRACT FROM PUBLISHER]

Waldenström macroglobulinemia (WM) is characterized by monoclonal gammopathy, usually IgM, in association with lymphoplasmacytic lymphoma (LPL). Little is known of the expression of nuclear proteins involved in B-cell development in LPL/WM. In this study, the expression patterns of PAX5/BSAP, MUM1/IRF4, and PRDM1/BLIMP1 were analyzed in plasma cells and lymphocytes in 29 cases of newly diagnosed LPL/WM by double immunohistochemical staining with CD138 and CD22. These patterns were compared with the expression profiles seen in normal bone marrow samples, reactive tonsils, and cases of plasma cell myeloma and marginal zone lymphoma. The median percentage of plasma cells coexpressing CD138 and PAX5 was significantly higher in LPL/WM compared with benign tissues (P = .001), marginal zone lymphoma (P = .002), and plasma cell myeloma (P < .0001), whereas the median percentage of plasma cells coexpressing CD138 and MUM1 was lower in LPL/WM than plasma cells in benign tissues (P = .02), marginal zone lymphoma (P = .001), and plasma cell myeloma (P = .0002). These findings show that a subset of plasma cells in LPL/WM demonstrates a nuclear protein expression pattern characteristic of the B-cell developmental program. Thus, the results better define the immunophenotypic profile of the neoplastic cells in LPL/WM. [ABSTRACT FROM AUTHOR]

Mutations in the nuclear-encoded mitochondrial maintenance gene RRM2B are an important cause of familial mitochondrial disease in both adults and children and represent the third most common cause of multiple mitochondrial DNA deletions in adults, following POLG [polymerase (DNA directed), gamma] and PEO1 (now called C10ORF2, encoding the Twinkle helicase) mutations. However, the clinico-pathological and molecular features of adults with RRM2B-related disease have not been clearly defined. In this multicentre study of 26 adult patients from 22 independent families, including five additional cases published in the literature, we show that extra-ocular neurological complications are common in adults with genetically confirmed RRM2B mutations. We also demonstrate a clear correlation between the clinical phenotype and the underlying genetic defect. Myopathy was a prominent manifestation, followed by bulbar dysfunction and fatigue. Sensorineural hearing loss and gastrointestinal disturbance were also important findings. Severe multisystem neurological disease was associated with recessively inherited compound heterozygous mutations with a mean age of disease onset at 7 years. Dominantly inherited heterozygous mutations were associated with a milder predominantly myopathic phenotype with a later mean age of disease onset at 46 years. Skeletal muscle biopsies revealed subsarcolemmal accumulation of mitochondria and/or cytochrome c oxidase-deficient fibres. Multiple mitochondrial DNA deletions were universally present in patients who underwent a muscle biopsy. We identified 18 different heterozygous RRM2B mutations within our cohort of patients, including five novel mutations that have not previously been reported. Despite marked clinical overlap between the mitochondrial maintenance genes, key clinical features such as bulbar dysfunction, hearing loss and gastrointestinal disturbance should help prioritize genetic testing towards RRM2B analysis, and sequencing of the gene may preclude performance of a muscle biopsy. [ABSTRACT FROM PUBLISHER]

The article discusses the use of an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method to measure 21 benzodiazepines, zopiclone and zolpidem in serum and plasma. It analyzes the serum and plasma specimen from 48 patients and compares the results to those derived from a previously published method. It is noted that the UPLC-MS-MS method shows reliable and fast results for the quantification of benzodiazepines and hypnotics.

Objectives Triazole antifungal drugs are the mainstay of treatment for patients with chronic pulmonary aspergillosis and are often used as steroid-sparing agents in patients with allergic aspergillosis. Peripheral neuropathy (PN) is a rare but reported side effect of triazole therapy in the acute management of invasive fungal infections, but its incidence during long-term triazole treatment for chronic aspergillosis is unknown. The goal of this study was to determine the incidence of PN in this context. Patients and methods A retrospective cohort study was carried out to collect data on all patients with chronic aspergillosis commenced on long-term triazole therapy at the National Aspergillosis Centre in Manchester between 2007 and 2010. Results Two hundred and twenty-two patients were commenced on triazole therapy. Ten percent developed PN after an average of 4 months. Seventeen percent of patients taking itraconazole, 9% taking voriconazole and 3% taking posaconazole developed PN. This is the first report of posaconazole-induced PN. Twenty-two episodes of PN presented as numbness or tingling in the extremities, while four episodes presented as predominant leg weakness. The majority of cases were axonal, length-dependent neuropathies that recovered after triazole medication was discontinued. Two patients had non-progressive but irreversible PN. Two patients were diagnosed with mononeuropathies. Conclusions A 10% incidence of PN was observed for patients commenced on triazole therapy for chronic aspergillosis. Patients on long-term triazole therapy should be monitored for neurological symptoms. If PN is suspected, diagnosis should include nerve conduction studies, exclusion of other causes and consideration of dose reduction or cessation of therapy. [ABSTRACT FROM PUBLISHER]

An introduction is presented in which the editor discusses various reports within the issue on topics including the analysis of density, distance and division (3Ds) in Chongqing, China, the process of rural-urban transformation, and the prevalence of rural-urban migration in developing countries.

This paper analyses the empirical relevance of the 2009 World Development Report's 3D framework for the explanation of spatial productivity disparities within Chongqing municipality's non-primary sector. In doing so, it presents evidence of a significant role for distance in determining these disparities, especially within the municipality's Southeast wing. The evidence of a role for density is more mixed, however, with findings of agglomeration economies depending on the method of estimation used. These results have important policy implications both for the municipality itself and China overall. [ABSTRACT FROM AUTHOR]

Clinicians may defer antiretroviral treatment for patients with suboptimal adherence. We used a validated computer simulation of HIV disease progression to compare alternative treatment thresholds for patients with suboptimal adherence. Earlier treatment increased life expectancy across a wide adherence range (50%-100% of doses taken). Delaying treatment for patients with suboptimal adherence may not always be appropriate. [ABSTRACT FROM AUTHOR]

Using a two-plasmid system, we recently identified σE-dependent promoters directing expression of the σE regulon genes in Salmonella enterica serovar Typhimurium ( S. Typhimurium). Comparison of the promoters revealed a consensus sequence almost identical to the σE-dependent rpoEp3 promoter directing expression of rpoE. This two-plasmid system was previously optimized to identify nucleotides critical for the rpoEp3 promoter activity. However, two highly conserved nucleotides in the σE consensus sequence were not identified by this screening. In the present study, we have improved the two-plasmid screening system using a new optimized error-prone PCR mutagenesis. Together with site-directed mutagenesis, we further identified nucleotides critical for activity of the rpoEp3 promoter and quantified the effect of the particular mutation upon promoter activity. All the identified critical nucleotides of the rpoEp3 promoter (in capital) were located in the −35 (ggAACtt) and −10 (gTCtaA) regions and corresponded to the most conserved nucleotides in the σE consensus sequence. The expression of the wild-type and mutated rpoEp3 promoters was confirmed in S. Typhimurium and was found to exhibit a different pattern of σE activation compared with Escherichia coli, with a peak rpoEp3 promoter activity in early stationary phase followed by a decrease in late stationary phase. [ABSTRACT FROM AUTHOR]

Vertebrates respond to environmental stressors through the neuro-endocrine stress response, which involves the production of glucocorticoids. We have selected independent, duplicate divergent lines of zebra finches for high, low and control corticosterone responses to a mild stressor. This experiment has shown that over the first four generations, the high lines have demonstrated a significant realized heritability of about 20%. However, the low lines have apparently not changed significantly from controls. This asymmetry in response is potentially because of the fact that all birds appear to be showing increased adaptation to the environment in which they are housed, with significant declines in corticosterone response in control lines as well as low lines. Despite the existence of two- to threefold difference in mean corticosterone titre between high and low lines, there were no observed differences in testosterone titre in adult male birds from the different groups. In addition, there were no consistent, significant differences between the lines in any of the life history variables measured – number of eggs laid per clutch, number of clutches or broods produced per pair, number of fledglings produced per breeding attempt, nor in any of egg, nestling and fledgling mortality. These results highlight the fact that the mechanisms that underlie variation in the avian physiological system can be modified to respond to differences between environments through selection. This adds an additional level of flexibility to the avian physiological system, which will allow it to respond to environmental circumstances. [ABSTRACT FROM AUTHOR]

We previously described a two-plasmid system for the identification of promoters recognized by Salmonella enterica serovar Typhimurium (S. Typhimurium) σE. The S. Typhimurium σE-dependent rpoEp3 promoter was active in the E. coli two-plasmid system only after arabinose-induced expression of S. Typhimurium rpoE. In the present study, we have exploited this two-plasmid system for the identification of nucleotides critical for activity of the rpoEp3 promoter. A library of randomly mutated DNA fragments containing the rpoEp3 promoter was cloned upstream of a lacZα reporter gene and screened for activity in the presence of S. Typhimurium σE. The clones exhibiting reduced LacZ activity were sequenced to identify the mutations. The activity of the mutated rpoEp3 promoters were studied further using a luciferase-based promoter-probe plasmid. All of the important nucleotides of the rpoEp3 promoter (in capital) were located in the −35 (ggAActt) and −10 (TctaA) regions. The critical nucleotides were also the most conserved in known σE-dependent promoters. The study also revealed the importance of the 16-bp spacing between −10 and −35 region, as reducing the spacing to 15-bp greatly reduced activity of the promoter. This method should be generally applicable for the identification of important nucleotides in the cognate promoters of other σ factors. [Copyright &y& Elsevier]

We assessed the degree of population subdivision among global populations of green sea turtles, Chelonia mydas, using four microsatellite loci. Previously, a single-copy nuclear DNA study indicated significant male- mediated gene flow among populations alternately fixed for different mitochondrial DNA haplotypes and that genetic divergence between populations in the Atlantic and Pacific Oceans was more common than subdivisions among populations within ocean basins. Even so, overall levels of variation at single-copy loci were low and inferences were limited. Here, the markedly more variable microsatellite loci confirm the presence of male-mediated gene flow among populations within ocean basins. This analysis generally confirms the genetic divergence between the Atlantic and Pacific. As with the previous study, phylogenetic analyses of genetic distances based on the microsatellite loci indicate a close genetic relationship among eastern Atlantic and Indian Ocean populations. Unlike the single-copy study, however, the results here cannot be attributed to an artifact of general low variability and likely represent recent or ongoing migration between ocean basins. Sequence analyses of regions flanking the microsatellite repeat reveal considerable amounts of cryptic variation and homoplasy and significantly aid in our understanding of population connectivity. Assessment of the allele frequency distributions indicates that at least some of the loci may not be evolving by the stepwise mutation model. [ABSTRACT FROM AUTHOR]

The rpoE gene of Salmonella enterica serovar Typhimurium (S. Typhimurium), which encodes the extracytoplasmic stress response sigma factor σE, is critically important for the virulence of S. Typhimurium. We analysed expression of rpoE by wild-type and mutant bacteria grown in different conditions by S1-nuclease mapping using RNA, and using in vivo reporter gene fusions. Three promoters, rpoEp1, rpoEp2 and rpoEp3, were located upstream of the S. Typhimurium rpoE gene. The promoters were differentially expressed during growth and under several stress conditions including cold shock. Expression from the rpoEp3 promoter was absent in an S. Typhimurium rpoE mutant, demonstrating its dependence upon σE. The level of mRNA corresponding to rpoEp3 was also higher in a cpxR mutant, indicating a negative regulation of the promoter by the Cpx system. Using this rpoE-dependent promoter, we optimised a two-plasmid system for identification of promoters recognised by S. Typhimurium σE. The rpoEp3 promoter was active in the Escherichia coli two-plasmid system and has an identical transcription start point as in S. Typhimurium but only after induction of S. Typhimurium rpoE expression. [Copyright &y& Elsevier]

A previously established method, based on a two-plasmid system, was used to identify promoters recognized by RNA polymerase containing the extracytoplasmic stress response sigma factor σE in Escherichia coli. In addition to previously identified rpoE-dependent promoters, 11 new promoters potentially directing the expression of 15 genes were identified that were active only after over-expression of rpoE. The promoters were confirmed and transcriptional start points of the promoters were determined by primer extension analysis and S1-nuclease mapping. All the promoters contained sequences similar to the consensus sequence of rpoE-dependent promoters. The new rpoE-dependent promoters governed expression of genes encoding proteins involved in primary metabolism (fusA, tufA, recR), phospholipid and lipopolysaccharide biosynthesis (psd, lpxP), signal transduction (sixA), proposed inner or outer membrane proteins (bacA, sbmA, smpA, yeaY), and proteins with unknown function (ybaB, yaiW, yiiS, yiiT, yfeY). [Copyright &y& Elsevier]

Bordetella pertussis and Bordetella bronchiseptica are respiratory pathogens of humans and animals respectively. Unlike many bacteria, they are able to efficiently colonise healthy ciliated respiratory mucosa. This characteristic of Bordetella spp. can potentially be exploited to develop efficient live vaccines and vectors for delivery of heterologous antigens to the respiratory tract. Here we review the progress in this area. [Copyright &y& Elsevier]

The article provides an analysis of the link between a producer's total factor productivity and its decision to participate in the export market using manufacturing data from Republic of Korea and Taiwan. It is stated that at a minimum, the ability to export has allowed manufacturers to specialize in a range of products and increase their output beyond what the size of their domestic market could support. In Taiwan, the export participation rate in electronics is 41% while Korea has a 26% rate.

Attempts to determine the underlying cause of hysteria by going through medicine's history. Concept of hysteria according to Hippocrates and Galen; Medical theories of Samuel A. Cartwright; Definition and diagnosis of the disorder similar to that found in the persecution of witchcraft.

Risk factors for invasive fungal infection in patients undergoing orthotopic liver transplantation were examined. Thirty-four of 168 transplants were complicated within 100 days after transplantation by documented invasive fungal infection (Candida species, 28 patients; mycelial fungi, 5; both Candida and Aspergillus species, 1). In the multivariate Cox proportional hazards model, three baseline and two posttransplant variables were independently significant risk factors for infection: level of creatinine (hazard ratio = 1.4), length of transplant operation (HR = 1.2), retransplantation (HR = 3.2), abdominal or intrathoracic reoperations (HR = 2.5), and cytomegalovirus infection (HR = 8.5). Four predictors (creatinine of >3.0 mg/dl., operative time of > 11 h, retransplantation, and early colonization) assessable at the time of transplantation or shortly thereafter were incorporated into a simple predictive model for risk stratification. The risk of invasive fungal infection ranged from 1% in patients with no predictors to 67% in patients with two or more predictors. Strategies to prevent invasive fungal infections after liver transplantation should be targeted to these high-risk groups. [ABSTRACT FROM PUBLISHER]

This paper examines the patterns of postentry employment growth and failure for over 200,000 plants that entered the U. S. manufacturing sector in the 1967-1977 period. The postentry patterns of growth and failure vary significantly with observable employer characteristics. Plant failure rates decline with size and age as do the growth rates of nonfailing plants. The expected growth rate of a plant, which depends on the net effect of these two forces, declines with size for plants owned by single-plant firms but increases with size for plants owned by multiplant firms. [ABSTRACT FROM AUTHOR]