bluuebunny/crossref_metadata_2025 huggingface dataset:
Hereditary cerebral hemorrhage with amyloidosis‐Dutch type
Authors: Maat‐Schieman Marion , Roos Raymund , Van Duinen Sjoerd
Published: December 2005

The amyloid β‐protein (Aβ) E22Q mutation of the rare disorder hereditary cerebral hemorrhage with amyloidosis‐Dutch type (HCHWA‐D) causes severe cerebral amyloid angiopathy (CAA) with hemorrhagic strokes of mid‐life onset and dementia. The mutation does not affect total Aβ production but may alter the Aβ1–42:Aβ1–40 ratio, and affect the proteolytic degradation of Aβ and its transport across the blood–brain barrier. Aβ E22Q aggregates faster into more stable amyloid‐like fibrils than wild‐type Aβ. Non‐fibrillar Aβ(x‐42) deposits precede the appearance of fibrils and the deposition of Aβ(x‐40) in the vascular basement membrane. CAA severity tends to increase with age but may vary greatly among patients of comparable ages. Lumenal narrowing of affected blood vessels, leukoencephalopathy, CAA‐associated vasculopathies, and perivascular astrocytosis, microgliosis, and neuritic degeneration complicate the development of HCHWA‐D CAA. Parenchymal Aβ deposition is also enhanced in the HCHWA‐D brain with non‐fibrillar membrane‐bound Aβ(x‐42) deposits evolving into relatively fibrillar diffuse plaques variously associated with reactive astrocytes, activated microglia, and degenerating neurites. Plaque density tends  to  decrease  with  age.  Neurofibrillary  degeneration is absent or limited. HCHWA‐D dementia is associated with CAA severity independently of Braak stage, age, and plaque density. Particularly, microaneurysms may contribute to the development of (small) hemorrhages/infarcts and the latter to cognitive decline in affected subjects. However, the relative importance of cerebral hemorrhages/infarcts, white matter damage and/or other CAA‐ or Aβ‐related factors for cognitive deterioration in HCHWA‐D remains to be determined.
Is motoneuronal cell death in amyotrophic lateral sclerosis apoptosis?
Authors: Yamazaki Mineo , Esumi Eisaku , Nakano Imaharu
Published: December 2005

To clarify the controversy concerning whether the cell death of motor neurons in ALS is apoptosis, we investigated the expression of Apaf‐1 and caspase‐9 mRNA in spinal cord tissue obained at autopsy from patients with ALS and controls using RT‐PCR; the presence of in situ nuclear DNA fragmentation in motor neurons by the TdT‐mediated dUTP‐biotin nick end‐labeling (TUNEL) method; and immunocytochemical localization of Apaf‐1 and caspase‐3, which are known as promotors of apoptotic processes. Although Apaf‐1 and caspase‐9 mRNAs levels were increased in ALS, Apaf‐1 immunoreactivity (IR) showed no significant difference between ALS and the control, and caspase‐3 IR was not observed in ALS motoneurons, casting doubt on the notion that motor neurons in ALS undergo death by the classic apoptotic pathway. Although TUNEL‐positive motor neurons were frequently observed in the anterior horn in ALS, these neurons always showed an atrophic cell body with a shrunken and pyknotic nucleus, indicating that they were at the terminal stage of degeneration. No apoptotic bodies were seen. These findings suggest that the mechanism of motor neuronal cell death in ALS might not be apoptosis, but some other as yet unidentified mechanism.
Review of complex breast cysts: implications for cancer detection and clinical practice
Authors: Houssami Nehmat , Irwig Les , Ung Owen
Published: December 2005

The use of ultrasound in breast diagnosis has resulted in the increasing identification of incidental benign‐appearing lesions, of which complex (or atypical) breast cysts are frequently reported. Complex breast cysts were estimated to be reported in approximately 5% of breast ultrasound examinations. A systematic review of the literature on sonographically detected complex breast cysts was carried out. The quality of primary studies and extracted data on cancer detection was assessed. Very few studies have examined complex breast cysts and quantified the associated cancer detection rate. In most of these studies, subjects have been selected on the basis of progress to intervention, which would overestimate the likelihood of malignancy. The only study to examine complex cysts from all consecutive ultrasounds reported one case of non‐invasive cancer from 308 lesions − 0.3% (95% confidence interval, 0.01−1.84). Ultrasound features associated with a higher risk of the lesion being a cancer are: thickened walls, thick internal septations, a mix of cystic and solid components, and an imaging classification of indeterminate. Using the information from the present review, complex breast cysts were categorized on the basis of associated risk of malignancy, and an approach to the management of these lesions to assist clinical decision‐making was suggested. Provided adequate information is given to the patient, complex breast cysts with a very low risk of malignancy do not always require image‐guided biopsy.
Correlation between macroscopic changes of arthrosis and the posterior cruciate ligament histology in the osteoarthritic knee
Authors: Stubbs Geoffrey , Dahlstrom Jane , Papantoniou Peter , Cherian Maya
Published: December 2005

Background:  There is ongoing debate about the role of the posterior cruciate ligament (PCL) in total knee arthroplasty. Advocates of PCL retention cite better soft tissue balance and improved proprioception, whereas opponents report late flexion instability. The results of knee replacement are similar whether the PCL is retained or sacrificed. The aim of the present study was to examine the PCL for histological changes that would infer its competence and correlate these with changes easily observed by the operating surgeon.

Methods:  A prospective study of 50 osteoarthritic knees was performed.

Results:  Histology of the PCL showed changes secondary to degeneration and trauma. In most of the ligaments examined, arteriosclerosis and fibrosis were present. Half of the PCL examined showed perineural fibrosis, myxoid change and hyalinization. These changes, although very frequent, did not correlate well to the changes observed in either the anterior or PCL, or in the overall severity of osteoarthrosis.

Conclusions:  Posterior cruciate ligaments usually show degenerative and chronic traumatic change of varying degrees on histology. The changes are not predictable from inspection of the knee at surgery. The frequency of these changes suggests that many osteoarthritic PCL are of indifferent quality and the surgeon should consider this when choosing the style of knee replacement.
A survey of the current surgical treatment of gallstones in Queensland
Authors: Askew James
Published: December 2005

Background:  To survey the current practice of general surgeons in Queensland in their management of patients with gallstones.

Methods:  A postal survey of 123 surgeons practising in Queensland.

Results:  There were 114 responses to the questionnaire (92.7%) and seven were excluded from the analysis. Laparoscopic cholecystectomy (LC) was preferred by 97.2% and operative cholangiography was almost always attempted by 82.3%. One‐third of surgeons used drains routinely. In cases of acute cholecystitis, 56 surgeons (52.3%) favoured laparoscopic cholecystectomy on the same admission. Operative cholangiography (OC) was almost always attempted by 64.8% of surgeons during acute laparoscopic cholecystectomy. Only 3.8% of surgeons frequently offered day case surgery and 51% never offered it.

Conclusions:  Laparoscopic cholecystectomy is the treatment of choice of nearly all Queensland surgeons in the elective and acute situations. Routine operative cholangiography is favoured by the majority of surgeons. Day case surgery is presently offered by a minority of surgeons.
The hospital costs of treating necrotizing fasciitis
Authors: Widjaja Audi B. , Tran Anh , Cleland Heather , Leung Michael , Millar Ian
Published: December 2005

Background:  Management of necrotizing fasciitis places significant demands upon hospital and medical resources. A successful management usually requires extensive surgical intervention and an adjunct hyperbaric oxygen treatment. The cost impact on the health care system has not been well characterized. We have, therefore, analysed the cost of treating this disease at an Australian tertiary referral hospital with extensive case experience and well‐developed financial costing systems and have compared this with the current casemix‐based government funding arrangements applying in Victoria, Australia.

Methods:  Data was extracted from the medical records of 92 sequential patients treated by the Alfred Hospital (Melbourne, Australia) during the four financial years 2000−04. Clinical costing data and government funding data was provided by the hospital's Finance Departments.

Results:  The total Alfred Hospital in‐patient costs for treating the patients was $5 935 545 with a mean cost per patient of $64 517 (range, $1025 to $514 889). The total casemix‐based funding allocation derived from treating these patients was calculated at $3 208 664 with the per patient mean $34 887 (range, $1331 to $387 168). This analysis does not include allowance for non‐Alfred Hospital costs such as those incurred by the ambulance service, referring hospitals, for rehabilitation or as a result of the burden of residual disability.

Conclusions:  This study has confirmed that a significant economic burden is involved in treating necrotizing fasciitis. There is a substantial difference between the hospital costs and government funding for treating these patients in the Australian setting.
Cystic adventitial disease: a case report and literature review
Authors: Vasudevan Arvind , Halak Moshe , Lee Steven , Ong Solomon , Nadkarni Sanjay
Published: December 2005

Cystic adventitial disease (CAD) is a rare non‐atherosclerotic cause of peripheral vascular disease (PVD). We describe a 54‐year‐old man who presented with calf claudication and catheter angiography showed the typical scallop appearances of CAD. Surgery involved resection of the diseased segment with a femoral popliteal venous bypass graft. A literature review revealed the different theories for pathogenesis, the investigation of choice being catheter angiography and the treatment excision with bypass grafting.
Agronomic practises for weed control in turmeric (Curcuma longa L.)
Authors: HOSSAIN MOHAMMAD AMZAD
Published: December 2005

Weeds are the main problem with turmeric (Curcuma longa L.) cultivation where herbicides are not allowed. This is because herbicides cause water contamination, air pollution, soil microorganism hazards, health hazards, and food risks. Considering turmeric's medicinal value and the environmental problems caused by herbicides, various agronomic practises have been evaluated for non‐chemical weed control in turmeric. One additional weeding is required before turmeric emergence and weed infestation is much higher when turmeric is planted in February and March, as compared to April, May or June planting. A similarly higher yield of turmeric is achieved when it is planted in February, March, and April, compared to late plantings. Weed emergence and interference are not affected by planting depth, seed size, planting pattern, planting space, ridge spacing, and the row number of turmeric until 60 days after planting. This is because turmeric cannot develop a canopy structure until then. Thereafter, weed infestation reduces similarly and significantly when turmeric is planted at depths of 8, 12, and 16 cm, compared to shallower depths. The yield of turmeric at these depths is statistically the same, but the yield for the 16 cm depth is difficult to harvest and it tends to decrease. Turmeric grown from seed rhizomes (daughter rhizomes) weighing 30–40 g reduces weed infestation significantly and obtains a significantly higher yield compared to smaller seeds. The mother rhizome also can suppress weed infestation and increase the yield markedly. Around 9% weed control and 11% higher yield are achieved by planting turmeric in a triangular pattern compared to a quadrate pattern. The lowest weed infestation is found in turmeric grown in a 20 or 30 cm triangular pattern and the highest yield is obtained with the 30 cm triangular pattern. Turmeric gown on two‐row ridges spaced 75 cm apart shows excellent weed control efficiency and obtains the highest yield. This review concludes that turmeric seed rhizomes of 30–40 g and/or the mother rhizome could be planted in a 30 cm triangular pattern at the depth of 8–12 cm on two‐row ridges spaced 75–100 cm apart during March to April in order to reduce weed interference and obtain a higher yield. Mulching also suppresses weed growth and improves the yield. The above agronomic practises could not control weeds completely; biological weed management practises could be integrated in turmeric fields using rabbits, goats, sheep, ducks, cover crops or intercrops.
Plant growth inhibitors: Patchoulane‐type sesquiterpenes from Cyperus rotundus L.
Authors: MORIMOTO MASANORI , KOMAI KOICHIRO
Published: December 2005

Two sesquiterpene ketones, cyperotundone and α‐cyperone, were isolated from dried tubers of purple nutsedge (Cyperus rotundus L.) as major constituents: ≈0.26% and 0.1% of dried tuber, respectively. These allelochemicals affect plant growth, but we consider that these terpenoids undergo modification when they are released into the rhizosphere from the donor plant. For the structure–activity relationship study, cyperotundone was oxidized with selenium dioxide in acetic acid to 4‐patchoulene‐2,3‐dione and 4‐patchoulene‐2,3,6‐trione. Subsequent hydrogenation of 4‐patchoulene‐2,3‐dione and 4‐patchoulene‐2,3,6‐trione gave hydroxylated derivatives, cyperotundon‐2‐ol and 3‐hydroxy‐4‐patchoulene‐2,6‐dione, respectively. 4‐Patchoulene‐2,3‐dione inhibited the hypocotyl growth of lettuce seedlings but promoted radicle elongation at 0.1−2 mg L−1 concentration without chlorosis. Moreover, this radicle elongation recovered with the addition of galactose and was not antagonized by gibberellin A3. The effect of 4‐patchoulene‐2,3,6‐trione showed a similar chlorosis, caused by 3,6,9‐sugetriol triketone, against lettuce seedlings. These ketones did not show the radicle elongation.
Quality of life after total mesorectal excision for rectal cancer
Authors: Gosselink M. P. , Busschbach J. J. , Dijkhuis C. M. , Stassen L. P. , Hop W. C. , Schouten W. R.
Published: December 2005

Background  After total mesorectal excision for rectal cancer, many surgeons try to avoid an abdominoperineal resection (APR) by performing a transanally double stapled low colo‐rectal anastomosis (LRA), frequently without a pouch. This policy is mainly based on the assumption that the quality of life after such LRA is higher than after APR. It has been suggested that a better functional outcome and therefore a higher quality of life might be achieved by a colo‐anal J‐pouch anastomosis (CPA). The aim of this study was to assess quality of life among disease‐free survivors after APR, LRA and CPA.

Methods  The charts of 301 consecutive patients who had undergone surgery for cancer in the middle or lower third of the rectum were analysed. Two hundred four patients were eligible for inclusion. The quality of life among these patients was assessed using one generic (EQ‐5D) and two disease‐specific questionnaires (EORTC QLQ‐C30 and EORTC QLQ‐CR38).

Results  The response rate was 82%. The median follow‐up was 31 months. Overall, quality of life was good but CPA patients had better quality of life scores than APR and LRA patients. This difference was not only due to the better functional outcome but also to the lower incidence of disturbed micturition and sexual problems in the CPA group.

Conclusion  The quality of life after colo‐anal J‐pouch anastomosis is better than after abdominoperineal resection (APR) and low colo‐rectal anastomosis (LRA). The quality of life after APR is similar to that after LRA.
Is pre‐operative radiotherapy necessary in T1‐T3 rectal cancer with TME?
Authors: MacKay G. , Downey M. , Molloy R. G. , O'Dwyer P. J.
Published: December 2005

Objective  The indications for pre‐operative radiotherapy in rectal cancer are still unclear with the exception of T4 tumours. The aim of this study was to assess local and overall recurrence in patients with T1‐T3 rectal cancers undergoing total mesorectal excision (TME).

Methods  Prospective data was collected from 150 patients with rectal cancer treated in one surgical centre between July 1997 and July 2002. One hundred and twenty‐nine primary resections were carried of which 102 were with curative intent. Seventy‐nine patients with T1‐T3 tumours were included in the analysis. Nine had local resections and 70 underwent TME; 19 of the 70 patients were node positive and 51 were node negative.

Results  At a median follow‐up of 37 months (range 19–79 months) there were 3 (4.3%) isolated local recurrences. One node positive patient developed isolated local recurrence compared with 2 node negative patients. The node positive patient died from a myocardial infarction while the two node negative patients died as a consequence of local recurrence. Three (4.3%) of 70 patients developed systemic relapse all of whom were node positive. The cancer specific mortality rate over the same follow‐up period was 3/19 for node positive patients and 2/51 for node negative patients. Of 9 patients who had local resections, none developed local recurrence or systemic relapse.

Conclusions  With TME the rate of local recurrence in T1‐T3 tumours is low. Our results do not support the use of pre‐operative radiotherapy for these patients.
Prospective randomised study of urgent haemorrhoidectomy compared with non‐operative treatment in the management of prolapsed thrombosed internal haemorrhoids
Authors: Allan A. , Samad A. J. , Mellon A. , Marshall T.
Published: December 2005

Objective  To compare the outcome of urgent haemorrhoidectomy with conservative treatment for prolapsed thrombosed internal haemorrhoids.

Methods  A prospective randomised study of 50 patients with prolapsed thrombosed internal haemorrhoids was carried out using clinical and ultrasonic outcome measures. Peri‐operative bed occupancy and the presence of symptoms at 6 and 24 months were compared. Endoanal ultrasonic scanning was carried out to investigate anal sphincter integrity in those patients willing to be studied.

Results  The median length of hospital stay for the group treated conservatively; 2 nights (range 1–9 nights) was significantly shorter than for the group treated by urgent haemorrhoidectomy; 4 nights (range 1–12 nights, P < 0.01). There was no difference between treatment groups in the number of patients with symptoms at six or 24 months. Urgent haemorrhoidectomy was associated with a significantly higher incidence of endosonographically detected anal sphincter damage in 18 patients: 66%vs 0% (P = 0.009).

Conclusion  Conservative treatment for prolapsed thrombosed internal haemorrhoids is associated with shorter in patient stay and less anal sphincter damage compared with operative treatment.
Isolation and characterization of polymorphic microsatellite loci in the scarlet ibis (Eudocimus ruber— Threskiornithidae‐Aves)
Authors: SANTOS M. S. , GONÇALVES E. C. , BARBOSA M. S. R. , SILVA A. , SCHNEIDER M. P. C.
Published: December 2005

Here we presented 10 polymorphic microsatellite loci obtained from scarlet ibis through an enriched genomic library. The analysis of 45 individuals from three Brazilian natural populations showed allelic diversity ranged from three to 17 alleles, observed heterozygosity ranged from 0.03 to 0.92, and expected heterozygosity ranged from 0.06 to 0.92. These highly variable microsatellite loci can provide means for assessing overall genetic variation in its remnant natural populations, which may help the development of effective conservation programs.
Isolation and characterization of microsatellite markers from the panic moth, Saucrobotys futilalis L. (Lepidoptera: Pyralidae: Pyraustinae)
Authors: GRANT J. B. , BOGDANOWICZ S. M.
Published: December 2005

The panic moth is a widely distributed North American pyralid moth with gregarious, nest‐building larvae. Primers for 12 polymorphic microsatellite loci were developed to assay relatedness in nest groups and population structure in the eastern half of the moth's range. Primers were tested on 42 individuals (one from each of 42 nests) collected in the states of New York, Virginia and Georgia. All loci were polymorphic and exhibited varying degrees of allelic variation (4–24 alleles). These primers will enable further research into the social structure of these gregarious caterpillars.
Quality Improvement Implementation and Hospital Performance on Quality Indicators
Authors: Weiner Bryan J. , Alexander Jeffrey A. , Shortell Stephen M. , Baker Laurence C. , Becker Mark , Geppert Jeffrey J.
Published: December 2005

Objective. To examine the association between the scope of quality improvement (QI) implementation in hospitals and hospital performance on selected indicators of clinical quality.

Data Sources. Secondary data from 1997 mailed survey of hospital QI practices, Medicare Inpatient Database, American Hospital Association's Annual Survey of Hospitals, the Bureau of Health Professions' Area Resource File, and two proprietary data sets compiled by Solucient Inc. containing data on managed care penetration and hospital financial performance.

Study Design. Cross‐sectional study of 1,784 community hospitals to assess relationship between QI implementation approach and six hospital‐level quality indicators.

Data Collection/Abstraction Methods. Two‐stage instrumental variables estimation in which predicted values (instruments) of four QI scope variables and control (exogenous) variables used to estimate hospital‐level quality indicators.

Principal Findings. Involvement by multiple hospital units in QI effort is associated with worse values on hospital‐level quality indicators. Percentage of hospital staff and percentage of senior managers participating in formally organized QI teams are associated with better values on quality indicators. Percentage of physicians participating in QI teams is not associated with better values on the hospital‐level quality indicators studied.

Conclusions. Results supported the proposition that the scope of QI implementation in hospitals is significantly associated with hospital‐level quality indicators. However, the direction of the association varied across different measures of QI implementation scope.
Disparities in the Reporting and Treatment of Health Conditions in Children: An Analysis of the Medical Expenditure Panel Survey
Authors: Guevara James P. , Mandell David S. , Rostain Anthony L. , Zhao Huaqing , Hadley Trevor R.
Published: December 2005

Objectives.To determine whether racial and ethnic disparities in health care use differ for physical and behavioral health conditions.

Data Sources.Secondary analysis of the 1996–1997 Medical Expenditure Panel Survey.

Study Design.Retrospective cohort study of children aged 2–18 years old who were members of participating households. Children were categorized as Hispanic, black, or white. Differences in caregiver‐reported behavioral and physical health conditions and services use were compared, and estimates were weighted to reflect the complex sampling scheme.

Principal Findings.Of eligible children weighted to represent over 44 million in each year, 13–15 percent were Hispanic, 14 percent black, and 68–70 percent white. After adjusting for potential confounding, Hispanic and black children were less likely to report externalizing behavioral conditions than white children. Black but not Hispanic children were more likely than white children to report asthma. In addition, Hispanic and black children were less likely to report ambulatory visits, and black children were less likely to report receiving a prescription medication than white children. There were no differences in reported emergency room visits or hospitalizations. Interactions between race and various health conditions, health status, insurance, and income were not significant.

Conclusions.In this nationally representative sample, we identified racial and ethnic disparities in the reporting of health conditions and the use of discretionary health services. Disparities differed between those with behavioral conditions and those with physical conditions. These disparities were not explained by traditional measures including the presence of health conditions, health status, insurance, and family income, and suggest that national surveys such as Medical Expenditure Panel Survey may benefit from the inclusion of additional explanatory measures.
Variation in Hospital Length of Stay: Do Physicians Adapt Their Length of Stay Decisions to What Is Usual in the Hospital Where They Work?
Authors: de Jong Judith D. , Westert Gert P. , Lagoe Ronald , Groenewegen Peter P.
Published: December 2005

Objective. To test the hypothesis that physicians who work in different hospitals adapt their length of stay decisions to what is usual in the hospital under consideration.

Data Sources. Secondary data were used, originating from the Statewide Planning and Research Cooperative System (SPARCS). SPARCS is a major management tool for assisting hospitals, agencies, and health care organizations with decision making in relation to financial planning and monitoring of inpatient and ambulatory surgery services and costs in New York state.

Study Design. Data on length of stay for surgical interventions and medical conditions (a total of seven diagnosis‐related groups [DRGs]) were studied, to find out whether there is more variation between than within hospitals. Data (1999, 2000, and 2001) from all hospitals in New York state were used. The study examined physicians practicing in one hospital and physicians practicing in more than one hospital, to determine whether average length of stay differs according to the hospital of practice. Multilevel models were used to determine variation between and within hospitals. A t‐test was used to test whether length of stay for patients of each multihospital physician differed from the average length of stay in each of the two hospitals.

Principal Findings. There is significantly (p<.05) more variation between than within hospitals in most of the study populations. Physicians working in two hospitals had patient lengths of stay comparable with the usual practice in the hospital where the procedure was performed. The proportion of physicians working in one hospital did not have a consistent effect for all DRGs on the variation within hospitals.

Conclusion. Physicians adapt to their colleagues or to the managerial demands of the particular hospital in which they work. The hospital and broader work environment should be taken into account when developing effective interventions to reduce variation in medical practice.
Application of Regression‐Discontinuity Analysis in Pharmaceutical Health Services Research
Authors: Zuckerman Ilene H. , Lee Euni , Wutoh Anthony K. , Xue Zhenyi , Stuart Bruce
Published: December 2005

Objective. To demonstrate how a relatively underused design, regression‐discontinuity (RD), can provide robust estimates of intervention effects when stronger designs are impossible to implement.

Data Sources/Study Setting. Administrative claims from a Mid‐Atlantic state Medicaid program were used to evaluate the effectiveness of an educational drug utilization review intervention.

Study Design. Quasi‐experimental design.

Data Collection/Extraction Methods. A drug utilization review study was conducted to evaluate a letter intervention to physicians treating Medicaid children with potentially excessive use of short‐acting β2‐agonist inhalers (SAB). The outcome measure is change in seasonally‐adjusted SAB use 5 months pre‐ and postintervention. To determine if the intervention reduced monthly SAB utilization, results from an RD analysis are compared to findings from a pretest–posttest design using repeated‐measure ANOVA.

Principal Findings. Both analyses indicated that the intervention significantly reduced SAB use among the high users. Average monthly SAB use declined by 0.9 canisters per month (p<.001) according to the repeated‐measure ANOVA and by 0.2 canisters per month (p<.001) from RD analysis.

Conclusions. Regression‐discontinuity design is a useful quasi‐experimental methodology that has significant advantages in internal validity compared to other pre–post designs when assessing interventions in which subjects' assignment is based on cutoff scores for a critical variable.
Stabilization of Ethanol‐Based Alumina Suspensions
Authors: Menon Mohan , Decourcelle Sophie , Ramousse Severine , Larsen Peter Halvor
Published: December 2005

Al2O3 powders have been successfully dispersed in ethanol by varying the suspension acidity. An operational pH (O.pH) was defined to measure the acidity of these ethanol‐based suspensions. The isoelectric point of Al2O3 in ethanol was at an O.pH of 8. According to Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, suspensions between an O.pH of 3.5–10.5 possessed only attractive inter‐particle potential. Suspensions below 3.5 had high ζ potential, fine particle size, and were Newtonian. However, suspensions at high pH were shear thinning and consisted of agglomerates, despite their high ζ potential. The use of citric acid as a dispersant has also been investigated. At an O.pH of 3, optimum additions of citric acid between 0.6 and 1.0 wt% decreased the particle size, resulted in repulsive inter‐particle potentials and increased the solid loading capacity to 15 vol% from 2 vol% while maintaining Newtonian behavior and similar viscosity to suspensions at O.pH 2. Addition of citric acid created agglomerated suspensions that were negatively charged at O.pH 10.5 (obtained by adding NH4OH), but positively charged suspensions at O.pH 13.6 (obtained by adding tetramethylammonium hydroxide).
Erythrocyte complement receptor 1 (CR1) expression level is not associated with polymorphisms in the promoter or 3′ untranslated regions of the CR1 gene
Authors: Cockburn I. A. , Rowe J. A.
Published: December 2005

Complement receptor 1 (CR1) expression level on erythrocytes is genetically determined and is associated with high (H) and low (L) expression alleles identified by a HindIII restriction fragment‐length polymorphism (RFLP) in intron 27 of the CR1 gene. The L allele confers protection against severe malaria in Papua New Guinea, probably because erythrocytes with low CR1 expression, are less able to form pathogenic rosettes with Plasmodium falciparum‐infected erythrocytes. Despite the biological importance of erythrocyte CR1, the genetic mutation controlling CR1 expression level remains unknown. We investigated the possibility that mutations in the upstream or 3′ untranslated regions of the CR1 gene could control erythrocyte CR1 level. We identified several novel polymorphisms; however, the mutations did not segregate with erythrocyte CR1 expression level or the H and L alleles. Therefore, high and low erythrocyte CR1 levels cannot be explained by polymorphisms in transcriptional control elements in the upstream or 3′ untranslated regions of the CR1 gene.
A foliar disease model for use in wheat disease management decision support systems
Authors: Audsley E. , Milne A. , Paveley N.
Published: December 2005

A model of winter wheat foliar disease is described, parameterised and tested for Septoria tritici (leaf blotch), Puccinia striiformis (yellow rust), Erysiphe graminis (powdery mildew) and Puccinia triticina (brown rust). The model estimates disease‐induced green area loss, and can be coupled with a wheat canopy model, in order to estimate remaining light‐intercepting green tissue and hence the capacity for resource capture. The model differs from those reported by other workers in three respects. First, variables (such as weather, host resistance and inoculum pressure) that affect disease risk are integrated in their effect on disease progress. The agronomic and meteorological data called for are restricted to those commonly available to growers by their own observations and from meteorological service networks. Second, field observations during the growing season can be used both to correct current estimates of disease severity and to modify parameters that determine predicted severity. Third, pathogen growth and symptom expression are modelled to allow the effects of fungicides to be accounted for as protectant activity (reducing infections that occur postapplication) and eradicant activity (reducing growth of presymptomatic infections). The model was tested against data from a wide range of sites and varieties and was shown to predict the expected level of disease sufficiently accurately to support fungicide treatment decisions.
CLOTH‐BASED HYBRIDIZATION ARRAY SYSTEM FOR DETECTION OF TOXIN GENES ASSOCIATED WITH MAJOR FOODBORNE PATHOGENIC BACTERIA
Authors: GAUTHIER MARTINE , BLAIS BURTON W.
Published: December 2005

A simple cloth‐based hybridization array system (CHAS) was developed for the identification of toxin genes associated with major foodborne pathogenic bacteria, including toxigenic Escherichia coli, Vibrio cholerae and Salmonella spp. Bacterial isolates were subjected to a multiplex polymerase chain reaction incorporating digoxigenin (DIG)–deoxyuridine triphosphate and primers targeting a variety of toxin genes (verotoxin, Salmonella enterotoxin, cholera toxin and heat‐labile/stable enterotoxin), followed by hybridization of the amplicons with an array of probes immobilized on polyester cloth and subsequent immunoenzymatic assay of the bound DIG label. This system provided sensitive and specific detection of the different target toxin gene markers in a variety of bacterial isolates, exhibiting the expected patterns of reactivity with a panel of bacteria having defined toxigenicity profiles. The CHAS is a cost‐effective tool facilitating the determination of the potential toxigenic profile of bacteria in the food microbiology laboratory, thus contributing valuable information to the risk‐assessment process in the microbiological analysis of foods.
DETECTION OF ESCHERICHIA COLI O157:H7 THROUGH THE FORMATION OF SANDWICHED COMPLEXES WITH IMMUNOMAGNETIC AND FLUORESCENT BEADS†
Authors: TU SHU‐I , GOLDEN MARSHA , COOKE PETER , PAOLI GEORGE , GEHRING ANDREW
Published: December 2005

A new fluorescent sandwich method for the detection of Escherichia coli O157:H7 in ground beef was developed. Immunomagnetic beads (IMBs) precoated with anti‐E. coli O157:H7 antibody were used to capture and concentrate E. coli O157:H7 present in ground beef. Streptavidin‐coated fluorescent beads with anti‐E. coli O157:H7 to form immunofluorescent beads (IFBs) were used to detect the E. coli O157:H7 captured by the IMBs by forming IMBM–E. coli O157:H7N–IFBO sandwich complexes, where the subscripts M, N and O were variable but integral numbers. This sandwich technique was able to detect 500 cfu of the bacteria in a 0.5‐mL sample taken from a quantified and diluted broth culture. The method was then applied to detect E. coli O157:H7 in artificially contaminated ground beef. Known quantities of freshly cultured E. coli O157:H7 cells were added to 25‐g ground beef patties held in sterile bags with filters. The inoculated patties were stored at 7C overnight; 75 mL of E. coli broth was added to each sample, and the bags were incubated at 40C with shaking at 160 rpm for 4.5 h. After the enrichment, E. coli O157:H7 in the filtrate was captured and concentrated with IMBs and further conjugated with IFBs for detection. The results demonstrate that, after a 4.5‐h enrichment period, the developed procedure can detect the presence of E. coli O157:H7 in ground beef previously spiked with 1 cfu/g.
Cholesterol and synaptic transmitter release at crayfish neuromuscular junctions
Authors: Zamir Orit , Charlton Milton P.
Published: December 2005

During exocytosis of synaptic transmitters, the fusion of highly curved synaptic vesicle membranes with the relatively planar cell membrane requires the coordinated action of several proteins. The role of membrane lipids in the regulation of transmitter release is less well understood. Since it helps to control membrane fluidity, alteration of cholesterol content may alter the fusibility of membranes as well as the function of membrane proteins. We assayed the importance of cholesterol in transmitter release at crayfish neuromuscular junctions where action potentials can be measured in the preterminal axon. Methyl‐β‐cyclodextrin (MβCD) depleted axons of cholesterol, as shown by reduced filipin labelling, and cholesterol was replenished by cholesterol–MβCD complex (Ch‐MβCD). MβCD blocked evoked synaptic transmission. The lack of postsynaptic effects of MβCD on the time course and amplitude of spontaneous postsynaptic potentials or on muscle resting potential allowed us to focus on presynaptic mechanisms. Intracellular presynaptic axon recordings and focal extracellular recordings at individual boutons showed that failure of transmitter release was correlated with presynaptic hyperpolarization and failure of action potential propagation. All of these effects were reversed when cholesterol was replenished with Ch‐MβCD. However, focal depolarization of presynaptic boutons and administration of a Ca2+ ionophore both triggered transmitter release after cholesterol depletion. Therefore, both presynaptic Ca2+ channels and Ca2+‐dependent exocytosis functioned after cholesterol depletion. The frequency of spontaneous quantal transmitter release was increased by MβCD but recovered when cholesterol was reintroduced. The increase in spontaneous release was not through a calcium‐dependent mechanism because it persisted with intense intracellular calcium chelation. In conclusion, cholesterol levels in the presynaptic membrane modulate several key properties of synaptic transmitter release.
A low maternal protein diet during pregnancy and lactation has sex‐ and window of exposure‐specific effects on offspring growth and food intake, glucose metabolism and serum leptin in the rat
Authors: Zambrano E. , Bautista C. J. , Deás M. , Martínez‐Samayoa P. M. , González‐Zamorano M. , Ledesma H. , Morales J. , Larrea F. , Nathanielsz P. W.
Published: December 2005

Extensive epidemiological and experimental evidence indicates that a sub‐optimal environment during fetal and neonatal development in both humans and animals may programme offspring susceptibility to later development of chronic diseases including obesity and diabetes that are the result of altered carbohydrate metabolism. We determined the effects of protein restriction during pregnancy and/or lactation on growth, serum leptin, and glucose and insulin responses to a glucose tolerance test in male and female offspring at 110 days postnatal life. We fed Wistar rats a normal control 20% casein diet (C) or a restricted diet (R) of 10% casein during pregnancy. Female but not male R pups weighed less than C at birth. After delivery, mothers received the C or R diet during lactation to provide four offspring groups: CC (first letter maternal pregnancy diet and second maternal lactation diet), RR, CR and RC. All offspring were fed ad libitum with C diet after weaning. Relative food intake correlated inversely with weight. Offspring serum leptin correlated with body weight and relative, but not absolute, food intake in both male and female pups. Serum leptin was reduced in RR female pups compared with CC and increased in RC males compared with CC at 110 days of age. Offspring underwent a glucose tolerance test (GTT) at 110 days postnatal life. Female RR and CR offspring showed a lower insulin to glucose ratio than CC. At 110 days of age male RR and CR also showed some evidence of increased insulin sensitivity. Male but not female RC offspring showed evidence of insulin resistance compared with CC. Cholesterol was similar and triglycerides (TG) higher in male compared with female CC. Cholesterol and TG were higher in males than females in RR, CR and RC (P < 0.05). Cholesterol and TG did not differ between groups in females. Cholesterol and TG were elevated in RC compared with CC males. Nutrient restriction in lactation increased relative whole protein and decreased whole lipid in both males and females. RC females showed decreased relative levels of protein and increased fat. We conclude that maternal protein restriction during either pregnancy and/or lactation alters postnatal growth, appetitive behaviour, leptin physiology, TG and cholesterol concentrations and modifies glucose metabolism and insulin resistance in a sex‐ and time window of exposure‐specific manner.
The activity‐induced reduction of myofibrillar Ca2+ sensitivity in mouse skeletal muscle is reversed by dithiothreitol
Authors: Moopanar Terence R. , Allen David G.
Published: December 2005

The aim of this study was to further characterize the reduction of myofibrillar Ca2+ sensitivity in mouse muscle which has been observed after fatigue at 37°C. Muscle bundles and single fibres were isolated from mouse flexor digitorum brevis muscle and studied at 37°C. The single fibres were injected with the Ca2+ indicator indo‐1. Muscle fatigue was produced by 0.4 s tetani repeated at 4 s intervals until force had fallen to less than 50% of initial. Excitation–contraction coupling was assessed by measuring the cytosolic calcium concentration ([Ca2+]i) during tetani, and the maximum Ca2+‐activated force and the myofibrillar Ca2+ sensitivity were estimated from a series of tetani at different stimulation frequencies. Two main results were found. (i) The reduction of Ca2+ sensitivity only occurred when the muscle was intensely stimulated leading to fatigue. When the muscle was rested for 10 min at 37°C there was no significant change in Ca2+ sensitivity. (ii) If the membrane‐permeant thiol‐specific reducing agent dithiothreitol (0.5 mm) was applied to the muscle for 2 min following the fatigue protocol, the reduction in Ca2+ sensitivity was reversed. Dithiothreitol had no effect on Ca2+ sensitivity in unfatigued preparations. There was no effect of fatigue or dithiothreitol on tetanic [Ca2+]i or on the maximum Ca2+‐activated force. These results suggest that intense activity of skeletal muscle at 37°C causes the production of reactive oxygen species which oxidize a target protein. We propose that critical sulphydryl groups on the target protein(s) are converted to disulphide bonds and this reaction reduces Ca2+ sensitivity.
Control of interneurone firing pattern by axonal autoreceptors in the juvenile rat cerebellum
Authors: Mejia‐Gervacio Sheyla , Marty Alain
Published: December 2005

Recent work has shown that certain neurones have axonal GABAA receptors, whose tonic activation modifies their firing properties and neurotransmitter release capability. In addition, results obtained in interneurones of the molecular layer of the cerebellum indicate that action potential‐released GABA binds back to the axon that released it, generating an autoreceptor current. In the present paper, we show that at physiological Cl−i concentration (15 mm) and at 34–36°C, the autoreceptor current generates a large amplitude (up to 21 mV) afterdepolarization that lasts for about 150 ms, and that occasionally leads to double firing. Furthermore we show that elimination of the afterdepolarization, by either blocking GABAA receptors, or eliminating the autoreceptor currents through prolonged whole‐cell recording, decreases burst firing. Ih (a hyperpolarization‐activated current) was previously found to be prominent in interneurone axons. We show that blocking Ih leads to an increase in the amplitude of the autoreceptor current as well as of the associated afterdepolarization, suggesting a shunting effect of Ih on autoreceptor‐mediated afterdepolarization. Conversely, blocking Ih accentuates burst firing. The effects of autoreceptor‐mediated afterdepolarization on firing are prominent during a period of development when interneurone synapses are stabilized and vanish by postnatal day 17 (PN 17), together with the expression of the autoreceptor current. Altogether, this work reveals a new role for autoreceptors in the regulation of cell excitability and firing pattern, which may contribute to the development and stabilization of the cerebellar network.
Three-dimensional passive acoustic tracking of sperm whales (Physeter macrocephalus) in ray-refracting environments
Authors: Thode Aaron
Published: December 2005

A wide-aperture towed passive acoustic array is used to obtain ranges and depths of acoustically active sperm whales in the Gulf of Mexico in June 2004, by extending a technique previously reported [Thode, J. Acoust. Soc. Am. 116, 245–253 (2004)] to explicitly account for ray-refraction effects arising from a depth-dependent sound speed profile. Under this expanded approach, three quantities are measured from an impulsive sound: the time difference between direct-path arrivals on a forward and rear subarray, the time difference between the direct and surface-reflected paths on the rear subarray, and the acoustic bearing measured on the rear subarray. These quantities, combined with independent measurements of hydrophone depths and cable inclination, are converted into range-depth position fixes by implementing an efficient numerical procedure that uses a ray-tracing code to account for ray-refraction effects caused by depth-dependent sound speed profiles. Analytic expressions that assume a constant waterborne sound speed are also derived. Foraging depths of various sperm whales over 10days in June, 2004 are estimated using the numerical technique.
Self-to-other ratios measured in an opera chorus in performance
Authors: Ternström Sten , Cabrera Densil , Davis Pamela
Published: December 2005

Four volunteer members of the chorus of Opera Australia, representing four different voice categories, wore binaural pairs of wireless microphones during a penultimate dress rehearsal on the Opera Theater stage of the Sydney Opera House. From the recordings, data were obtained on sound levels and on the self-to-other ratios (SORs). The sound levels were comparable to those found in loud music in chamber choir performance. The average SOR ranged from +10to+15dB. Compared to chamber choirs in other types of room, the SOR values were high. On a separate occasion, the stage support parameters ST1 (early reflections) and ST2 (late reflections) were measured over the whole stage area. ST1 was about −16dB, which is typical for opera stages, and −20dB for ST2, which is unusually low. It is concluded that the SOR in the opera chorus depends mostly on choir formation, which is highly variable, and that an opera chorus artist generally can hear his or her own voice very well, but little of the others and of the orchestra. This was confirmed by informal listening to the recordings.
A model for large amplitude oscillations of coated bubbles accounting for buckling and rupture
Authors: Marmottant Philippe , van der Meer Sander , Emmer Marcia , Versluis Michel , de Jong Nico , Hilgenfeldt Sascha , Lohse Detlef
Published: December 2005

We present a model applicable to ultrasound contrast agent bubbles that takes into account the physical properties of a lipid monolayer coating on a gas microbubble. Three parameters describe the properties of the shell: a buckling radius, the compressibility of the shell, and a break-up shell tension. The model presents an original non-linear behavior at large amplitude oscillations, termed compression-only, induced by the buckling of the lipid monolayer. This prediction is validated by experimental recordings with the high-speed camera Brandaris 128, operated at several millions of frames per second. The effect of aging, or the resultant of repeated acoustic pressure pulses on bubbles, is predicted by the model. It corrects a flaw in the shell elasticity term previously used in the dynamical equation for coated bubbles. The break-up is modeled by a critical shell tension above which gas is directly exposed to water.