bluuebunny/crossref_metadata_2025 huggingface dataset:
Occupational therapists’ perception of usage of information and communication technology (ICT) in Western Australia and the association of availability of ICT on recruitment and retention of therapists working in rural areas
Authors: Taylor Richard , Lee Hoe
Published: March 2005

Objective:  The purpose of this study was to investigate occupational therapists’ usage of information and communication technology (ICT) in Western Australia and the association of availability of ICT on recruitment and retention of rural therapists.

Methods:  One thousand, one hundred and thirty‐eight surveys were sent to all occupational therapists registered with the Western Australian Occupational Therapy Registration Board in January 2003. The survey was used to identify ICT access, support and literacy. The attitude of therapists towards using ICT as a communication tool and therapists’ usage patterns of ICT in metropolitan and rural localities were analysed by using the Chi‐squared test.

Results:  Email and the personal computer were used most frequently. On ICT global competency, 58% of therapists rated their competency level as good or better. Competence was rated lower for web searching (48.5%) and searching for electronic articles (29.8%). Approximately one‐third of respondents were dissatisfied with the level of technical support available and only 38.4% of therapists had participated in basic computer training provided by their current employer. Rural therapists had less access to a computer in their work environments in comparison to their metropolitan peers (P < 0.05). Nevertheless, rural therapists were using email, teleconferencing and videoconferencing more frequently than their metropolitan counterparts.

A proportion of rural therapists (45.5%) felt that ICT influenced their decision to continue working in rural areas.

Discussion and Conclusion:  Professional isolation has been cited as an inhibitor to recruit and retain health‐care workers in rural areas. The higher ICT usage by rural therapists may represent the utility of ICT as a means of circumventing professional isolation that is inherent in rural and remote areas.
Experience of spirituality, mental illness and occupation: A life‐sustaining phenomenon
Authors: Wilding Clare , May Esther , Muir‐Cochrane Eimear
Published: March 2005

Background and Aim:  This article provides an overview of a phenomenological investigation of spirituality with six people who have experienced mental illness. The study aimed to gain a greater understanding of the phenomenon of spirituality and its relationships to occupation and the experience of mental illness.

Methods and Results:  Participants were interviewed and the interviews were audiotaped and transcribed verbatim. Findings emerged through multiple readings and gradually constructed meanings from the data. Spirituality was found to be: unique to each participant, a journey through life, vitally important to participants, manifested as ‘spiritual occupations’, the foundation of meaningful doing, important socially as well as individually, and was found to support participants in coping with mental illness. This article focuses on the ‘meta’, integrative theme of spirituality as life sustaining. It concludes with the notion that spirituality is essential to the participants and is a significant aspect of their occupational behaviour.

Conclusion:  It is recommended that occupational therapists give themselves a ‘licence’ to discuss spirituality in practice and that they commit to learning more about how spirituality is a part of the lives of their clients.
Catastrophic antiphospholipid syndrome: A rare cause of disseminated microvascular thrombotic injury – a case report with pathological and molecular correlative studies
Authors: Lai Syeling , Walker David H. , Elghetany M. Tarek
Published: March 2005

Catastrophic antiphospholipid syndrome (CAPS) is a severe and rare variant of antiphospholipid syndrome (APS) characterized by acute multiorgan failure due to small vessel thrombi in patients with positive antiphospholipid antibodies. We report a fatal case of catastrophic antiphospholipid syndrome in a young woman with a history of polymyositis and Hodgkin lymphoma. The patient was admitted to hospital because of severe foot pain following several weeks of skin ulcerations. Doppler ultrasonography showed evidence of arterial ischemia of the both lower extremities. Despite anticoagulation, immunosuppression, plasmapheresis and antibiotic therapy, she developed cutaneous gangrene, retroperitoneal hematoma, ileus, and acute respiratory and renal failure that resulted in death. Autopsy showed multifocal vascular injury and microthrombi with associated hemorrhages and infarcts in multiple organs. The patient had normal levels of functional protein C and protein S and a normal level of plasma homocysteine. Tests for common thromophilic gene mutations including prothrombin 20210, factor V Leiden 1691, and methylene tetrahydrofolate reductase 677 were negative. To our knowledge, this is the first CAPS patient with molecular studies for genetic prothrombotic mutations. Our report showed that there was no association between the development of CAPS and inherited thromophilia.
Increased norepinephrine‐associated adrenomedullary inclusions in Parkinson's disease
Authors: Sugie Masayuki , Goto Jun , Kawamura Mitsuru , Ota Hidekazu
Published: March 2005

The association with Parkinson's disease (PD) of adrenomedullary inclusions, known as ‘hyaline globules’ or ‘adrenal bodies’, has been reported for over 35 years. However, the common perception has been that adrenomedullary chromaffin cells cannot be recognized as pathological cells in PD. In the present study, we discovered that the number of adrenomedullary inclusions per unit area of the adrenal medulla was larger in PD and other Lewy body disorders (LBD) than in other neurological diseases and controls without any autonomic dysfunctions, and correlated with the duration of LBD. We also showed that the cells with adrenomedullary inclusions are all norepinephrine‐secreting chromaffin cells. This was detected by PAS reaction following peroxidase immunohistochemistry of four proteins: chromogranin A, phenylethanolamine N‐methyltransferase, S‐100 protein and neurofilament protein. We also proved that the components of adrenomedullary inclusions are immunocytochemically different from those of Lewy bodies and Lewy‐related neurites, as adrenomedullary inclusions were immunonegative to ubiquitin and α‐synuclein as well as to the above four proteins. Therefore, contrary to current opinion, the norepinephrine‐secreting adrenomedullary chromaffin cell is indeed another type of pathological cell in PD and other LBD.
Soft‐tissue angiomatosis in adulthood: A case in the forearm showing a prominent myxoid adipose tissue component mimicking liposarcoma
Authors: Val‐Bernal J. Fernando , Martino María , Garcés Carlos M. , Garijo M. Francisca
Published: March 2005

Soft‐tissue angiomatosis is a rare condition characterized by diffuse proliferation of benign vascular structures, accompanied by mature adipose tissue, which affect a large segment of the body in a contiguous fashion. Most patients present in childhood or adolescence. We report a case of large soft‐tissue angiomatosis, located in the left forearm of a 65‐year‐old man, which showed extensive intramuscular and intermuscular infiltration, and embracement of the radius and the main vascular and neural bundles of the forearm. Due to the deep location, large size, ill‐defined limits and non‐homogeneous composition with areas suggestive of an adipose component in the radiological examination, the lesion raised the possibility clinically of a liposarcoma. The myxoid adipose tissue component of the lesion, a feature previously undescribed, and the predominance of small, capillary‐sized vessels were considered concordant with the clinical diagnosis. This presentation is rare. The features of the lesion made complete surgical excision impossible and amputation of the extremity was considered the best treatment. The main differential diagnoses include infiltrating lipoma, myxolipoma, angiomyxolipoma, angiolipoma, intramuscular angioma, liposarcoma and low‐grade myxofibrosarcoma. In conclusion, angiomatosis might simulate liposarcoma, particularly if the mass is large, heterogeneous, myxoid and appears later in life.
Colonic lipoma with florid vascular proliferation and nodule‐aggregating appearance related to repeated intussusception
Authors: Adachi Shiro , Hamano Rie , Shibata Kunitaka , Yoshida Shigeyuki , Tateishi Hideo , Kobayashi Tetsuro , Hanada Masato
Published: March 2005

A unique case of repeatedly intussuscepted colonic lipoma mimicking an epithelial tumor in a 50‐year‐old man is reported. The tumor was located in the ascending colon and was approximately 5 cm in diameter. Colonoscopic and barium‐enema examinations suggested a huge epithelial tumor because of its nodule‐aggregating appearance. In contrast, computed tomography examination showed a fatty element in the core of the lesion. The biopsy specimens suggested a primary angiomatous lesion because of its pronounced vascular proliferation. Because the presumed diagnoses based on the examinations were different, the preoperative diagnosis was not confirmed. The tumor was composed of intramural lipoma with a multiple polypoid mucosa overlay. This lesion was unique in that the lipoma appeared to be within the muscularis propria and the multiple polypoid appearance of its covering mucosa. The mucosal changes including florid vascular proliferation, fibromuscular obliteration and epithelial regeneration suggested a reparative process, with ischemic damage due to the effects of intussusception being the most likely event. It should be kept in mind that even a simple lipoma can have a unique appearance reminiscent of epithelial tumor when it repeatedly experiences intussusception.
Clear cell type of renal cell carcinoma with numerous hyaline globules: A diagnostic pitfall
Authors: Hes Ondrej , Benakova Katarina , Vanecek Tomas , Sima Radek , Michal Michal
Published: March 2005

A unique and never‐before‐published example of clear cell renal cell carcinoma (CRCC) found among 9000 primary renal cell tumors is presented. The tumor contained such a dense concentration of glassy hyaline globules (GHG) in the cytoplasm of the neoplastic cells that it overshadowed the morphology of the neoplasm. The resulting appearance of the tumor was quite misleading and different from the conventional CRCC. The GHG were 7–30 µm in diameter. They were glassy and pale to slightly eosinophilic in color in hematoxylin–eosin. The GHG stained positively with periodic acid–Schiff and negatively with silver and Hale's colloidal iron. Immunohistochemically, they were also negative for anti Mycobacterium bovis antigen. At the ultrastructural level, the GHG were formed by an amorphous mass of stellate shape. The GHG were localized within rough endoplasmic reticulum. Molecular genetically, mutation of the distal part of exon 3 of the VHL gene causing elongation of the VHL protein was found in the tumor, thus confirming the diagnosis of CRCC.
Evolution of management for Budd–Chiari syndrome: a team's view from 2564 patients
Authors: Wang Zhong Gao , Zhang Feng Ji , Yi Meng Qing , Qiang Li Xiao
Published: March 2005

Aim:  Exploring the development of therapy for a formerly rare and life‐threatening disorder, Budd−Chiari syndrome (BCS).

Methods:  From 1981 to 2003, 2677 patients with BCS were admitted including 2546 cases that underwent intervention. Therapeutic means included 170 membranotomies, 181 cavoatrial shunts, 312 mesoatrial shunts including mesocavoatrial shunt, 67 mesojugular shunts, 232 radical resections, 1289 PTA, and 295 miscellaneous procedures.

Results:  Patients treated in the first decade had an effective rate of 77.7%, patency for various approaches was approximately 60−90% at 7 years. In our early experience, 55.7% patients underwent shunts, 26.1% had the transcardiac membranotomy and only 0.8% the interventional modality. Recently this has shifted to 16.2%, 5.2%, and 55.6%, respectively (P < 0.01). In the early phase, 11.6% of patients were classified as stage I (less clinical severity), and 28.6% patients in stage IV (most severe). In contrast, recent patients, they were 56.1% and 4.8% (P < 0.01).

Conclusion:  Chronologically, therapy has evolved from the relatively simple to the more complex (such as variety of shunts and radical correction) procedures, and finally, the interventional approaches as the main modality. However, for patients with type II (long segment occlusion in the inferior vena cava), major procedures maintain an essential role, especially the mesocavoatrial shunt. For those with type III (the HV lesions), shunts remain the procedures of choice. This increased use of the interventional methods is a reflection of greater clinical awareness and more frequent detection of much less severe cases. In stark contrast is declining numbers of advanced cases, signalling a landmark breakthrough in the management of BCS.
Anal abscesses and fistulas
Authors: Rickard Matthew J. F. X.
Published: March 2005

Anal abscesses and fistulas are a common part of surgical practice. Most abscesses simply need to be drained and most fistulas can be safely laid open. Excessive probing should not be attempted when draining abscesses as this may lead to iatrogenic fistulas. A small percentage of fistulas are complex and very challenging to manage. Management involves an accurate diagnosis and a balance between eradication of the fistula and maintenance of continence. A decision should be made, based on clinical evaluation and anal ultrasound (if available), whether the fistula can be laid open. If it cannot be laid open, a loose seton is placed and the sepsis is allowed to settle. Once the sepsis is quiescent, a definitive repair can be attempted. There are various techniques available including rectal advancement flap, fibrin glue and cutaneous flaps all of which are discussed.
Sinus of valsalva aneurysm: surgical approaches to complicated cases
Authors: Özkara Ahmet , Çetin Gürkan , Mert Murat , Erdem Can C , Ökcün Baris , Günay Ilhan
Published: March 2005

Background:  The authors herein report surgical experience with the aneurysms of sinus of Valsalva (SVA) complicated by coexisting pathologies.

Methods:  Eight patients aged between 11 and 55 years underwent surgical repair of SVA. The aneurysms originated from the right coronary sinus in four patients, from the non‐coronary sinus in four patients and from the left in one patient (one patient had aneurysms originating from both the left and right sinuses). Six of the aneurysms were ruptured into the right atrium (n = 3), right ventricle (n = 2) and left ventricle (n = 2). Aortic insufficiency (AI; n = 3), ventricular septal defect (n = 2), atrial septal defect (n = 4), Marfan's syndrome (n = 2), pulmonary stenosis (n = 1) and aortic stenosis (n = 1) were the coexisting anomalies. Double‐chamber exposure (right atrial/ventricle and aortic) was used in all of the patients. Patch closure was preferred for defect closure. In three patients with AI, valve replacement was necessary. Two patients with endocarditis in New York Heart Association classes III−IV underwent urgent operation.

Results:  The patient with annular narrowing was the only in‐hospital death due to severe infection. The survivors were followed up for 85 months (range: 6−156 months). In two patients with Marfan's syndrome reoperation was necessary. All the surviving patients were asymptomatic with no unfavourable consequences.

Conclusions:  Although SVA can be treated successfully with low operative risk, the factors that influence patient outcome include infective endocarditis, Marfan's syndrome and the preoperative functional status of the patient.
Non‐sentinel lymph node metastases in breast cancer patients with metastatic sentinel nodes
Authors: Hung Wai‐Ka , Chan Miranda Chi‐Mui , Mak Kong‐Ling , Chong Sui‐Fan , Lau Yvonne , Ho Chiu‐Ming , Yip Andrew Wai‐Chun
Published: March 2005

Background:  Sentinel lymph node biopsy (SLNB) has been shown to be relatively accurate in axillary nodal staging in breast cancer. In more than half of the patients with metastatic sentinel lymph node (SLN), the SLN was the only lymph node involved in the axilla.

Methods:  A retrospective analysis was performed for those female Chinese breast cancer patients who underwent SLNB. All patients had axillary dissection after SLNB. Those patients with metastatic SLN were selected for analysis. Various tumour factors and SLN factors were analysed to study the association with residual lymph node metastasis.

Results:  A total of 139 SLNB was performed. The success rate of SLN localization, false negative rate and accuracy were 92%, 9% and 95%, respectively. Fifty‐five patients had metastases in the SLN. In 38 patients (69%), SLN was the only lymph node involved in the axilla. Tumours <3 cm, a single metastatic SLN, presence of micro metastases and the absence of extracapsular spread in the SLN were associated with the absence of metastasis in the non‐sentinel lymph nodes.

Conclusion:  Sentinel lymph node biopsy is accurate in the nodal staging of Chinese breast cancer patients. Several factors such as tumour <3 cm, a single metastatic SLN, micro metastases and the absence of extracapsular spread in the sentinel node(s) are useful predictors for the absence of residual disease in the axilla. With further studies and verification, these factors may prove to be important in determining which patients with metastatic SLN will require further axillary treatment. Until such information is available, axillary dissection should be performed when positive sentinel nodes are found.
Complications of transrectal versus transperineal prostate biopsy
Authors: Miller Jason , Perumalla Chandrasekhar , Heap Graeme
Published: March 2005

Background:  There are two established techniques of prostate biopsy: the more widely used transrectal technique, and the transperineal technique. Although the transrectal technique is faster, it is reported to have an increased risk of septic complications, which may be life threatening. The present study compares complication rates of both techniques at Nambour General Hospital.

Methods:  The present retrospective study was performed by reviewing all available medical charts of men who underwent prostate biopsy during the years 1996−2001. The following data were recorded in a database: date of birth; digital rectal examination findings; serum prostate specific antigen (PSA); biopsy technique; number of cores taken; number of positive cores; Gleason grade and score; complications. Results were tabulated and simple statistical analysis performed to compare both groups.

Results:  A total of 197 biopsies was included in the study, with 81 transperineal biopsies in 75 men, and 116 transrectal biopsies in 103 men. There was no statistically significant difference in complication rates, including sepsis, between transrectal biopsy and transperineal biopsy. The rate of sepsis was 1.2% for the transperineal technique, and 0% for the transrectal technique (P = 0.411, Fisher exact test). Overall complication rates were 22.2% for transperineal technique and 19.8% for transrectal technique (P = 0.773, Fisher exact test).

Conclusion:  Although the present study was limited by retrospective design and size it suggests that both techniques are equally safe. A review of medical literature supports a tranperineal approach to patients who will tolerate sepsis poorly, or who have a suspected inflammatory cause of their raised PSA.
Severe acute respiratory syndrome in surgical patients: a diagnostic dilemma
Authors: Tan Felicia Li Sher , Loo Wee Lim , Tan Seck Guan , Wong Chow Yin , Tan Yu‐Meng
Published: March 2005

Background:  The diagnosis of severe acute respiratory syndrome (SARS) in surgical patients can potentially be missed based on current World Health Organization (WHO) case definitions.

Method:  We report a retrospective case series of 10 surgical inpatients diagnosed with SARS following an outbreak in the surgical wards. Patients were included if they fulfilled the WHO case definition of probable SARS, had an active surgical problem and were admitted to the surgical wards during the outbreak period. Clinical histories, laboratory investigations and radiological findings were reviewed and analyzed.

Results:  The mean age of the cohort was 57.6 years (range: 38−78 years). Nine patients had concomitant medical conditions. Three patients were in the early postoperative period, while the remaining seven were admitted for surgical related infections. All patients presented with fever, but only eight had accompanying respiratory symptoms. Lymphopenia and raised lactate dehydrogenase (LDH) was seen in seven patients. Eight patients had positive bacterial cultures. The primary abnormality on chest radiograph was air‐space opacification. Rapid progression of radiological changes was seen in seven patients. Mortality rate for our cohort is 20%.

Conclusion:  The diagnosis of SARS in surgical patients differs from that previously described in normal patients. An apparent cause of fever and positive blood cultures cannot exclude a diagnosis of SARS. The current WHO case definition could result in delayed or even missed diagnosis. Early isolation of febrile patients with a positive contact history must be undertaken, even in the face of another identifiable cause.
Bilateral ankle blocks: A prospective audit
Authors: Rudkin Glenda E , Rudkin Adam K , Dracopoulos George C
Published: March 2005

Background:  There are significant advantages to the practice of bilateral ankle block. However, clinicians are reluctant to employ this technique due to concerns over reliability, local anaesthetic longevity and toxicity, surgical efficiency, and patient comfort.

Methods:  Sixty‐six patients undergoing bilateral ankle blocks during mid‐ and forefoot surgery were audited to determine success rate, local anaesthetic safety and efficacy, and patient acceptance. Intravenous sedation was administered both during insertion of ankle blocks and intraoperatively, as requested by the patient and as deemed necessary by the anaesthetist. The choice of local anaesthesia was either a 50/50 mixture of lignocaine 1.5% plain and ropivacaine 7.5 mg/mL, ropivacaine 7.5 mg/mL alone or ropivacaine 7.5 mg/mL and clonidine 1 µg/kg.

Results:  A total of 89% of patients had a successful bilateral ankle block. Ropivacaine and clonidine combination, ropivacaine, and ropivacaine and lignocaine combination provided a mean length of action of 17 h, 14 h and 8 h, respectively. No adverse local anaesthetic events were reported. Sixty‐one per cent of patients remembered intraoperative events; only one patient would choose not to have the procedure performed again under ankle blocks.

Conclusions:  The present audit demonstrates that bilateral ankle blocks are a safe and efficient technique. With appropriate doses of sedative drugs both during insertion of the ankle block and surgery, patients remain comfortable.
Laparoscopic live donor nephrectomy
Authors: Rao M. Mohan , Russell Christine H
Published: March 2005

Background:  The demand for renal transplants is greater than the available kidneys. Live donation is one way of increasing the supply. Laparoscopic removal of the donor kidney appears to reduce morbidity for the donors. Some who are hesitant because of the morbidity associated with open nephrectomy are willing to consider the laparoscopic donor nephrectomy.

Methods:  Laparoscopic donor nephrectomy was offered to all but three donors since the commencement of the programme in 1997. Data were collected both prospectively and retrospectively for the first 120 donors. Venous and arterial anatomy was assessed preoperatively by computed tomographic angiography.

Results:  All but four donor procedures were completed laparoscopically. Three of these were for bleeding that could not be safely controlled laparoscopically and the fourth was a planned conversion to deal with the renal vessels, in the first right nephrectomy. Two kidneys were lost due to arterial thrombosis and two underwent segmental infarction after the loss of one of two or three separately anastomosed vessels. Three recipients had delayed function and two of them required dialysis postoperatively. Other minor complications occurred but were uncommon.

Conclusions:  Laparoscopic live donor nephrectomy is safe for the donor and the transplant kidney. It offers the advantage of decreased morbidity for the donor, with a shorter hospital stay, earlier return to normal activity and, for some, early return to work.
Necrotizing fasciitis: analysis of 48 cases in South Auckland, New Zealand
Authors: Tiu Albert , Martin Richard , Vanniasingham Peter , MacCormick Andrew D. , Hill Andrew G.
Published: March 2005

Background:  To assess the presentation, management and risk factors for mortality in necrotizing fasciitis at Middlemore Hospital in South Auckland, New Zealand.

Methods:  A retrospective review of the medical records of patients presenting to Middlemore Hospital over a 6‐year period (1997−2002) with a diagnosis of necrotizing fasciitis.

Results:  Forty eight patients were identified. There were 27 men and 21 women whose age ranged from 19 to 80 years (median 51 years) at presentation. Maori and Pacific Islanders accounted for 64% of total admissions despite making up only 31% of the referral population. Streptococcus Pyogenes was the most common bacterial isolate (54%). 31% of patients had polymicrobial infections. Sixty‐two per cent of cases involved extremities. The median number of operations and length of stay were 4 and 31 days, respectively. Overall mortality was 29%. In multivariate analysis, delay in surgical intervention (P = 0.015) and diabetes mellitus (P = 0.023) were found to be associated with increased mortality. Ethnicity, sex, type of pathogen, site of infection and increasing age did not affect mortality.

Conclusion:  Necrotizing fasciitis remains a significant problem in our community especially in the Maori and Pacific population. Early surgical debridement decreases mortality rates.
Inguinal hernia repair with the Kugel patch
Authors: Reddy K. Marcus , Humphreys Wendy , Chew Andrew , Toouli James
Published: March 2005

Background:  The Kugel hernia patch (Davol, Cranston, RI, USA) for treatment of inguinal hernias is a minimal access technique of inguinal herniorrhaphy, which aims to combine the utility of the open operation with the advantages of the laparoscopic procedures. The aim of the present study is to report an initial experience of a cohort of patients with inguinal hernias undergoing repair using this technique.

Methods:  A prospective series of 107 inguinal hernia repairs performed between January 2000 and October 2003 in 96 patients, using the Bard Kugel hernia patch were entered into the study. Patient comfort, complications, activity levels postoperations and early recurrence were evaluated.

Results:  The median age was 76 years (range 23−88 years). There were 107 inguinal hernias repaired. There were 11 bilateral, 39 left and 46 right sided hernias, 12 were recurrent. There were no major complications. There were no early recurrences. At 6 and 12 months there were one and two hernia recurrences, respectively. A further recurrence was noted at 2 years. There was no consistent relationship between having hernia surgery and loss of mobility. There was no difference in straight leg raising noted following surgery compared to the patients’ preoperative score. Ability to shower, dress, reach the toilet or perform housework by day 7 returned to normal. Shopping activities were resumed by day 30 in all patients.

Conclusions:  The Kugel hernia operation is associated with minimal postoperative pain and rapid return to normal activity. There is a modest hernia recurrence rate, which needs to be addressed.
Gastrointestinal haemorrhage complicating small bowel neurofibromatosis
Authors: Appu Sree , Valentine Renata , McLaughlin Stephen
Published: March 2005

A case of acute gastrointestinal haemorrhage in a patient with systemic neurofibromatosis is presented. The bleeding was localized using mesenteric angiography and small bowel enema to a segment of ileum with multiple smooth muscle neurofibromata. The patient had a complete recovery after the resection and remained asymptomatic at 2 years follow up. Small bowel neurofibromatosis is a rare but important differential in gastrointestinal haemorrhage. Early diagnosis and surgery are vital for patient survival.
Seasonal pattern of shoot emergence and its endogenous control in horsenettle (Solanum carolinense L.)
Authors: MIYAZAKI KATSURA , ITO MISAKO , URAKAWA SHUJI
Published: March 2005

Controlling established horsenettle plants is achieved by suppressing shoot emergence from root systems. The seasonal pattern of shoot emergence and its possible endogenous control in horsenettle (Solanum carolinense L.) were investigated. The shoot emergence period in an undisturbed population was limited to a seven‐week period from mid‐April, and a little longer in tilled conditions. Detached roots showed very high shoot‐sprouting ability under 15–30°C throughout the year. In shoot clipping experiments, new shoots sprouted only from the stem and not from the root when attached to shoots, whether above‐ground or underground. On the contrary, new shoots sprouted from the roots when all parts of the shoots were clipped off. From these results, the limited shoot emergence period in horsenettle is thought to be initiated by temperatures necessary for sprouting and is ended by a growth correlation effect between early emerged and matured shoots.
Microcrack initiation and growth in heat‐resistant 15Kh2MFA steel under cyclic deformation
Authors: YASNIY P. V. , HLADO V. B. , HUTSAYLYUK V. B. , VUHERER T.
Published: March 2005

This paper presents the results of investigation of a nuclear reactor pressure vessel steel 15Kh2MFA of two strength levels under cyclic loading. The mechanism of microcrack formation on the surface and in the bulk of 15Kh2MFA steel under cyclic deformation was investigated. Analysis of the specimen surfaces has shown that microcracks are caused by cyclic sliding in grains most favourably oriented with respect to the direction of the maximum shear stresses. Transmission electron microscope investigations show that microcracks in the material inside the grains are formed mainly along the band‐type dislocation structure parallel to the dislocation subboundary. During cyclic deformation, the dislocation density on the subboundaries increases, in the local areas the dislocation density becomes limiting and it reaches the plasticity limit and causes microcrack formation. The interrelation of the average length of microcracks and their surface density with the energy density of inelastic deformation has been found.
Fatigue behaviour of tubular AlMgSi welded specimens subjected to bending–torsion loading
Authors: COSTA J. D. M. , ABREU L. M. P. , PINHO A. C. M. , FERREIRA J. A. M.
Published: March 2005

This paper is concerned with an experimental and numerical study of the fatigue behaviour of tubular AlMgSi welded specimens subjected to biaxial loading. In‐phase torsion–bending fatigue tests under constant amplitude loading were performed in a standard servo‐hydraulic machine with a suitable gripping system. Some tests in pure rotating bending with and without steady torsion were also performed. The influence of stress ratio R and bending–torsion stress ratio were analysed. Correlation of the fatigue lives was done using the distortion energy hypothesis (DEH), based on the local stresses and strains. The applicability of the local strain approach method to the prediction of the fatigue life of the welded tubular specimens was also investigated. Static torsion has only a slight detrimental influence on fatigue strength. The DEH (von Mises criterion) based on local stresses in the weld toes was shown to satisfactorily correlate fatigue lives for in‐phase multiaxial stress–strain states. The stress–strain field intensity predictions were shown to have less scatter and are in better agreement with the experimental results than the equivalent strain energy density approach.
A fracture mechanics and mechanistic approach to the failure of cortical bone
Authors: RITCHIE R. O. , KINNEY J. H. , KRUZIC J. J. , NALLA R. K.
Published: March 2005

The fracture of bone is a health concern of increasing significance as the population ages. It is therefore of importance to understand the mechanics and mechanisms of how bone fails, both from a perspective of outright (catastrophic) fracture and from delayed/time‐dependent (subcritical) cracking. To address this need, there have been many in vitro studies to date that have attempted to evaluate the relevant fracture and fatigue properties of human cortical bone; despite these efforts, however, a complete understanding of the mechanistic aspects of bone failure, which spans macroscopic to nanoscale dimensions, is still lacking. This paper seeks to provide an overview of the current state of knowledge of the fracture and fatigue of cortical bone, and to address these issues, whenever possible, in the context of the hierarchical structure of bone. One objective is thus to provide a mechanistic interpretation of how cortical bone fails. A second objective is to develop a framework by which fracture and fatigue results in bone can be presented. While most studies on bone fracture have relied on linear‐elastic fracture mechanics to determine a single‐value fracture toughness (e.g., Kc or Gc), more recently, it has become apparent that, as with many composites or toughened ceramics, the toughness of bone is best described in terms of a resistance‐curve (R‐curve), where the toughness is evaluated with increasing crack extension. Through the use of the R‐curve, the intrinsic and extrinsic factors affecting its toughness are separately addressed, where ‘intrinsic’ refers to the damage processes that are associated with crack growth ahead of the tip, and ‘extrinsic’ refers to the shielding mechanisms that primarily act in the crack wake. Furthermore, fatigue failure in bone is presented from both a classical fatigue life (S/N) and fatigue‐crack propagation (da/dN) perspective, the latter providing for an easier interpretation of fatigue micromechanisms. Finally, factors, such as age, species, orientation, and location, are discussed in terms of their effect on fracture and fatigue behaviour and the associated mechanisms of bone failure.
Resistance to fipronil in Drosophila simulans: influence of two point mutations in the RDL GABA receptor subunit
Authors: Le Goff Gaëlle , Hamon Alain , Bergé Jean‐Baptiste , Amichot Marcel
Published: March 2005

The Eyguières 42 strain of Drosophila simulans, obtained by laboratory selection, displayed ∼ 20 000‐fold resistance to the insecticide fipronil. Molecular cloning of the cDNA encoding the RDL GABA receptor subunit of this strain revealed the presence of two mutations: the Rdl mutation (A301G) and an additional mutation in the third transmembrane domain (T350M). In order to assess the individual and combined roles of the two mutations in fipronil resistance, the functional properties of wild‐type, A301G, T350M and A301G/T350M homomultimeric RDL receptors were compared by expression in Xenopus oocytes. In wild‐type receptors, the inhibition of GABA (EC30)‐induced currents by fipronil and picrotoxin was enhanced by repeated GABA applications. The A301G mutation nearly abolished this effect, decreased the sensitivity to fipronil and picrotoxin and increased the reversibility of inhibition. The T350M mutation also reduced the sensitivity to both antagonists. Of the four receptor variants tested, the double mutant showed the highest resistance to fipronil, following repeated GABA applications. In conclusion, the present study emphasizes new aspects of the pharmacological alterations induced by the Rdl mutation and shows that resistance to GABA receptor‐directed insecticides may implicate a mutation distinct from Rdl.
Pharmacological modulation of the endocannabinoid system in a viral model of multiple sclerosis
Authors: Mestre Leyre , Correa Fernando , Arévalo‐Martín Angel , Molina‐Holgado Eduardo , Valenti Marta , Ortar Giorgio , Di Marzo Vincenzo , Guaza Carmen
Published: March 2005

Theiler's virus infection of the central nervous system (CNS) induces an immune‐mediated demyelinating disease in susceptible mouse strains and serves as a relevant infection model for human multiple sclerosis (MS). Cannabinoids have been shown to exert beneficial effects on animal models of MS and evidence suggests that the endocannabinoid system plays a role in the tonic control of spasticity. In this study we show that OMDM1 [(R)‐N‐oleoyl‐(1′‐hydroxybenzyl)‐2′‐ethanolamine] and OMDM2 [(S)‐N‐oleoyl‐(1′‐hydroxybenzyl)‐2′‐ethanolamine], two selective inhibitors of the putative endocannabinoid transporter and hence of endocannabinoid inactivation, provide an effective therapy for Theiler murine encephalomyelitis virus‐induced demyelinating disease (TMEV‐IDD). Treatment of TMEV‐infected mice with OMDM1 and OMDM2 enhanced anandamide levels in the spinal cord and ameliorated motor symptoms. This was associated with a down‐regulation of inflammatory responses in the spinal cord. In addition we show that OMDM1 and OMDM2 down‐regulate macrophage function by (i) decreasing the surface expression of major histocompatibility complex (MHC) class II molecules, (ii) inhibiting nitric oxide synthase‐2 (NOS‐2) expression and (iii) reducing the production of the pro‐inflammatory cytokines interleukin‐1beta (IL‐1β) and interleukin‐12 (IL‐12p40). Taken together, these results point to the manipulation of the endocannabinoid system as a possible strategy to develop future MS therapeutic drugs.
Neuroprotective effects of atorvastatin against glutamate‐induced excitotoxicity in primary cortical neurones
Authors: Bösel Julian , Gandor Florin , Harms Christoph , Synowitz Michael , Harms Ulrike , Djoufack Pierre Chryso , Megow Dirk , Dirnagl Ulrich , Hörtnagl Heide , Fink Klaus B. , Endres Matthias
Published: March 2005

Statins [3‐hydroxy‐3‐methylglutaryl‐coenzyme A (HMG‐CoA) reductase inhibitors] exert cholesterol‐independent pleiotropic effects that include anti‐thrombotic, anti‐inflammatory, and anti‐oxidative properties. Here, we examined direct protective effects of atorvastatin on neurones in different cell damage models in vitro. Primary cortical neurones were pre‐treated with atorvastatin and then exposed to (i) glutamate, (ii) oxygen–glucose deprivation or (iii) several apoptosis‐inducing compounds. Atorvastatin significantly protected from glutamate‐induced excitotoxicity as evidenced by propidium iodide staining, nuclear morphology, release of lactate dehydrogenase, and mitochondrial tetrazolium metabolism, but not from oxygen–glucose deprivation or apoptotic cell death. This anti‐excitototoxic effect was evident with 2–4 days pre‐treatment but not with daily administration or shorter‐term pre‐treatment. The protective properties occurred independently of 3‐hydroxy‐3‐methylglutaryl‐CoA reductase inhibition because co‐treatment with mevalonate or other isoprenoids did not reverse or attenuate neuroprotection. Atorvastatin attenuated the glutamate‐induced increase of intracellular calcium, which was associated with a modulation of NMDA receptor function. Taken together, atorvastatin exerts specific anti‐excitotoxic effects independent of 3‐hydroxy‐3‐methylglutaryl‐CoA reductase inhibition, which has potential therapeutic implications.
Trophic factors attenuate nitric oxide mediated neuronal and axonal injuryin vitro: roles and interactions of mitogen‐activated protein kinase signalling pathways
Authors: Wilkins Alastair , Compston Alastair
Published: March 2005

Inflammation in the central nervous system occurs in diseases such as multiple sclerosis and leads to axon dysfunction and destruction. Bothin vitroandin vivoobservations have suggested an important role for nitric oxide (NO) in mediating inflammatory axonopathy. The purposes of this study were to model inflammatory axonopathyin vitroand identify modulators of the process. Rat cortical neurones were cultured and exposed to an NO‐donor plus potential protective factors. Cultures were then assessed for neuronal survival, axon survival and markers of intracellular signalling pathways. The NO‐donor produced dose‐dependent neuronal loss and a large degree of axon destruction. Oligodendrocyte conditioned medium (OCM) and insulin‐like growth factor type‐1 (IGF‐1), but not glial cell line‐derived neurotrophic factor (GDNF), improved survival of neurones exposed to NO donors. In addition p38 MAP kinase was activated by NO exposure and inhibition of p38 signalling led to neuronal and axonal survival effects. OCM and IGF‐1 (but not GDNF) reduced p38 activation in NO‐exposed cortical neurones. OCM, IGF‐1 and GDNF improved axon survival in cultures exposed to NO, a process dependent on mitogen‐activated protein kinase/extracellular signal‐related kinase signalling. This study emphasizes that different mechanisms may underlie neuronal/axonal destructive processes, and suggests that trophic factors may modulate NO‐mediated neurone/axon destruction via specific pathways.
Impaired proteasome activity and accumulation of ubiquitinated substrates in a hereditary neuropathy model
Authors: Fortun Jenny , Li Jie , Go Jocelyn , Fenstermaker Ali , Fletcher Bradley S. , Notterpek Lucia
Published: March 2005

Accumulation of misfolded proteins and alterations in the ubiquitin–proteasome pathway are associated with various neurodegenerative conditions of the CNS and PNS. Aggregates containing ubiquitin and peripheral myelin protein 22 (PMP22) have been observed in the Trembler J mouse model of Charcot‐Marie‐Tooth disease type 1A demyelinating neuropathy. In these nerves, the turnover rate of the newly synthesized PMP22 is reduced, suggesting proteasome impairment. Here we show evidence of proteasome impairment in Trembler J neuropathy samples compared with wild‐type, as measured by reduced degradation of substrate reporters. Proteasome impairment correlates with increased levels of polyubiquitinated proteins, including PMP22, and the recruitment of E1, 20S and 11S to aggresomes formed either spontaneously due to the Trembler J mutation or upon proteasome inhibition. Furthermore, myelin basic protein, an endogenous Schwann cell proteasome substrate, associates with PMP22 aggregates in affected nerves. Together, our data show that in neuropathy nerves, reduced proteasome activity is coupled with the accumulation of ubiquitinated substrates, and the recruitment of proteasomal pathway constituents to aggregates. These results provide novel insights into the mechanism by which altered degradation of Schwann cell proteins may contribute to the pathogenesis of certain PMP22 neuropathies.
Inducers of oxidative stress block ciliary neurotrophic factor activation of Jak/STAT signaling in neurons
Authors: Kaur N. , Lu B. , R.K. Monroe  , Ward S.M. , Halvorsen S.W.
Published: March 2005

Generation of reactive oxygen species (ROS) with the accumulation of oxidative damage has been implicated in neurodegenerative disease and in the degradation of nervous system function with age. Here we report that ROS inhibit the activity of ciliary neurotrophic factor (CNTF) in nerve cells. Treatment with hydrogen peroxide (H2O2) as a generator of ROS inhibited CNTF‐mediated Jak/STAT signaling in all cultured nerve cells tested, including chick ciliary ganglion neurons, chick neural retina, HMN‐1 motor neuron hybrid cells, and SH‐SY5Y and BE(2)‐C human neuroblastoma cells. H2O2 treatment of non‐neuronal cells, chick skeletal muscle and HepG2 hepatoma cells, did not inhibit Jak/STAT signaling. The H2O2 block of CNTF activity was seen at concentrations as low as 0.1 mm and within 15 min, and was reversible upon removal of H2O2 from the medium. Also, two other mediators of oxidative stress, nitric oxide and rotenone, inhibited CNTF signaling. Treatment of neurons with H2O2 and rotenone also inhibited interferon‐γ‐mediated activation of Jak/STAT1. Depleting the intracellular stores of reduced glutathione by treatment of BE(2)‐C cells with nitrofurantoin inhibited CNTF activity, whereas addition of reduced glutathione protected cells from the effects of H2O2. These results suggest that disruption of neurotrophic factor signaling by mediators of oxidative stress may contribute to the neuronal damage observed in neurodegenerative diseases and significantly affect the utility of CNTF‐like factors as therapeutic agents in preventing nerve cell death.
An adenosine A2A receptor agonist induces sleep by increasing GABA release in the tuberomammillary nucleus to inhibit histaminergic systems in rats
Authors: Hong Zong‐Yuan , Huang Zhi‐Li , Qu Wei‐Min , Eguchi Naomi , Urade Yoshihiro , Hayaishi Osamu
Published: March 2005

The adenosine A2A receptor (A2AR) has been demonstrated to play a crucial role in the regulation of the sleep process. However, the molecular mechanism of the A2AR‐mediated sleep remains to be elucidated. Here we used electroencephalogram and electromyogram recordings coupled with in vivo microdialysis to investigate the effects of an A2AR agonist, CGS21680, on sleep and on the release of histamine and GABA in the brain. In freely moving rats, CGS21680 applied to the subarachnoid space underlying the rostral basal forebrain significantly promoted sleep and inhibited histamine release in the frontal cortex. The histamine release was negatively correlated with the amount of non‐rapid eye movement sleep (r = − 0.652). In urethane‐anesthetized rats, CGS21680 inhibited histamine release in both the frontal cortex and medial pre‐optic area in a dose‐dependent manner, and increased GABA release specifically in the histaminergic tuberomammillary nucleus but not in the frontal cortex. Moreover, the CGS21680‐induced inhibition of histamine release was antagonized by perfusion of the tuberomammillary nucleus with a GABAA antagonist, picrotoxin. These results suggest that the A2AR agonist induced sleep by inhibiting the histaminergic system through increasing GABA release in the tuberomammillary nucleus.