bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving anaesthetists' communication skills
Authors: Harms C. , Young J. R. , Amsler F. , Zettler C. , Scheidegger D. , Kindler C. H.
Published: January 2004

The attitude, behaviour and communication skills of specialised doctors are increasingly recognised as important and they have been identified as training requirements. We designed a programme to teach communication skills to doctors in a University Department of Anaesthesia and evaluated its effect on patient outcomes such as satisfaction and anxiety. The 20 h programme was based on videotaped reviews of actual pre‐operative visits and role‐playing. Effects on patient satisfaction and pre‐operative anxiety were assessed using a patient questionnaire. In addition, all participating anaesthetists assessed the training. We provide evidence that the training increased patient satisfaction with the pre‐operative anaesthetic visit. Training also decreased anxiety associated with specific aspects of anaesthesia and surgery, but the effect was rather small given the intense programme. The anaesthetists agreed that their interpersonal skills increased and they felt better prepared to understand patients' anxieties. Communication skills training can increase patient satisfaction and decrease specific anxieties. The authors conclude that in order to better demonstrate the efficacy of such a training programme, the particular communication skills of anaesthetists rather than indirect patient outcome parameters should be measured.
Synacthen Depot® for the treatment of postdural puncture headache*
Authors: Rucklidge M. W. M. , Yentis S. M. , Paech M. J.
Published: January 2004

We conducted a prospective, randomised, double‐blind trial to study the effect of Synacthen Depot® in 18 parturients with postdural puncture headache following deliberate or accidental dural puncture. Women were randomly allocated to receive either Synacthen Depot 1 mg (1 ml) or 0.9% saline 1 ml intramuscularly. Using a 10‐cm visual analogue scale, severity of headache was measured before and at intervals until 48 h after injection. There was no difference in the severity of headache or requirement for epidural blood patch. We conclude that there is no advantage to the use of Synacthen Depot 1 mg for the treatment of postdural puncture headache.
Another look at Dumfries
Authors: Martin L. V. H.
Published: January 2004

Following William Morton's demonstration of ether anaesthesia in the Massachusetts General Hospital in October 1846, the first major operation in the Old World is credited to Robert Liston at University College Hospital on 21 December 1846. It has been suggested that a similar operation took place in Dumfries on 19 December 1846. The existing evidence is reviewed and new evidence from newspapers and hospital annual reports is presented. This evidence does not support the Dumfries claim.
Did anything change? Caregivers and schizophrenia after medication changes
Authors: RUDGE T. , MORSE K.
Published: January 2004

This paper reports on a qualitative, critical study into the lives of relatives and partners of people living with enduring effects of schizophrenia. A review of the literature showed that caregivers and relatives of sufferers were seldom asked about their experiences, instead they were subject to blame or criticism regarding their parental or caregiving practices. Caregivers of people with schizophrenia were interviewed in order to reveal their experience of caring for their kin after a medication change to atypical neuroleptics. The interview analysis was compared with mental health professional literature, using a Foucauldian approach to reveal the operation of language and power in the positioning of caregivers. This analysis was then compared to the talk of the caregivers. Similarities and differences in their ways of talking about caring were identified. Caregivers spoke of protracted periods of time before the establishment of a definite diagnosis, ambivalence about medication and ‘never giving up’. The paper concludes that life for caregivers is constituted as doubly problematic, experiencing stigma personally and vicariously through their kin.
Advancing self‐determination with young adults who have schizophrenia
Authors: MCCANN T. V. , CLARK E.
Published: January 2004

The research examined how community mental health nurses promote self‐determination with clients who are experiencing an early episode of schizophrenia. The study used grounded theory methodology incorporating interviews and observations. The study took place in the community, in rural and regional New South Wales, Australia, and involved clients and community mental health nurses. The findings show that the promotion of self‐determination is dependent on nurses educating clients about their illness and well‐being, and fostering self‐control. The development of a reciprocal relationship, or alliance, between nurses and clients is implicit in advancing self‐determination. The implications of the promotion of client self‐determination for education, clinical practice and research and these are discussed.
A Meaningful Day Group approach to weight gain from antipsychotic medication
Authors: O'MELIA J. , SHAW P. , DICKINSON C.
Published: January 2004

For clients who receive medical treatment for a severe and enduring mental health problem, antipsychotic medication is the first line of treatment. The adverse effects of these medications are well documented and can lead to discontinuation of therapy. The newer atypical antipsychotics would seem to have distinct advantages over more traditional substances but significant weight gain can be experienced. This group is an attempt to capitalize upon psychosocial approaches to this such that outcome may be enhanced. The following is a description of an attempt to implement such a group and to explore the outcome. The group has been devised by one of the manufacturers of atypical antipsychotic medication concerned by the side‐effect to their product. The group is formatted on a computer disc ready to use by any mental health professional and freely available.
Evidence‐based uncertainty in mental health nursing
Authors: FRANKS V.
Published: January 2004

The drive towards evidence‐based practice is part of a modern reflective and caring service. However there is a paradox at the heart of the notion of evidence‐based care. In order to perform any systemized examination of treatment there has to be a conscious acknowledgement of uncertainty about that treatment. This is uncomfortable and when research does find evidence in favour of a treatment, there is a relief and a return to conviction about what is the best. The paradox is that it seems the most valued research practices are predicated on generalizations about patient treatments and categories. However, nursing care is based on the notion of the uniqueness of the patient and the nurse–patient relationship. Sometimes it is necessary to address the particular and not to rush to generalizations and certainty. The psychoanalytic framework promotes a capacity to tolerate uncertainty and provides a model for understanding conflicting feelings, which can occur within the nurse–patient relationship. The author proposes the psychoanalytic observational method as an adjunct to other research methods. This method places certain kinds of evidence within the rubric of evidence‐based nursing practice. The evidence collected in this method is the evidence of the conscious and unconscious experience within the nurse–patient relationship. The author will describe and argue for the place of this research method within the canon of other more widely practised methods within mental health practice. She will propose that for safe practice it is necessary to value and examine the veracity of the feelings and tacit understanding of the nurse. She contends that the current climate of excessive bureaucracy and persecutory risk management is having a damaging effect on both the research process and effective nursing care.
Feasibility of open simple prostatectomy with early vascular control
Authors: Shaheen A. , Quinlan D.
Published: February 2004

OBJECTIVE

To determine the feasibility of open simple prostatectomy with early vascular control in the treatment of benign prostate hyperplasia (BPH), and thus reduce blood loss.

PATIENTS AND METHODS

Thirty‐seven patients were reviewed from 1991 to 2002; 34 had a Millin's and three a Freyer's prostatectomy performed by one surgeon, with early vascular control.

RESULTS

The mean operative duration was 1.3 h and the mean blood loss 841 mL, with a mean decrease in haemoglobin level of 22 g/L. Six (16%) of the patients received a blood transfusion. The mean weight of the prostate removed was 97.8 g; the duration of catheterization and the hospital stay after surgery were 6.21 and 11.7 days, respectively. There was one (3%) death and one case of pulmonary embolism. Three patients (8%) developed stress incontinence. Two failed to void after surgery and one developed acute retention 3 years later. Five patients developed recurrent obstructive symptoms.

CONCLUSION

Open simple prostatectomy with early vascular control reduces the amount of blood loss, rendering it a safe option for treating BPH.
Female paraurethral cysts: experience of 25 cases
Authors: Sharifi‐Aghdas F. , Ghaderian N.
Published: February 2004

OBJECTIVE

To report and describe the diagnosis and treatment of female paraurethral cysts.

PATIENTS AND METHODS

Twenty‐five cases of cysts of the external female genitalia were diagnosed over a 7‐year period, using a physical examination, routine blood tests, urine analysis, abdominal ultrasonography and cysto‐urethroscopy in all. The cysts were incised, drained and marsupialized; no attempt was made to excise or remove the internal wall of the cyst and it remained in situ.

RESULTS

All patients responded to simple marsupialization, with no recurrence of the cyst.

CONCLUSION

Cysto‐urethroscopy and a limited laboratory and imaging evaluation were enough for the diagnosis.
A pilot study of use of the cyclooxygenase‐2 inhibitor celecoxib in recurrent prostate cancer after definitive radiation therapy or radical prostatectomy
Authors: Pruthi R.S. , Derksen J.E. , Moore D.
Published: February 2004

OBJECTIVES

To evaluate the efficacy of the cyclooxygenase (COX)‐2 inhibitor celecoxib in prostate‐specific antigen (PSA) recurrent prostate cancer after definitive radiation therapy (RT) or radical prostatectomy (RP), as recent evidence showed that COX‐2 inhibitors have potent antitumour activity in prostate cancer both in vitro and in vivo but there are no human trials.

PATIENTS AND METHODS

Twelve patients who had biochemical relapse after RT or RP were treated with celecoxib 200 mg twice daily. Follow‐up PSA levels to assess efficacy were obtained at 3, 6 and 12 months after initiating treatment. Data were evaluated by calculating PSA doubling times and the slope of the curve of logPSA vs time, to assess rate of PSA rise before and after celecoxib treatment for each patient. Serum testosterone levels were also measured.

RESULTS

Eight of the 12 patients had significant inhibition of their serum PSA levels after 3 months of treatment; five had a decline in their absolute PSA level and three a stabilization of the level. Of the remaining four patients, three had a marked decrease in their PSA doubling time, with a mean increase (i.e. slowing) of 3.1 times that before treatment. The short‐term responses at 3 months also continued at 6 and 12 months. From the slope of log PSA vs time there was a significant flattening of the rate of PSA rise (P = 0.001). There was a significant change of patients with rapid doubling times towards slower doubling times or even stable/declining PSA values after treatment with celecoxib (P = 0.029). There was no significant change in testosterone levels, suggesting an androgen‐independent mechanism.

CONCLUSIONS

COX‐2 inhibitors may have an effect on serum PSA levels in patients with biochemical progression after RT or RP. These results suggest that COX‐2 inhibitors may help to delay or prevent disease progression in these patients, and thereby help extend the time until androgen deprivation therapy. Further study with more patients is currently underway to better evaluate the clinical potential of COX‐2 inhibitors as an antitumour agents in prostate cancer.
Task orientation, parental warmth and SES account for a significant proportion of the shared environmental variance in general cognitive ability in early childhood: evidence from a twin study
Authors: Petrill Stephen A. , Deater‐Deckard Kirby
Published: January 2004

Prior research suggests shared environmental influences on cognitive performance are important in early childhood. However, few studies have attempted to identify the factors comprising this shared environmental variance. To address this issue, we examined the covariance between task orientation, parental warmth, socioeconomic status and general cognitive ability in a British twin study of 125 pairs of identical and same‐sex fraternal twins. Task orientation correlated r = .41 with general cognitive ability. Bivariate genetic analyses suggested that this correlation was mediated by shared environmental influences. Additional analyses suggested that SES and parental warmth mediated about two‐thirds of the shared environmental covariance between task engagement and cognitive skills.
Reorganization in coping behavior at 1½ years: dynamic systems and normative change
Authors: Lewis Marc D. , Zimmerman Sara , Hollenstein Tom , Lamey Alex V.
Published: January 2004

By the age of 1 year toddlers demonstrate distinct coping habits for dealing with frustration. However, these habits may be open to change and reorganization at subsequent developmental junctures. We investigated change in coping habits at 18–20 months, a normative age for major advances in social cognition, focusing on the dynamic systems principles of fluctuation and novelty at transitions. Specifically, we asked whether month‐to‐month fluctuation, novel behavioral habits and real‐time variability increased at the age of a normative transition, despite individual differences in the content of behavior. Infants were given frustrating toys while their mothers sat nearby without helping, on monthly visits at 14–25 months (before, during and after the hypothesized transition). State space grids representing patterns of behavioral durations were constructed for each episode and compared over age. As predicted, month‐to‐month fluctuation in grid patterns increased temporarily between 17 and 20 months, partly independently of a concurrent peak in distress, and new behavioral habits replaced old ones at the same age. Coping habits changed differently for high‐ and low‐distressed toddlers. However, changes in real‐time variability did not generally meet our expectations.
Evaluating the Business Case for Part‐time Working amongst Qualified Nurses
Authors: Edwards Christine , Robinson Olive
Published: January 2004

A ‘new’ business case for part‐time working assumes a mutuality of benefit for employer and employees. Examining this hypothesis from the perspective of qualified nursing staff and managers in the NHS, a context in which the new business case for part‐time working is particularly strong, this study found that the full benefits are not realized for either side. Extending the findings of other research into highly skilled/professional occupations, we conclude that, without substantive change in systems of work, the expansion of the part‐time work‐force could entail the under‐utilization of the skills of an indispensable section of the working population.
The Relations of Effortful Control and Impulsivity to Children's Resiliency and Adjustment
Authors: Eisenberg Nancy , Spinrad Tracy L. , Fabes Richard A. , Reiser Mark , Cumberland Amanda , Shepard Stephanie A. , Valiente Carlos , Losoya Sandra H. , Guthrie Ivanna K. , Thompson Marilyn
Published: February 2004

The unique relations of effortful control and impulsivity to resiliency and adjustment were examined when children were 4.5 to 8 years old, and 2 years later. Parents and teachers reported on all constructs and children's attentional persistence was observed. In concurrent structural equation models, effortful control and impulsivity uniquely and directly predicted resiliency and externalizing problems and indirectly predicted internalizing problems (through resiliency). Teacher‐reported anger moderated the relations of effortful control and impulsivity to externalizing problems. In the longitudinal model, all relations held at T2 except for the path from impulsivity to externalizing problems. Evidence of bidirectional effects also was obtained. The results indicate that effortful control and impulsivity are distinct constructs with some unique prediction of resiliency and adjustment.
Child Care in Poor Communities: Early Learning Effects of Type, Quality, and Stability
Authors: Loeb Susanna , Fuller Bruce , Kagan Sharon Lynn , Carrol Bidemi
Published: February 2004

Young children in poor communities are spending more hours in nonparental care because of policy reforms and expansion of early childhood programs. Studies show positive effects of high‐quality center‐based care on children's cognitive growth. Yet, little is known about the effects of center care typically available in poor communities or the effects of home‐based care. Using a sample of children who were between 12 and 42 months when their mothers entered welfare‐to‐work programs, this paper finds positive cognitive effects for children in center care. Children also display stronger cognitive growth when caregivers are more sensitive and responsive, and stronger social development when providers have education beyond high school. Children in family child care homes show more behavioral problems but no cognitive differences.
From Censure to Reinforcement: Developmental Changes in the Association Between Aggression and Social Status
Authors: Cillessen Antonius H. N. , Mayeux Lara
Published: February 2004

Developmental changes were examined in the associations among physical and relational aggression, and sociometric and perceived popularity based on peer nominations. Participating in the longitudinal study were 905 children (440 girls, 465 boys) from ages 10 to 14. Associations between the forms of status and between the forms of aggression decreased over time. Relational aggression increasingly predicted high social prominence but low social preference; physical aggression was increasingly less disliked but decreasingly predictive of prominence. The effect of relational aggression on perceived popularity was strong for girls. Perceived popularity preceded physical and relational aggression for both genders. Implications for the attainment of high status, processes of peer influence on antisocial behavior, and gender differences in the meaning of status are discussed.
Linked Lives: Stability and Change in Maternal Circumstances and Trajectories of Antisocial Behavior in Children
Authors: Macmillan Ross , McMorris Barbara J. , Kruttschnitt Candace
Published: February 2004

Drawing on the notion of linked lives, this study examined the effects of stability and change in maternal circumstance on developmental trajectories of antisocial behavior in children 4 to 7 years of age. Using data from a national sample of young mothers and growth curve analysis, the study demonstrated that early maternal circumstances influences early antisocial behavior, whereas stability and change in these circumstances both exacerbate and ameliorate behavior problems. Of particular note, meaningful escape from poverty attenuates antisocial behavior whereas persistence in poverty or long‐term movement into poverty intensifies such problems. These findings highlight the importance of structural context for parenting practices and the need to consider child development in light of dynamic and changing life‐course fortunes of parents.
Social Norms and Private Provision of Public Goods
Authors: Rege Mari
Published: January 2004

The formation of social norms for voluntary contributions to a public good is analyzed in a game in which people have preferences for private consumption, a public good, and social approval. Each person chooses to be one of the two types: a contributor or a non‐contributor. Thereafter, each person meets people who can observe his type. A non‐contributor feels disapproval, whereas a contributor feels approval if he believes that a contributor observes his type. The game has two asymptotically stable states: one in which everybody is a contributor, and one in which nobody is a contributor. Governmental subsidization of the public good can move the society to the former state, whereas a governmental contribution to the public good can move the society to the latter. Indeed, this crowding in or crowding out prevails even after policy reversal.
Revoicing Silenced Sirens: A Changing Motif in Works by Franz Kafka, Frank Wedekind and Barbara Köhler
Authors: Boa Elizabeth
Published: January 2004

The episode of Odysseus’ encounter with the Sirens in Horkheimer's and Adorno's Dialektik der Aufklärung follows on a long history of images of Sirens and other water‐women in modernist literature which proliferated around the turn of the nineteenth to the twentieth century, when masculine and feminine roles were hotly contested under the impact of rapid social change and of the first feminist movement. At issue here is a shift in this discourse from uncannily demonic figures towards travesty in two modernist writers, Wedekind and Kafka. Whereas the uncanny erotic force of the demonic feminine remains strong in Wedekind's Lulu plays and in the figure of Leni in Der Proceß, a cynical or parodic tendency increases in later work. Common to Kafka's ‘Das Schweigen der Sirenen’ and Wedekind's Der Kammersänger is the silencing of the Sirens as the uncanny modulates into travesty, a shift reflecting the authors’ growing sense of their collusion in a culture which was oppressive to women, yet at the same time an inability to break free from the prevailing gender ideology. In both texts the Sirens lose their song, which is appropriated to fuel the supposedly androgynous creativity of the male artist. Barbara Köhler, by contrast, revoices the Sirens in her poem ‘(Sirenen 2)’. This achieves an interpenetrating and fluid unity which yet is controlled by the technology of print, by witty play on words and through a sophisticated game of intertextual allusion. ‘(Sirenen 2)’ offers an assured, eloquent revoicing of the Sirens for our time.
Christa Wolf's Kassandra and Medea: Continuity and Change
Authors: Bridge Helen
Published: January 2004

When Christa Wolf's Medea: Stimmen appeared in 1996, some critics accused the work of being little more than a pale repetition of the earlier Kassandra project. This paper argues that, while broad continuities in Wolf's concerns are obvious, the shift from monologue in Kassandra to a polyphony of voices in Medea is symptomatic of subtle, yet important shifts in her approach to myth and her understanding of history. Although Wolf's archaeological understanding of myth and the problems this raises remain unchanged, the focus has shifted from the effects myth has on the individual to the human needs which give rise to it. The more psychological exploration of myth in Medea reveals interesting shifts in Wolf's understanding of the individual's role in history. In Kassandra, just as we assume that individuals exercise sovereign control over the myths they circulate, so we have the impression that history results from human agency in accordance with the will of those in power. In Medea, Wolf seems more doubtful about the ability of individuals to control events, even those they have caused. The idea of a coherent historical development, albeit a negative one, which is central to the Kassandra project, is absent from the later work.
Trade union shopfloor representation in Germany
Authors: Klikauer Thomas
Published: January 2004

Most publications on German industrial relations tend to focus on works councils but miss trade union delegates and senior delegates. Seeking to address this lack of research, a case study of a large manufacturing plant is used to examine the role of union delegates and senior delegates and their relationship to works councils. The case study seeks to show why works councils are inextricably linked to the union movement, even though both are structurally separated. Research findings support the notion that both are in a mutually supportive relationship. Furthermore, the evidence also suggests that trade union shopfloor representation is of crucial importance for works councils, industrial democracy and trade unions in German industrial relations.
Career priorities within dual career households: an analysis of the impact of child rearing upon gender participation rates and earnings
Authors: Hardill Irene , Watson Robert
Published: January 2004

The impact of child rearing upon male and female participation rates and earnings within 130 dual career households is investigated. Female participation rates and earnings in households with children are significantly lower than both comparable males and females without children. No significant gender differences exist in pay in childless households.
Should Intangibles Be Measured: What Are the Economic Trade‐Offs?
Authors: KANODIA CHANDRA , SAPRA HARESH , VENUGOPALAN RAGHU
Published: February 2004

We investigate whether a firm's intangible investments should be measured and separated from operating expenses. We find that the information extracted from accounting reports of investments and earnings is different when intangibles are measured and identified separately from operating expenses than when intangibles are left commingled with operating expenses. This difference in the market's information causes a change in the behavior of market prices, inducing changes in the firm's investments and cash flows. Thus, from a real effects perspective, measuring intangibles is not unambiguously desirable. We identify the conditions under which providing information on intangibles may be desirable. This study also shows the inadequacy of statistical associations between accounting numbers and prices as a basis for evaluating the desirability of measuring intangible investments. We show that the measurement of intangibles alters the very distribution of cash flows about which the measurement regime is seeking to provide information.
Peripubertal Girls' Romantic and Platonic Involvement With Boys: Associations With Body Image and Depression Symptoms
Authors: Compian Laura , Gowen L. Kris , Hayward Chris
Published: February 2004

This study explored the relationship of both romantic and platonic involvement with boys, as well as pubertal status, to body image and depression symptoms among an ethnically diverse sample of sixth‐grade girls. Participants were 157 early adolescent girls (ages 10–13) who completed self‐report measures designed to assess girls' level of involvement with boys, pubertal status, and psychological adjustment. Girls' degree of romantic involvement was positively associated with higher depression scores. More advanced pubertal status was associated with both lower body image satisfaction and higher depression scores. A significant interaction between platonic involvement and pubertal status emerged. Girls who were less sexually mature but who also reported more platonic involvement with boys reported greater body image satisfaction. These findings suggest that the type of involvement with boys (romantic vs. platonic) and a girl's pubertal status influence psychological adjustment.
Interactive Instruction on Ideal and “Real” Gases
Authors: Ringlein James
Published: January 2004

This article explores efforts to use simulation software in conjunction with peer instruction techniques toward improving student comprehension of particle interactions in ideal and “real” gases. A series of Interactive Physics™ simulations builds group student inquiry from small-scale ideal gas cases through larger, more realistic particle simulations. The mathematics associated with the simulations is intentionally minimized in order to focus student attention on conceptual understanding. References are made to other efforts in this educational direction, both in terms of rationale and applications. A website is cited in the Notes section containing both movie versions of the simulations, and includes the files available for download by IP users.
Current Concepts Consolidated
Authors: Rehfuss Donald E.
Published: January 2004

Many instructors use conceptual analogies between water pipes and electrical circuits, but the isomorphism of related transport equations is not as commonly appreciated. The Laws of Fourier, Ohm, and Poiseuille may all be cast into nearly identical forms for flows of heat, electric charges, and viscous fluids, respectively. Examining such formal similarities may enhance student understanding.
The Poynting-Robertson Effect
Authors: Binder P.-M. , Iaukea-Lum Miki , Purves Norman G.
Published: January 2004

The purpose of this article is to present a simple apparatus for demonstrating the Poynting-Robertson (PR) effect, which is of interest in planetary astronomy. Our setup involves linear rather than rotational motion, and only needs the standard air-track apparatus that is commonly used in freshman labs to verify conservation of linear momentum.
Formation of Thiolated Nucleosides Present in tRNA from
Salmonella enterica
serovar Typhimurium Occurs in Two Principally Distinct Pathways
Authors: Leipuviene Ramune , Qian Qiang , Björk Glenn R.
Published: January 2004

tRNA from
Salmonella enterica
serovar Typhimurium contains five thiolated nucleosides, 2-thiocytidine (s
2
C), 4-thiouridine (s
4
U), 5-methylaminomethyl-2-thiouridine (mnm
5
s
2
U), 5-carboxymethylaminomethyl-2-thiouridine (cmnm
5
s
2
U), and
N
-6-(4-hydroxyisopentenyl)-2-methylthioadenosine (ms
2
io
6
A). The levels of all of them are significantly reduced in cells with a mutated
iscS
gene, which encodes the cysteine desulfurase IscS, a member of the ISC machinery that is responsible for [Fe-S] cluster formation in proteins. A mutant (
iscU52
) was isolated that carried an amino acid substitution (S107T) in the IscU protein, which functions as a major scaffold in the formation of [Fe-S] clusters. In contrast to the
iscS
mutant, the
iscU52
mutant showed reduced levels of only two of the thiolated nucleosides, ms
2
io
6
A (10-fold) and s
2
C (more than 2-fold). Deletions of the
iscU
,
hscA
, or
fdx
genes from the
isc
operon lead to a similar tRNA thiolation pattern to that seen for the
iscU52
mutant. Unexpectedly, deletion of the
iscA
gene, coding for an alternative scaffold protein for the [Fe-S] clusters, showed a novel tRNA thiolation pattern, where the synthesis of only one thiolated nucleoside, ms
2
io
6
A, was decreased twofold. Based on our results, we suggest two principal distinct routes for thiolation of tRNA: (i) a direct sulfur transfer from IscS to the tRNA modifying enzymes ThiI and MnmA, which form s
4
U and the s
2
U moiety of (c)mnm
5
s
2
U, respectively; and (ii) an involvement of [Fe-S] proteins (an unidentified enzyme in the synthesis of s
2
C and MiaB in the synthesis of ms
2
io
6
A) in the transfer of sulfur to the tRNA.
Direct Glutaminyl-tRNA Biosynthesis and Indirect Asparaginyl-tRNA Biosynthesis in
Pseudomonas aeruginosa
PAO1
Authors: Akochy Pierre-Marie , Bernard Dominic , Roy Paul H. , Lapointe Jacques
Published: January 2004

The genomic sequence of
Pseudomonas aeruginosa
PAO1 was searched for the presence of open reading frames (ORFs) encoding enzymes potentially involved in the formation of Gln-tRNA and of Asn-tRNA. We found ORFs similar to known glutamyl-tRNA synthetases (GluRS), glutaminyl-tRNA synthetases (GlnRS), aspartyl-tRNA synthetases (AspRS), and trimeric tRNA-dependent amidotransferases (AdT) but none similar to known asparaginyl-tRNA synthetases (AsnRS). The absence of AsnRS was confirmed by biochemical tests with crude and fractionated extracts of
P. aeruginosa
PAO1, with the homologous tRNA as the substrate. The characterization of GluRS, AspRS, and AdT overproduced from their cloned genes in
P. aeruginosa
and purified to homogeneity revealed that GluRS is discriminating in the sense that it does not glutamylate tRNA
Gln
, that AspRS is nondiscriminating, and that its Asp-tRNA
Asn
product is transamidated by AdT. On the other hand, tRNA
Gln
is directly glutaminylated by GlnRS. These results show that
P. aeruginosa
PAO1 is the first organism known to synthesize Asn-tRNA via the indirect pathway and to synthesize Gln-tRNA via the direct pathway. The essential role of AdT in the formation of Asn-tRNA in
P. aeruginosa
and the absence of a similar activity in the cytoplasm of eukaryotic cells identifies AdT as a potential target for antibiotics to be designed against this human pathogen. Such novel antibiotics could be active against other multidrug-resistant gram-negative pathogens such as
Burkholderia
and
Neisseria
as well as all pathogenic gram-positive bacteria.
Regulation of Transcription of Compatible Solute Transporters by the General Stress Sigma Factor, σB, inListeria monocytogenes
Authors: Cetin Mehmet Sevket , Zhang Chaomei , Hutkins Robert W. , Benson Andrew K.
Published: January 2004

Listeria monocytogenesis well known for its durable physiological characteristics, which allow the organism to grow at low temperature and pH and high osmolarity. Growth under high osmolarity depends on the accumulation of compatible solutes, among which glycine betaine and carnitine are the preferred solutes for this organism. Three different transport systems, Gbu, BetL, and OpuC, have been identified inL. monocytogeneswhich serve to scavenge the preferred compatible solutes. The general stress response regulator σBhas been shown to play an important role in osmotic adaptation inL. monocytogenes, presumably by directing transcription from one or more of the solute transport genes. In the studies presented here, we have used primer extension analyses to identify the promoter elements responsible for transcription of theopuC,gbuA, andbetLgenes. All three genes are osmotically inducible to some degree.betLis transcribed from a σB-independent promoter, whilegbuAis transcribed from dual promoters, one of which is σBdependent.opuCis transcribed exclusively from a σB-dependent promoter. ThebetLpromoter is similar in sequence to the σB-independentgbuAP1 promoter. Kinetic analysis of transcript accumulation after osmotic upshift demonstrated that σB-dependent transcripts fromgbuAP2 andsigBaccumulate for an extended period after upshift, suggesting that σBactivity may provide a mechanism for sustained high-level expression during osmotic challenge. In contrast to osmotic upshift, expression from the σB-dependentopuCandgbuAP2 promoters after temperature upshift and ethanol stress was minimal, suggesting that additional mechanisms may also participate in regulating transcription from these σB-dependent promoters.
Transferrin-Binding Protein B of
Neisseria meningitidis
: Sequence-Based Identification of the Transferrin-Binding Site Confirmed by Site-Directed Mutagenesis
Authors: Renauld-Mongénie Geneviève , Lins Laurence , Krell Tino , Laffly Laure , Mignon Michèle , Dupuy Monique , Delrue Rose-May , Guinet-Morlot Françoise , Brasseur Robert , Lissolo Ling
Published: January 2004

A sequence-based prediction method was employed to identify three ligand-binding domains in transferrin-binding protein B (TbpB) of
Neisseria meningitidis
strain B16B6. Site-directed mutagenesis of residues located in these domains has led to the identification of two domains, amino acids 53 to 57 and 240 to 245, which are involved in binding to human transferrin (htf). These two domains are conserved in an alignment of different TbpB sequences from
N. meningitidis
and
Neisseria gonorrhoeae
, indicating a general functional role of the domains. Western blot analysis and BIAcore and isothermal titration calorimetry experiments demonstrated that site-directed mutations in both binding domains led to a decrease or abolition of htf binding. Analysis of mutated proteins by circular dichroism did not provide any evidence for structural alterations due to the amino acid replacements. The TbpB mutant R243N was devoid of any htf-binding activity, and antibodies elicited by the mutant showed strong bactericidal activity against the homologous strain, as well as against several heterologous
tbpB
isotype I strains.
Four Novel Genes Required for Optimal Photoautotrophic Growth of the Cyanobacterium
Synechocystis
sp. Strain PCC 6803 Identified by In Vitro Transposon Mutagenesis
Authors: Zhang Shulu , Laborde Susan M. , Frankel Laurie K. , Bricker Terry M.
Published: January 2004

Four novel
Synechocystis
sp. strain PCC 6803 genes (
sll1495
,
sll0804
,
slr1306
, and
slr1125
) which encode hypothetical proteins were determined by transposon mutagenesis to be required for optimal photoautotrophic growth. Mutations were also recovered in
ccmK4
, a carboxysome coat protein homologue, and
me
, the decarboxylating NADP
+
-dependent malic enzyme. This is the first report that these known genes are required for optimal photoautotrophy.
Motility of Urease-Deficient Derivatives of
Helicobacter pylori
Authors: Tan Shumin , Berg Douglas E.
Published: January 2004

Early studies of a
ureB
mutant derivative of
Helicobacter pylori
had suggested that urease is needed for motility and that urease action helps energize flagellar rotation. Here we report experiments showing that motility is unaffected by deletion of
ureA
and
ureB
(urease genes) or by inactivation of
ureB
alone, especially if
H. pylori
strains used as recipients for transformation with mutant alleles are preselected for motility. This result was obtained with the strain used in the early studies (CPY3401) and also with 15 other strains, 3 of which can colonize mice. We conclude that urease is not needed for
H. pylori
motility.
Transcriptional and Posttranscriptional Control of Cable Pilus Gene Expression in
Burkholderia cenocepacia
Authors: Tomich Mladen , Mohr Christian D.
Published: February 2004

Burkholderia cenocepacia
is an important member of the
Burkholderia cepacia
complex, a group of closely related bacteria that inhabits a wide variety of environmental niches in nature and that also colonizes the lungs of compromised humans. Certain strains of
B. cenocepacia
express peritrichous adherence organelles known as cable pili, thought to be important in the colonization of the lower respiratory tract. The genetic locus required for cable pilus biogenesis is comprised of at least five genes, designated
cblB
,
cblA
,
cblC
,
cblD
, and
cblS
. In this study a transcriptional analysis of
cbl
gene expression was undertaken. The principal promoter, located upstream of the
cbl
locus, was identified and characterized. By using
lacZ
transcriptional fusions, the effects of multiple environmental cues on
cbl
gene expression were examined. High osmolarity, temperature of 37°C, acidic pH, and low iron bioavailability were found to induce
cbl
gene expression. Northern hybridization analysis of the
cbl
locus identified a single, stable transcript corresponding to
cblA
, encoding the major pilin subunit. Transcriptional fusion studies combined with reverse transcription-PCR analysis indicated that the stable
cblA
transcript is the product of an mRNA processing event. This event may ensure high levels of expression of the major pilin, relative to other components of the assembly pathway. Our findings lend further insight into the control of cable pilus biogenesis in
B. cenocepacia
and provide evidence for regulation of
cbl
gene expression on both the transcriptional and posttranscriptional levels.
Proteomic Analysis of the Sarcosine-Insoluble Outer Membrane Fraction ofHelicobacter pyloriStrain 26695
Authors: Baik Seung-Chul , Kim Kyung-Mi , Song Su-Min , Kim Do-Su , Jun Jin-Su , Lee Seung-Gyu , Song Jae-Young , Park Jeong-Uck , Kang Hyung-Lyun , Lee Woo-Kon , Cho Myung-Je , Youn Hee-Shang , Ko Gyung-Hyuck , Rhee Kwang-Ho
Published: February 2004

Helicobacter pyloricauses gastroduodenal disease, which is mediated in part by its outer membrane proteins (OMPs). To identify OMPs ofH. pyloristrain 26695, we performed a proteomic analysis. A sarcosine-insoluble outer membrane fraction was resolved by two-dimensional electrophoresis with immobilized pH gradient strips. Most of the protein spots, with molecular masses of 10 to 100 kDa, were visible on the gel in the alkaline pI regions (6.0 to 10.0). The proteome of the OMPs was analyzed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. Of the 80 protein spots processed, 62 spots were identified; they represented 35 genes, including 16 kinds of OMP. Moreover, we identified 9 immunoreactive proteins by immunoblot analysis. This study contributes to the characterization of theH. pyloristrain 26695 proteome and may help to further elucidate the biological function ofH. pyloriOMPs and the pathogenesis ofH. pyloriinfection.
β2-Microglobulin knockout mice treated with anti-asialoGM1 exhibit improved hemodynamics and cardiac contractile function during acute intra-abdominal sepsis
Authors: Tao Weike , Sherwood Edward R.
Published: February 2004

We previously showed that β2-microglobulin knockout mice treated with anti-asialoGM1 (β2M/αAsGM1 mice) exhibit less hypothermia, reduced production of proinflammatory cytokines, less metabolic acidosis, and improved survival after cecal ligation and puncture (CLP) compared with wild-type mice. The present study was designed to assess hemodynamics and left ventricular contractility at 18 h after CLP. Arterial pressure was measured by carotid artery cannulation, and left ventricular pressure-volume loops were obtained by insertion of a 1.4-F conductance catheter into the left ventricle. Heart rate, stroke volume, and cardiac output were not significantly different between wild-type and β2M/αAsGM1 mice after CLP. However, β2M/αAsGM1 mice exhibited improved mean arterial pressure and systemic vascular resistance compared with wild-type mice. Myocardial function was also better preserved in β2M/αAsGM1 mice as indicated by improved left ventricular pressure development over time, time-varying maximum elastance, endsystolic pressure-volume relationship, and preload recruitable stroke work. Overall, this study shows that cardiovascular collapse characterized by hypotension, myocardial depression, and low systemic vascular resistance occurs after CLP in wild-type mice. However, β2M/αAsGM1 mice exhibit improved hemodynamics and cardiac contractile function after CLP that may account, in part, for our previously observed survival benefit.
The Role of Execution Noise in Movement Variability
Authors: van Beers Robert J. , Haggard Patrick , Wolpert Daniel M.
Published: February 2004

The origin of variability in goal-directed movements is not well understood. Variability can originate from several neural processes such as target localization, movement planning, and movement execution. Here we examine variability resulting from noise in movement execution. In several experiments, subjects moved their unseen hand to visual targets, under conditions which were designed to minimize the variability expected from localization and planning processes. We tested short movements in 32 directions in a center-out reaching task. The variability in the movement endpoints and in the initial movement direction varied systematically with the movement direction, with some directions having up to twice the variability of others. In a second experiment we tested four movements in the same direction but with different extents. Here, the longer movements were systematically curved, and the endpoint ellipses were not aligned with the straight line between starting and end position, but they were roughly aligned with the last part of the trajectory. We show that the variability observed in these experiments cannot be explained by planning noise but is well explained by noise in movement execution. A combination of both signal-dependent and signal-independent noise in the amplitude of the motor commands and temporal noise in their duration can explain the observed variability. Our results suggest that, in general, execution noise accounts for at least a large proportion of movement variability.
Neural Circuit of Tail-Elicited Siphon Withdrawal inAplysia.I. Differential Lateralization of Sensitization and Dishabituation
Authors: Bristol Adam S. , Sutton Michael A. , Carew Thomas J.
Published: February 2004

The tail-elicited siphon withdrawal reflex (TSW) has been a useful preparation in which to study learning and memory in Aplysia. However, comparatively little is known about the neural circuitry that translates tail sensory input (via the P9 nerves to the pleural ganglion) to final reflex output by siphon motor neurons (MNs) in the abdominal ganglion. To address this question, we examined the functional architecture of the TSW circuit by selectively severing nerves of semi-intact preparations and recording either tail-evoked responses in the siphon MNs or measuring siphon withdrawal responses directly. We found that the neural circuit underlying TSW is functionally lateralized. We next tested whether the expression of learning in the TSW reflects the underlying circuit architecture and shows side-specificity. We tested behavioral and physiological correlates of three forms of learning: sensitization, habituation, and dishabituation. Consistent with the circuit architecture, we found that sensitization and habituation of TSW are expressed in a side-specific manner. Unexpectedly, we found that dishabituation was expressed bilaterally, suggesting that a modulatory pathway bridges the two (ipsilateral) input pathways of the circuit, but this path is only revealed for a specific form of learning, dishabituation. These results suggest that the effects of a descending modulatory signal are differentially “gated” during sensitization and dishabituation.
Neural Circuit of Tail-Elicited Siphon Withdrawal inAplysia.II. Role of Gated Inhibition in Differential Lateralization of Sensitization and Dishabituation
Authors: Bristol Adam S. , Marinesco Stéphane , Carew Thomas J.
Published: February 2004

In the preceding report, we observed that tail-shock-induced sensitization of tail-elicited siphon withdrawal reflex (TSW) of Aplysia was expressed ipsilaterally but that dishabituation induced by an identical tail shock was expressed bilaterally. Here we examined the mechanisms of this differential lateralization. We first isolated the modulatory pathway responsible for the induction of contralateral dishabituation by making selective nerve cuts. We found that an intact pleural-abdominal connective, the descending pathway connecting the ring ganglia with the abdominal ganglion, ipsilateral to the shock was required for contralateral dishabituation. We examined whether network inhibition suppresses the contralateral effects of tail shock in nonhabituated preparations. We found that blockade of inhibitory transmission in the CNS by the nicotinic ACh inhibitor d-tubocurarine (d-TC) rendered tail shock capable of inducing bilateral sensitization. We next asked whether serotonin (5-HT), a neuromodulator released in the CNS in response to tail shock, was affected by d-TC. We found that d-TC does not alter 5-HT processes in the ring ganglia: it had no effect on the lateralized pattern of tail nerve shock-induced changes in tail sensory neuron excitability, a 5-HT-dependent process, and it did not alter tail nerve shock-evoked release of 5-HT. By contrast, d-TC enhanced 5-HT release in the abdominal ganglion. Consistent with this observation, restricting d-TC to the abdominal ganglion rendered tail nerve shock capable of producing bilateral sensitization. Together with the results of the preceding paper, our results suggest a model in which TSW sensitization and dishabituation can be dissociated both anatomically and mechanistically.