bluuebunny/crossref_metadata_2025 huggingface dataset:
Negotiating Couplehood: The Process of Resolving the December Dilemma among Interfaith Couples
Authors: HOROWITZ JUNE ANDREWS
Published: July 2004

Christmas forces interfaith couples to address questions concerning holiday observances. The purpose of this investigation was to explore the experience of the “December dilemma,” that is, the experience of Christmas and Hanukah among couples in which one partner is Jewish. A qualitative design based on the continuous comparison method of Grounded Theory analysis was used. Participants were solicited through interfaith couples' programs, referral, and snowballing. Unstructured interactive interviews of 22 couples were audiotaped, transcribed, and analyzed. The categories generated were: Ghosts of Christmas and Hanukah Past, Coming Together, and Holiday Observances as a Couple. The basic problem facing these couples was how to bridge religious backgrounds with differing holiday traditions in a way that integrated respect for each partner's needs, heritage, and identity. The basic social process of negotiating “couplehood,” that is, moving from individuality to partnership emerged when mutual agreement could be reached to solve problems about how to celebrate the December holidays. The data indicated that exploration of the ways these couples managed the dilemmas created by the December holidays provided a window to how they negotiated other challenges in their relationships.
Beyond Different Worlds: A “Postgender” Approach to Relational Development
Authors: KNUDSON‐MARTIN CARMEN , MAHONEY ANNE RANKIN
Published: July 2004

Approaches to gender in therapy either reinforce or challenge existing gender differences and inequalities. The authors suggest a way to help clients move beyond gender constructions from the past. They argue that perceived gender differences are rooted in power differences that limit relational development for both women and men, and perpetuate unequal relationship structures. As an alternative to the “two different worlds,” gender‐as‐culture framework, they present an approach to therapy based on an expanded version of Bowen's notion of differentiation. The article helps therapists recognize four “gender traps” that interfere with relational development and suggests strategies for helping clients differentiate from old gender patterns.
Relationships among Parental Reports of Child, Parent, and Family Functioning
Authors: KINSMAN ANNE M. , WILDMAN BETH G. , SMUCKER WILLIAM D.
Published: July 2004

Most children with psychosocial problems do not present for treatment in mental health settings. They are managed by primary care physicians. Children with psychosocial problems often have parents and/or families with psychosocial distress. The present study measured associations between parental reports of child, parent, and family functioning in individuals in the general population. Participants were 226 parents of children, aged 2–16 years, who presented for routine primary care. Parents reported on the psychosocial functioning of themselves, their child, and their family. All correlations of measures were significant, ranging from .55 to .23. Similar to data from psychiatric samples, the psychological functioning of children, parents, and families were significantly correlated. Unlike in psychiatric settings, child mental health problems were not as closely related to parent or family distress as parent and family distress were related to each other and to child behavior problems.
Disruption and Reconstruction: Narrative Insights into the Experience of Family Members Caring for a Relative Diagnosed with Serious Mental Illness
Authors: STERN SERGIO , DOOLAN MOIRA , STAPLES EMMA , SZMUKLER GEORGE L. , EISLER IVAN
Published: July 2004

The findings of a study investigating carers' accounts about serious mental illness occurring in their family are presented. The narrative form is a primary means of ordering, structuring, and communicating illness experiences, reflecting some of the processes that carers intend to master and understand. Psychotic episodes entail a frightening disruption that forces carers to face fundamental existential, moral, and psychological issues because they call into question the continuity of lives and life‐projects. This study has explored how carers articulate the consequences of a devastating experience and turn it into a meaningful event that can in some way be incorporated into the course of their life. Two types of narrative structure were identified. In stories of restitution or reparation, the experience of the event is transformed into phenomena having meaning, occupying a place in carers' lives. In chaotic and frozen narratives, the illness remains a series of random events. The effects on coping of these two narrative types were explored, as well as gender‐related themes and beliefs about mastery and control. Therapeutic implications are discussed and also possible connections to other research constructs (for example, Expressed Emotion). It is argued that the concept of illness must be approached from a systemic, multidetermined perspective that includes our narrative constructions.
Dialectical Behavior Therapy ‐ Family Skills Training
Authors: HOFFMAN PERRY D. , FRUZZETTI ALAN , SWENSON CHARLES
Published: July 2004

Over the past three decades, family interventions have become important components of treatment for a number of psychiatric disorders. To date, however, there has been no family treatment designed specifically for borderline personality disorder patients and their relatives. This article describes one short‐term family intervention called Dialectical Behavior Therapy‐Family Skills Training. Based on Linehan's Dialectical Behavior Therapy (DBT), borderline patients' behavioral patterns are thought to result from a lifelong transaction between emotional vulnerability and invalidating features of the social and familial environment. Individual DBT focuses on reducing individual emotion dysregulation and vulnerability and enhancing individual stability. The complementary family interventions proposed in this article aim to: 1) provide all family members an understanding of borderline behavioral patterns in a clear, nonjudgmental way; 2) enhance the contributions of all family members to a mutually validating environment; and 3) address all family members' emotion regulation and interpersonal skills deficits.
Reconstructing the Brothers Grimm: New Tales for Stepfamily Life
Authors: BERNSTEIN ANNE C.
Published: July 2004

Stepfamilies are situated within the sociopolitical context of family change and are examined as a prototype of the “postmodern” family. This essay looks at the cultural construction of stepfamily life and proposes a model for collaboratively reconstructing stories that liberate step‐relationships from the legacy of the Brothers Grimm, deconstructing the stories of failure, insufficiency, and neglect. Building on narrative and social constructionist ways of thinking about families, the concept of sideshadowing (a hermeneutic approach from literary/historical criticism) is introduced to elucidate how therapists can help family members discover ways of thinking, feeling, and behaving that are both more personally satisfying and more congruent with the changed context of family life. Two therapeutic challenges are highlighted: reconceptualizing what it means to be a stepfamily and coming to terms with differential attachment in relationships while working with stepfamilies. The essay ends with a fairy tale for the 21st century.
Attitudes toward and Perceived Psychosocial Impact of Female Circumcision as Practiced among the Bedouin‐Arabs of the Negev
Authors: AL‐KRENAWI ALEAN , WIESEL‐LEV RACHEL
Published: July 2004

The present pilot study examines attitudes toward and the perceived psychosocial impact of circumcision as practiced among the Bedouin‐Arabs of the Negev, Israel. A convenience sample of 24 women participated in the study: 12 who had experienced the ritual, and 12 who had not, but who had witnessed or been told about the practice of the ritual on women in their extended families. Two research instruments were used: a structured questionnaire, and a semi‐structured open‐ended interview. Data showed differences in subject responses depending on the research tools. The structured questionnaire revealed that women who had experienced the circumcision gave legitimization and cognitive rationalization to it. In contrast, the semi‐structured interview revealed that these same subjects reported insult: traumatization, direct negative influences, and narcissistic insult, and described emotional difficulties during the research interviews. The findings indicated that they had difficulties in mother‐daughter relationships and trust. Implications of the ritual on the continuity of polygamy and marital/sexual problems are discussed.
Family Interaction Styles of Children with Depressive Disorders, Schizophrenia‐Spectrum Disorders, and Normal Controls
Authors: HAMILTON ELIZABETH BURNEY , ASARNOW JOAN , TOMPSON MARTHA
Published: July 2004

Family interaction processes during a problem‐solving task were examined in children with depressive disorders, children with schizophrenia‐spectrum disorders, and a normal control group of community children screened for the absence of psychiatric disorder. Major findings were: a) children with depressive disorders were more likely than children with schizophrenia‐spectrum disorders and children with no psychiatric disorder to direct guilt‐inducing comments toward their parents; and b) parents of children with schizophrenia‐spectrum disorders were more likely to direct harsh critical comments toward the child than were parents of depressed children or parents of normal controls. In addition, children's and mothers' use of benign criticism was linked, while children's harsh criticism was associated with intrusion from the father, and children's self‐denigrating comments were related to specific paternal criticism. Implications of these results for understanding transactional processes associated with childhood‐onset depressive and schizophrenia‐spectrum disorders are discussed.
Racial and Gender Differences in Expressed Emotion and Interpersonal Control in Families of Persons with Schizophrenia
Authors: WUERKER ANNE K. , HAAS GRETCHEN , BELLACK ALAN
Published: July 2004

Expressed Emotion (EE) has been shown to be predictive of course or severity in many illnesses, but the studies have been largely of white middle‐class patients. This study examined gender and racial differences in parental EE level and communication patterns between the parent and patient with schizophrenia, using data from the NIMH Treatment Strategies in Schizophrenia study. Dialogues (n = 140) from 54 patient‐parent dyads were coded into the Relational Control Coding System. Resultant data (n = 13,605 sequences) were analyzed with log‐linear models. Results show that the relationship between control and EE level was stronger in African American families compared to Caucasians. Gender differences were as expected, with daughters less competitive and more deferential to their parents. Although the total number of high‐EE parents with daughters was small, patterns in these families showed parents who responded submissively in contrast to the competitive symmetry in families with male patients.
Factor Analyses of the Family Assessment Device
Authors: RIDENOUR TY A. , DALEY JAMES , REICH WENDY
Published: July 2004

The Family Assessment Device (FAD) operationalizes the McMaster Model of Family Functioning, which has been used in numerous studies, translated into seven languages, and is regarded as one of the most researched family assessment tools available. However, exploratory and confirmatory factor analyses using the 7‐by‐7 matrix of subscale correlations from the original validity study on the FAD (Epstein, Baldwin, & Bishop, 1983) indicated that the FAD subscales overlap substantially and do not assess unique dimensions of family functioning. Results of our study suggest that the conservatively best use of the FAD is using the General Functioning subscale as a summary score. A model that fits the data marginally better than the General Functioning score and a Measurement Error model, however, consisted of “Collaboration” and “Commitment” latent factors. These results illustrated the need for more extensive validity research on the FAD, because interpretation of the factors and subscales had to rely heavily on face validity.
Bone structure effect on root resorption
Authors: Otis LL , Hong JSH , Tuncay OC
Published: July 2004

Structured Abstract

Authors – Otis LL, Hong JSH, Tuncay OC

Objectives – To explore if alveolar bone shape and density might promote external apical root resorption.

Setting and Sample Population – Panoramic radiographs of 700 patients who had orthodontic treatment at Temple University were reviewed and 22 patients with radiographic evidence of root resorption on the lower incisors were selected for the study. Exclusion criteria included a history of systemic diseases, craniofacial abnormalities, tooth injury, endodontically treated teeth, and impacted teeth.

Methods – Pre‐treatment (T1) and post‐treatment (T2) cephalometric radiographs were converted into digital format and enhanced to reduce contrast variability and improve edge definition. Tooth length, root length, root area, alveolar area around the root including cortical area, area of medullary bone, and area of the symphysis were measured using an interactive software algorithm. A region of interest within the symphysis was also defined and trabecular space area and fractal dimension calculated as an estimate of bone density.

Results – Root area and tooth length were correlated negatively with changes in root area, tooth area, and root length. Larger teeth demonstrated a greater amount of root resorption. Dentoalveolar complex dimensions remained relatively unchanged during tooth movement. The amount of alveolar bone around the root, thickness of cortical bone, density of the trabecular network, and fractal dimension showed no significant correlation with the extent of the external apical root resorption.

Conclusions – The results of this study suggest that the density and morphology of the dentoalveolar complex are not significant factors in the etiology of external apical root resorption.
Taking stock: assessing the present‐planning the future ‘You don't need a weatherman to know which way the wind blows’
Authors: Hans MG
Published: July 2004

In the past, the dual nature of orthodontics has presented practitioners with unique artistic challenges and scientific opportunities. As a result, orthodontists today are enjoying the ‘Platinum Age of Productivity.’ However, a disturbing trend that promotes neither art nor science has emerged. Health care reform in the United States has transformed health care from a service to a commodity. Some orthodontists and orthodontic practice management companies have capitalized on this change in thinking and are aggressively promoting orthodontic treatment as a product. This paper examines the impact of this paradigm shift on the future of orthodontics. Particular attention is paid to the interaction of three themes: first, orthodontics as a product, secondly, the current misconception that there is a shortage of orthodontic practitioners in the United States, and thirdly, the difficulty in defining ‘excellence’ in specialty training in orthodontics. In the near future, the collision of these three concepts will result in an orthodontic ‘Perfect Storm’. The ability of our specialty to survive and thrive will be proportional to our professional behavior during these difficult times…caveat emptor.
Taking stock: passing the torch, who has the light? Reflections about teaching orthodontics at the occasion of the retirement of Prof. Lysle E. Johnston, Jr PhD
Authors: Dibbets JMH
Published: July 2004

In the Marburg (Germany) 5‐year dental curriculum, students enter the orthodontic department in the middle of their third year. Our teaching is student‐centered and problem‐solving oriented. From day 1 our students are trained to diagnose in three separate levels of development i.e. (i) craniofacial growth, (ii) development of the dentition and (iii) maturation of function. These three levels are kept separate throughout patient examination and up to the strategic treatment planning phase. The examination is performed with the help of three checklists, one for the facial morphology, one for the dentition and one for function. The three resulting problem lists then undergo reduction by selecting one ‘key problem’ for each level. Next, for every key problem three ‘standard solutions’ are offered, not in the form of appliances but as vectors that can modify growth. Finally, in a strategic planning phase, one treatment option from each of the three levels is selected and combined in a single, be it hypothetical, treatment plan. Parallel to these, students are exposed to treatment mechanics through the presentation of selected orthodontically treated patients. In our experience the advantage of this diagnostic procedure lies in the structured organization that serves as a GPS system for student and teacher and enables them a clear communication about where they are and what has to be done. By design, treatment options have taken priority over treatment mechanics. We are confident that our students, equipped with real life diagnostic skills, are well prepared for their orthodontic future.
The first year of a formal emergency medicine training programme in Papua New Guinea
Authors: Curry Chris , Annerud Carolyn , Jensen Simon , Symmons David , Lee Marian , Sapuri Mathias
Published: July 2004

Objective:  To describe a programme catalyzing the development of emergency medicine in Papua New Guinea (PNG).

Methods:  Five emergency physicians rotated through a new position of Senior Lecturer in Emergency Medicine in the University of PNG during 2003. The position was established as a consequence of emergency physician input supported by AusAID in 2002.

Results:  Fifth (final)‐year medical students and medical officers in the Emergency Department at Port Moresby General Hospital undertook formal and bedside problem based learning. The first trainees for a Master of Medicine in Emergency Medicine programme were inducted and supported. Emergency department management was provided with specialist input. Research projects were initiated, dealing with snakebite, chloroquine toxicity and HIV/AIDS. The first year of an emergency nursing curriculum was supported.

Conclusions:  There is now considerable enthusiasm for the development of emergency medicine as the hospital generalists’ specialty. Emergency nursing training has also made a start. Limitations on resources will require flexibility to sustain the project. Further support by emergency physicians will be needed.
Do radiographs requested from a paediatric emergency department in New Zealand need reporting?
Authors: Higginson Ian , Vogel Sally , Thompson John , Aickin Richard
Published: July 2004

Objectives:  To ascertain whether plain radiographs interpreted by doctors working in a paediatric ED need reporting by radiologists.

Methods:  Prospective observational study based in a paediatric teaching hospital.

Results:  The overall disagreement rate was 26.1%. The clinically significant disagreement rate was 4.8%. There was no relationship between seniority or confidence of ED doctor, and likelihood of disagreement. Disagreement was more likely where radiographs were interpreted during normal working hours (P < 0.05). Chest films, then abdominal films, then skeletal films were more likely to result in disagreement (P < 0.0001). However, this relationship was reversed when considering rates of clinically significant disagreement (P < 0.05). The highest risk of disagreement was in chest films initially thought to be normal, and the lowest in skeletal films initially thought to be abnormal.

Conclusion:  All radiographs requested on patients discharged from the paediatric ED should be reported. Reporting need not be immediate.
Why don't trainees pass the emergency medicine fellowship examination?
Authors: Rogers Ian R , Leach Debbie , Brookes Jennifer G
Published: July 2004

The pass rate in the Australasian College for Emergency Medicine Fellowship exams between 1996 and 2003 inclusive averaged 61%, substantially lower than that of other specialties with comparable training structures. The explanation for this pass rate, which many would judge as unacceptably low, is likely to be multi‐factorial. Possible factors that should be considered include trainee selection, training programme structure, the impact of the Director of Emergency Medicine Training, examination preparation, examination validity and examination reliability. Each of these potential factors needs to be addressed in a systematic fashion in the context of inevitable and increasing internal and external scrutiny of the outcomes of our training programme.
Injury patterns and preventability in prehospital motor vehicle crash fatalities in Victoria
Authors: Ryan Matt , Stella Julian , Chiu Herman , Ragg Michael
Published: July 2004

Objective:  To examine the pattern of anatomical injury in victims of motor vehicle crashes who die prior to reaching hospital. Cases were identified where death was an unexpected outcome.

Methods:  A retrospective review of autopsy case records including police reports, of all persons who died in motor vehicle crashes between 1 January 1998 and 31 December 1999 and underwent full autopsy at the Victorian Institute of Forensic Medicine (VIFM). Those cases where the victim died in the prehospital phase were examined. Abbreviate Injury Scores and Injury Severity Scores were calculated in each case. Bull's probit analysis was used to identify unexpected deaths.

Results:  There were 352 motor road crash fatalities identified that underwent autopsy at the VIFM in the study period. Two hundred and six of these were prehospital deaths involving motor vehicles, which satisfied specified criteria. 82% (95% CI: 77.7–86.3%) of cases had Abbreviated Injury Scores of 5 (critical) or 6 (incompatible with life). 80.1% (95% CI: 75.7–84.5%) had an Injury Severity Score greater than 40. 36.9% (95% CI: 34.5–39.3%) of cases had the maximum Injury Severity score of 75. 88.8% (95% CI: 85–92.7%) of cases sustained a head injury and 83.9% (95% CI: 79.8–88.2%) a chest injury. Possibly preventable fatality was identified in 30 (14.6% 95% CI: 13.9–15.3%) cases.

Conclusion:  In motor vehicle crash fatalities, most victims who die before reaching hospital do so because of major injury, with the head and chest the commonest regions involved. A large proportion of these injuries could be considered unsurvivable regardless of treatment. Earlier intervention or retrieval of such patients is unlikely to influence outcome in the majority of cases.
Does potassium concentration measured on blood gas analysis agree with serum potassium in patients with diabetic ketoacidosis?
Authors: Fu Phyllis , Douros George , Kelly Anne‐Maree
Published: July 2004

Objective:  The aims of this study were to define the maximum clinically acceptable difference between potassium concentrations on different samples and to determine the degree of agreement between potassium concentration measured on blood gas analysis and serum for patients with diabetic ketoacidosis (DKA).

Methods:  This project comprised two sub studies. In the first, 15 emergency physicians, intensivists and endocrinologists were surveyed and asked to mark on a line with markings at 0.5 mmol/L intervals, the maximum clinically acceptable differences (both above and below the ‘true’ value) between potassium concentration measured on different samples. The maximum clinically acceptable difference was calculated as the median of responses. The second study was a retrospective agreement study. Patients with an ED diagnosis of DKA were identified from a computer database. They were eligible for inclusion if they had both blood gas analysis including potassium concentration and serum potassium concentration and pH was less than 7.3. Data collected included potassium concentration on serum and blood gas samples, pH, serum glucose concentration and time of sample collections. Data were analysed using bias plot and Spearman correlation analyses.

Results:  The maximum clinically acceptable difference was defined as 0.5 mmol/L for both over and underestimation of potassium concentration. Fifty patients were studied with a median pH of 7.17 and median serum glucose of 29.5 mmol/L. Difference in potassium concentration between samples ranged from −0.9–2.9 mmol/L. 80% of sample pairs had a difference within the maximum clinically acceptable difference defined previously. The magnitude of difference between samples correlated with serum glucose (P = 0.0033, coefficient 0.41) but not with pH.

Conclusion:  This study suggests that potassium concentration derived from blood gas analysis may not be an acceptable substitute for serum potassium concentration in patients with diabetic ketoacidosis, particularly at higher serum glucose concentrations.
Incorrect instruction in the use of the Valsalva manoeuvre for paroxysmal supra‐ventricular tachycardia is common
Authors: Taylor David McD , Wong Lu Fee
Published: July 2004

Objective:  Success rates for the Valsalva manoeuvre (VM) in treatment of paroxysmal supraventricular tachycardia (SVT) vary with performance technique. This study aimed to assess whether ED doctors instruct their patients to perform the recommended VM technique (supine position for 15 s).

Methods:  A multicentre, observational study of 35 ED registrars and 17 emergency physicians. Each doctor was asked to describe how he/she would instruct a patient in SVT to perform the VM.

Results:  Only five (9.6%) doctors would position their patient correctly and 31 (59.6%) would incorrectly instruct their patient to assume a sitting or semirecumbent position. Only five (9.6%) doctors would give specific instructions to blow for at least 15 s and 34 (65.4%) would instruct their patient to blow ‘as long as you can’. Only four (7.4%) doctors would use a sphygmomanometer to measure intrathoracic pressure during the VM. There were no significant differences (P > 0.05) between the registrar and physician group responses for any study endpoint.

Conclusion:  Few ED doctors correctly instruct their patients in the VM technique recommended for management of SVT. Hence, maximal vagal tone and SVT conversion rates may not be achieved in many cases. The use of the recommended VM technique is encouraged.
Two types of non‐selective cation channel opened by muscarinic stimulation with carbachol in bovine ciliary muscle cells
Authors: Takai Yoshiko , Sugawara Ryoichi , Ohinata Hiroshi , Takai Akira
Published: July 2004

In the ciliary muscle, the tonic contraction requires a sustained influx of Ca2+ through the cell membrane. However, little has hitherto been known about the route(s) of Ca2+ influx in this tissue that lacks voltage‐gated Ca2+ channels. To identify ion channels as the Ca2+ entry pathway we studied the effects of carbachol (CCh) on freshly isolated bovine ciliary muscle cells by whole‐cell voltage clamp. Experiments were carried out using pipettes filled with K+‐free solution containing 100 mm caesium aspartate, 5 mm BAPTA and 180 μm GTP (pH 7.0; the intracellular free Ca2+ concentration, [Ca2+]i= 70 nm). CCh evoked an inward current showing polarity reversal at a holding potential near 0 mV. Analysis of the current noise distinguished two types of non‐selective cation channel (NSCCL and NSCCS) with widely different unitary conductances (35 pS and 100 fS). The ratios of the permeabilities to Li+, Na+, Cs+, Mg2+, Ca2+, Sr2+ and Ba2+, estimated by cation replacement procedures, were 0.9: 1.0: 1.5: 0.2: 0.3: 0.4: 0.5 for NSCCL, and 1.0: 1.0: 1.8: 2.5: 2.6: 3.2: 5.0 for NSCCS. NSCCS, but not NSCCL, was strongly inhibited by elevation of [Ca2+]i. Both NSCCL and NSCCS were dose‐dependently inhibited by 1–100 μm SKF96365, La3+ and Gd3+, which also inhibited the tonic component of the contraction produced in muscle bundles by CCh without markedly affecting the initial phasic component. NSCCL and/or NSCCS may serve as a major Ca2+ entry pathway required for sustained contraction of the bovine ciliary muscle. RT‐PCR experiments in the bovine ciliary muscle (whole tissue) detected mRNAs of several transient receptor potential (TRP) channel homologues (TRPC1, TRPC3, TRPC4 and TRPC6), which are now regarded as possible molecular candidates for receptor‐operated cation channels.
Role of adenosine transport in gestational diabetes‐induced l‐arginine transport and nitric oxide synthesis in human umbilical vein endothelium
Authors: Vásquez Gustavo , Sanhueza Felipe , Vásquez Rodrigo , González Marcelo , Martín Rody San , Casanello Paola , Sobrevia Luis
Published: July 2004

Gestational diabetes is associated with increased l‐arginine transport and nitric oxide (NO) synthesis, and reduced adenosine transport in human umbilical vein endothelial cells (HUVEC). Adenosine increases endothelial l‐arginine/NO pathway via A2 purinoceptors in HUVEC from normal pregnancies. It is unknown whether the effect of gestational diabetes is associated with activation of these purinoceptors or altered expression of human cationic amino acid transporter 1 (hCAT‐1) or human equilibrative nucleoside transporter 1 (hENT1), or endothelial NO synthase (eNOS) in HUVEC. Cells were isolated from normal or gestational diabetic pregnancies and cultured up to passage 2. Gestational diabetes increased hCAT‐1 mRNA expression (2.4‐fold) and activity, eNOS mRNA (2.3‐fold), protein level (2.1‐fold), and phosphorylation (3.8‐fold), but reduced hENT1 mRNA expression (32%) and activity. Gestational diabetes increased extracellular adenosine (2.7 μm), and intracellular l‐arginine (1.9 mm) and l‐citrulline (0.7 mm) levels compared with normal cells (0.05 μm, 0.89 mm, 0.35 mm, respectively). Incubation of HUVEC from normal pregnancies with 1 μm nitrobenzylthioinosine (NBMPR) mimicked the effect of gestational diabetes, but NBMPR was ineffective in diabetic cells. Gestational diabetes and NBMPR effects involved eNOS, PKC and p42/44mapk activation, and were blocked by the A2a purinoceptor antagonist ZM‐241385. Thus, gestational diabetes increases the l‐arginine/NO pathway involving activation of mitogen‐activated protein (MAP) kinases, protein kinase C (PKC) and NO cell signalling cascades following activation of A2a purinoceptors by extracellular adenosine. A functional relationship is proposed between adenosine transport and modulation of l‐arginine transport and NO synthesis in HUVEC, which could be determinant in regulating vascular reactivity in diabetes mellitus.
Variations in excitability of single human motor axons, related to stochastic properties of nodal sodium channels
Authors: Hales* John Paul , Lin Cindy Shin‐Yi , Bostock Hugh
Published: July 2004

Threshold variability of single human motor axons was studied by delivering 0.1 ms constant current stimuli of randomly varied intensity over the ulnar nerve at the elbow, and recording all‐or‐none potentials from flexor carpi ulnaris. In nine normal subjects, a single unit was tested with 8–11 000 stimuli at intervals of 0.5 s. After allowing for slow changes in excitability, the probability of excitation was in all cases well fitted by a cumulative Gaussian function. The relative spread (RS) of thresholds (s.d./mean) averaged 1.65 ± 0.26% (mean ±s.d., n= 9). When threshold was tested 20 ms after the start of a polarizing current, RS increased on depolarization and decreased on hyperpolarization. The product RS × mean threshold also increased on depolarization, especially when threshold was reduced by more than 50%. When the mean was reduced by 90%, RS increased above 50% and the axon sometimes fired spontaneously. Threshold variability was simulated by a computer model of a single node of Ranvier, in which the variability arose because of the stochastic behaviour of nodal sodium channels. The observed values of RS, and potential dependence of RS, were well modelled by a node with 60 000 sodium channels, of which about 1% were modelled as persistent sodium channels. Threshold variations in the model at resting potential were not primarily due to fluctuations in the state of the node before the stimulus was delivered, but rather to the variable activation of channels by the stimulus pulse. On depolarization, however, current through (mainly persistent) sodium channels caused appreciable fluctuations in membrane potential, which increased RS and the probability of spontaneous firing.
Role of ATP‐conductive anion channel in ATP release from neonatal rat cardiomyocytes in ischaemic or hypoxic conditions
Authors: Dutta Amal K. , Sabirov Ravshan Z. , Uramoto Hiromi , Okada Yasunobu
Published: July 2004

It is known that the level of ATP in the interstitial spaces within the heart during ischaemia or hypoxia is elevated due to its release from a number of cell types, including cardiomyocytes. However, the mechanism by which ATP is released from these myocytes is not known. In this study, we examined a possible involvement of the ATP‐conductive maxi‐anion channel in ATP release from neonatal rat cardiomyocytes in primary culture upon ischaemic, hypoxic or hypotonic stimulation. Using a luciferin–luciferase assay, it was found that ATP was released into the bulk solution when the cells were subjected to chemical ischaemia, hypoxia or hypotonic stress. The swelling‐induced ATP release was inhibited by the carboxylate‐ and stilbene‐derivative anion channel blockers, arachidonic acid and Gd3+, but not by glibenclamide. The local concentration of ATP released near the cell surface of a single cardiomyocyte, measured by a biosensor technique, was found to exceed the micromolar level. Patch‐clamp studies showed that ischaemia, hypoxia or hypotonic stimulation induced the activation of single‐channel events with a large unitary conductance (∼390 pS). The channel was selective to anions and showed significant permeability to ATP4‐ (PATP/PCl∼ 0.1) and MgATP2‐ (PATP/PCl∼ 0.16). The channel activity exhibited pharmacological properties essentially identical to those of ATP release. These results indicate that neonatal rat cardiomyocytes respond to ischaemia, hypoxia or hypotonic stimulation with ATP release via maxi‐anion channels.
GRAVITATIONAL WAVES IN GENERALISED BRANS–DICKE THEORY
Authors: SAHOO B. K. , SINGH L. P.
Published: July 2004

We have solved cosmological gravitational wave (GW) equation in the framework of generalised Brans–Dicke (GBD) theory for all epochs of the Universe. The solutions are expressed in terms of the present value ω0 of the Brans–Dicke coupling parameter. We also obtain the constraints on ω0 for the solutions to represent growing modes in different epochs.
ABOUT THE GENERALIZED UNCERTAINTY PRINCIPLE
Authors: XIANG LI , SHEN YOU-GEN
Published: July 2004

Some consequences of the generalized uncertainty principle (GUP) are investigated, including the deformations of the Wein's law and the state equations of black body radiation. The effects of the GUP on the thermodynamics of black holes are investigated by a heuristic method. A bound on the luminosity of the black hole radiation is obtained. The logarithmic corrections to the Bekenstein–Hawking entropy are obtained in three cases. The potential relation between the GUP and the holographic principle is also briefly discussed.
NEW SYMMETRY CURRENT FOR MASSIVE SPIN-3/2 FIELDS
Authors: PILLING TERRY
Published: July 2004

We present several new results which will be of value to theorists working with massive spin-3/2 vector-spinor fields as found, for example, in low and intermediate energy hadron physics and also linearized supergravity. The most general Lagrangian and propagator for a vector-spinor field in d dimensions is given. It is shown that the observables of the theory are invariant under a novel continuous symmetry group which is also extended to an algebra. A new technique is developed for exploring the consequences of the symmetry and a previously unknown conserved vector current and charge are found. The current leads to new interactions involving spin-3/2 particles and may have important phenomenological consequences.
ELECTRICAL RESISTIVITY OF PLATINUM AND GOLD THIN FILMS: A THEORETICAL APPROACH
Authors: CATTANI M. , SALVADORI M. C.
Published: July 2004

In a recent work we have proposed a quantum-mechanical approach to explaining our resistivity experimental results for platinum and gold thin films. Good agreement was found between theory and experiment. In that work only the main features of our calculations were pointed out. In the present work the quantum approach calculations are shown in detail and the predictions are compared with our experimental data.
Proinflammatory cytokines alter/reduce esophageal circular muscle contraction in experimental cat esophagitis
Authors: Cao Weibiao , Cheng Ling , Behar José , Fiocchi Claudio , Biancani Piero , Harnett Karen M.
Published: July 2004

Cholinergic mechanisms are largely responsible for esophageal contraction in response to swallowing or to in vitro electrical field stimulation (EFS). After induction of experimental esophagitis by repeated acid perfusion, the responses to swallowing and to EFS were significantly reduced but contraction in response to ACh was not affected, suggesting that cholinergic mechanisms are damaged by acid perfusion but that myogenic mechanisms are not. Measurements of ACh release in response to EFS confirmed that release of ACh was reduced in esophagitis compared with normal controls. To examine factors contributing to this neuropathy, normal esophageal strips were incubated for 1–2 h with the proinflammatory cytokines IL-1β (100 U/ml), IL-6 (1 ng/ml), or TNF-α (1 ng/ml). IL-1β and IL-6 levels, measured by Western blot analysis, increased in esophagitis compared with normal circular muscle. IL-1β and IL-6 reduced contraction in response to EFS (2–10 Hz, 0.2 ms) but did not affect ACh-induced contraction, suggesting that these cytokines inhibit ACh release without affecting myogenic contractile mechanisms. EFS-induced ACh release was significantly reduced in normal esophageal strips by incubation in IL-1β or IL-6, suggesting that they may contribute to the contractility changes. TNF-α at 1 ng/ml, however, did not affect the response to ACh or to electrical stimulation but inhibited both at higher concentrations. TNF-α levels were low in normal muscle and did not increase with esophagitis. The data suggest that the proinflammatory cytokines IL-1β and IL-6 contribute to reduced esophageal contraction by inhibiting release of ACh from myenteric neurons.
Epidermal growth factor and interleukin-1β synergistically stimulate the production of nitric oxide in rat intestinal epithelial cells
Authors: Kitagawa Katsuhiko , Hamada Yoshinori , Kato Yasunori , Nakai Koji , Nishizawa Mikio , Ito Seiji , Okumura Tadayoshi
Published: July 2004

Epidermal growth factor (EGF) is one of the trophic factors for intestinal adaptation after small bowel transplantation (SBT). A recent report indicates that nitric oxide (NO) has cytoprotective effects on bacterial translocation (BT) after SBT. We hypothesized that EGF stimulates the expression of the inducible NO synthase (iNOS) gene in the graft after SBT, followed by increased production of NO, resulting in the decrease of BT. Intestinal epithelial cells (IEC)-6 were treated with EGF and/or IL-1β in the presence and absence of phosphatidylinositol 3-kinase (PI3-kinase) and EGF receptor kinase inhibitors (LY-294002 and tyrphostin A25). The induction of NO production and iNOS and its signal molecules, including the inhibitory protein of NF-κB (IκB), NF-κB, and Akt, were analyzed. IL-1β stimulated the degradation of IκB and the activation of NF-κB but had no effect on iNOS induction. EGF, which had no effect on the NF-κB activation and iNOS induction, stimulated the upregulation of type 1 IL-1 receptor (IL-1R1) through PI3-kinase/Akt. Simultaneous addition of EGF and IL-1β stimulated synergistically the induction of iNOS, leading to the increased production of NO. Our results indicate that EGF and IL-1β stimulate two essential signals for iNOS induction in IEC-6 cells: the upregulation of IL-1R1 through PI3-kinase/Akt and the activation of NF-κB through IκB kinase, respectively. Simultaneous addition of EGF and IL-1β can enhance the production of NO, which may contribute to the cytoprotective effect of EGF against intestinal injury.
Transgenic upregulation ofIK1in the mouse heart leads to multiple abnormalities of cardiac excitability
Authors: Li Jingdong , McLerie Meredith , Lopatin Anatoli N.
Published: July 2004

To assess the functional significance of upregulation of the cardiac current ( IK1), we have produced and characterized the first transgenic (TG) mouse model of IK1upregulation. To increase IK1density, a pore-forming subunit of the Kir2.1 (green fluorescent protein-tagged) channel was expressed in the heart under control of the α-myosin heavy chain promoter. Two lines of TG animals were established with a high level of TG expression in all major parts of the heart: line 1 mice were characterized by 14% heart hypertrophy and a normal life span; line 2 mice displayed an increased mortality rate, and in mice ≤1 mo old, heart weight-to-body weight ratio was increased by >100%. In adult ventricular myocytes expressing the Kir2.1-GFP subunit, IK1conductance at the reversal potential was increased ∼9- and ∼10-fold in lines 1 and 2, respectively. Expression of the Kir2.1 transgene in line 2 ventricular myocytes was heterogeneous when assayed by single-cell analysis of GFP fluorescence. Surface ECG recordings in line 2 mice revealed numerous abnormalities of excitability, including slowed heart rate, premature ventricular contractions, atrioventricular block, and atrial fibrillation. Line 1 mice displayed a less severe phenotype. In both TG lines, action potential duration at 90% repolarization and monophasic action potential at 75–90% repolarization were significantly reduced, leading to neuronlike action potentials, and the slow phase of the T wave was abolished, leading to a short Q-T interval. This study provides a new TG model of IK1upregulation, confirms the significant role of IK1in cardiac excitability, and is consistent with adverse effects of IK1upregulation on cardiac electrical activity.
Insulin resistance does not diminish eNOS expression, phosphorylation, or binding to HSP-90
Authors: Fulton David , Harris M. Brennan , Kemp Bruce E. , Venema Richard C. , Marrero Mario B. , Stepp David W.
Published: July 2004

Previously, using an animal model of syndrome X, the obese Zucker rat (OZR), we documented impaired endothelium-dependent vasodilation. The aim of this study was to determine whether reduced expression or altered posttranslational regulation of endothelial nitric oxide synthase (eNOS) underlies the vascular dysfunction in OZR rats. There was no significant difference in the relative abundance of eNOS in hearts, aortas, or skeletal muscle between lean Zucker rats (LZR) and OZR regardless of age. There was no difference in eNOS mRNA levels, as determined by real-time PCR, between LZR and OZR. The inability of insulin resistance to modulate eNOS expression was also documented in two additional in vivo models, the ob/ob mouse and the fructose-fed rat, and in vitro via adenoviral expression of protein tyrosine phosphatase 1B in endothelial cells. We next investigated whether changes in the acute posttranslational regulation of eNOS occurs with insulin resistance. Phosphorylation of eNOS at S632 (human S633) and T494 was not different between LZR and OZR; however, phosphorylation of S1176 was significantly enhanced in OZR. Phosphorylation of S1176 was not different in the ob/ob mouse or in fructose-fed rats. The association of heat shock protein 90 with eNOS, a key regulatory step controlling nitric oxide and aberrant O2−production, was not different between OZR and LZR. Taken together, these results suggest that changes in eNOS expression or posttranslation regulation do not underlie the vascular dysfunction seen with insulin resistance and that other mechanisms, such as altered localization, reduced availability of cofactors, substrates, and the elevated production of O2−, may be responsible.
Contribution to sympathetic vasomotor tone of tonic glutamatergic inputs to neurons in the RVLM
Authors: Horiuchi Jouji , Killinger Suzanne , Dampney Roger A. L.
Published: July 2004

The role of excitatory amino acid (EAA) receptors in the rostral ventrolateral medulla (RVLM) in maintaining resting sympathetic vasomotor tone remains unclear. It has been proposed that EAA receptors in the RVLM mediate excitatory inputs both to presympathetic neurons and to interneurons in the caudal ventrolateral medulla (CVLM), which then provide a counterbalancing inhibition of RVLM presympathetic neurons. In this study, we tested this hypothesis by determining the effect of blockade of EAA receptors in the RVLM on mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA), after inhibition of CVLM neurons. In anesthetized rats, bilateral injections of muscimol in the CVLM increased MAP, HR, and RSNA. Subsequent bilateral injections of kynurenic acid (Kyn, 2.7 nmol) in the RVLM caused a modest reduction of ∼20 mmHg in the MAP but had no effect, when compared with the effect of vehicle injection alone, on HR or RSNA. By ∼50 min after the injections of Kyn or vehicle in the RVLM, the MAP had stabilized at a level close to its original baseline level, but the HR and RSNA stabilized at levels above baseline. The results indicate that removal of tonic EAA drive to RVLM neurons has little effect on the tonic activity of RVLM presympathetic neurons, even when inputs from the CVLM are blocked. Thus the tonic activity of RVLM presympathetic neurons under these conditions is dependent on excitatory synaptic inputs mediated by non-EAA receptors and/or the autoactivity of these neurons.
Differential regulation of mesangial cell mitogenesis by cAMP phosphodiesterase isozymes 3 and 4
Authors: Cheng Jingfei , Thompson Michael A. , Walker Henry J. , Gray Catherine E. , Diaz Encarnacion Montserrat M. , Warner Gina M. , Grande Joseph P.
Published: July 2004

Mesangial cell (MC) mitogenesis is regulated through “negative cross talk” between cAMP-PKA and ERK signaling. Although it is widely accepted that cAMP inhibits mitogenesis through PKA-mediated phosphorylation of Raf-1, recent studies have indicated that cAMP-mediated inhibition of mitogenesis may occur independently of Raf-1 phosphorylation or without inhibiting ERK activity. We previously showed that MCs possess functionally compartmentalized intracellular pools of cAMP that are differentially regulated by cAMP phosphodiesterases (PDE); an intracellular pool directed by PDE3 but not by PDE4 suppresses mitogenesis. We therefore sought to determine whether there was a differential effect of PDE3 vs. PDE4 inhibitors on the Ras-Raf-MEK-ERK pathway in cultured MC. Although PDE3 and PDE4 inhibitors activated PKA and modestly elevated cAMP levels to a similar extent, only PDE3 inhibitors suppressed MC mitogenesis (−57%) and suppressed Raf-1 kinase and ERK activity (−33 and −68%, respectively). Both PDE3 and PDE4 inhibitors suppressed B-Raf kinase activity. PDE3 inhibitors increased phosphorylation of Raf-1 on serine 43 and serine 259 and decreased phosphorylation on serine 338; PDE4 inhibitors were without effect. Overexpression of a constitutively active MEK-1 construct reversed the antiproliferative effect of PDE3 inhibitors. PDE3 inhibitors also reduced cyclin A levels (−27%), cyclin D and cyclin E kinase activity (−30 and −50%, respectively), and induced expression of the cell cycle inhibitor p21 (+90%). We conclude that the antiproliferative effects of PDE3 inhibitors are mechanistically related to inhibition of the Ras-Raf-MEK-ERK pathway. Additional cell cycle targets of PDE3 inhibitors include cyclin A, cyclin D, cyclin E, and p21.