bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal changes in and effects of familiarity on agonistic behaviors of rat‐like hamsters (Cricetulus triton)
Authors: Zhang Jian‐Xu , Zhang Zhi‐Bin , Wang Zu‐Wang
Published: March 2003

The seasonal changes in agonistic behaviors and effects of familiarity on agonistic behaviors in wild‐caught adult rat‐like hamsters (Cricetulus triton) were observed in dyadic encounters in a neutral arena. The aggression of opposite‐ and same‐sex encounters became higher or remained the same during the non‐breeding season. This indicates that the hamsters were solitary during both seasons. Familiarity increased the aggression in male–male encounters and decreased the aggression in female–female encounters during both seasons. Familiarity also increased the aggression in female–male encounters during the non‐breeding season and had no effect on the aggression in female–male encounters during the breeding season. These results may be related to the hamster’s social structure. The more agonistic acts both male and female hamsters had, the more frequently they marked using flank glands during both seasons. This implies that flank gland marking can be used to advertise status and can be assessed by opponents to reduce the agonistic costs.
Stable nitrogen and carbon isotope ratios as migration tracers of a landlocked goby, Rhinogobius sp. (the orange form), in the Lake Biwa water system
Authors: Maruyama Atsushi , Yamada Yoshihiro , Yuma Masahide , Rusuwa Bosco
Published: March 2003

Fluvial–lacustrine migrations of a landlocked goby, Rhinogobius sp. (the orange form) in the Lake Biwa water system were traced using stable nitrogen and carbon isotope ratios. The δ15N values of Rhinogobius sp. individuals in the lake were significantly higher than those of large individuals in a tributary river (≥1+ age) without overlap of the range, although there was little difference in the δ13C values between these two locations. Because these values reflected those of the corresponding prey organisms in either location, it was revealed that none of the large individuals had migrated from one location to the other. The δ15N values of the small individuals in the tributary river (0+ age) were too high to be fluvial residents. This result indicated that all of the small individuals studied had spent their larval periods in the lake, and that immigrant individuals can be distinguishable by measuring the δ15N values retaining the effect of foraging in the alternate location. We conclude that the δ15N value works as a useful tracer to clarify the fluvial–lacustrine migration pattern of the fish.
Resource‐driven terrestrial interaction webs
Authors: Price Peter W.
Published: March 2003

Terrestrial food webs based on living plants may well represent 75% of global terrestrial biodiversity. The majority of component species are specialists and a large proportion is parasitic as herbivores and carnivores, with consequences for high sensitivity to heterogeneity on a variety of scales. Relatively large primary producers support relatively small insect herbivores and carnivores, with plants providing both food and habitat, making resource‐driven effects very strong. Complexity of resources provided by plants, with influences up the food web, is generated by at least seven major factors: (i) plants as food; (ii) plants as habitat; (iii) the physical traits of plants such as size, toughness and trichomes; (iv) traits of plants that require evolutionary responses by herbivores in terms of crypsis, phenological synchrony, life history and behavioral adaptations; (v) the constitutive chemicals in plants; (vi) the induced changes in plants caused by herbivory; and (vii) landscape and biogeographic variation in vegetation types and food web richness. No other trophic level has such a wide‐ranging impact on other trophic levels. But such broad impact makes the term ‘food web’ overly narrow and inadequate. The term ‘interaction web’ is preferable, aiding recognition of the many kinds of interactions that pass up food webs from living plants. Any claim that top‐down impact is stronger than bottom‐up influences is necessarily couched in a narrow sense of biomass or numbers reduction.
Factors causing variation in flock size: Decision making to join a foraging flock
Authors: Yamaguchi Noriyuki , Yahara Tetsukazu
Published: March 2003

In order to clarify the temporal variation of flock size, we examined factors that cause the temporal variation of foraging flock size in a wintering population of the Yellow‐throated bunting (Emberiza elegans). We conducted field observations to examine whether the flock size varies greatly and whether non‐random associations between individuals exist. We confirmed that flock size varied greatly and some individuals showed non‐random associations with other flock members. Then, we carried out computer simulations that assume stochastic risky situation, the condition of hunger level and non‐random associations between individuals. In the simulation, the condition of hunger level caused the variation of flock size. However, the distribution of flock size differed from observed ones. When the condition of non‐random association was added to the simulation, the variation of flock size became large and the distribution of flock size was similar to that of the observed one. In wintering flocks of Yellow‐throated bunting, each individual attempts to forage in an optimal flock size. However, if they are extremely starved, it is suggested that they adopt a conditional strategy to join a flock independently of the flock size to acquire the energy necessary for survival. Simultaneously, they may decide to forage under the effect of non‐random association between individuals.
Importance of permafrost as a source of water for plants in east Siberian taiga
Authors: Sugimoto Atsuko , Yanagisawa Nao , Naito Daisuke , Fujita Noboru , Maximov Trofim C.
Published: March 2003

Stable oxygen isotope ratios of plant water (sap water) were observed at Spasskaya Pad experimental forest near Yakutsk, Russia in 1997–1999. The δ18O of sap water in larch trees (Larix gmelinii) decreased soon after leaf unfolding every year, indicating that snowmelt water was used in the beginning of summer. During mid to late summer, a clear difference in the water source used by plants was observed between wet summers and severe drought summers. The δ18O values of water in larch trees were high (−17.8 to −16.1‰) in August 1999 (wet summer), but low (−20.4 to −19.7‰) in August 1998 (drought summer). These results indicated that plants used rainwater during a wet summer, but meltwater from permafrost was used by plants during a drought summer. One important role of permafrost is to provide a direct source of water for plants in a severe drought summer; another role is to keep surplus water in the soil until the next summer. If this permafrost system is disturbed by future global warming, unique monotypic stands of deciduous larch trees in east Siberia might be seriously damaged in a severe drought summer.
Base mineral inflow in a remnant cool‐temperate mire ecosystem
Authors: Yabe Kazuo , Nakamura Takatoshi
Published: March 2003

Kiushitou (42°28′ N, 141°9′ E) is a lowland mire located in a residential area of northern Japan. We examined the 2‐D distribution of hydrochemical variables and their seasonal changes in relation to plant communities in an attempt to conserve the Sphagnum fen (Sphagnum subfulvum). This mire is gently sloping and the upper area consists of alder and ash forests, while the lower area is covered with fen communities. The grassy fen, Moliniopsis japonica, occurs throughout the lower area, whereas the Sphagnum fen is restricted to the southwest part of the mire. anova and canonical correspondence analysis revealed that the occurrence of Sphagnum fen is negatively correlated with Mg, Ca and electrical conductivity (EC). These variables indicated that water in the upper forest area contained a high concentration of minerals from the neighboring residential area. Seasonal changes in EC values revealed that the watercourse from a spring point in an upper corner to the lowest drainage ditch was divided into two, southwest and northeast, courses. Because the northeast‐course spring water joins mineral‐rich water flowing from a point at the upper margin, the northeast part of the lower area contains considerable Ca and Mg. In contrast, the mineral‐poor spring water flowing into the southwest part of the mire ensures the survival of the Sphagnum fen. Thus, when we stop the supply of mineral‐rich water from the upper margin the area of the Sphagnum fen will expand into the northeast part of the mire. Two‐dimensional details of the hydrochemical regime clarify the impact of mineral inflow and the expansion mechanisms of these minerals.
Testing the intermediate disturbance hypothesis on species diversity in herbaceous plant communities along a human trampling gradient using a 4‐year experiment in an old‐field
Authors: IKEDA HIROAKI
Published: March 2003

The intermediate disturbance hypothesis predicts unimodal relationships between species diversity and disturbance frequency/intensity. To test this hypothesis, species diversity in herbaceous plant communities along a human trampling gradient was investigated by conducting a 4‐year experiment in an old‐field. In general, species richness (S), the Shannon–Weiner index (H′) from plant cover data and species evenness ( J′) showed negative linear relationships with trampling frequency, in contrast to the prediction of the intermediate disturbance hypothesis. However, the significant relationships between trampling frequency and species diversity were not observed in the fourth year without J′, which showed a unimodal relationship. In all experimental years, the number of new species that colonized the plots after 1 year was small under frequent trampling, and the number of species lost from the plots was large under infrequent trampling. The relative number and the relative cover of perennial species increased as trampling frequency increased in the first and second years, but this pattern was not observed in the following years because the dominance of perennials further increased at decreasing frequencies of trampling. The similarity in the species composition and the yearly changes in species dominance indicated that trampling at higher frequencies eliminated more trampling‐intolerant species only in the early years of the experiment. These results suggest that trampling mediated early changes in species diversity patterns, but competitive interactions were more important in the later experimental years. The time lag in the effects of trampling and competition appears to be attributable to the infrequent occurrence of unimodal patterns of species diversity.
First record of lily thrips, Liothrips vaneeckei Priesner, in Australia (Thysanoptera: Phlaeothripidae)
Authors: Malipatil MB , Mound LA , Finlay KJ , Semeraro L
Published: March 2003

The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids.
Calculating food consumption in the laboratory: A formula to adjust for natural weight loss
Authors: Candy Steven G , Baker Susan C
Published: March 2003

We derive a formula for correcting the weight of food eaten by an animal for natural weight loss (or gain) of the food, such as through moisture loss and food respiration. The formula is derived using a differential equation to model the loss in fresh weight based on a constant consumption rate and assumptions about the form of the function for weight loss over time of the aliquot. The standard formula is shown to over‐estimate the weight of eaten food compared to our theoretically derived formula. This over‐estimation is negligible (< 0.2%) for moisture loss below about 10% but increases sharply to 8% when moisture loss is 50%. We illustrate the application of these two formulae using a laboratory study of consumption rate by larvae of a phytophagous insect: the Tasmanian eucalyptus leaf beetle, Chrysophtharta bimaculata (Olivier) (Coleoptera: Chrysomelidae).
The Cottage Project: Caring for the unwell homeless person
Authors: Neate Sandra L , Dent Andrew W
Published: March 2003

Abstract

Objectives: The present study aims to describe the functioning of the Cottage, to describe the demographics of the patients using the Cottage, to examine benefits conveyed to patients relating to improvements in health and accommodation circumstances and to examine cost benefits of the Cottage.

Setting: The Cottage is a six‐bed, low‐dependency residential facility adjacent to St Vincent's Hospital Melbourne, a 450‐bed inner city adult tertiary teaching hospital.

Methods: Retrospective chart analysis of 50 consecutive admissions from 1 June to 1 September 1996.

Results: Seventy‐eight per cent of patients were discharged in improved health. Eight per cent gained no health improvement. Four per cent required hospital admission and 2% required Cottage readmission. Forty‐four per cent of patients were discharged to improved accommodation circumstances and 56% were discharged to the same circumstances. The cost of a Cottage bed was $82 /day.

Conclusions: The Cottage fulfils an important, cost‐effective role in caring for the unwell homeless person.
Australian gun controls: Should more be done?
Authors: Christie Louis E
Published: March 2003

Abstract

Objectives: To examine the basic premises of gun control and the relationship linking legal firearm ownership to homicide and suicide in Australia.

Data sources/ Available data from the Australian Bureau of Statistics regarding firearms ownership,

study selection: suicide and homicide in Australia were reviewed. Medline database searches using key words of ‘firearms’, ‘homicide, statistics, trends’, ‘suicide, statistics, trends’ and ‘violence, prevention and control, statistics’ identified English language publications relating to violence prevention and/or firearms from 1966 to 1996. These papers were manually searched to identify additional references. Internet home pages of The Coalition for Gun Control, The Sporting Shooters Association of Australia, Handgun Control Inc. and The National Rifle Association were reviewed and information that could be independently validated was considered.

Results: Few papers approach the subject of violence with the same focus, limiting the ability to perform meta‐analysis or direct comparisons of data.

Conclusions: Current knowledge is inconclusive, but does not provide strong support for some existing Australian firearm control measures. Evidence suggests that further reducing the levels of firearm ownership in Australia will not cause an overall reduction in rates of homicide or suicide.
Queensland tick typhus as a cause of seizures and acute confusion
Authors: Brazil Victoria , Sowden David
Published: March 2003

Queensland tick typhus is a rickettsial disease transmitted via a tick bite. The illness is usually mild, consisting of fever, myalgia and a rash. We present the case of a severe form of the illness which manifested as seizures and acute confusion. We highlight the need to consider this disease in the critically ill patient who presents with a febrile illness and a rash, and the need to consider empirical treatment in such patients.
Facsimile to general practitioners advising of patient admission from the emergency department: Why do some patients refuse consent for transmission?
Authors: Taylor David McD , Walker Stephen T
Published: March 2003

Objective: To determine why some patients refuse consent for their general practitioner to be notified, by facsimile, of their admission to hospital from the emergency department.

Methods: Descriptive, questionnaire‐based study of patients refusing consent for general practitioner notification, over a 7 month period was performed.

Results: Forty‐eight patients (1.5%) refused consent and 47 patients completed the questionnaire. Thirty‐five patients (74.5%) did not think it was necessary for their general practitioner to know of their admission and seven patients (14.9%) did not want their general practitioner to know. No refusal was related to the mode of notification (facsimile). The patients who refused consent had no defining characteristics related to gender, general practitioner or diagnosis but tended to be young, with 31 patients (64.6%) aged under 38 years.

Conclusions: It is likely that most refusals were related to a lack of understanding of the importance of general practitioner notification, although some refusals may have reflected the patient–general practitioner relationship. Patients appeared to have confidence that their faxed information would not be misdirected or accessed by unauthorized personnel. Medico‐legal action is conceivable if non‐urgent information is faxed without patient consent. We recommend the use of facsimile notification of patient admission from the emergency department, provided that informed, signed consent is obtained.
Foreign body aspiration presenting as croup
Authors: Inglis Sandy , Studholme Tom
Published: March 2003

The differential diagnosis of airway obstruction in the paediatric population is large and in the toddler age group it includes viral croup, bacterial tracheitis, spasmodic croup, laryngeal papillomatosis, retropharyngeal abscess and foreign body aspiration. A case of airway obstruction is presented in which a diagnosis of viral croup was made and in which respiratory deterioration, nearly a week later, necessitated intubation and ventilatory support. Laryngotracheoscopy revealed foreign black material in the subglottis which was initially thought to be an inhaled foreign body but subsequently was identified histologically as stratified squamous epithelium of unknown origin. Aspiration of a foreign body is a great mimicker of viral croup.
Human immunodeficiency virus seroconversion illness in the emergency department: A review
Authors: Cannon Marianne E , McCarthy James S
Published: March 2003

Abstract

Advances in the understanding of the pathogenesis of human immunodeficiency virus (HIV) infection, in diagnostic testing, and in antiretroviral therapy have refocused attention on the HIV seroconversion illness. Preliminary studies suggest that early institution of combination therapy may significantly alter the long‐term outcome of infection. As a significant proportion of cases of acute HIV infection occur in populations frequenting emergency departments, the importance of recognition and appropriate management of patients with this syndrome is reviewed.
Acute renal failure following sodium oxalate ingestion
Authors: Hamilton Susan E , Pielage Paul J , Fassett Robert G
Published: March 2003

ABSTRACT

Sodium oxalate, once a common cause of suicide or accidental death, is now rarely encountered in clinical practice. This case report emphasises the toxicity of this readily available chemical and plant toxin and discusses the management to prevent death or renal failure.
‘The needle and the damage done’: Intra‐arterial temazepam
Authors: Eddey David P , Westcott Mark J
Published: March 2003

Intra‐arterial temazepam injection by intravenous drug abusers may be associated with vascular and metabolic complications. Patients generally present with severe pain, mottling and swelling of the limb. This can progress to tissue loss. The pathophysiology is not clearly defined, but may include direct vascular injury, as well as rhabdomyolysis. This is illustrated by two cases that presented to The Geelong and St Vincent's Hospitals, Victoria, Australia, resulting in compartment syndromes, limb ischaemia and rhabdomyolysis. Treatment consists of reducing intracompartmental pressure, attempts to re‐establish blood flow by either pharmacological or surgical methods and supportive care. Compartment syndromes and ischaemia may take hours to develop, so that prolonged observation is indicated. Evidence of raised intracompartmental pressure or limb ischaemia warrants early and aggressive intervention in order to prevent or minimize the limb‐ and life‐threatening consequences of intra‐arterial injection of temazepam.
Exercise‐associated hyponatremia: A review
Authors: Speedy Dale B , Noakes Timothy D , Schneider Claudia
Published: March 2003

This paper reviews the extensive literature on hyponatremia, a common and potentially serious complication of ultra‐distance exercise. Fluid overload is the likely aetiology. Fluid intakes are typically high in athletes who develop hyponatremia, although hyponatremia can occur with relatively modest fluid intakes. The development of fluid overload and hyponatremia in the presence of a modest fluid intake raises the possibility that athletes with this condition may have an impaired renal capacity to excrete a fluid load. The bulk of evidence favours fluid retention in the extracellular space (dilutional hyponatremia) rather than fluid remaining unabsorbed in the intestine. Female gender is an important risk factor for the development of hyponatremia. Management and prevention of exercise‐associated hyponatremia are discussed. See Commentary, page 5.
Pulse rate over pressure evaluation (ROPE) is useful in the assessment of compensated haemorrhagic shock
Authors: Ardagh Michael W , Hodgson Timothy , Shaw Leanne , Turner Duncan
Published: March 2003

Objective: To evaluate a calculation of pulse rate over pulse pressure as a method of predicting decompensation in patients with compensated haemorrhagic shock.

Methods:

A retrospective cohort study was undertaken enrolling 184 adult victims of major road trauma who were not shocked on presentation to the emergency department. A pulse rate over pressure evaluation was calculated at presentation and vital signs were observed during the first 2 h of emergency department management.

Results:

Thirty‐one patients became shocked during their first 2 h. A ROPE value of greater than 3.0 had a positive predictive value of 53% and a value less than 3.0 had a negative predictive value of 86% for the development of decompensated shock.

Conclusions:

ROPE is an easily applied and useful clinical tool with a ROPE of less than 3.0 being predictive of a patient remaining well and a ROPE of above 3.0 being predictive of the patient developing decompensated shock.
Evidence, expertise and the emergency physician: Doctors should anticipate legal reform in their expert evidence
Authors: Hitchcock Thomas
Published: March 2003

The court system is particularly dependent on expertise in science and medicine. Medical experts should be aware that their legal evidence has the potential to work against justice as there are partisan selection, financial, and adversarial pressures; and laws of evidence which allow legal evidence to be admissible without definition of its medical‐evidence base. Currently the main checks on an expert’s legal evidence are the professional integrity of the expert, and cross‐examination. However, there is good reason to expect reform of the laws of legal evidence to define objective criteria for the admissibility of scientific legal evidence. In anticipation of these reforms, emergency physicians appearing in court should address the medical‐evidence base of their legal evidence.
Indigenous suicide in Australia, New Zealand, Canada and the United States
Authors: Hunter Ernest , Harvey Desley
Published: March 2003

This paper reviews literature on self‐harm and suicide among Indigenous populations in four nations with histories of British colonization, with a more detailed exploration of patterns and primary care considerations in Australian Aboriginal and Torres Strait Islander populations. Issues of definition, under‐reporting, lack of reporting, varying coronial practices and the influence of race on investigative procedures make comparisons of suicide rates among indigenous populations problematic. However, international interpretations highlight the impact of the breakdown of cultural structures and historical processes associated with colonization. Recent studies suggest that the predisposition to suicide by vulnerable young people is influenced not only by absolute living standards but also how they view their circumstances relative to those around them. The complexity of associations with mental disorder, alcohol use and ‘meaning’ in an indigenous context are considered. Responses in terms of prevention and treatment are presented, highlighting the importance of hospital‐based practitioners as the likely first point of contact. The article concludes by outlining considerations in the primary care management of indigenous self‐harm.See Commentary, page 8.
Laparoscopic appendectomy in young female patients: Should we remove the normal‐looking appendix?
Authors: Chung Kmt , Poon M , Chick Wk , Tse Cwc , Kwok Kh , Chia Nh , Hwang Jst
Published: March 2003

Objective: This study evaluated whether a significant reduction in unnecessary appendectomies is possible by performing diagnostic laparoscopy before appendectomy in female patients of child‐bearing age, leaving behind the normal‐looking appendix.

Materials and methods: Sixty‐one consecutive female patients between the ages of 15 and 45 years with clinical diagnosis of acute appendicitis were studied prospectively. Diagnostic laparoscopy was performed to detect whether the appendix was inflamed. The appendix was then removed and the result of laparoscopic diagnosis was matched with histological diagnosis.

Results: Ten out of the 42 laparoscopically diagnosed appendicitis cases had normal appendices on histological examination. Six out of the 19 laparoscopically diagnosed normal appendices had histological evidence of appendicitis. The sensitivity of laparoscopy was 84% and the specificity was 56.5%.

Conclusions: Discrepancies existed between laparoscopic appearance and histological examination in acute appendicitis. The appendices of all those with clinically suspected appendicitis should be removed and sent for histological confirmation.
Should surgeons send all surgical specimens to the pathology laboratory?
Authors: Shiu Man‐Hei , Chan Wai‐Kong , Lee Arthur Kai‐Chung , Chan Wai‐Kong
Published: March 2003

While it is standard surgical practice to submit all surgically removed organs and tissue for pathological examination, some surgeons occasionally deem this unnecessary for common surgical conditions such as acute appendicitis, cholecystitis or thrombosed haemorrhoids. We report three cases in which a clinically unsuspected malignant tumour was diagnosed by histopathological examination in this setting. Even an experienced surgeon may miss diagnosing such a tumour if using naked‐eye examination alone. Failure to make the diagnosis of cancer may deny the patient proper radical resection of a potentially curable tumour. Surgically removed organs and tissue should be scrutinized by the surgeon and, with few exceptions, submitted for histopathological examination.

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Postoperative analgesia in children day surgery circumcision: Comparison of three methods
Authors: Mak Max Yat‐Lun , Philip Aroquiasamy Emmanuel , Cho Sai‐Cheong , Chan John Tak‐Ming
Published: March 2003

Objective: To compare three methods of postoperative analgesia in children who underwent day surgery circumcision.

Methods: One hundred and eighty‐five boys who were admitted for day surgery circumcision were randomly allocated to one of three groups. Group 1 received caudal block, group 2 received dorsal penile nerve block and group 3 received a combination of rectal diclofenac and intravenous fentanyl (RD/IVFENT). Oral paracetamol was given to relieve postoperative pain; its requirement and postoperative complications were recorded.

Results: There were no significant differences found among the three groups regarding post‐circumcision paracetamol requirements in the first 2 h and day of operation, and duration of analgesia. There was no increased wound bleeding and vomiting seen for group 3.

Conclusion: RD/IVFENT is a useful alternative to caudal block and dorsal penile nerve block for providing post‐circumcision pain relief. Also, it is easier to administer and appears safe.
The role of early endoscopic follow up after simple closure of perforated duodenal ulcer: A prospective study
Authors: Ng Enders Kwok‐Wai , Leung Wai‐Keung , To Kai‐Fai , Wong Simon Kin‐Hung , Lai Paul Bo‐San , Lau Wan‐Yee , Sung Joseph Jao‐Yiu , Chung Sydney Sheung‐Chee
Published: March 2003

Objective:

Eradication of Helicobacter pylori is effective in preventing ulcer relapse after simple repair of perforated duodenal ulcers. However, when and how the H. pylori status should be determined remains unclear. The study investigated the role of early endoscopic follow up in managing patients with simple omentopexy for duodenal ulcer perforation.

Patients and Method:

Patients below the age of 75 years who had simple repair of perforated duodenal ulcer were recruited. They were given a 4‐week course of H2 receptor antagonist upon discharge and advised to return for a follow‐up endoscopy at 8 weeks after operation. During endoscopic examination, ulcer healing and other gastroduodenal pathology were noted. Random biopsies were taken from the antrum and body of the stomach for determination of H. pylori infection.

Results:

In a 30‐month period, 112 patients were admitted with perforated duodenal ulcers. The perforation was repaired by either laparoscopic (n = 41) or open method (n = 71). Eleven patients died during hospitalization. Of the 101 patients who recovered, 16 were lost to follow up. Nine patients were considered unfit for endoscopy as a result of medical comorbidities. Among the 76 patients who attended the follow‐up endoscopy, 47 were shown to have H. pylori infection (61.8%). Active duodenal ulcers were found in 15 patients, significant erosions in five patients and severe duodenitis in seven patients. Patients infected by H. pylori had a significantly higher proportion of persistent duodenal pathology compared with the uninfected patients (23/47 vs 4/29; P = 0.003). Multivariate analysis revealed that smoking and H. pylori infection were the two independent factors predicting persistent duodenal lesions.

Conclusion:

Patients treated with simple closure for duodenal ulcer perforation are recommended to have their H. pylori status determined by early follow‐up endoscopy, and an eradication regimen should be prescribed to those who are positive for the infection.

Chinese Abstract

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Risk factors and significance of finding asymptomatic retinal emboli
Authors: Mitchell Paul , Wang Jie Jin , Smith Wayne
Published: March 2003

Purpose: To assess the prevalence rates for asymptomatic retinal emboli among both younger and older individuals, with single and multiple potential risk factors, in order to alert clinicians to the probability of finding retinal emboli in patients with varying characteristics.

Methods: In all, 3654 people aged 49–97 attending the Blue Mountains Eye Study had a detailed eye examination which included retinal photographs of the central and peripheral retinal fields. Retinal emboli were identified during masked photographic grading and definite cases were adjudicated.

Results: Retinal emboli were found in 51 subjects (1.4% of the population); these included 1.1% of people aged 49–69 years (middle‐aged subjects) and 2.0% of people aged more than 70 years (older subjects). Risk factors identified were male sex, increasing age, hypertension, current smoking, history of any vascular event (angina, myocardial infarct, stroke) or history of vascular surgery. Among middle‐aged subjects, current smoking and history of hypertension or a vascular event were significantly associated with emboli (odds ratios (OR) 2.3–3.1), while in older subjects, history of vascular surgery was related (OR 4.7). The highest prevalence of emboli (5.5%) was found in people who reported a history of hypertension and also smoked (OR 6.0). Among hypertensive men who smoked, emboli were present in 7.6%.

Conclusions: This study indicates that although asymptomatic retinal emboli are relatively infrequent in the general older population, these lesions are surprisingly common in people (particularly men) with multiple risk factors. Ophthalmologists could routinely screen for emboli and consider alerting the patients’ general practitioners to review vascular risk factors.
Invasive strains of Pseudomonas aeruginosa are able to cause epithelial cell cytotoxicity that is dependent on bacterial cell density
Authors: PhD H Zhu , Willcox Mdp
Published: March 2003

The purpose of this study was to investigate the hypothesis that quorum‐sensing systems are involved in the ability of invasive Pseudomonas aeruginosa strains to cause corneal epithelial cell death. Two invasive strains, 6294 and PAO1, were co‐cultured with human corneal epithelial cells at different bacterial concentrations (10
5, 10
7 and 10
9 CFU/mL). Cytotoxicity was measured using a cytotoxicity assay kit. The levels of autoinducer in the supernatant were examined using a reporter strain of Agrobacterium tumefaciens (A136). Protease production was also monitored. Cytotoxicity of both strains was dependent on bacterial density; a moderate to high concentration of bacterial cells (10
7 and 10
9 CFU/mL) caused 70% to 94% loss of cell variability. Cytotoxicity was significantly correlated with enhanced autoinducer and protease production (r > 0.95, P < 0.05). These results indicate that the invasive strains regulate the production of virulence factors and, in turn, induce chronic dose‐related cytotoxicity.
The differential regulation of nitric oxide by Herpes simplex virus‐1 and ‐2 in a corneal epithelial cell line
Authors: Thakur Archana , Athmanathan Sreedharan , Willcox Mark
Published: March 2003

Herpes simplex keratitis is a significant cause of blindness worldwide. Nitric oxide (NO) has been shown to play a role in non‐specific defence mechanisms and cell signalling in bacterial and parasitic infections. We investigated if Herpes simplex virus (HSV) isolated from keratitis could induce NO production. Human corneal epithelial cells were infected with high (multiplicity of infection; MOI 0.4) and low (MOI 0.04) HSV‐1 and HSV‐2 concentrations. Culture supernatants were collected at 1 h, 4 h, 8 h, 12 h and 24 h post‐challenge. Samples were prepared by removal of proteins by ultrafiltration. Production of NO was measured using nitrite and nitrate assays. Herpes simplex virus‐1 downregulated the production of NO, while HSV‐2 upregulated NO production. Downregulation of NO could be a survival strategy against the cytotoxic action of NO, to eliminate infected cells. Upregulation of NO production may be associated with the presence of glycoproteins on the viral coat, which have been shown to induce NO in other disease conditions. Further studies are required to confirm the role of NO in viral keratitis.
Susac syndrome: Microangiopathy of the retina, cochlea and brain
Authors: Saw Valerie PJ , Canty Paul A , Green Catherine M , Briggs Robert J , Cremer Phillip D , Harrisberg Brian , McCluskey Peter , O’Day Justin , Paine Mark , Wakefield Denis , WatsonFracp John DG
Published: March 2003

Background: Susac syndrome is characterized by the triad of branch retinal arterial occlusions, encephalopathy and cochlear microangiopathy. The underlying process is believed to be a small vessel vasculitis causing microinfarcts in the retina, brain and cochlea.

Methods: Analysis of two male and two female cases of Susac syndrome recognized in Australia.

Results: In this series the epidemiology, mode of presentation, ophthalmologic features, neurologic and cochleovestibular features, radiologic characteristics, cerebrospinal fluid findings, therapeutic interventions, clinical course and outcome of Susac syndrome is examined. Key ophthalmologic differential diagnoses include systemic lupus erythematosis (SLE), Behçet’s syndrome and other vasculitides such as sarcoidosis, tuberculosis, syphilis and lymphoma. Neuro‐otologic features are most frequently misdiagnosed as multiple sclerosis.

Conclusion: Susac syndrome, first described in 1979, is becoming an increasingly recognized condition. Early recognition of the syndrome is important because treatment with systemic immunosuppression may minimize permanent cognitive, audiologic and visual sequelae.
Effects of triamcinolone acetonide on microglial morphology and quantitative expression of MHC‐II in exudative age‐related macular degeneration
Authors: Penfold Philip L , Wong James G , Gyory Joseph , Billson Francis A
Published: March 2003

Animal models, in vitro assays and pilot clinical studies suggest that intravitreal triamcinolone acetonide may be useful in the treatment of age‐related macular degeneration. The present case study reports the effect of intravitreal triamcinolone acetonide injection on a subretinal neovascular lesion, microglial morphology and quantitative expression of MHC‐II antigens. Triamcinolone acetonide significantly decreased MHC‐II expression consistent with immunocytochemical observations which revealed condensed microglial morphology. The modulation of subretinal oedema and microglial morphology correlates with in vitro observations suggesting that downregulation of inflammatory markers and endothelial cell permeability are significant features of the mode of action of triamcinolone acetonide.
Impaired vision and other factors associated with driving cessation in the elderly: the Blue Mountains Eye Study
Authors: Gilhotra Jagjit Singh , Mitchell Paul , Ivers Rebecca , Cumming Robert G
Published: March 2003

The aim of present study was to review vision and other factors associated with the cessation of driving. As part of the Blue Mountains Eye Study, detailed demographic information, driving status and medical history were taken. Visual acuity was measured during a standardized refraction and visual fields documented. Potential risk factors were decided a priori. Among the 3654 Eye Study participants, 2831 (77.5%) had driven a motor vehicle in the past, of whom 2379 (84.0%) were current drivers and 452 (16.0%, 95% CI 14.6–17.4%) said they had stopped driving. Older persons and women were more likely to have stopped driving. After adjusting for age and sex, sensory impairment affecting vision and hearing, plus chronic medical conditions and benzodiazepine use were significantly associated with cessation of driving. The study found that sensory impairment, particularly visual parameters, was associated with the decision to stop driving by older subjects.
Effects of varying 5‐fluorouracil exposure duration on Tenon’s capsule fibroblasts
Authors: Merriman Michael B , Mora Justin S , Beaumont Brent W , Merrilees Mervyn J
Published: March 2003

Purpose: 5‐Fluorouracil (5‐FU) is used intraoperatively to improve the success of trabeculectomy. Common practice is a 5‐min application of 5‐FU delivered via a Weck Cel sponge. The aim of this study was to determine if shorter exposure times were as effective in inhibiting Tenon’s capsule fibroblast proliferation.

Methods: Samples of Tenon’s capsules, obtained from young patients undergoing strabismus surgery, were immersed in vitro in 5‐FU (50 mg/mL) for periods ranging from 1 to 10 min. Control samples were exposed either to growth medium (M199) or 5‐FU vehicle alone. Explants were cultured for up to 7 days and analysed for cell density, cell viability using fluoroprobe detection, and cell proliferation determined by proliferating cell nuclear antigen (PCNA)‐staining.

Results: Exposure to 5‐FU for 1 and 5 min resulted in a similar and significant inhibition of the culture‐induced increase in stromal cell density (P < 0.01), a significant reduction in the percentage of viable cells (P < 0.02), and reduced PCNA indices, compared with controls. Exposure times of 3 and 10 min produced similar results.

Conclusions: In vitro, under conditions of organ culture, a 1‐min exposure to 5‐FU had a significant antiproliferative effect on fibroblasts of Tenon’s capsule, and was similar to 5 min of exposure. Optimal intraoperative 5‐FU exposure time may be as little as 1 minute.
Separation of contour and area dependent components in the first and second order kernels of the multifocal pattern appearance evoked potential
Authors: Crewther David P , Luu Chi D , Crewther Sheila G
Published: March 2003

The non‐linearities of the diffuse flash visual evoked potential (VEP) have been shown to generate separable waves corresponding to Magnocellular and Parvocellular contributions. The authors wished to investigate whether, under conditions of isoluminance, the chromatic pattern appearance VEP shows waveforms that are related to both the processing of contours (the pattern) and the processing of the diffuse stimulation (from the area lying between the contours). The VERIS multifocal system was used to record monocular VEP. Standard 2‐ring, 3‐ring, 5‐ring and 7‐ring VERIS pattern stimuli were employed with a cardboard circular aperture used to blank the stimulus monitor to a 9‐cm diameter field. The results for four subjects were recorded. The first order kernel responses showed a significant increase in amplitude with total contour length. In comparison, the amplitudes of the first and second slices of the second order kernel did not increase with contour length. It appears that the contour‐dependent component has negligible non‐linear components. It is proposed that the constant, non‐zero responses of the higher order kernel components reflects contributions from the diffuse chromatic VEP.
Eye care for the community
Authors: Taylor Hugh R
Published: March 2003

Eye disease is a huge and largely unrecognized problem in our community, especially in the elderly. The Visual Impairment Project, an intensive epidemiological study conducted by the Centre for Eye Research Australia (CERA) from 1991 to 1999, determined the prevalence, causes and risk factors for eye disease in Australia, and helped identify a series of specific, often simple, steps and strategies to significantly reduce its impact. A distillation of CERA"s findings has highlighted the growing problem of eye disease in our com­munity. In addition, CERA has joined with other interested bodies to form Vision 2020: the Right to Sight Australia. This partnership was established in response to the Global Initiative to Eliminate Avoidable Blindness by the year 2020 − Vision 2020: the Right to Sight. This Global Initiative was established by the World Health Organization and the International Agency for the Prevention of Blindness. Vision 2020 Australia aims to be the peak body for all those involved in vision care in its broadest sense in Australia, and to put vision on the national agenda.
Analysis of risk factors that may be associated with progression from ocular hypertension to primary open angle glaucoma
Authors: Landers John , Goldberg Ivan , Graham Stuart L
Published: March 2003

Background: As a multifactorial disease, glaucoma may be associated with pressure‐dependent and pressure‐independent factors. Ocular hypertension (OHT) may develop into primary open angle glaucoma (POAG) for many patients. Groups with OHT and POAG were compared for pressure‐dependent and independent risk factors. A high prevalence of any factor(s) could indicate a contribution to progression from OHT to POAG.

Methods: A sample of patients with POAG (n = 438) and with OHT (n = 301) were selected from those attending a tertiary referral private glaucoma practice, and data were collected regarding age and intraocular pressure at the time of diagnosis, sex, family history of glaucoma, systemic hypertension, diabetes, Raynaud's phenomenon, migraine and myopia.

Results: After multivariate analysis, older age at time of diagnosis (χ25 = 73.89, P < 0.001), myopia (odds ratio [OR] = 1.5, 95% confidence interval [CI] 1.0−2.2; P < 0.05), a family history of glaucoma (OR = 1.6, 95% CI 1.1−2.3; P < 0.01) and a high intraocular pressure (χ24 = 16.96; P = 0.002) were found to be more prevalent among those with POAG. No other significant differences could be found between the two groups.

Conclusion: Patients who have OHT may be at higher risk of developing POAG if they also have myopia, a family history of glaucoma or are of older age.
Effectiveness of local anaesthesia for external dacryocystorhinostomy
Authors: McNab Alan A , Simmie Richard J
Published: March 2003

Purpose: To establish the effectiveness, complications and patient acceptance of local anaesthesia (LA) with intra‐venous sedation, for external dacryocystorhinostomy (DCR).

Methods: Data were prospectively collected over a 4‐year period (1997−2000) on all patients undergoing external DCR under LA with intravenous sedation by one surgeon and one anaesthetist, using a standardized technique.

Results: Of 183 DCR procedures, 145 (76.5%) were performed using LA in 123 patients aged 24−84 years (median 64 years). Eleven simultaneous bilateral DCR procedures were performed under LA. Another 11 patients had a contralateral DCR at a later date. In only three DCR (2.1%) was supplementation of LA required during the procedure because of pain. The only complication of the technique was one retrobulbar haemorrhage from the medial peribulbar injection. In this patient, the procedure was completed satisfactorily without further sequelae. All patients found the technique acceptable and all 11 patients who returned for surgery on the opposite side at a later date elected to have surgery under LA again.

Conclusions: External DCR can be satisfactorily and safely performed under LA with a high level of patient acceptance.
Retinal manifestations of ophthalmic artery hypoperfusion
Authors: Ong Terrence J , Paine Mark , O'Day Justin
Published: March 2003

Ophthalmic artery hypoperfusion is a relatively uncommon clinical entity. This study illustrates the posterior segment findings of ophthalmic artery hypoperfusion in a series of nine patients. Colour photographs and relevant fluorescein angiograms highlighting the findings are shown. The retinal manifestations of ophthalmic artery hypoperfusion in this series of patients include midperipheral haemorrhages, dilated retinal veins, optic disk collaterals, optic disk neo­vascularization, cotton wool spots, grey intraretinal lesions, fundus pallor, optic disk swelling and choroidal infarcts. Recognition of the ophthalmic changes in this condition may lead to detection of carotid artery disease, the surgical and medical treatment of which has important bearing on patient management.
The corneal thickness and intraocular pressure story: where are we now?
Authors: Lee Graham A , Khaw Peng T , Ficker Linda A , Shah Peter
Published: March 2003

A review of the current literature was conducted regarding the effect of corneal thickness on the diagnosis of glaucoma, and the influence of excimer laser refractive surgery on intraocular pressure (IOP) measurement with Goldmann applanation tonometry. In general, normals and primary open angle glaucoma patients have a similar distribution of corneal thickness; however, there is a wide variation, ranging from 427 to 716 µm. Normal tension glaucoma patients have a tendency towards thinner corneas than normals; however, there is an overlap of thickness measurements of more than two‐thirds in 95% of patients. There is a trend for ocular hypertensives to have thicker corneas than normals, but again there is an overlap of about one‐third in 95% of patients. The general trend after excimer laser refractive surgery is for a decrease in IOP, with a mean fall in IOP measured of 0.63 mmHg per dioptre correction. There is, however, a large scatter of values with some patients having the same or lower IOP post‐laser, but with other patients measuring higher pressures. Corneal thickness can influence IOP measurement by Goldmann applanation tonometry; however, the magnitude of the effect is subject to much individual variation.