Effects of feeding strategy and age on live animal performance, carcass characteristics, and economics of short-term feeding programs for culled beef cows

To evaluate production and economic effects of feeding management strategy and age on intensively managed culled beef cows, a study was conducted using 125 cows of British breeding blocked by age (Young = 3 and 4 yr olds; LowMid = 5 and 6 yr olds; HighMid = 7 and 8 yr olds; and Aged = 9 yr and older) and assigned to one of three steam-flaked corn based feeding strategies. Treatments were as follows: Conservative (CSV), 30% roughage throughout; Standard (STD), decrease roughage from 30 to 10% over 20 d; and Aggressive (AGR), decrease roughage from 30 to 10% over 10 d. There were four pens per treatment in a randomized complete block design. Cows were fed for a total of 54 d, and BW was measured on d 0, 14, 28, 42, and 54. Half the cows from each pen were randomly selected and slaughtered at a commercial abattoir, and carcass data were collected. Average daily gain, daily DMI, and G:F during each weigh period and across the entire feeding period were calculated. Over the 54-d feeding period, strategies that employed more energy-dense diets numerically increased ADG (1.28, 1.63, and 1.55 +/- 0.14 kg/d for CSV, STD, and AGR; P = 0.26) and decreased DMI (11.91, 10.74, and 10.89 +/- 0.27 kg/d for CSV, STD, and AGR; P = 0.05), such that G:F was lower for CSV than for STD or AGR (0.105, 0.150, and 0.141 +/- 0.010; P = 0.05). Carcass weight was least for the CSV strategy (298 kg) and greatest for STD (328 kg); AGR resulted in intermediate carcass weight (317 +/- 6 kg; P = 0.04). Total cost of gain was over 30% greater for CSV strategy than for STD or AGR strategies (P < 0.01). In many cases, block effects (age) had a greater effect on responses than treatments. Average daily gain, DMI, and G:F decreased linearly with age (P < 0.01). Hot carcass weight, dressing percent, and fat thickness decreased linearly with age (P < 0.03); yield grade decreased and carcass maturity attributes increased linearly with age (P < 0.02). Performance and intake differences resulted in linear increases in total cost of gain (P < 0.01) and breakeven price (P = 0.03) with increasing age. These data indicate advantages to more aggressive feeding management strategies for culled beef cows, although maximal intake may be achieved with higher-roughage diets. Despite management effects, an increase in market price above purchase price may be required for intensive feeding of culled beef cows to be a profitable enterprise.

Utility of bortezomib retreatment among patients with refractory multiple myeloma

17549

Background: Bortezomib (VELCADE; Vc) has emerged as the standard of care for patients with relapsed or refractory multiple myeloma (MM). However, following initial Vc therapy, its utility in recurrent disease is unclear. This retrospective case series provides preliminary evidence of the safety and efficacy of Vc in the retreatment of patients with recurrent MM. Methods: An observational case series was developed based on a medical records review of all patients (N = 10) who completed Vc retreatment following completion of initial Vc therapy. Best response was measured as the greatest mean % reduction in the treatment response measure: serum/urine M-protein or plasma cells. Differences between initial treatment and retreatment efficacy and Vc-related hospitalizations were assessed using descriptive statistics. Results: During initial treatment 44% of patients responded to Vc (≥50% M-protein (3/9) or plasme cell reduction (1/9, 1 pt NA). At retreatment 50% of patients responded (5/10). Following initial Vc therapy, the median treatment-free interval was just over 13 months (56.6 weeks). One patient experienced a dose reduction due to peripheral neuropathy (grade 2) during retreatment, compared to two patients with neuropathy (grade 3) during initial treatment. Termination of therapy due to any unmanageable toxicity was much lower during retreatment (14.3% vs 62.5%). Finally, none of the patients were hospitalized for Vc-related events during retreatment, compared with two patients during initial treatment. Conclusions: Vc retreatment appears to be as effective as initial treatment in terms of response, and may actually yield less toxicity and hospitalizations. Even though this small sample size precluded statistical testing, the observed patterns are instructive and additional prospective trials are currently ongoing. However, based on these preliminary data, prolonged disease control may be achieved with repeated use.

[Table: see text]

Thiobarbituric Acid Reactive Substances and Volatile Compounds in Chicken Breast Meat Infused with Plant Extracts and Subjected to Electron Beam Irradiation

The effect of irradiation on thiobarbituric acid reactive substances (TBARS) and volatile compounds in raw and cooked nonirradiated and irradiated chicken breast meat infused with green tea and grape seed extracts was investigated. Chicken breast meat was vacuum infused with green tea extract (3,000 ppm), grape seed extract (3,000 ppm), or their combination (at a total of 6,000 ppm), irradiated with an electron beam, and stored at 5 degrees C for 12 d. The targeted irradiation dosage was 3.0 kGy and the average absorbed dosage was 3.12 kGy. Values of TBARS and volatile compound contents of raw and cooked chicken meat were determined during the 12-d storage period. Thiobarbituric acid reactive substances values ranged from 15.5 to 71.4 mg of malondialdehyde/kg for nonirradiated raw chicken and 17.3 to 80.1 mg of malondialdehyde/kg for irradiated raw chicken. Values for cooked chicken ranged from 31.4 to 386.2 and 38.4 to 504.1 mg of malondialdehyde/kg for nonirradiated and irradiated chicken, respectively. Irradiation increased TBARS and hexanal values of controls and meat infused with plant extracts. Hexanal had the highest intensity of volatiles followed by pentanal and other volatiles. Cooking the samples significantly (P < 0.05) increased the amounts of TBARS and volatiles. Addition of plant extracts decreased the amount of TBARS as well as hexanal and pentanal values. Although irradiation increases lipid oxidation, infusion of chicken meat with plant extracts could reduce lipid oxidation caused by irradiation.

Evaluation of an automated deformable image matching method for quantifying lung motion in respiration-correlated CT images

We have evaluated an automated registration procedure for predicting tumor and lung deformation based on CT images of the thorax obtained at different respiration phases. The method uses a viscous fluid model of tissue deformation to map voxels from one CT dataset to another. To validate the deformable matching algorithm we used a respiration-correlated CT protocol to acquire images at different phases of the respiratory cycle for six patients with nonsmall cell lung carcinoma. The position and shape of the deformable gross tumor volumes (GTV) at the end-inhale (EI) phase predicted by the algorithm was compared to those drawn by four observers. To minimize interobserver differences, all observers used the contours drawn by a single observer at end-exhale (EE) phase as a guideline to outline GTV contours at EI. The differences between model-predicted and observer-drawn GTV surfaces at EI, as well as differences between structures delineated by observers at EI (interobserver variations) were evaluated using a contour comparison algorithm written for this purpose, which determined the distance between the two surfaces along different directions. The mean and 90% confidence interval for model-predicted versus observer-drawn GTV surface differences over all patients and all directions were 2.6 and 5.1 mm, respectively, whereas the mean and 90% confidence interval for interobserver differences were 2.1 and 3.7 mm. We have also evaluated the algorithm's ability to predict normal tissue deformations by examining the three-dimensional (3-D) vector displacement of 41 landmarks placed by each observer at bronchial and vascular branch points in the lung between the EE and EI image sets (mean and 90% confidence interval displacements of 11.7 and 25.1 mm, respectively). The mean and 90% confidence interval discrepancy between model-predicted and observer-determined landmark displacements over all patients were 2.9 and 7.3 mm, whereas interobserver discrepancies were 2.8 and 6.0 mm. Paired t tests indicate no significant statistical differences between model predicted and observer drawn structures. We conclude that the accuracy of the algorithm to map lung anatomy in CT images at different respiratory phases is comparable to the variability in manual delineation. This method has therefore the potential for predicting and quantifying respiration-induced tumor motion in the lung.

Ethnic differences in the relationships between obesity and glucose-metabolic abnormalities: a cross-sectional population-based study

OBJECTIVES

To evaluate whether body mass index (BMI) and other anthropometric indices of visceral obesity vary by ethnic group in their distribution and their relationship to metabolic abnormalities.

DESIGN

Cross-sectional study.

PARTICIPANTS

Canadian men and women, aged 35-75 years, of South Asian (n=342), Chinese (n=317), European (n=326) and Aboriginal (n=301) descent were recruited using stratified random sampling.

PRIMARY MEASURES

Anthropometric indices (BMI, waist to hip ratio (WHR) and waist circumference (WC)), metabolic markers (fasting glucose, HbA1c, the ratio of total cholesterol/HDL) and clinical markers (systolic blood pressure) were assessed.

RESULTS

In subjects with BMI<30 kg/m2, the mean marker levels in people with elevated WC (>88 cm in women, >102 cm in men) vs people with normal WC were 6.16 vs 5.34 mmol/l for fasting glucose, 6.05 vs 5.66% for HbA1c and 5.46 vs 4.68 for the ratio of total cholesterol to HDL (P<0.001 in each case). At nearly every given level of BMI, non-European ethnic groups displayed significantly higher marker levels than Europeans. For example, for a given BMI, age and sex, the difference between European and non-European groups in HbA1c levels was 0.53% (95% confidence interval (CI): 0.37-0.69) for South Asians, 0.37% (95% CI: 0.2-0.54) for Chinese and 0.95% (95% CI: 0.78-1.12) for Aboriginal People.

CONCLUSIONS

Uniform cut-points for the classification of obesity using BMI, WHR or WC result in marked variation in the levels of glucose-metabolic abnormalities between ethnic groups. Existing action thresholds for these anthropometric indices do not apply to non-European ethnic groups and warrant revision.

International Council for Standardization in Haematology (ICSH) recommendations for "surrogate reference" method for the packed cell volume

The spun packed cell volume (PCV, hematocrit) is a key measurement on which are based hematology instrument calibration, reference range determination, and assignment of values to calibrators/controls. In 2001, the International Council for Standardization in Haematology (ICSH) recommended a Reference PCV method, which is fully traceable to the ICSH reference hemoglobin method. Because of its complexity, however, this method is impractical for occasional use in routine laboratories and is therefore intended primarily for use by manufacturers of capillary microhematocrit tubes, liquid calibrators, and multichannel analyzers. In response to the need for a simpler method--accessible to all routine laboratories--the ICSH offers this "Surrogate Reference" PCV procedure. It is traceable to the original ICSH Reference PCV method and is based on spun PCVs obtained using borosilicate capillary tubes with an already-known relationship to this reference procedure. This ICSH "Surrogate Reference" PCV method is substantially simpler, thus putting it within the reach of most routine hematology laboratories.

The Quality Assurance programme of the Radiotherapy Group of the European Organization for Research and Treatment of Cancer (EORTC): a critical appraisal of 20 years of continuous efforts

In 1982, the European Organization for Research and Treatment of Cancer (EORTC) Radiotherapy Group established the Quality Assurance (QA) programme. During the past 20 years, QA procedures have become a major part of the activities of the group. The methodology and steps of the QA programme over the past 20 years are briefly described. Problems and conclusions arising from the results of the long-lasting QA programme in the EORTC radiotherapy group are discussed and emphasised. The EORTC radiotherapy group continues to lead QA in the European radiotherapy community. Future challenges and perspectives are proposed.

A multi-disciplinary professional practice model: supporting autonomy and accountability in program-based structure

This article addresses the challenge of maintaining high quality patient care in a large, diverse health care organization as it merged and moved from a functional to a program-based management structure. The article describes the Professional Practice Model (PPM) which was developed to address the professional issues inherent in a program-based management structure. The operationalization of the PPM, including the committee structures which were put in place to support it, are discussed. The final section of the article highlights the strengths and challenges which have arisen through the development and implementation of the Professional Practice Model.

Cholinergic influences on use-dependent plasticity

Motor practice elicits use-dependent plasticity in humans as well as in animals. Given the influence of cholinergic neurotransmission on learning and memory processes, we evaluated the effects of scopolamine (a muscarinic receptor antagonist) on use-dependent plasticity and corticomotor excitability in a double-blind placebo-controlled randomized design study. Use-dependent plasticity was substantially attenuated by scopolamine in the absence of global changes in corticomotor excitability. These results identify a facilitatory role for cholinergic influences in use-dependent plasticity in the human motor system.

Protective effect of pregnancy for development of uterine leiomyoma

Many factors that can modulate the risk of developing uterine leiomyoma have been identified, including parity. Epidemiological data on decreased risk of developing this disease has been subject to different interpretations regarding whether pregnancy per se is protective or, as leiomyomas are a major cause of infertility, women that develop these tumors are less fertile and thus have lower pregnancy rates. We have utilized an animal model genetically predisposed to uterine leiomyoma to investigate the potential protective effect of pregnancy on the risk of developing this disease. Female Eker rats that carry a mutation in the tuberous sclerosis 2 (Tsc-2) tumor suppressor gene develop uterine leiomyoma with a frequency of 65% when nulliparous. These animals were bred with intact or vasectomized males and tumor incidence determined after a single pregnancy (to confirm fertility) or multiple pregnancies over the lifetime of the animals. Females with multiple litters displayed a dramatic shift in tumor incidence and presentation. Tumor incidence decreased from 71% in single litter females to 10% in females that had multiple litters (average: five litters/animal). Interestingly, females bred with vasectomized males also exhibited a reduced tumor incidence of 41%, suggesting that the hormonal changes associated with early stages of pregnancy that occur in pseudopregnant females may have contributed to the protective effect of pregnancy.

Cardiovascular T2-star (T2*) magnetic resonance for the early diagnosis of myocardial iron overload

AIMS

To develop and validate a non-invasive method for measuring myocardial iron in order to allow diagnosis and treatment before overt cardiomyopathy and failure develops.

METHODS AND RESULTS

We have developed a new magnetic resonance T2-star (T2*) technique for the measurement of tissue iron, with validation to chemical estimation of iron in patients undergoing liver biopsy. To assess the clinical value of this technique, we subsequently correlated myocardial iron measured by this T2* technique with ventricular function in 106 patients with thalassaemia major. There was a significant, curvilinear, inverse correlation between iron concentration by biopsy and liver T2* (r=0.93, P<0.0001). Inter-study cardiac reproducibility was 5.0%. As myocardial iron increased, there was a progressive decline in ejection fraction (r=0.61, P<0.001). All patients with ventricular dysfunction had a myocardial T2* of <20 ms. There was no significant correlation between myocardial T2* and the conventional parameters of iron status, serum ferritin and liver iron. Multivariate analysis of clinical parameters to predict the requirement for cardiac medication identified myocardial T2* as the most significant variable (odds ratio 0.79, P<0.002).

CONCLUSIONS

Myocardial iron deposition can be reproducibly quantified using myocardial T2* and this is the most significant variable for predicting the need for ventricular dysfunction treatment. Myocardial iron content cannot be predicted from serum ferritin or liver iron, and conventional assessments of cardiac function can only detect those with advanced disease. Early intensification of iron chelation therapy, guided by this technique, should reduce mortality from this reversible cardiomyopathy.

Spatial and temporal expression of the Cre gene under the control of the MMTV-LTR in different lines of transgenic mice

Cre-loxP based gene deletion approaches hold great promise to enhance our understanding of molecular pathways controlling mammary development and breast cancer. We reported earlier the generation of transgenic mice that express the Cre recombinase under the control of the mouse mammary tumor virus (MMTV) long terminal repeat (LTR). These mice have become a valuable research tool to delete genes specifically in the mammary gland, other secretory organs, and the female germline. We have now characterized in depth the expression of the MMTV-Cre transgene using the ROSA26-lox-Stop-lox-LacZ reporter strain to determine the temporal and spatial activation of Cre on the level of single cells. Our results show that MMTV-mediated Cre-activation is restricted to specific cell types of various secretory tissues and the hematopoietic system. Secondly, the timing of Cre expression varies between tissues and cell types. Some tissues express Cre during embryonic development, while other selected cell types highly activate Cre around puberty, suggesting a strong influence of steroid hormones on the transcriptional activation of the MMTV-LTR. Thirdly, Cre expression in the female germline is restricted to individual mouse lines and is therefore dependent on the site of integration of the transgene. Information provided by this study will guide the researcher to those cell types and developmental stages at which a phenotype can be expected upon deletion of relevant genes.

Double-blind, randomized trial of bupropion SR for the treatment of neuropathic pain

OBJECTIVE

To evaluate the effectiveness and safety of bupropion sustained-release (SR) for the treatment of neuropathic pain.

METHOD

This single-center, outpatient, randomized, double-blind, placebo-controlled, crossover study consisted of two phases. Forty-one nondepressed patients with neuropathic pain spent 6 weeks in each phase in random order and received identical tablets of 150 mg bupropion SR or placebo. Patients were instructed to take one tablet once daily for 1 week followed by one tablet twice daily for 5 weeks.

RESULTS

While the patients took bupropion SR, neuropathic pain relief was improved or much improved in 30 (73%) patients, and one of these patients became pain-free. The mean average pain score at baseline was 5.7, which remained unchanged at the end of week 6 with placebo, but decreased by 1.7 points to 4.0 (p < 0.001) during therapy with bupropion SR. Pain relief with bupropion SR was significant at week 2 (p < 0.05) and continued throughout weeks 3 through 6 (p < 0.001). A significant decrease in interference of pain on quality of life was observed while patients were receiving bupropion SR compared with placebo. Side effects experienced with bupropion SR were not dose-limiting and consisted primarily of dry mouth, insomnia, headache, gastrointestinal upset, tremor, constipation, and dizziness.

CONCLUSION

This placebo-controlled crossover trial showed that bupropion SR (150-300 mg daily) was effective and well tolerated for the treatment of neuropathic pain.

The stability of corneal topography in the post-blink interval

PURPOSE

Videokeratoscopes provide a wealth of information about the topography of the ocular surface. Although there have been numerous studies of the accuracy and precision of videokeratoscopes with inanimate test objects, little information exists on their precision (repeatability) for real eyes.

METHODS

To investigate the stability of the ocular surface in the inter-blink period, 10 patients were recruited for videokeratoscopy. Tear break-up time was measured and videokeratographs were acquired immediately post-blink and again at 4, 8, and 12 seconds post-blink. To permit statistical inferences to be drawn from the data, we acquired 24 videokeratographs for each of the four post-blink intervals. The videokeratograph data were interpolated (bilinear) to a common grid, and average and standard deviation (SD) maps were derived for each post-blink condition. t Tests were used to test the significance of changes observed in the topography.

RESULTS

The instantaneous power SD maps showed increasing variation toward the periphery, with most maps showing less than +/-0.5 diopters (D) of SD in the central 4 to 5 mm and variation in the periphery often reaching more than +/-1 D SD at the edge of an 8-mm diameter. When the 4-, 8-, and 12-second average maps were subtracted from the average map acquired immediately after blinking, regions of statistically significant ( p < 0.001) change were apparent in the upper and lower regions of the maps. The upper and lower bands of change were found to correlate with the natural position of the patients' lid margins.

CONCLUSIONS

For normal eyes, the central regions of videokeratographs show high stability in the inter-blink period. However, the upper and lower edges of 8-mm diameter maps show statistically significant variability, which appears to be related to the effects of eyelid pressure.

STAT4 and STAT6 regulate systemic inflammation and protect against lethal endotoxemia

Members of the signal transducer and activator of transcription (STAT) family are transcription factors that mediate many of the effects of pro- and anti-inflammatory cytokines. The progressive systemic inflammatory response induced by endotoxin is mediated by overzealous cytokine production. Here we identify STAT4 and STAT6 as critical regulators of the systemic inflammatory response to endotoxin. Mice deficient for STAT4 or STAT6 were highly susceptible to lethal endotoxemia. In STAT4(-/-) mice, antibody blockade of IL-12 prevented mortality, suggesting that STAT4 confers protection, while another signaling pathway mediates the detrimental effects of IL-12. In STAT6(-/-) mice we observed dysregulated activation of the transcription factor NF-kappaB, resulting in augmented production of proinflammatory cytokines and chemokines. Furthermore, STAT6(-/-) mice displayed increased organ accumulation of leukocytes and significant hepatocellular injury. These findings demonstrate that STAT4 and STAT6 confer protection against endotoxin-induced death and that for STAT6 these protective effects occur through the regulation of NF-kappaB activation and subsequent production of proinflammatory cytokines and chemokines.

Two cases of Kaposi's sarcoma mimicking Stewart-Treves syndrome found to be human herpesvirus-8 positive

Although angiosarcoma is the most frequent tumor arising in the clinical setting of chronic lymphedema, as in Stewart-Treves syndrome, Kaposi's sarcoma has also been reported in this setting, although rarely. We describe two women who developed Kaposi's sarcoma in the lymphedematous arm many years after surgery for breast cancer. Case 1 is a 92-year-old and Case 2 is an 81-year-old; they underwent left total mastectomy and axillary node dissection for infiltrating breast carcinoma in 1981 and 1982 respectively. At that time, neither patient received further treatment. Except for persistent lymphedema, both women did well until over fourteen years later when each noted the development of several purple asymptomatic plaques on the edematous arm. In both, the clinical diagnosis at the time of biopsy was angiosarcoma. However, histologic findings in both cases were typical for Kaposi's sarcoma. In addition, a nested polymerase chain reaction (PCR) for the detection of a 233bp segment of KSHV/HHV8 was performed on DNA extracted from the paraffin-embedded specimens and both cases were positive for this sequence. Histologic sections of both cases were also tested for KSHV by in situ hybridization and demonstrated a positive signal in the lesional cells in each case.

Neuropsychological clusters within intelligence levels for learning disabled children

The present study assessed 1142 learning disabled children with the Halstead Reitan Neuropsychological Battery and the Wechsler Intelligence Scale for Children-Revised. Subjects were divided into four groups based upon Full Scale IQ (i.e., 70-79; 80-89; 90-99 and 100-110). Subsequent clustering of the test data within each group suggested that while the students in the 70-79 IQ range were represented by a single Impaired Cluster, each of the other IQ groups had both an Impaired Cluster and a Non-Impaired Cluster.

Additive hypotensive and anti-albuminuric effects of angiotensin-converting enzyme inhibition and angiotensin receptor antagonism in diabetic spontaneously hypertensive rats

Angiotensin II plays a pivotal role in the development of diabetic nephropathy, but it remains controversial as to the best approach to effectively block the actions of this hormone in the kidney. The aim of the present study was to explore the effects of long-term treatment (8 months) with a combination of an angiotensin type 1 (AT1) receptor antagonist, irbesartan (15 mg/kg per day), and an angiotensin-converting enzyme (ACE) inhibitor, captopril (100 mg/kg per day), in diabetic spontaneously hypertensive rats. Captopril treatment reduced blood pressure (163+/-3 mmHg versus diabetic 201+/-3 mmHg), but not albumin excretion rate (43.8x//1.3 mg/day versus diabetic 46.8x//1.4 mg/day). Irbesartan treatment was associated with a similar reduction in blood pressure (173+/-3 mmHg) to captopril, and albumin excretion rate was reduced (14x//1.5 mg/day). The combination of irbesartan and captopril induced further reductions in blood pressure (140+/-3 mmHg) and albumin excretion rates (4.0x//1.5 mg/day). Gene expression of transforming growth factor beta-1 was reduced by all treatments to a similar level as assessed by in situ hybridization. These results demonstrate the additive hypotensive and anti-albuminuric effects of an ACE inhibitor and an AT1 receptor, suggesting that combination therapy is an approach not only more effective at reducing blood pressure, but also at retarding the development of diabetic nephropathy.

Involvement of hematopoietic progenitor kinase 1 in T cell receptor signaling

Hematopoietic progenitor kinase 1 (HPK1), a mammalian Ste20-related serine/threonine protein kinase, is a hematopoietic-specific upstream activator of the c-Jun N-terminal kinase. Here, we provide evidence to demonstrate the involvement of HPK1 in T cell receptor (TCR) signaling. HPK1 was activated and tyrosine-phosphorylated with similar kinetics following TCR/CD3 or pervanadate stimulation. Co-expression of protein-tyrosine kinases, Lck and Zap70, with HPK1 led to HPK1 activation and tyrosine phosphorylation in transfected mammalian cells. Upon TCR/CD3 stimulation, HPK1 formed inducible complexes with the adapters Nck and Crk with different kinetics, whereas it constitutively interacted with the adapters Grb2 and CrkL in Jurkat T cells. Interestingly, HPK1 also inducibly associated with linker for activation of T cells (LAT) through its proline-rich motif and translocated into glycolipid-enriched microdomains (also called lipid rafts) following TCR/CD3 stimulation, suggesting a critical role for LAT in the regulation of HPK1. Together, these results identify HPK1 as a new component of TCR signaling. T cell-specific signaling molecules Lck, Zap70, and LAT play roles in the regulation of HPK1 during TCR signaling. Differential complex formation between HPK1 and adapters highlights the possible involvement of HPK1 in multiple signaling pathways in T cells.

Family processes in adolescent depression

A developing body of research points to the role of family relationships and interactions as factors relevant to understanding unipolar depressive symptomatology and disorder in adolescents. This paper is focused on examining mechanisms by which adverse family processes may operate to increase adolescents' vulnerability to depression. The review is organized into a description and evaluation of four potential mechanisms by which families may influence adolescents' risk: (a) Stress/Support, (b) Social Interactional, (c) Cognitive, and (d) Affect Regulation. The presentation of the individual mechanisms is followed by a brief discussion of how they could be integrated to develop a fuller understanding of familial processes relevant to the etiology and maintenance of depressive conditions. Finally, we conclude with a discussion of overall limitations in the literature and recommendations for future research.

An interlaboratory study of a candidate reference method for platelet counting

A multinational interlaboratory task force explored the important variables of platelet reference counting and developed a candidate flow cytometric reference method based on the RBC/platelet ratio. A multicenter comparison was performed to determine whether the method met the necessary criteria and was precise enough to be recommended as a new reference method. Each laboratory analyzed serial dilutions of normal specimens, stabilized material, and at least 60 patient specimens with a range of platelet counts from 1 to 400 x 10(3)/microL (1-400 x 10(9)/L). Pooled analysis of the serial dilutions showed that RBC-platelet and RBC-RBC coincidence events became negligible at sufficiently high dilutions (i.e., > 1:1,000). All laboratories demonstrated excellent intra-assay and acceptable interlaboratory precision. Two antibodies (CD61 and CD41) were used for identifying platelets and individually gave acceptable results, but in a minority of samples, staining differences were observed. The optimum method thus uses a double-labeling procedure with a final dilution factor of 1:1,000. The study demonstrated that this method meets the criteria for a reference platelet count.

A method to develop a nursing intervention: the contribution of qualitative studies to the process

AIM OF THE PAPER

To describe how to develop a patient-centred nursing intervention (NI).

BACKGROUND

The stimulus for scrutinizing methods and techniques to develop a NI was a research project concerning the contribution of information and support to the sexual adaptation of women with gynaecological cancer. Within this project, a NI for sexual teaching (ST) was developed because the literature review revealed no tested NI for this purpose. How patients experience and perceive received information influences the usefulness and efficacy of a teaching intervention. Qualitative methods provide insight and understanding of patients' experience. Consequently, qualitative methods are appropriate to use when developing interventions that aim to influence patients' situations through the provision of information.

METHOD

Previously reported approaches for developing an intervention did not match the goals and underlying premises identified for the intervention under development. An alternative method, consisting of a design phase and a testing phase, was developed. The goal of the design phase was to develop a working definition of the intervention and to formulate recommendations for carrying out the intervention. Written guidelines provided concrete examples of the topics to discuss and how to discuss them. During the design phase, a qualitative study was conducted to describe the lived-experience of the phenomenon that the information should influence, namely sexuality after treatment for gynaecological cancer. In the testing phase, a different type of qualitative study took place. The patients' experience of receiving information and the nurses' experience of providing it were investigated in order to refine the proposed intervention, to identify the results patients hope to achieve (or achieved) and to explore the underlying theoretical explanation of the intervention. During the testing phase, the feasibility and acceptability of the modified intervention were both established.

CONCLUSION

Even when the starting point is advice from care-givers, an intervention can be developed that is in harmony with the patient perspective when qualitative studies are part of the process.

External audits of electron beams using mailed TLD dosimetry: preliminary results

AIM

A feasibility study has been performed to investigate the possibility of using mailed thermoluminescence dosimetry (TLD) for external audits of clinical electron beams in Europe.

METHODS

In the frame of the EC Network Project for Quality Assurance in Radiotherapy, instruction sheets and mailing procedures have been defined for mailed TLD dosimetry using the dedicated holder developed by a panel of experts of the International Atomic Energy Agency (IAEA). Three hundred and thirty electron beam set-ups have been checked in the reference centres and some local centres of the EC Network Project and in addition through the centres participating to the EORTC Radiotherapy Group trial 22922.

RESULTS

The mean ratio of measured dose to stated dose is 0.2% and the standard deviation of measured dose to stated dose is 3.2%. In seven beam set-ups, deviations greater than 10% were observed (max. 66%), showing the usefulness of these checks.

CONCLUSION

The results of this feasibility study (instruction sheets, mailing procedures, holder) are presently endorsed by the EQUAL-ESTRO structure in order to offer in the future to all ESTRO members the possibility to request external audits of clinical electron beams.

Solution structure and backbone dynamics of the DNA-binding domain of mouse Sox-5

The fold of the murine Sox-5 (mSox-5) HMG box in free solution has been determined by multidimensional NMR using (15)N-labeled protein and has been found to adopt the characteristic twisted L-shape made up of two wings: the major wing comprising helix 1 (F10--F25) and helix 2 (N32--A43), the minor wing comprising helix 3 (P51--Y67) in weak antiparallel association with the N-terminal extended segment. (15)N relaxation measurements show considerable mobility (reduced order parameter, S(2)) in the minor wing that increases toward the amino and carboxy termini of the chain. The mobility of residues C-terminal to Q62 is significantly greater than the equivalent residues of non-sequence-specific boxes, and these residues show a weaker association with the extended N-terminal segment than in non-sequence boxes. Comparison with previously determined structures of HMG boxes both in free solution and complexed with DNA shows close similarity in the packing of the hydrophobic cores and the relative disposition of the three helices. Only in hSRY/DNA does the arrangement of aromatic sidechains differ significantly from that of mSox-5, and only in rHMG1 box 1 bound to cisplatinated DNA does helix 1 have no kink. Helix 3 in mSox-5 is terminated by P68, a conserved residue in DNA sequence-specific HMG boxes, which results in the chain turning through approximately 90 degrees.

Survey of distance technology use in AACN member schools

The American Association of Colleges of Nursing surveyed its members by using a 104-item instrument to determine the state of the art in distance technology use. Survey results indicated a recent acceleration of course offerings through distance technology at all levels of nursing education. The most cited reason for this was to improve access to nursing education. Resources for distance technology tended to reside in public, rather than private, institutions. Trends were for greater use of video and computer-based technologies. Although technology use is increasing, computers and other technologies are not used in the didactic or clinical educational experience in many schools. Areas for further evaluation are identified.

Optimal modeling of corneal surfaces with Zernike polynomials

Zernike polynomials are often used as an expansion of corneal height data and for analysis of optical wavefronts. Accurate modeling of corneal surfaces with Zernike polynomials involves selecting the order of the polynomial expansion based on the measured data. We have compared the efficacy of various classical model order selection techniques that can be utilized for this purpose, and propose an approach based on the bootstrap. First, it is shown in simulations that the bootstrap method outperforms the classical model order selection techniques. Then, it is proved that the bootstrap technique is the most appropriate method in the context of fitting Zernike polynomials to corneal elevation data, allowing objective selection of the optimal number of Zernike terms. The process of optimal fitting of Zernike polynomials to corneal elevation data is discussed and examples are given for normal corneas and for abnormal corneas with significant distortion. The optimal model order varies as a function of the diameter of the cornea.

Metabolic abnormalities and cardiovascular disease risk factors in adults with human immunodeficiency virus infection and lipodystrophy

We evaluated metabolic and clinical features of 71 HIV-infected patients with lipodystrophy by comparing them with 213 healthy control subjects, matched for age and body mass index, from the Framingham Offspring Study. Thirty HIV-infected patients without fat redistribution were compared separately with 90 matched control subjects from the Framingham Offspring Study. Fasting glucose, insulin, and lipid levels; glucose and insulin response to standard oral glucose challenge; and anthropometric measurements were determined. HIV-infected patients with lipodystrophy demonstrated significantly increased waist-to-hip ratios, fasting insulin levels, and diastolic blood pressure compared with controls. Patients with lipodystrophy were more likely to have impaired glucose tolerance, diabetes, hypertriglyceridemia, and reduced levels of high-density lipoprotein (HDL) cholesterol than were controls. With the exception of HDL cholesterol level, these risk factors for cardiovascular disease (CVD) were markedly attenuated in patients without lipodystrophy and were not significantly different in comparison with controls. These data demonstrate a metabolic syndrome characterized by profound insulin resistance and hyperlipidemia. CVD risk factors are markedly elevated in HIV-infected patients with fat redistribution.

Experimental infection of chickens as candidate sentinels for West Nile virus

We evaluated the susceptibility, duration and intensity of viremia, and serologic responses of chickens to West Nile (WN) virus (WNV-NY99) infection by needle, mosquito, or oral inoculation. None of 21 infected chickens developed clinical disease, and all these developed neutralizing antibodies. Although viremias were detectable in all but one chicken, the magnitude (mean peak viremia <10,000 PFU/mL) was deemed insufficient to infect vector mosquitoes. WNV-NY99 was detected in cloacal and/or throat swabs from 13 of these chickens, and direct transmission of WNV-NY99 between chickens occurred once (in 16 trials), from a needle-inoculated bird. Nine chickens that ingested WNV-NY99 failed to become infected. The domestic chickens in this study were susceptible to WN virus infection, developed detectable antibodies, survived infection, and with one exception failed to infect cage mates. These are all considered positive attributes of a sentinel species for WN virus surveillance programs.