bluuebunny/crossref_metadata_2025 huggingface dataset:
You don't have to be Jewish: But Freud Did
Authors: De Saxe Ian
Published: March 2003

Objective: Despite recurrent suggestions that Freud's theories are no longer relevant, this paper seeks to demonstrate that all modern perspectives on the human psyche which investigate ‘binaries’[ 1 ] or ‘othernesses’ in the mind, derive from Freud's own uneasy position as an assimilated Jew struggling to be accepted by the anti-Semitic establishment in Vienna.

Conclusions: Freud's identification of the concepts of conscious and unconscious and differences in male and female sexuality has now broadened into a general focus on ‘othernesses’ which are relevant to current understandings of narcissism and boundaries. Clinically, this offers us novel views of our patients' minds, rather than the usual ‘sick’ and ‘well’ categories.
Psychiatry and the Scientific Method
Authors: Shea Peter
Published: March 2003

Objective: To identify some of the factors that limit the usefulness of the scientific method in psychiatric research.

Conclusions: Scientific method has only a limited application in psychiatry and it should not become the touchstone by which all psychiatric practice is judged.
Strategies to Manage Inpatient Drug Costs
Authors: Emmerson Brett , Estensen Axel , Powell Jacinta , Iwaniak Janice
Published: March 2003

Objective: The aim of this paper is to analyse the reasons for a major increase in expenditure on inpatient pharmaceutical costs over a two year period and to describe strategies developed to prevent further increases.

Conclusions: By educating our medical staff on the costs of the most commonly prescribed medications and favouring cost effective medications such as risperidone over olanzapine we have been able to contain our inpatient drug costs and achieve a 14% reduction this financial year.
Patient, Client or Consumer? A Survey of Preferred Terms
Authors: Lloyd Chris , King Robert , Bassett Hazell , Sandland Shelley , Savige Gabrielle
Published: March 2003

Objective: To ascertain how recipients of a mental health service like to be referred, given recent debate about this topic.

Method: A survey was conducted in an Australian regional mental health service.

Results: The 125 respondents were participating in a variety of inpatient and outpatient programmes. “Client” was the preferred term by 34% of respondents, with 28% preferring “consumer”, 23% preferring “patient” and 15% preferring to be known as something other than these terms. Analysis of the data suggested that the term preferred depends to a large extent on the treatment setting and that age and gender of the person have little or no influence on term preference.

Conclusions: The reform of mental health services has emphasised collaborative partnerships and carer and consumer involvement in all aspects of service delivery. It is increasingly important that service providers listen to the voice of recipients in a number of areas, including how recipients are described and addressed.
Hand-Held Computers and Consultation-Liaison Psychiatry: A Practical Tool for the Information Age
Authors: Ryan Christopher , Kotze Beth
Published: March 2003

Objective: To demonstrate the practical utility of a new generation of hand-held computers in the practice of consultation-liaison psychiatry.

Method: In their work over the last 3 years as consultation-liaison psychiatrists in two large general hospitals in Sydney, the authors have developed a series of clinical databases carried on small computers. Illustrative examples demonstrate the utility of this dynamic learning tool.

Results: An affordable pocket computer provides a new means of accumulating, organizing and readily accessing the reams of information required by the consultation-liaison psychiatrist in day to day clinical work.

Conclusions: The information explosion in psychiatry, and in psychiatric pharmacology in particular, has placed enormous demands upon the practicing psychiatrist. Retaining and gaining access to this information is even more onerous for the consultation-liaison psychiatrist, who must maintain a familiarity with general medical illness and its treatment and investigation. The use of hand-held computers to assist is relevant to continuing medical education and embedding evidence-based medicine in clinical practice.
The “Maga Barndi” Mental Health Service for Aboriginal People in Western Australia
Authors: Laugharne Jonathan , Glennen Michael , Austin June
Published: March 2003

Objective: This paper describes the implementation of the “Maga Barndi” pilot project while highlighting certain issues relevant to delivering psychiatric services to Aboriginal people.

Method: The process of developing and implementing the project is described with an emphasis on those aspects which seem to enhance accessibility and acceptability to the Aboriginal community.

Results: Over the 2-year period of the project, a caseload of 61 Aboriginal patients was established within Geraldton. A further 22 Aboriginal patients were managed at a variety of regional centres and another 52 at the Regional Prison. This represented a marked increase in service utilisation by local Aboriginal people. Psychiatric admissions for Aboriginal patients to the local hospital were reduced by 58% in the year following service commencement. Location of the project within an Aboriginal-controlled health centre with access to Aboriginal health workers and a flexible assertive community management approach were key factors in facilitating patient access to the service.

Conclusions: The project succeeded in its objective of pioneering a culturally sensitive psychiatric service for Aboriginal people in Geraldton and the Midwest. Lessons learnt during the development of the project may be useful to other services seeking to improve their accessibility and acceptability to Aboriginal people.
South Metro's Men's Respite: An Innovative Service for Violent Men
Authors: Pennebaker Duane , Olesen Terry
Published: March 2003

Objectives: The study describes the evaluation of an integrated men's domestic violence respite centre, the South Metro Men's Respite (SMMR), in Western Australia. In addition to recognising the novel approach of SMMR to client services, assessments of mental illness in clients presenting to the service were made and compared with available norms. Furthermore, the types of services provided by the SMMR were assessed against other Australian domestic violence programs for men.

Conclusions: The results suggested that even with stringent assessment criteria, a large number of the SMMR's presenting clients displayed symptoms of depression, anxiety, paranoia, and psychoticism at levels that indicated a need for treatment. The SMMR sample had levels of anxiety higher than that of the adult male psychiatric inpatients and outpatients, which would imply the suitability of the Assertive Community-based Treatment (ACT) component of the service. The SMMR's innovative approach aimed to meet service gaps in providing for men who are perpetrators of domestic violence. The service comparison review established that while seven other programs within Australia had provisions for child custody/parenting, spousal independence, addiction, personal responsibility, alternatives to violence, gender roles, and communication content, the ability to provide assertive outreach to the men was shared by only two other programs in Australia.
Concordance between Patients and Their Case Managers Using the Health of the Nation Outcome Scales
Authors: Trauer Tom , Callaly Tom
Published: March 2003

Objective: Outcome assessment benefits from multiple perspectives, but these may differ. We aimed to compare patient and clinician ratings on respective versions of a well-known outcome assessment scale.

Method: Case managers and their patients rated the patient's mental health problems using the clinician and self-rating forms of the Health of the Nation Outcome Scales (HoNOS).

Results: One third of patients approached returned their self-rating form; non-return was associated with involuntary legal status. Patient ratings were significantly higher (worse) than case manager ratings on four of the twelve HoNOS items, and significantly lower on one. Overall, agreement levels were slight to moderate, but particularly low for the depressed mood item. Case managers tended to overestimate the actual degree of similarity between their own ratings and those of their patients.

Conclusions: The findings support the proposition that patient and clinician perceptions of the patient’ problems represent two different sets of information.
Decision-Making in Community Treatment Orders: A Comparison of Clinicians and Mental Health Review Board Members
Authors: Jaworowski Sol , Guneva Rumiana
Published: March 2003

Objective: The aim of this paper is to determine the level of consistency in decision-making between mental health clinicians and members of the Mental Health Review Board regarding Community Treatment Order (CTO) discharge.

Method: Vignettes were composed by the first author and shown to 50 senior clinicians and 50 members of the Victorian Mental Health Review Board who were asked to indicate whether or not they would discharge the described patients from their current CTO and to justify their decision. Participants were also asked to comment on the usefulness of clinical guidelines which the first author developed to assist decision-making in this area.

Results: In the main, there was concordance between the ratings of clinicians and VMHRB members. The guidelines were perceived to be useful.

Conclusions: The agreement between clinicians and MHRB members suggests that the Mental Health Act in this area is clinically meaningful and able to be applied reliably.
What, With What, and to Whom: The Limits of Psychiatry
Authors: Ratcliff Eric
Published: March 2003

Objective: To identify some general principles for use in deciding what is psychiatry and what is not.

Method: An overview of matters referred to the Clinical Practice Advisory Committee of the Royal Australian and New Zealand College of Psychiatrists.

Results: Three domains of psychiatric practice are identified: competence, ethics and performance. A number of quasi-paradoxical dichotomies in the nature of psychiatry have emerged: doctor-specialist, scientist-clinician, humane-commercial. These are not exhaustive.

Conclusion: Some useful generalisations can be made about the limits of acceptable psychiatric practice but, within these, there is a need for further investigation of the realities of practice. A pilot study of clinicians' opinions is proposed.
What Causes More Destruction, AIDS or AID? Psychiatry in Zambia
Authors: Gleisner John
Published: March 2003

Objective: To describe the state of mental health services in Zambia.

Conclusions: Mental health services in Zambia are in a dreadful state, partly brought about by being afforded a low priority rating, in turn through a miscalculation. Richer countries may be in a position to help remedy Zambia's problems in this area.
Is there a Place for Psychoanalysis in Public Mental Health?
Authors: Curnow Rick
Published: March 2003

Objective: To describe a programme of theoretical and clinical seminars, and to discuss the benefit of introducing a psychoanalyst's perspective to the supervisory process in psychiatric training.

Conclusions: Vignettes of work from seminars provide examples that explain how the teaching that occurs is at the level of understanding of the countertransference experience, rather than at the level of psychoanalytic formulations. An application of the psychoanalytic concept of containment is found to be helpful to the trainees in understanding patients, particularly those with borderline personality disorder.
The Phenomenon of Collocation: a Local Solution to an Australian Problem
Authors: Taylor Andrea , Bernardi Elsa
Published: March 2003

Objective: To describe the phenomenon of collocation in a metropolitan mental health service.

Conclusions: Collocation is the locating of private and public mental health sectors in a joint working relationship. In the context of increasing numbers of clients referred to a public Community Mental Health Service, a restricted ability to refer clients to other practitioners, a limited number of medical officer hours available and a new purpose built premises with spare rooms, the Service investigated and implemented a model of collocation. This in effect locates private and public psychiatrists together, working from the same premises. Collocation has been a modest local initiative increasing cooperation between the public and private sector and partially increasing consumer choice and private psychiatrist availability
A Right Royal ‘Hoo-Ha’: Why we Should Not Change the College Name
Authors: Kisely Stephen
Published: March 2003

Objective: To identify some reasons why the College should not change its name.

Conclusions: A change of name is premature, irrelevant and contrary to the will of Australian voters. It ignores the experience of New Zealand, Ireland and Canada and confuses a recognition of the College's standing with ties to the monarchy. More useful reforms to the College would include the right to directly elect our President and Executive.
Popliteal artery pseudo‐aneurysm following penetrating trauma
Authors: Bapuraj Jayapalli Rajiv , Thingnam Shyam , Rajak Chaturbhuj Lal
Published: March 2003

Popliteal artery pseudo‐aneurysm due to accidental penetrating trauma, once common during world wars, is now rare. It may require amputation due to ischaemic complication. One such case is detailed here. The angiographic findings, complications, management and literature review are provided.
‘Stalkitis’ in a pregnant 32‐year‐old woman: A rare cause of diabetes insipidus
Authors: Leggett DAC , Hill PT , Anderson RJ
Published: March 2003

A case of lymphocytic infundibulo‐neurohypophysitis (LINH) or ‘stalkitis’ in a 32‐year‐old woman who presented with diabetes insipidus (DI) during pregnancy is reported here. The diagnosis was made with MR imaging. The clinical and radiological features of this rare disorder and the differential diagnosis of infundibular mass lesions are discussed. The differentiation from lymphocytic adenohypophysitis (LAH) is made. No improvement of the DI accompanying LINH is achieved with trans‐sphenoidal surgery. Hence, recognition of typical cases with MR imaging and appropriate medical management avoids unnecessary neurosurgery. This is the second reported case of LINH associated with pregnancy and may suggest an association.
Covering the CSF space: Does teaching make a difference?
Authors: Campbell G , Wynne C.J. , Baggarley S
Published: March 2003

Following a paediatric teaching course for radiation oncology registrars which specifically addressed the method for planning cranial irradiation, a lateral skull simulation film was sent to all attendees to assess the effect of the teaching. To assess current clinical practice in New Zealand, a copy of the same radiograph was sent to radiation oncologists who had not attended the course. Recommendations from the course were that 10‐mm margins should be placed in the regions of the cribiform plate and the floor of the middle cranial fossa. However, only 6.9% of the attendees marked the film with the recommended 10‐mm margins. Dose profiles are also presented to support the use of 10‐mm margins.
Clinical audit of a new radiation oncology department in the first 20 months of establishment
Authors: Hui Andrew , Berry Martin P , Delaney Geoffrey
Published: March 2003

This audit was carried out to examine the workload statistics of the Radiation Oncology Department at Liverpool Hospital in its first 20 months of operation, and their implications for the delivery of radiation oncology services in the Southwestern Sydney Area Health Service (SWSAHS). Data on patient demographics, primary diagnosis and radiotherapy treatment details from April 1995 to December 1996 were analysed. In this time period, 1329 new patients were seen; 90.6% of them lived in the local area health service and ~ 30% came from a non‐English‐speaking background. The most common primary tumour sites were breast (25%), prostate (17%) and lung (15%). Nine hundred and ninety‐eight of the new patients (74%) proceeded to have radiotherapy. Fifty‐seven per cent were treated radically with curative or adjuvant intent, the remainder were treated palliatively for symptom control or local control. The most commonly used fractionation schedules were 31–35 fractions for radical treatment and 1–5 fractions for palliative treatment. Forty patients (4%) did not complete the treatment course as planned. Eighty‐nine patients (9%) were retreated in the same time period. These workload statistics were helpful in determining ongoing workload and planning future expansion.
Primary intrathoracic malignant fibrous histiocytoma and angiosarcoma
Authors: Pui Margaret H , Yu Shen‐Ping , Chen Jing‐Di
Published: March 2003

Primary intrathoracic malignant fibrous histiocytoma and angiosarcoma are rare sarcomas constituting less than 0.2% of lung cancers. The typical imaging appearance is a large, well‐circumscribed, non‐cavitating, non‐calcified, peripheral lung mass without hilar or mediastinal lymphadenopathy. Bronchoscopy and percutaneous needle aspiration are of limited value in differential diagnosis, and thoracotomy is warranted for definitive diagnosis.
Chest radiographic findings following video‐assisted thoracoscopic lung volume reduction surgery for emphysema
Authors: Costello Philip , Petrucco Michael
Published: March 2003

Surgical reduction of lung volume is being investigated as a promising alternative in the treatment of selected patients with severe debilitating emphysema. Following bilateral video‐assisted thoracoscopic surgical resection (VATS) of emphysematous lung tissue, patients show improvements in exercise tolerance, dyspnoea, increases in oxygenation, decreased airway obstruction and enhanced quality of life. The postoperative findings in the first 24 patients who underwent bilateral VATS volume reduction are described. Pneumothoraces developed in all patients, often with unusual shapes related to the surgical sutures. Perihilar, pulmonary and paramediastinal pulmonary parenchymal opacities were seen in approximately half of the patients, representing areas of pulmonary contusion, atelectasis and/or haemorrhage associated with the staple lines. The purpose of the present study is to describe the immediate postoperative chest radiographic appearances and to familiarize radiologists with the surgical procedure.
Diffusion‐weighted magnetic resonance imaging of intracranial epidermoid tumours
Authors: Laing Andrew Dp , Mitchell Peter J , Wallace David
Published: March 2003

Intracranial epidermoids can closely mimic cerebrospinal fluid (CSF) on MRI and CT. Therefore epidermoids can be difficult to detect, or distinguish from CSF. Three cases of intracranial epidermoid are presented, one of which closely mimicked an arachnoid cyst on CT and routine MRI sequences. Diffusion‐weighted magnetic resonance imaging (DWI) was performed. All three epidermoids demonstrated marked restriction of diffusion relative to CSF, clearly defining the extent of each lesion, and allowing differentiation from an arachnoid cyst or an enlarged CSF space.
Radiology of the nasopharynx: Pictorial essay
Authors: Chong Vincent Fh , Fan Yoke‐Fun
Published: March 2003

The nasopharynx, located just below the central skull base, is a difficult area to evaluate clinically. Endoscopic examination provides useful information but cannot delineate submucosal disease. Benign lesions of the nasopharynx are relatively uncommon. They include Thornwaldt cyst, juvenile angiofibroma, haemangioma, haemangiopericytoma, Kimura’s disease, branchial cleft cyst, oncocytoma, amyloidoma, and non‐ossifying fibromyxoid tumours. The most common malignant lesions are carcinomas and lymphomas. Other malignant neoplasms such as adenocystic carcinomas are rarely seen. The purpose of the present pictorial review is to highlight the salient normal anatomy of the nasopharynx and the spectrum of pathological anatomy.
Acceptable levels of digital image compression in chest radiology
Authors: Smith I , Roszkowski A , Slaughter R , Sterling D
Published: March 2003

The introduction of picture archival and communications systems (PACS) and teleradiology has prompted an examination of techniques that optimize the storage capacity and speed of digital storage and distribution networks. The general acceptance of the move to replace conventional screen‐film capture with computed radiography (CR) is an indication that clinicians within the radiology community are willing to accept images that have been ‘compressed’. The question to be answered, therefore, is what level of compression is acceptable. The purpose of the present study is to provide an assessment of the ability of a group of imaging professionals to determine whether an image has been compressed. To undertake this study a single mobile chest image, selected for the presence of some subtle pathology in the form of a number of septal lines in both costphrenic angles, was compressed to levels of 10:1, 20:1 and 30:1. These images were randomly ordered and shown to the observers for interpretation. Analysis of the responses indicates that in general it was not possible to distinguish the original image from its compressed counterparts. Furthermore, a preference appeared to be shown for images that have undergone low levels of compression. This preference can most likely be attributed to the ‘de‐noising’ effect of the compression algorithm at low levels.
Acquired immunodeficiency syndrome‐related primary cerebral lymphoma: Response to irradiation
Authors: Khoo Vs , Wilson Pc , Sexton Mj , Liew Kh
Published: March 2003

Acquired immunodeficiency syndrome‐related primary cerebral lymphoma (AIDS‐PCL) is uncommon. Fourteen cases of presumed AIDS‐PCL between 1986 and 1995 were reviewed retrospectively in order to characterize the natural history, and the response to radiotherapy. The median age was 38 years (range 24–65). The median interval between seropositive diagnosis of HIV and AIDS‐PCL was 28 months (range 5–113). The median duration of symptoms was 2 weeks (range 0.2–12). At presentation, the Eastern Cooperative Oncology Group performance status (PS) was PS1 (2/14 patients), PS2 (6/14) and PS3 (6/14). The symptoms and signs were non‐specific and depended on the site and extent of cerebral involvement. There was no characteristic pattern of brain imaging in terms of size, number, location or pattern of contrast enhancement of the cerebral lesions. Nine patients received various fractionation‐dose schedules (range 8–50 Gy). Complete and partial responses were seen in 2/9 and 3/9 cases, respectively. Clinical stabilization of neurological symptoms was noted in 3/9 cases and disease progression in 1/9. The median survival times (MST) from presentation for irradiated and non‐irradiated patients were 9.3 and 2.1 weeks, respectively (range 0.9–43.1). Although patient selection introduced bias, there appears to be a modest improvement in MST for treated patients. The MST with radiotherapy alone remains poor, but radiotherapy may provide palliation. For some selected patients, a prolonged response is possible.
Clinical application of in vitro radiohypersensitivity testing
Authors: Christie David , Lavin Martin , Tan Leong
Published: March 2003

The cases of two patients who suffered severe late effects of radiotherapy are reported; each tested positive for elevated in vitro radiohypersensitivity (RHS) but negative for the ataxia–telangiectasia mutation. The first patient underwent surgery and postoperative radiotherapy for lung cancer and subsequently developed fatal myelopathy. The second patient underwent triple‐modality therapy for cervical cancer and suffered highly symptomatic pelvic fibrosis. The value of the testing was that it increased the confidence in the diagnosis of radiation effects and enabled suitable treatment to proceed. An increasing role for clinical RHS testing is anticipated.
Primary empty sella turcica: A radiological– anatomical correlation
Authors: Sage Michael R , Blumbergs Peter C
Published: March 2003

The anatomical basis of the primary empty sella turcica is illustrated to emphasize that it represents a normal variant and not pathology.
Alternative uses for the haemostatic vascular sheath
Authors: Snow Thomas M , O’Connell Timothy B
Published: March 2003

The haemostatic vascular sheath has several non‐vascular applications in interventional radiology. It is used to preserve access to an organ (i.e. contrast can be introduced without removing catheters and guidewires). There are also advantages regarding patient comfort and safety. Three such applications are described.
Use of digitally reconstructed radiographs in radiotherapy treatment planning and verification
Authors: Yang Charles , Guiney Michael , Hughes Peter , Leung Samuel , Liew Kuen Hoe , Matar James , Quong George
Published: March 2003

The authors present 3 years of experience in using digitally reconstructed radiographs (DRR) for radiotherapy planning and verification. Comparison is made with simulation film (SF), to illustrate the advantages of DRR over SF. Emphasis is placed on using the appropriate equipment and applying the correct technique. A brief discourse on the principle of CT imaging is presented to illustrate the operation of CT software and optimization of image display for axial slices and DRR. Emphasis is placed on the application of clinical knowledge to enhance the usefulness, as well as the technical quality, of the DRR. Illustrative examples are given.
Soft tissue uptake on 99mTc methylene diphosphonate bone scan imaging: Pictorial review
Authors: Kaye J , Hayward Mike
Published: March 2003

99mTechnetium methylene diphosphonate (MDP) bone isotope may accumulate in many extra‐osseous sites due to a variety of both benign and malignant conditions. This finding on a bone scan can be crucial to the diagnosis and may not be apparent in other imaging or the clinical evaluation of the patient. We present a pictorial review sampling some of the many causes of extra‐osseous 99mTc MDP accumulation.
Parotid lymph‐node metastases from cutaneous squamous‐cell carcinomas: Treatment outcome and prognostic factors following surgery and adjuvant radiotherapy
Authors: Chua Margaret S‐T , Veness Michael J , Morgan Gary , Shakespeare Thomas , Hehir Andrew , Gebski Val , Cakir Burcu , Tiver Kenneth W
Published: March 2003

Australia has the highest incidence of cutaneous squamous cell carcinoma (SCC) in the world. The majority of lesions occur in the head and neck, and regional lymph‐node metastases from cutaneous SCCs, though uncommon, reflect an aggressive manifestation. Surgery and adjuvant radiotherapy are currently considered best practice. Fifty‐two eligible patients during 1980–1997 were identified in a retrospective review of patients treated within the department of Radiation Oncology, Westmead Hospital, Sydney. Relevant data were extracted from the files, referring clinicians and the New South Wales Cancer Council. The median age at diagnosis was 63 years and the majority were men (87%). Unfavourable pathological features were present in many of the patients. Only extranodal spread (P = 0.02) was identified as an independent predictor for locoregional recurrence on multivariate analysis. The cumulative locoregional recurrence rates were 28 and 45% at 2 and 5 years, respectively. The 5‐year cause‐specific survival rate in this study was 65%. We conclude that parotid lymph‐node metastases from cutaneous SCCs of the head and neck are associated with a high rate of locoregional recurrence and cause‐specific mortality despite surgery and adjuvant radiotherapy. The role of altered fractionation after surgery as a means to further enhance locoregional control warrants further investigation.
Three‐dimensional gadolinium‐enhanced magnetic resonance angiography of pulmonary arteriovenous malformation
Authors: Puvaneswary M
Published: March 2003

Pulmonary arteriovenous malformations (AVMs) are rare vascular malformations of the lung. Although most patients are asymptomatic, AVMs can bleed and result in haemoptysis and haemothorax. We describes a case of pulmonary AVMs in a patient with Osler–Weber–Rendu syndrome with 3‐D contrast‐enhanced MR angiography. Magnetic resonance angiography provided accurately and non‐invasively the number and size of the feeding arteries and draining veins.
ROLE OF ANDROGENS IN MEDIATING HYPERTENSION AND RENAL INJURY
Authors: Reckelhoff Jane F , Granger Joey P
Published: March 2003

1. Men are generally at greater risk for cardiovascular disease than are women, particularly with regard to enhanced progression of hypertension and loss of renal function. Despite these gender differences in the progression of hypertension and renal disease in humans and animals, the mechanisms responsible are unknown.

2. Castration in males has been shown to slow the progression of hypertension and ameliorate the loss in renal function. When serum testosterone was measured in the developing male spontaneously hypertensive rat (SHR), the peak serum testosterone level at 12 weeks coincided with the time when differences in systolic blood pressure could be measured between intact male SHR and females or castrated male SHR. Ovariectomy does not affect blood pressure in female SHR but testosterone treatment of ovariectomized females for 5 weeks results in exacerbation of hypertension almost to the level found in intact male SHR. These data strongly suggest a role for androgens in mediating the gender differences in hypertension.

3. The mechanisms by which androgens could increase blood pressure are not known. We have recently shown that, at comparable renal perfusion pressures, there is a hypertensive shift in the pressure–natriuresis relationship in male SHR compared with females or castrated male SHR. Testosterone treatment of ovariectomized female SHR also causes a rightward shift in the pressure–natriuresis relationship.

4. We hypothesize that androgens increase arterial pressure by causing a hypertensive shift in the pressure–natriuresis relationship, either by having a direct effect to increase proximal tubular reabsorption or by activation of the renin–angiotensin system. We also hypothesize that the enhanced proximal tubular reabsorption leads to a tubuloglomerular feedback‐mediated afferent vasodilation, which, in combination with the increase in arterial pressure, results in glomerular hypertension and renal injury.
EFFECT OF CHRONIC K+ DEFICIENCY ON CONTRACTILE PROPERTIES OF SOLEUS MUSCLE IN RATS: EVIDENCE OF SEX DIFFERENCES
Authors: Piyachaturawat Pawinee , Muchimapura Suparporn , Sophasan Samaisukh , Jariyawat Surawat , Pholpramool Chumpol , Satayavivad Jutamaad , Endou Hitoshi
Published: March 2003

1. Alterations in skeletal muscle function of chronically K+‐depleted male and female rats were investigated in isolated soleus muscles.

2. By 16 weeks K+ deficiency, plasma K+ concentrations in both male and female rats were reduced to approximately 2 mEq/L, which was accompanied by an approximate 50% reduction in muscle K+ content and a marked increase in muscle Na+ content. These changes were similar in both males and females.

3. Plasma creatine phosphokinase activity progressively increased with time in K+‐depleted male rats, whereas only a slight increase was observed in female rats.

4. Maximum isometric twitch tension (Pt) and tetanic tension (Po) of K+‐depleted soleus muscles from male rats was markedly suppressed; this was not seen for soleus muscles obtained from female rats.

5. After exposure to insulin in low‐K+ solution, the contractile tension of soleus from the K+‐depleted male rats was suppressed to a greater extent.

6. All alterations in muscle function during chronic K+ depletion were restored to normal after 2 weeks K+ repletion.

7. The results suggest that there is a preponderance for male over female rats in developing alterations in skeletal muscle function during chronic K+ deficiency. The changes may be associated with abnormalities of muscle membrane permeability and cellular function.
PHARMACOLOGICAL PROFILE OF ORALLY ADMINISTERED YM087, A VASOPRESSIN ANTAGONIST, IN CONSCIOUS RATS
Authors: Tomura Yuichi , Tahara Atsuo , Tsukada Junko , Yatsu Takeyuki , Uchida Wataru , Honda Yuichi Iizumi and Kazuo
Published: March 2003

1. YM087 is a newly synthesized non‐peptide arginine vasopressin (AVP) antagonist that shows high affinity for both V1A and V2 receptors. In the present study, the V1A and V2 receptor antagonist effects of orally administered YM087 were assessed in conscious rats.

2. In conscious rats, orally administered YM087 (0.1, 0.3 and 1.0 mg/kg) did not affect basal blood pressure, but YM087 dose‐dependently inhibited 30 mU/kg, i.v., AVP‐induced pressor responses. This inhibition lasted for over 8 h following the oral administration of the highest dose of YM087 (1 mg/kg).

3. In rats deprived of water and food for 16–18 h, oral administration of YM087 (0.1, 0.3, 1 and 3 mg/kg) dose‐dependently increased urine volume and reduced urine osmolality, with associated increases in urinary sodium and potassium excretion. However, these increases in electrolyte excretion were lower than those seen at comparable diuretic doses of furosemide (3, 10, 30 and 100 mg/kg, p.o.).

4. Oral administration of YM087 (0.3, 1 and 3 mg/kg) produced a dose‐dependent increase in urine volume in rats allowed free access to water, with the diuretic effect peaking 2–4 h post‐dosing at all dose levels. The diuretic effect of YM087 was sustained 8–10 h after a dose of 3 mg/kg; this is in contrast with the transient diuresis seen after furosemide (100 mg/kg, p.o.) dosing.

5. The present results demonstrate that YM087 is an orally active AVP antagonist with potent and long‐lasting effects. YM087 suppressed V1A receptor‐mediated pressor responses to AVP with minimal effects on basal haemodynamics and exerted a diuretic effect without increased electrolyte excretion by inhibiting V2 receptor‐mediated water reabsorption.
EXAMINATION OF ADENOSINE RECEPTOR‐MEDIATED RELAXATION OF THE PIG CORONARY ARTERY
Authors: Lew Michael J , Kao Sheau W
Published: March 2003

1. The adenosine receptors mediating relaxation of porcine isolated left anterior descending coronary arteries (LAD) and the effects of the level and type of preconstriction on the responses to adenosine analogues were examined in the present study.

2. Relaxation responses to the non‐selective adenosine receptor agonist N‐ethylcarboxamidoadenosine (NECA) were endothelium independent. N‐Ethylcarboxamidoadenosine, GR 79236 (A1 receptor selective) and 8‐cyclopentyl‐1,3‐dipropylxanthine (CGS 21680) (A2A receptor selective) produced full relaxation in LAD precontracted to 50% of the response to potassium depolarization with the thromboxane receptor agonist U46619. The order of potency was CGS 21680 = NECA > GR 79236, consistent with that defining the A2A receptor subtype.

3. 3,7‐Dimethyl‐1‐propargylxanthine (DMPX; A2 receptor selective) competitively antagonized NECA and CGS 21680 with pKB values of 4.95±0.09 and 5.06±0.22, respectively. The A1 receptor selective antagonist 1,3‐[3H]‐dipropyl‐8‐cyclopentylxanthine (DPCPX) had no effect on NECA relaxation, even in the presence of DMPX.

4. The sensitivity to relaxation by NECA was dependent on the precontracting agent. Arteries precontracted with endothelin (ET)‐1 were most sensitive to NECA, U46619‐precontracted arteries were intermediate and KCl‐precontracted arteries were least sensitive.

5. The potency of NECA was reduced when the preconstriction level was increased from 50 to 90% of maximum in U46619‐precontracted arteries (pEC50 7.94±0.12 and 7.35±0.04, respectively) and, in KCl‐precontracted arteries, both the potency and maximum effect of NECA were reduced when the preconstriction level increased from 50 to 80% of maximum (pEC50 7.52±0.13 and 6.91±0.26, respectively; maximum responses 82.5±10.2 and 23.9±3.6%, respectively, of the preconstricted tone). Relaxation responses to NECA were independent of the level of precontraction in ET‐1‐precontracted arteries.

6. In porcine LAD, relaxation responses to adenosine analogues were endothelium independent and were mediated via A2A adenosine receptors. Responses to NECA were dependent on both the level and type of preconstriction.
PHYSIOLOGICAL GENETICS: APPLICATION TO HYPERTENSION RESEARCH
Authors: Jacob Howard J
Published: March 2003

1. The rapid advancement of the human genome within the next 5–7 years begins a new era for biological research. The structure of all ~100 000 genes will be known, but the function of the majority of these genes will remain unknown. This paper outlines a ‘physiological genetics’ strategy for determining the genetic basis of hypertension by combining a variety of techniques (e.g. genetics, molecular biology, bioinformatics and physiology), to help identify gene function and the pathways involved in the development of hypertension in the rat.

2. Using comparative gene mapping, these regions can be used to implicate susceptibility loci for hypertension in humans, resulting in rapid conversion of basic research in animal models to relevant clinical assessment. The present study outlines some new strategies (i.e. whole‐animal physiological genetics) as a means to study disease aetiology in polygenic disorders and to facilitate gene identification in the ascent of functional genomics.
RENAL NERVE AND α2‐ADRENERGIC ACTION DURING ACUTE VOLUME EXPANSION IN THE ANAESTHETIZED RAT
Authors: Young Paul J , Miller John H
Published: March 2003

1. The effects of renal denervation and α2‐adrenoceptor blockade on diuresis and natriuresis in response to acute volume expansion (VE) were investigated in anaesthetized rats.

2. In normal rats, a 30 min intravascular VE of up to 7.5% of bodyweight caused a significant diuresis and natriuresis.

3. Denervation enhanced the diuretic effect of VE by 39%, while α2 blockade by 12 μmol/kg per h rauwolscine significantly inhibited the response by 61% in innervated kidneys and 43% in denervated kidneys.

4. Similar results were found for natriuresis in both innervated and denervated kidneys.

5. The results demonstrate that renal sympathetic nerve activity inhibits part of the increase in sodium and water excretion caused by VE, since denervation increased excretion under these conditions. The contribution of renal nerves to the control of renal function, however, decreases during the response to VE.

6. α2‐Adrenoceptor action enhanced the diuretic and natriuretic effects of VE by mechanisms otherwise unrelated to renal nerve activity.
MUSCLE VENOUS PO2 AND V.O2 ARE LINEARLY RELATED IN REPETITIVE TETANIC CONTRACTIONS OF CANINE MUSCLE DURING HYPOXIC HYPOXIA
Authors: Kohzuki H , Misawa H , Kishi T , Ohga Y , Sakata S , Takaki M
Published: March 2003

1. It has previously been shown that perfusion with high O2‐affinity‐erythrocytes decreases venous PO2 (PVO2) and decreases O2 uptake (V.O2) in contracting muscle at the same O2 delivery (arterial O2 concentration × flow). A linear V.O2–PVO2 relationship has been obtained with a V.O2‐axis intercept, suggesting that, during this type of hypoxia, V.O2 is composed of a PVO2‐dependent and ‐independent V.O2. However, the V.O2– PVO2 relation during hypoxic hypoxia has not been examined.

2. To clarify this relation, PVO2 and V.O2 have been measured in contracting gastrocnemius (1 Hz trains of 0.2 s isometric tetani) under both normoxic and hypoxic conditions during 5 min of stimulation.

3. Venous O2 changes proportionally with O2 delivery. Each V.O2–PVO2 relation was linear, with the mean described by the equation V.O2 = 5.06 + 0.41 × PVO2 (n = 6, r = 0.81, P < 0.05). The V.O2‐axis intercept was significantly different from zero (P < 0.05).

4. These results were similar to those obtained during hypoxia induced by high O2‐affinity‐erythrocytes. We conclude that there is a linear relationship between PVO2 and V.O2 above the V.O2‐axis intercept, regardless of the type of hypoxia.
Molecular Control Of Cell Type Diversity In The Developing Spinal Cord
Authors: Yamada Toshiya , Karunaratne Asanka , Hargrave Murray
Published: March 2003

1. During embryonic development, a diverse array of neurons and glia are generated at specific positions along the dorso– ventral and rostro–caudal axes of the spinal cord from a common pool of precursor cells.

2. This cell type diversity can be distinguished by the spatially and temporally coordinated expression of several transcription factors that are also linked to cell type specification at a very early stage of spinal cord development.

3. Recent studies have started to uncover that the generation of cell type diversity in the developing spinal cord. Moreover, distinct cell types in the spinal cord appear to be determined by the spatially and temporally coordinated expression of transcription factors.

4. The expression of these factors also appears to be controlled by gradients of factors expressed by ventral and dorsal midline cells, namely Sonic hedgehog and members of the transforming growth factor‐β family.

5. Changes in the competence of precursor cells and local cell interactions may also play important roles in cell type specification within the developing spinal cord.
Regulation Of Spinal Motoneuron Differentiation By The Combined Action Of Sonic Hedgehog And Neurotrophin 3
Authors: Dutton Renée , Yamada Toshiya , Turnley Ann , Bartlett Perry F , Murphy Mark
Published: March 2003

1. The development of ventral cell types in the spinal cord, including motor neurons, requires the growth factor Sonic hedgehog (Shh). However, it is still unknown whether Shh acts directly on precursors to induce these cell types and whether additional factors are required for induction.

2. To further investigate the precise role of Shh in spinal motoneuron development, we used low‐density cultures of murine spinal cord precursor cells.

3. Although purified Shh stimulated neuronal differentiation, it did not increase the proportion of neurons expressing the motoneuron marker Islet‐1 (Isl‐1). In contrast, purified Shh induced Isl‐1 expression in neural tube explants, suggesting that additional neural tube‐derived factors are required to induce motoneuron differentiation.

4. A factor implicated in motoneuron development, neurotrophin 3 (NT3), had no effect on Isl‐1 expression; however, in combination with Shh, it induced Isl‐1 expression in the majority of neurons in the low‐density cultures. Furthermore, in explant cultures, Shh‐induced Isl‐1 expression was blocked by an anti‐NT3 antibody.

5. In addition, previous studies have shown expression of NT3 in the region of motoneuron differentiation and the loss of spinal fusimotor neurons in NT3‐knockout animals.

6. Taken together, these findings suggest that Shh can act directly on spinal cord precursors to promote neuronal differentiation, but induction of Isl‐1 expression and motor differentiation requires additional factors, including NT3.
Effect Of Glucose Load On The Transport Kinetics Of Palmitic Acid In The Human Placenta: An In Vitro Study
Authors: Nandakumaran M , Al‐Rayyes S , Al‐Yatama M , Sugathan Tn
Published: March 2003

1. A paucity of data relating to free fatty acid (FFA) transport in the human placenta in non‐steady state conditions prompted us to undertake the present study.

2. The transport kinetics of palmitic acid in non‐steady state conditions have been investigated in vitro using human perfused placental lobules. The effects of varying glucose concentrations on maternal–foetal transport of the FFA were also investigated to mimic the hyperglycaemic states of human diabetic pregnancies.

3. National Cancer Tissue Culture medium diluted with Earle’s buffered salt solution was used as the perfusate. [14C]‐Palmitic acid, along with tritiated water as a reference, was injected as a bolus into the maternal arterial perfusate and perfusate samples were collected from the venous outflow for a period of 5 min.

4. The transport fraction (TF) of palmitic acid, expressed as percentage of the injected bolus, averaged 3.45±0.15% in five perfusions, representing 9.2±1.3% of the corresponding reference marker TF. Kinetic parameters, as well as TF indices of palmitic acid expressed in relation to the reference substance, did not differ significantly between perfusions with a physiological glucose load and those with hyperglycaemic concentrations of glucose of 27.8 and 55.6 mmol/L.

5. The present study shows that hyperglycaemia per se does not significantly alter palmitic acid transport kinetics in vitro in the human perfused placental lobule.
EFFECTS OF BILATERAL NEPHRECTOMY AND ANGIOTENSIN II REPLACEMENT ON BODY FLUIDS IN FOETAL SHEEP
Authors: Gibson KAREN J , Lumbers EUGENIE R
Published: March 2003

1. To determine the importance of the kidneys in maintaining the normal volume and composition of foetal body fluids, measurements were made in 11 chronically catheterized foetuses (123–136 days) that had been bilaterally nephrectomized at least 5 days previously and compared with 10 intact foetuses (121–133 days).

2. The nephrectomized foetuses had reduced extracellular (ECV), blood, plasma and interstitial volumes per kg foetal weight (P < 0.005), reduced plasma chloride levels (P < 0.001) and were acidaemic, hypoxaemic and hypercapnaemic (P < 0.05) compared with intact foetuses. They also had reduced lung liquid production (P < 0.05) and reduced lung liquid sodium and osmolality levels (P < 0.05). Their arterial pressure was more variable between foetuses (P < 0.005) and was directly related to ECV/kg (P = 0.013).

3. To determine which of these changes were due to absence of the foetal renin–angiotensin system, seven chronically catheterized nephrectomized foetal sheep (124–132 days) were infused with replacement doses of angiotensin (Ang)II (1.5 μg/kg per h) for 3 days. Six nephrectomized foetuses were infused with 0.15 mol/L saline.

4. The AngII infusion was non‐pressor. It prevented the fall in ECV that occurred in the control group (P < 0.05) and foetal plasma chloride concentration rose (P < 0.05). Blood gas status and lung liquid production rate did not change, but lung liquid sodium concentration fell (P < 0.05) and potassium concentration rose (P < 0.05).

5. Bolus injections of AngII (0.3–5 μg) were given to assess vascular sensitivity to AngII. This was not altered by either nephrectomy or AngII replacement.

6. It is concluded that the foetal kidneys are important for the maintenance of the normal volume and composition of foetal body fluids. Angiotensin II, perhaps because it promotes fluid transfer across the placenta, helps maintain foetal ECV and plasma chloride levels.