Uncertainty in phosphorus fluxes and budgets across the U.S. long-term agroecosystem research network

Phosphorus (P) budgets can be useful tools for understanding nutrient cycling and quantifying the effectiveness of nutrient management planning and policies; however, uncertainties in agricultural nutrient budgets are not often quantitatively assessed. The objective of this study was to evaluate uncertainty in P fluxes (fertilizer/manure application, atmospheric deposition, irrigation, crop removal, surface runoff, leachate) and the propagation of these uncertainties to annual P budgets. Data from 56 cropping systems in the P-FLUX database, which spans diverse rotations and landscapes across the U.S. and Canada, were evaluated. Results showed that across cropping systems, average annual P budget was 22.4 kg P ha^-1 (range = -32.7 to 340.6 kg P ha^-1 ), with an average uncertainty of 13.1 kg P ha^-1 (range = 1.0 to 87.1 kg P ha^-1 ). Fertilizer/manure application and crop removal were the largest P fluxes across cropping systems and, as a result, accounted for the largest fraction of uncertainty in annual budgets (61 and 37%, respectively). Remaining fluxes individually accounted for <2% of the budget uncertainty. Uncertainties were large enough that determining whether P was increasing, decreasing, or not changing was inconclusive in 39% of the budgets evaluated. Findings indicate that more careful and/or direct measurements of inputs, outputs, and stocks are needed. Recommendations for minimizing uncertainty in P budgets based on the results of the study were developed. Quantifying, communicating, and constraining uncertainty in budgets among production systems and multiple geographies is critical for engaging stakeholders, developing local and national strategies for P reduction, and informing policy. This article is protected by copyright. All rights reserved.

Is laparoscopy still of value in managing the patient with abdominal trauma?

Introduction

Stabbings are an increasing international problem and the UK is not exempt. Although the incidence and costs of negative laparotomy are well known, and laparoscopy has been available for over 100 years, it is only in the last three decades that has seen its effective utilization in trauma both as a diagnostic and therapeutic modality.

Methods

A retrospective two-year study of all patients undergoing laparoscopy for suspicion of diaphragmatic injury or breach of the peritoneum who were haemodynamically stable from non-ballistic penetrating torso trauma at St Mary’s Hospital (Imperial Healthcare Trust).

Results

Three groups of patients were identified: diagnostic laparoscopy without injury (n = 31), laparoscopy with injury ± laparoscopic treatment (n = 41) and diagnostic laparoscopy converted to laparotomy (n = 10). The patients who had laparoscopic intervention had a shorter hospital stay (2 vs. 5 days, p = 0.004), decreased intensive treatment unit admission (p = 0.007) and decreased intensive treatment unit stay (p = 0.007) compared to those who had conversion to laparotomy.

Conclusion

Trauma laparoscopy is a useful modality in managing selected trauma patient with suspected intra-abdominal injuries and can avoid unnecessary laparotomy. It is associated with a shorter hospital stay.

Genomic analysis uncovers a phenotypically diverse but genetically homogeneous Escherichia coli ST131 clone circulating in unrelated urinary tract infections

OBJECTIVES

To determine variation at the genome level in Escherichia coli ST131 clinical isolates previously shown to be phenotypically diverse.

METHODS

The genomes of 10 ST131 isolates extensively characterized in previous studies were sequenced using combinations of Illumina and 454 sequencing technology. Whole-genome comparisons and phylogenetic comparisons were then performed across the strain set and with other closely related extraintestinal pathogenic E. coli (ExPEC) strain types.

RESULTS

E. coli ST131 is overrepresented in a collection of clinical isolates, and there is large phenotypic variation amongst isolates. In contrast, genome sequencing of a selection of non-related clinical isolates shows almost no genetic variation between ST131 strains, and E. coli ST131 shows evidence of a genetically monomorphic pathogen showing a similar evolutionary trend to hypervirulent Clostridium difficile.

CONCLUSIONS

A dominant circulating clone of E. coli ST131 has been identified in unrelated clinical urine samples in the UK. The clone splits into two distinct subgroups on the basis of antimicrobial resistance levels and carriage of extended-spectrum β-lactamase plasmids. This provides the most comprehensive snapshot to date of the true molecular epidemiology of ST131 clinical isolates.

Antiviral resistance during the 2009 influenza A H1N1 pandemic: public health, laboratory, and clinical perspectives

Influenza A H1N1 2009 virus caused the first pandemic in an era when neuraminidase inhibitor antiviral drugs were available in many countries. The experiences of detecting and responding to resistance during the pandemic provided important lessons for public health, laboratory testing, and clinical management. We propose recommendations for antiviral susceptibility testing, reporting results, and management of patients infected with 2009 pandemic influenza A H1N1. Sustained global monitoring for antiviral resistance among circulating influenza viruses is crucial to inform public health and clinical recommendations for antiviral use, especially since community spread of oseltamivir-resistant A H1N1 2009 virus remains a concern. Further studies are needed to better understand influenza management in specific patient groups, such as severely immunocompromised hosts, including optimisation of antiviral treatment, rapid sample testing, and timely reporting of susceptibility results.

Analysis of host response to bacterial infection using error model based gene expression microarray experiments

A key step in the analysis of microarray data is the selection of genes that are differentially expressed. Ideally, such experiments should be properly replicated in order to infer both technical and biological variability, and the data should be subjected to rigorous hypothesis tests to identify the differentially expressed genes. However, in microarray experiments involving the analysis of very large numbers of biological samples, replication is not always practical. Therefore, there is a need for a method to select differentially expressed genes in a rational way from insufficiently replicated data. In this paper, we describe a simple method that uses bootstrapping to generate an error model from a replicated pilot study that can be used to identify differentially expressed genes in subsequent large-scale studies on the same platform, but in which there may be no replicated arrays. The method builds a stratified error model that includes array-to-array variability, feature-to-feature variability and the dependence of error on signal intensity. We apply this model to the characterization of the host response in a model of bacterial infection of human intestinal epithelial cells. We demonstrate the effectiveness of error model based microarray experiments and propose this as a general strategy for a microarray-based screening of large collections of biological samples.

The study of child language in South Africa

This paper describes some of the research into child language that has been conducted in South Africa over the past 20 years. It is written from a clinical perspective and it describes the influence of changing demographic, social, educational and political variables on the study of child language. Specifically, the influence of the multilingual and multicultural nature of the society will be considered. Among issues discussed are the increasing research base on the acquisition of normal language, the adaptation of assessment tools and language in education.

Pragmatic assessment and therapy for persons with brain damage: what have clinicians gleaned in two decades?

Pragmatic competence comprises a number of interrelated skills which manifest in real-time in a range of adaptive behaviors and which are driven by underlying cognitive processes that appear to be variably compromised in brain damage. Differential neurological profiles reflect different pragmatic outcomes. The essence of pragmatic assessment and therapy for clinicians is therefore to capture accurately, measure, and, where possible, enhance the ability of the individual to adapt to a changing communicative environment. Assessment measures differ along a number of dimensions. A distinction is drawn between testing and assessment and the argument proposed that for clinical purposes, it is helpful to keep the notions of functional and pragmatic distinct.

Contemporary results of radical radiotherapy for bladder transitional cell carcinoma in a district general hospital with cancer-centre status

OBJECTIVE

To assess the current efficacy and safety of definitive external beam radiotherapy (EBRT) in the treatment of invasive bladder transitional cell carcinoma (TCC) in a district general hospital with cancer-centre status.

PATIENTS AND METHODS

The case notes of all patients with bladder TCC undergoing EBRT with curative intent over an 8-year period (1988-95) were reviewed. Additional missing outcome data were collected.

RESULTS

In all, 120 patients (109 men; median age 70 years, range 34-90) underwent radical EBRT (40-65 Gy; fraction median=20) over the 8-year period. Staging, as assessed by examination under anaesthesia and computed tomography, was T1 in 16%, T2 in 43%, T3 in 38% and T4 in 3%. In 96 patients (80%) the tumour was poorly differentiated (G3). The overall morbidity at 12 months was 12%; proctitis occurred in nine patients (8%) and cystitis in five (4%). Sixty-seven patients (59%) developed a local recurrence and in 36 (30%) this was invasive. The overall median survival was 60 months. Thirty-three patients underwent salvage cystectomy with a subsequent median survival of 12.5 months.

CONCLUSION

Modern radical multifraction EBRT in invasive bladder TCC has a low morbidity, with an overall median survival of 5 years.

The measurement of emotional reaction and depression in a South African stroke population

The study evaluated the sensitivity of a newly devised scale for measurement of emotional reactions and depression, on a group of 25 stroke patients, with right or left hemisphere damage, and 15 age-matched controls. Four clusters were examined: communication, expression of emotions, sense of self and physical or psychomotor problems. Case history factors such as time since onset, gender, anti-depressant medication and severity of aphasia were related to performance on the scale. Results indicated that the scale allowed for expression of emotion in all three groups tested and that speech and communication items significantly differentiated right and left hemisphere subjects. A strong correlation was found between spouse reports and self reports on selected items of the scale. Time since onset was found to be important in predicting level of depression. These findings have implications for assessment and management of stroke.

Toward a new psychometric definition of social disability in children with attention-deficit hyperactivity disorder

OBJECTIVE

To investigate a new mechanism for identifying social disability in children with attention-deficit hyperactivity disorder (ADHD), employing psychometric methodology used in defining learning disabilities.

METHOD

Two groups of index children were examined: 140 children with ADHD (referred from both psychiatric and pediatric sources) and 120 non-ADHD comparison children. Subjects were defined as socially disabled if they had a value greater than 1.65 on a standardized discrepancy score between observed and expected scores on a measure of social functioning (with expected scores derived as a function of the child's estimated Full Scale IQ). Children identified as socially disabled were compared with non-socially disabled probands on psychopathology, familiality, cognitive functioning, school history, and treatment history.

RESULTS

Using this psychometric approach, 22% of the ADHD probands qualified as socially disabled, whereas none of the comparison probands qualified (p < or = .001). Socially disabled ADHD probands were significantly more impaired than were non-socially disabled ADHD probands in global and specific measures of social functioning and patterns of psychiatric comorbidity.

CONCLUSIONS

The psychometrically defined construct of social disability may identify children with ADHD who are at very high risk for severe social dysfunction and whose course and prognosis may vary from those of other children with ADHD. This subgroup of children with ADHD may be at heightened risk for poor outcome, and their identification may facilitate the development of clinical interventions aimed at ameliorating their specific difficulties.

The persisting communicative difficulties of 'remediated' language-impaired children

This study addresses the effiacy of dismissal criteria used by speech and language pathologists by investigating communicative functioning in children declared 'remediated'. A battery of measures comprising the Language Assessment and Remediation Procedure (LARSP); the Behavioural inventory of Speech Act Performances (BISAP); the BISAP Addendum and the Devereux School Behaviour Rating Scale (DESB) was conducted on five children with language impairment who had been declared 'remediated'. Findings for certain 'remediated' subjects revealed persisting problems. The results suggest that decisions about dismissal from therapy may, in some cases, be premature and point to the need for a broad-based perspective concerning remediation dismissal decisions. An additional study on larger populations and the use of designs which investigate long term outcomes would further inform clinical decision-making concerning dismissal from therapy.

Assessment of urinary incontinence

1. In the past, nursing practice toward incontinence has focused on urine containment and skin protection rather than on proactive treatment-oriented therapeutic care. 2. Accurate assessment and diagnosis of urinary incontinence determine the success of treatment. 3. Efforts directed at early identification, appropriate assessment and treatment, and linkage to community agencies should be initiated by the nurse.

Speech-language evaluation of closed head injured subjects in South Africa: cultural applicability and ecological validity of a test battery

This paper addresses the communicative outcome of a group of closed head injured (CHI) subjects in South Africa. Communicative outcome is evaluated on one test battery currently used for medico-legal assessments in South Africa. It was found that a number of the tests were sensitive to breakdown in this sample, but that the demographic factors of first language and pre-injury education significantly affected performance on some tests. Many test performances were significantly related to return to work, thus confirming the importance of communicative skills in the workplace, and the speech-language pathologist's role in vocational assessment and rehabilitation.

Binding of plasma fibronectin to Candida albicans occurs through the cell binding domain

Candida albicans yeast cells bind soluble human plasma fibronectin (Fn) through a glycoprotein receptor (adhesin) located on the cell surface. This work demonstrates that a 120 kDa proteolytic fragment of Fn encompassing the cell binding domain binds more avidly to the yeast cell adhesin than does the parent Fn molecule. The presence of binding of Fn fragments containing heparin- and gelatin-binding domains of Fn could not be detected. The binding of the 120 kDa fragment is inhibited by a monoclonal antibody to the cell binding domain containing the amino acid sequence, Arginine-Glycine-Aspartic acid (RGD) as well as by an RGD-containing approximately 23-mer Fn peptide, but not with heparin or GRGDSPL. The fact that the cell binding domain of soluble Fn binds more avidly than does the parent molecule may explain the difference in the interaction of soluble Fn and immobilized Fn with Candida. It is possible that, upon immobilization, Fn may expose domains of the molecule previously unexposed when the molecule is in the soluble state.

Interaction of spirochetes with the host

The success of an invading organism must depend on several cytoplasmic, surface-associated and secreted factors. The technical difficulties in handling pathogenic spirochetes like Treponema pallidum and Borrelia burgdorferi have made it difficult to define specific factors involved in entry and long-term survival. The problem of defining virulence factors has been attacked by several strategies: T. pallidum secretes a number of immunogenic low molecular mass proteins. The most predominant are of molecular weight 15.5 and 22 kDa. Preliminary data suggest that antibodies against these proteins induce protective immunity in rabbits experimentally infected with T. pallidum. Many potentially important surface-associated antigens of T. pallidum have now been cloned and characterized. Two of these, TpD and TpE, are lipoproteins which exhibit characteristic size heterogeneity. The apparent molecular weight of TpE from T. pallidum and T. pertenue are different. The clinical symptoms in syphilis and yaws are very different, but sequence analysis of TpE has shown that the TpE proteins are indeed very similar in the two strains. This observation makes it unlikely that heterogeneity of TpE can account for the different clinical symptoms of syphilis and yaws. Sequence data for another newly sequenced surface-associated antigen of T. pallidum (molecular weight 41 kDa) indicate that this protein is involved in glucose transport and chemotaxis/motility. Intracellular factors like the molecular chaperonin GroEL have been documented both in treponemes and borreliae. This stress protein is involved in cellular repair processes and folding/assembly of protein subunits. Indirect evidence suggests that GroEL affects the ability of spirochetes to survive in the stressful environment of the infected host. Several lines of evidence suggest that the Osp proteins of Borrelia are important for host/parasite interaction. Further support for this idea has come from studies of a series of monoclonal antibodies against OspA. A monoclonal antibody against OspA (9B3D) is able to block attachment of B. burgdorferi to a cell monolayer. Borrelia loses infectivity after several passages in vitro. The loss of pathogenicity is associated with loss of specific plasmids and proteins. One of the low-passage-associated proteins (Lap30) has been cloned and sequenced. Lap30 is a lipoprotein encoded by a 38-kb plasmid, not present in high passage B. burgdorferi. Aberrant immunological processes induced by the lipopolysaccharide component of Treponema hyodysenteriae could explain the dramatic intestinal lesions in swine dysenteriae. But analysis by TLC reveals that the LPS of this treponeme is different from classical Salmonella LPS.(ABSTRACT TRUNCATED AT 400 WORDS)

Discourse therapy in multilingual aphasia: a case study

Analysis of the strategies used in narrative and conversational discourse enables a sensitive evaluation of the deficit in mild aphasic patients and a possible alternative to the therapist dealing with multilingual patients for whom standard aphasia testing is not useful. This study describes the characterization of the communication deficit in a multilingual aphasic patient and the development and subsequent implementation of a therapy programme. Standard testing and discourse analysis took place in four languages, but therapy took place in English. Improvement in conversational skills was noted in all four languages and the patient reported increased functional ability, particularly in a work context. The implications of this approach to assessment and therapy are discussed.

Stable expression of foreign antigens from the chromosome of Salmonella typhimurium vaccine strains

A simple and versatile system has been developed using a new cloning vector which can serve as a vehicle for integrating DNA fragments, which direct the expression of heterologous antigens, into the aroC gene on the Salmonella chromosome. The system is based on Escherichia coli plasmid vectors which contain the DNA fragment, cloned from the chromosome of S. typhimurium C5, which encodes the aroC gene. The aroC gene was modified using synthetic oligodeoxyribonucleotides so that it contained several unique restriction sites into which DNA, directing the expression of heterologous antigens, could be cloned. DNA was integrated into the S. typhimurium chromosome at aroC by transferring the vectors into S. typhimurium polA mutants and allowing homologous recombination to occur between the cloned and chromosomal aroC genes. The vectors were used to integrate nucleotide sequences into the S. typhimurium chromosome which directed the expression of tetanus toxin fragment C and the Treponema pallidum lipoprotein. The expression of both antigens was detected by Western blotting.

Acquired childhood aphasia with convulsive disorder (Landau-Kleffner syndrome). A case report

The Landau-Kleffner syndrome is a rare form of acquired childhood aphasia associated with convulsive disorder. These children are typically misdiagnosed. A 15-year-old girl whose aphasia was not diagnosed until the age of 13 is described. Pitfalls in diagnosis are discussed, particularly with regard to interpretation of the results of audiometric testing. Attention is drawn to the existence of this rare form of aphasia and to the lack of appropriate educational facilities for aphasic children in general.

The role of RNA segment 1 in an in vitro host restriction occurring in an avian influenza virus mutant

A temperature sensitive mutant, ts C47, derived from A/FPV/Rostock/34 and with a ts mutation in RNA segment 8, fails to form plaques in MDCK cells. From data obtained with reassortant viruses using the human influenza isolate A/FM/1/47 it was apparent that more than one mutation contributed to the temperature-sensitive (ts) and host range (hr) phenotypes of ts C47, and the phenotype of reassortants containing RNA segment 1 from A/FM/1/47 indicated that this segment was involved. A single nucleotide substitution at nucleotide 1961, resulting in valine instead of methionine in the predicted amino acid sequence of polypeptide PB2, was found in RNA segment 1 of ts C47, but this mutation did not segregate with the attenuated phenotype on gene reassortment. The following conclusions are drawn: (a) that ts C47 has at least two mutations in addition to that already known to exist in RNA segment 8, one of which (that in RNA segment 1) does not contribute to the observed ts hr phenotypes and (b) that the hr phenotype can be suppressed by substitution of RNA segment 1 by that of another strain.

Identification of the major antigens of Treponema hyodysenteriae and comparison with those of Treponema innocens

Eleven strains of Treponema hyodysenteriae isolated from pigs with swine dysentery were examined by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. T. hyodysenteriae strains formed a homogeneous group with respect to sodium dodecyl sulfate-soluble proteins. However, immunoblotting with antiserum from rabbits immunized with T. hyodysenteriae CN8368 revealed heterogeneity among the lipopolysaccharide complexes of different strains. Polypeptides of molecular weights between 30,000 and 36,000 were the predominant T. hyodysenteriae polypeptides detected by porcine immune serum. In contrast, Treponema innocens did not form a homogeneous group with respect to sodium dodecyl sulfate-soluble proteins. Adsorption studies and immunoblotting identified polypeptide antigens present on cells of T. hyodysenteriae which were not detected on cells of T. innocens. These unique antigens may play a role in the virulence of T. hyodysenteriae.

Compensatory strategies in the language of closed head injured patients

The study reported here examined the nature and effectiveness of compensatory strategies appearing in the conversational discourse of six closed head injured patients. Subject performance on a range of communication measures was compared with their judged abilities on a taxonomy of 32 compensatory strategies. Results indicated that all subjects employed a wide range of strategies but to differential effect. The overall effectiveness of these strategies correlated strongly with performance on the oral language subtest of the Western Aphasia Battery, the Communicative Abilities in Daily Living Test and a pragmatic protocol. The development of compensation following brain injury is viewed as a process of equilibration, determined in part by neurological and subject variables, and in part by ecologic variables. The implications for therapeutic management are discussed.