Implementation of circulating tumour DNA multi-target mutation testing in plasma: a perspective from an external quality assessment providers' survey

Demand for large-scale tumour profiling across cancer types has increased in recent years, driven by the emergence of targeted drug therapies. Analysing alternations in plasma circulating tumour DNA (ctDNA) for cancer detection can improve survival; ctDNA testing is recommended when tumour tissue is unavailable. An online survey of molecular pathology testing was circulated by six external quality assessment members of IQN Path to registered laboratories and all IQN Path collaborative corporate members. Data from 275 laboratories across 45 countries were collected; 245 (89%) perform molecular pathology testing, including 177 (64%) which perform plasma ctDNA diagnostic service testing. The most common tests were next-generation sequencing-based (n = 113). Genes with known stratified treatment options, including KRAS (n = 97), NRAS (n = 84), and EGFR (n = 130), were common targets. The uptake of ctDNA plasma testing and plans to implement further testing demonstrates the importance of support from a well-designed EQA scheme.

P-334 Are measurements of patient-centeredness of endometriosis care and quality of life in women with endometriosis associated?

Study question

To examine the hypothesis that experiences with patient-centred endometriosis care are associated with the endometriosis-specific quality of life dimensions ‘emotional wellbeing’ and ‘social support’.

Summary answer

Positive associations were found between experienced patient-centeredness of care and the quality of life domains ‘emotional well-being’ and ‘social support’.

What is known already

Women with endometriosis have lower quality of life. Furthermore, research showed that the patient-centeredness of endometriosis care could still be improved. The quality of the provided endometriosis care might impact women’s quality of life, as demonstrated in the field of fertility care. A previous explorative study identified associations between patient-centred endometriosis care and two in five dimensions of endometriosis-specific quality of life (i.e. ‘emotional well-being’ and ‘social support’) but concluded that a more focussed and adequately powered study was needed.

Study design, size, duration

A secondary regression analysis of two cross-sectional cohort studies was performed. Both studies investigated patient-centeredness of endometriosis care and endometriosis-specific quality of life using respectively the ENDOCARE questionnaire (ECQ) and the Endometriosis Health Profile 30 (EHP-30). In total the data from 300 women was eligible for analysis, exceeding the, according to our power calculation, required sample size of 200 women.

Participants/materials, setting, methods

The participating women all had surgically proven endometriosis and were recruited by one secondary and two tertiary endometriosis clinics in the Netherlands. The regression analysis focused on the previously found association between the ten dimensions of the ECQ and the EHP-30 domains ‘emotional well-being’ and ‘social support’ rather than all five EHP-30 domains. After the Bonferroni correction to limit type I errors, the adjusted p-value was 0.003 (0.05/20).

Main results and the role of chance

The participating women had a mean age of 35.7 years and had predominantly been diagnosed with moderate to severe (68.6%). Regarding the EHP-30 domain ‘emotional well-being’, an association was found with the following five patient-centeredness dimensions: ‘respect for patients’ values, preferences and expressed needs’ (p = 0.046, Beta=0.159), ‘coordination and integration of care’ (p = 0.013, Beta=0.193), ‘information, communication and integration of care’ (p = 0.010, Beta=0.258), ‘emotional support and alleviation of fear and anxiety’ (p = 0.010, Beta=0.178), and ‘continuity and transition’ (p = 0.015, Beta=0.179). None of the associations between the EHP-30 domain ‘emotional well-being’ and a dimension of patient-centred endometriosis care, were significant when compared to the Bonferroni corrected p-value (all p ≥ 0.010). The EHP-30 domain ‘social support’ proved to be significantly associated to the following three dimensions of patient-centered endometriosis care (in order of strength): ‘information, communication and integration of care’ (p < 0.001, Beta=0.436), ‘coordination and integration of care’ (p = 0.001, Beta=0.307), and ‘emotional support and alleviation of fear and anxiety’ (p = 0.002, Beta=0.259).

Limitations, reasons for caution

This cross-sectional studies identified associations rather than proving causality between experiencing less patient-centeredness of care and having lower quality of life. Nevertheless, it is very tangible that some causality exists, either directly or indirectly (e.g. through empowerment) and that by improving patient-centeredness, quality of life might be improved as well.

Wider implications of the findings

Improving the patient-centeredness of endometriosis care was already considered an important goal, but even more so given its association with women’s quality of life, which is increasingly considered the ultimate measure of health care quality.

Trial registration number

not applicable

Establishing guidelines to harmonize tumor mutational burden (TMB): in silico assessment of variation in TMB quantification across diagnostic platforms: phase I of the Friends of Cancer Research TMB Harmonization Project

Background

Tumor mutational burden (TMB), defined as the number of somatic mutations per megabase of interrogated genomic sequence, demonstrates predictive biomarker potential for the identification of patients with cancer most likely to respond to immune checkpoint inhibitors. TMB is optimally calculated by whole exome sequencing (WES), but next-generation sequencing targeted panels provide TMB estimates in a time-effective and cost-effective manner. However, differences in panel size and gene coverage, in addition to the underlying bioinformatics pipelines, are known drivers of variability in TMB estimates across laboratories. By directly comparing panel-based TMB estimates from participating laboratories, this study aims to characterize the theoretical variability of panel-based TMB estimates, and provides guidelines on TMB reporting, analytic validation requirements and reference standard alignment in order to maintain consistency of TMB estimation across platforms.

Methods

Eleven laboratories used WES data from The Cancer Genome Atlas Multi-Center Mutation calling in Multiple Cancers (MC3) samples and calculated TMB from the subset of the exome restricted to the genes covered by their targeted panel using their own bioinformatics pipeline (panel TMB). A reference TMB value was calculated from the entire exome using a uniform bioinformatics pipeline all members agreed on (WES TMB). Linear regression analyses were performed to investigate the relationship between WES and panel TMB for all 32 cancer types combined and separately. Variability in panel TMB values at various WES TMB values was also quantified using 95% prediction limits.

Results

Study results demonstrated that variability within and between panel TMB values increases as the WES TMB values increase. For each panel, prediction limits based on linear regression analyses that modeled panel TMB as a function of WES TMB were calculated and found to approximately capture the intended 95% of observed panel TMB values. Certain cancer types, such as uterine, bladder and colon cancers exhibited greater variability in panel TMB values, compared with lung and head and neck cancers.

Conclusions

Increasing uptake of TMB as a predictive biomarker in the clinic creates an urgent need to bring stakeholders together to agree on the harmonization of key aspects of panel-based TMB estimation, such as the standardization of TMB reporting, standardization of analytical validation studies and the alignment of panel-based TMB values with a reference standard. These harmonization efforts should improve consistency and reliability of panel TMB estimates and aid in clinical decision-making.

P–504 A randomised controlled trial comparing expectant management or intrauterine-insemination in couples with unexplained subfertility and a poor prognosis for natural conception: the impact on health-related-quality-of-life

Study question

Is health-related quality of life (HRQoL) in women with unexplained subfertility and a poor prognosis influenced by expectant management or intrauterine insemination with ovarian stimulation?

Summary answer

HRQoL did not differ, except for the relational domain which was lower after expectant management. Anxiety and depression disorders occurred frequently in both groups.

What is known already

In couples with unexplained subfertility and a poor prognosis, IUI with ovarian stimulation (IUI-OS) is a first line treatment. Not much is known about quality of live or depression and anxiety in these couples. The Fertility Quality of Life (FertiQoL) is reliable for assessment within relational and social domains, the Hospital Anxiety and Depression Scale (HADS) is a reliable tool to detect anxiety and depression disorders.

Study design, size, duration

We performed a multicentre RCT in couples with unexplained subfertility with a poor prognosis of conceiving naturally within one year. Women were allocated 1:1 to six months expectant management or to six months IUI-OS. HRQoL was assessed with standard self-administered psychometric measures with established reliability and validity: FertiQol and HADS. We intended to include 1091 couples but after almost 4 years, the study had to stop due to slow inclusion and therefore lack of funding.

Participants/materials, setting, methods

Between June 2017 and September 2020, we recruited 178 women of wich 92 were assigned expectant management and 86 IUI-OS. All women who participated and could read Dutch were eligible for the HRQoL measurements because HRQoL questionnaires in foreign languages were not yet available online. Women completed the questionnaires before randomisation, 3 and 6 months after randomisation. We used mixed model analyses to assess differences between treatment groups and the effect of time.

Main results and the role of chance

One hundred sixty-two women could read Dutch and were invited (162/178 (91%)). Analyzable data of the FertiQol questionnaire were available for 80% (130/162). Compared to women allocated to IUI-OS, women allocated to expectant management had a lower FertiQol score in the relational domain (mean difference –4.3 (95% CI –7.3 to –1.3) but not in the social domain (mean diff van –0.8 (95% CI –4.5 to 2.9).

Data of the HADS questionnaire were available of 156 women (96% (156/162)). Both groups had comparable scores in the Anxiety (mean difference –0.20; 95% CI 0.63; –0.99 to 0.6) and Depressions score (mean difference 0.002; 95% CI –0.67 to 0.67) at all three moments. At baseline, the incidence of an anxiety disorder (definition score 8 or higher) was 19% (30/156) and increased to 30% and 29% at 3 months and 6 months respectively. The incidence of a depression disorder (definition score 8 or higher) was 5% (7/156) and increased to 16% and 18% at 3 months and 6 months respectively. The incidences of anxiety or depression disorders did not differ significantly between expectant management and IUI.

Limitations, reasons for caution

Our randomized controlled trial did not reach the planned sample size. The results are only applicable to women with unexplained subfertility and a poor prognosis and not to all women with unexplained subfertility.

Wider implications of the findings: Although often assumed, IUI-OS does not improve HRQoL compared to expectant management in all domains. IUI might prevent loss of quality of the relationship, but the impact seems small. Future studies should look into the high incidence of anxiety and depression disorders in these women and how to support them.

Trial registration number

Trial register NL5455 (NTR5599)

O-103 The impact of the COVID-19 pandemic on infertility and endometriosis patients in the Netherlands: The use of telemedicine, quality of life and patient-centeredness

Study question

How do infertility patients, endometriosis patients and health care providers rate the virtual care that was provided during the first lockdown of the COVID-19 pandemic?

Summary answer

Patients and health care providers rate telephone- and video consultations as good alternatives during the pandemic but it cannot replace future physical consultations.

What is known already

Virtual alternatives to regular care such as telephone and video consultations are gaining more attention as replacement for physical consultations and are ideal for use in a social distancing situation as the COVID-19 pandemic. However, infertility and endometriosis patients often rely on physical consultations for reassurance as well as for treatments such as artificial reproductive technology and surgery. Not being able to receive these reassurances and treatments may cause stress especially as infertility patients are known to experience a high sense of urgency to obtain treatment. For patients with endometriosis, regular follow-up visits are important for continuity of care.

Study design, size, duration: A cross-sectional cohort study was performed, including 555 patients and 101 health care providers in the field of infertility and endometriosis in the Netherlands. Online questionnaires were sent between May and October 2020.

Participants/materials, setting, methods

Patients with infertility and endometriosis patients from a university hospital and members of the respective national patients organizations, as well as health care providers in the fields of infertility and endometriosis were asked to participate. The questionnaires consisted of demographics, appraisal of telephonic and video consultations (TCs and VCs) and assessment of fertility related quality of life (FertiQoL) and patient-centeredness of endometriosis care (ENDOCARE).

Main results and the role of chance

The questionnaires were completed by 374 infertility patients, 181 endometriosis patients and 101 health care providers. 75.9% of the infertility patients, 64.8% of the endometriosis patients and 82.7% of the health care providers rated TCs as a good alternative for physical consultations during the COVID-19-pandemic. Only 21.3%, 14.8% and 21.3% rated TCs as a good replacement of physical consultations in general. 76.6% and 35.9% of the infertility and endometriosis patients reported to experience an increase in stress due to the altered care during the COVID-19 pandemic. 38.7% and 58.0% reported to have received sufficient information from their care givers. Infertility patients scored lower on the FertiQoL than the reference population, while the ENDOCARE results of endometriosis patients were comparable to the reference.

Limitations, reasons for caution

This study was limited to the Dutch population. As the organization of infertility care varies internationally, the results will not be directly applicable to other countries or health care systems.

Wider implications of the findings: Virtual care options are a good alternative for infertility and endometriosis patients in situations where physical consultations are not possible. Self-reported stress is especially high in infertility patients during the COVID-19-pandemic. Health care providers should provide more information to patients in order to increase their ability to cope with stress.

Trial registration number

N/A

P–753 A randomised controlled trial comparing expectant management versus intrauterine insemination in couples with unexplained subfertility and a poor prognosis for natural conception

Study question

Does 6 months expectant management reduces ongoing pregnancy rates compared to intrauterine insemination with ovarian stimulation (IUI-OS) in couples with unexplained subfertility?

Summary answer

In couples with unexplained subfertility and a poor prognosis for natural conception, 6 months of expectant management decreases ongoing pregnancy rates as compared to IUI-OS.

What is known already

In couples with unexplained subfertility and a poor prognosis, IUI-OS is a first line treatment. We have previously shown that in couples with unexplained subfertility and a good prognosis for natural conception (>30% in 12 months), 6 months expectant management does not reduce pregnancy changes. However, in couples with a poor prognosis for natural conception, effectiveness of IUI-OS is uncertain.

Study design, size, duration

We performed a non-inferiority multicentre randomised controlled trial (RCT) within the infrastructure of the Dutch Consortium for Healthcare Evaluation and Research in Obstetrics and Gynaecology. We studied couples with unexplained subfertility and a poor prognosis for natural conception. The couples were allocated in a 1:1 ratio to six months expectant management or six months IUI-OS with either clomiphene citrate or gonadotrophins.

Participants/materials, setting, methods

We intended to include 1091 couples. The trial was halted pre-maturely due to slow inclusion after randomisation of 178 couples. The primary outcome was ongoing pregnancy leading to a live birth with multiple pregnancy and miscarriage rate as important secondary outcomes. We calculated relative risks with 95% CI and a corresponding hazard-rate for ongoing-pregnancy-over-time based on intention-to-treat.

Main results and the role of chance

Between October 2016 and September 2020 92 couples were allocated to expectant management and 86 to IUI-OS. Baseline characteristics were equally distributed. Mean female age was 34 years, median duration of subfertility was 21 months. Within 6 months after randomisation, women allocated to expectant management had a lower ongoing pregnancy rate than women allocated to IUI-OS (12/92 [13.0%] vs 29/86 women [33.7%], risk ratio 0.39 (95%CI 0.21 to 0.71)). There were two ongoing twin pregnancies in the expectant management group versus none in the IUI-OS group. Of 15 clinical pregnancies in the expectant management group three miscarried (20%), of 36 clinical pregnancies in the IUI-OS group seven miscarried (19.4%) (RR 1.03 (95% CI 0.31 to 3.45)). For the outcome ongoing pregnancy, the hazard ratio for expectant management versus IUI-OS was 0.34 (95%CI 0.18 to 0.67).

Limitations, reasons for caution

Our trial did not reach the planned sample size and therefore the results are limited by the number of participants. As 8 women are still pregnant, in this abstract we report ongoing pregnancy rates. Live birth rates will be presented at the conference.

Wider implications of the findings: In couples with unexplained subfertility and a poor prognosis for natural conception, expectant management is inferior to IUI-OS. We advise the basic work-up for subfertility to contain a prognostic assessment, and when subfertility is unexplained and natural fertility prospects are poor IUI-OS should be the preferred treatment.

Trial registration number

NTR5599

Scatter radiation reduction with a radiation-absorbing pad in interventional radiology examinations

PURPOSE

Radiation-absorbing pads are an additional possibility to reduce scattered radiation at its source. The goal of this study is to investigate the efficacy of a new reusable radiation-absorbing pad at its origin in an experimental setup.

MATERIAL AND METHODS

All measurements were carried out using a clinical angiography system with a standardized fluoroscopy protocol, different C-arm angulations and an anthropomorphic torso phantom as a scattering body. An ionization chamber was used to measure the radiation exposure at five different heights of a simulated operator during a simulated transfemoral angiography intervention. Measurements were carried out with and without radiation-absorbing pads with lead equivalents of 0.25 and 0.5 mm placed onto the scattering body. For all measurements a mobile acrylic shield and an under-table lead curtain was used.

RESULTS

At all operator heights from 100 to 165 cm a significant radiation dose reduction of up to 80.6 % (p < 0.01) using the radiation-absorbing pad was measured, when compared to no radiation-absorbing pad. At the height of 165 cm the radiation-absorbing pad with a lead equivalence of 0.5 mm showed a significant radiation dose reduction (51.4 %, p < 0.01) in comparison to a lead equivalence of 0.25 mm.

CONCLUSION

The addition of a radiation-absorbing pad to the standard protection means results in a significant dose reduction for the operator, particularly for upper body parts.

The association between natural outdoor environments and common somatic symptoms

There is growing evidence that urban natural outdoor environments (NOE) may positively impact health by reducing stress and stress-related symptoms. However, there is limited research investigating this link across a range of NOE indicators. This cross-sectional study investigated the association between neighbourhood NOE (availability, use, and satisfaction with NOE) and common somatic symptoms and the role of potential mediators. Data were analysed from 3481 adults from Barcelona (Spain), Doetinchem (Netherlands), Kaunas (Lithuania) and Stoke-on-Trent (United Kingdom). NOE data were obtained through self-reported data and environmental measurements. Common somatic symptom data were self-reported. Mixed effects regression models were used for analysis, with models adjusted for potential sociodemographic confounders. Higher satisfaction with neighbourhood NOE was associated with lower prevalence of common somatic symptoms (exp(β) 0.97; 95% CI 0.96, 0.98); an association partially mediated by mental health, social cohesion and air quality concern. A longer time spent in NOE was associated with lower prevalence of common somatic symptoms in low socioeconomic status neighbourhoods (exp(β) 0.98; 95% CI 0.96, 1.00). A higher number of neighbourhood green spaces (300m buffer) was associated with higher prevalence of common somatic symptoms (exp(β) 1.03; 95% CI 1.00, 1.05). No statistically significant associations were found for other NOE indicators. Study findings suggest that higher satisfaction with NOE may be associated with lower prevalence of common somatic symptoms, with mental health, social cohesion and concern about air quality playing partial mediating roles. Little evidence was found of an association between objective NOE measurements and common somatic symptoms, underlining the importance of perceptions of NOE for conferring health benefits.

Consensus recommendations on calf- and herd-level passive immunity in dairy calves in the United States

Passive immunity in calves is evaluated or quantified by measuring serum or plasma IgG or serum total protein within the first 7 d of age. While these measurements inform about circulating concentrations of this important protein, they are also a proxy for evaluating all of the additional benefits of colostral ingestion. The current individual calf standard for categorizing dairy calves with successful passive transfer or failure of passive transfer of immunity are based on serum IgG concentrations of ≥10 and <10 g/L, respectively. This cutoff was based on higher mortality rates in calves with serum IgG <10 g/L. Mortality rates have decreased since 1991, but the percentage of calves with morbidity events has not changed over the same time period. Almost 90% of calves sampled in the USDA National Animal Health Monitoring System's Dairy 2014 study had successful passive immunity based on the dichotomous standard. Based on these observations, a group of calf experts were assembled to evaluate current data and determine if changes to the passive immunity standards were necessary to reduce morbidity and possibly mortality. In addition to the USDA National Animal Health Monitoring System's Dairy 2014 study, other peer-reviewed publications and personal experience were used to identify and evaluate potential standards. Four options were evaluated based on the observed statistical differences between categories. The proposed standard includes 4 serum IgG categories: excellent, good, fair, and poor with serum IgG levels of ≥25.0, 18.0-24.9, 10.0-17.9, and <10 g/L, respectively. At the herd level, we propose an achievable standard of >40, 30, 20, and <10% of calves in the excellent, good, fair, and poor categories, respectively. Because serum IgG concentrations are not practical for on-farm implementation, we provide corresponding serum total protein and %Brix values for use on farm. With one-third of heifer calves in 2014 already meeting the goal of ≥25 g/L serum IgG at 24 h of life, this achievable standard will require more refinement of colostrum management programs on many dairy farms. Implementation of the proposed standard should further reduce the risk of both mortality and morbidity in preweaned dairy calves, improving overall calf health and welfare.

Proposed dairy calf birth certificate data and death loss categorization scheme

The majority of dairy heifer calves in the United States are destined to be dairy replacements. However, many dairy heifer and bull calves die before 6 mo of age. Of these calves, about 6% (more than 500,000 calves) die at birth or shortly after (i.e., currently termed "stillbirth"). An additional 6% of dairy heifers die during the preweaning period. Death loss in dairy calves is primarily due to stillbirths, failure to adapt to extrauterine life, and infectious disease processes. The reasons for preweaning heifer calf deaths caused by infectious diseases are generally categorized based on easily recognizable clinical signs such as digestive disease/scours or respiratory disease. Most causes of calf death can be mitigated by appropriate preventive care or well-tailored treatments, meaning that the typical death loss percentage could be decreased with better management. Producers could gather information on the circumstances near birth and at death if they had appropriate guidance on what details to record and monitor. This paper provides recommendations on data to collect at the time of birth (i.e., calf birth certificate data). The recording of these critical pieces of information is valuable in evaluating trends over time in morbidity and mortality events in dairy calves. Ideally, necropsy examination would substantially improve the identification of cause of death, but even without necropsy, attribution of cause of death can be improved by more carefully defining death loss categories in on-farm record systems. We propose a death loss categorization scheme that more clearly delineates causes of death. Recommendations are provided for additional data to be collected at the time of death. Recording and analyzing birth certificate and death loss data will allow producers and veterinarians to better evaluate associations between calf risk factors and death, with the goal of reducing dairy calf mortality.

Autonomy deficits as vulnerability for anxiety: evidence from two laboratory-based studies

BACKGROUND

Autonomous individuals are characterized by self-governance; awareness of and capacity to realize one's wishes and needs, while being connected with and sensitive towards others. In line with earlier research showing consistent associations between autonomy-connectedness deficits and anxiety, we tested in two studies whether autonomy deficits predict anxious responses to acute stressors.

METHODS

In Study 1, participants (N = 177) viewed an anxiety-inducing film fragment and reported anxiety before and after viewing the clip. In experimental Study 2, participants (N = 100) were randomly allocated to one of two conditions: giving a short presentation to an audience (impromptu speech task) or watching another person's presentation (control condition). Anxiety was measured at baseline, after a preparation period and directly after the presentation.

RESULTS

In Study 1, individuals' anxiety in reaction to watching the movie was positively associated with the autonomy-connectedness component sensitivity to others. In Study 2, individuals' anxiety in reaction to preparing the presentation was negatively associated with the autonomy-connectedness component self-awareness.

CONCLUSIONS

Specific autonomy components may be related to experiencing anxiety in differing situations (i.e., related to others' distress or presenting one's personal views). Collectively these results indicate that autonomy-connectedness deficits may form a vulnerability factor for experiencing anxiety.

Autonomy–Connectedness, Self-Construal, and Acculturation: Associations With Mental Health in a Multicultural Society

The present study investigated the associations between self-construal, acculturation, and autonomy–connectedness, as well as the relations between autonomy–connectedness and psychopathological symptoms, controlling for self-construal and acculturation. Participants were 1,209 Dutch individuals, of whom 693 (57.3%) were immigrants with a non-Western background. Results showed that an independent self-construal was positively associated with self-awareness and capacity for managing new situations, and was negatively associated with sensitivity to others (which are the three components of autonomy–connectedness). Moreover, an interdependent self-construal was negatively associated with self-awareness and capacity for managing new situations, and was positively associated with sensitivity to others. Importantly, the latter associations were similar for both Dutch natives and immigrants, and the associations between acculturation and autonomy–connectedness were small and nonsignificant. Autonomy–connectedness, after controlling for self-construal and acculturation, explained a large amount of additional variance in anxiety (12.7%) and depression (14.1), and a medium amount of additional variance in drive for thinness (3.7%) and bulimia (4.8%). Autonomy–connectedness, thus, seems to be an important construct for people with a Western background, as well as for immigrants with a non-Western background.

Social neighborhood environment and sports participation among Dutch adults: does sports location matter?

Studies on the relation between the social neighborhood environment and sports participation have produced inconsistent results. Use of generic sports outcomes may have obscured associations only apparent for sports at certain locations. This study aims to assess the association between the social neighborhood environment and three location-specific sports outcomes. Repeated cross-sectional data on sports participation (any type of sports, sports at indoor sports clubs, sports at outdoor sports clubs, sports on streets) were obtained from 20 600 adults using the Dutch national health survey 2006-2009. Data on neighborhood social safety and social capital were obtained using the Dutch Housing Research 2006. Over 40% of Dutch adults participated in any type of sports. Indoor sports clubs were most popular. Multilevel logistic regression analyses revealed that neighborhood social safety was positively associated with sports at indoor sports clubs [odds ratio (OR) = 1.25, 95% confidence interval (CI) = 1.06-1.48), but not with the other sports outcomes. Contrary, neighborhood social capital was positively associated with sports on streets only (OR = 1.69, 95% CI = 1.17-2.44). The results suggest that a positive social neighborhood environment enhances sports participation, but that this impact depends on the location of the sports activity. This study highlights the importance of using location-specific sports outcomes when assessing environmental determinants.

Morbidity is related to a green living environment

BACKGROUND

As a result of increasing urbanisation, people face the prospect of living in environments with few green spaces. There is increasing evidence for a positive relation between green space in people's living environment and self-reported indicators of physical and mental health. This study investigates whether physician-assessed morbidity is also related to green space in people's living environment.

METHODS

Morbidity data were derived from electronic medical records of 195 general practitioners in 96 Dutch practices, serving a population of 345,143 people. Morbidity was classified by the general practitioners according to the International Classification of Primary Care. The percentage of green space within a 1 km and 3 km radius around the postal code coordinates was derived from an existing database and was calculated for each household. Multilevel logistic regression analyses were performed, controlling for demographic and socioeconomic characteristics.

RESULTS

The annual prevalence rate of 15 of the 24 disease clusters was lower in living environments with more green space in a 1 km radius. The relation was strongest for anxiety disorder and depression. The relation was stronger for children and people with a lower socioeconomic status. Furthermore, the relation was strongest in slightly urban areas and not apparent in very strongly urban areas.

CONCLUSION

This study indicates that the previously established relation between green space and a number of self-reported general indicators of physical and mental health can also be found for clusters of specific physician-assessed morbidity. The study stresses the importance of green space close to home for children and lower socioeconomic groups.

Imaging data suggesting acute pyelonephritis in the kidney graft: report of five cases with atypical clinical presentation

Acute pyelonephritis is a common complication of kidney transplantation, occurring in up to 1% of grafts. Diagnosis is mainly clinical and atypical presentations have seldom been reported. The diagnostic role of imaging techniques has not been defined. Five cases of acute graft pyelonephritis are reported (three kidney, two pancreas-kidney grafts). The patients (median age 48 years) comprised three females and two males. Median post-transplant follow-up was 3 months, with three patients having predisposing factors for diabetes and one for an enteric bladder. None of the patients presented the 'classic' diagnostic tetrad (i.e. fever, positive urine cultures, low urinary tract symptoms and serum creatinine increase); although, at diagnosis, two of five patients presented with fever, one had increased creatinine levels and one had positive urine cultures. Of note, three patients had leucocyte casts at urinary sediment analysis, thus raising clinical suspicion. Renal ultrasounds were negative in all patients. Renal (99m)Tc-MAG3 (mercaptoacetyltriglycine) scintigraphy, which was used for the definition of kidney function impairment (one patient) or because of the presence of urinary casts (three patients), or after the biopsy diagnosis to locate the parenchymal lesions (one patient), was positive in all patients. The presence and pyelonephritic origin of the parenchymal lesions was confirmed by nuclear magnetic resonance or computed tomography scans. Acute graft pyelonephritis may develop in the absence of a full-blown clinical picture. Smouldering symptoms may occur in the presence of large perfusion deficits. (99m)Tc-MAG3 scintigraphy could be an important diagnostic tool in such cases.

Endothelial progenitor marker CD133 mRNA expression in peripheral blood mononuclear cells predicts outcome of cancer patients

10087

Background: We examined whether expression of CD133, a surface molecule expressed on progenitors of hematopoietic and endothelial lineages, is increased in the peripheral blood mononuclear cells (PBMC’s) of cancer patients. Furthermore we correlated CD133 mRNA expression with tumor prognostication factors and overall survival. Methods: PBMC’s were isolated from the blood of 130 advanced cancer patients (43 renal cell carcinoma, 27 colorectal cancer, 34 prostate cancer, 27 head and neck cancer). Clinicopathological parameters were obtained. Median follow-up time was 16 months after inclusion (range 3–33 months). For the quantification of CD133 mRNA we used a real-time detection and quantification method based on nucleic acid sequence-based amplification (NASBA). Also U1A DNA was quantified as internal control for input and isolation. CD133 mRNA copy numbers were expressed as copies per 10.000 cells, as determined by U1A DNA. Results: Patients with metastasized disease have a significant increase in CD133 mRNA as compared to patients without metastasis. This increase is strongest in patients with bone metastasis. Subgroup analysis in patients with bone involvement show that CD133 mRNA also correlates with PSA (n=34)and inversely with hemoglobin (n=50). CD133 mRNA expression is an independent predictor for overall survival in Cox’s multivariate analysis (variables in the model included age, hemoglobin, metastasis, previous treatment and CD133 as categorical variable). A CD133 mRNA cut-off value was established by Receiver Operating Characteristic analysis of CD133 expression in relationship to survival (sensitivity 64% and specificity 71%). Cancer patients with more than 200 copies of CD133 mRNA, demonstrate a decreased survival compared to patients with lower CD133 expression (median survival 8 and 15.4 months, respectively). In patients with bone metastasis the median survival of high and low expressers is 6.3 months and 21.9 months, respectively. Conclusions: mRNA expression of stem-cell marker CD133 is increased in cancer patients with metastasized disease and an independent prognostic factor for overall survival. Increased CD133 mRNA expression may reflect an activated angiogenic state in these cancer patients.

[Table: see text]

Durable HIV-1 suppression with indinavir after failing lamivudine-containing double nucleoside therapy: a randomized controlled trial

OBJECTIVE

To assess the durability of the antiretroviral effect in plasma and cerebrospinal fluid (CSF) of antiviral therapy intensification, produced by the addition of indinavir from week 12 onwards to the original regimen of zidovudine/lamivudine or stavudine/lamivudine, after 72 weeks of follow-up using an ultrasensitive HIV-1 RNA assay. To assess CSF concentrations of indinavir at week 48.

DESIGN

In a prospectively, randomized, open, single-centre study, antiretroviral-naive patients (CD4 cell count > or =200 cells/microl and a plasma HIV-1 RNA level 10,000 copies/ml) were assigned to a combination of zidovudine/lamivudine or stavudine/lamivudine. Indinavir could be added to the double nucleoside analogue regimen from week 12 or thereafter in case the plasma HIV RNA level was insufficiently suppressed (>500 copies/ml).

RESULTS

Forty-seven patients were enrolled (23 stavudine/lamivudine and 24 zidovudine/lamivudine), of whom 33 completed a follow-up of 72 weeks. Indinavir was added in 89% (42/47) of the patients. Only one discontinuation occurred due to virological failure. At week 72, the median plasma HIV-1 RNA levels in the zidovudine/lamivudine group had decreased from 4.80 log10 copies/ml to <500 copies/ml in 100% of patients and <50 copies/ml in 86.6% of the patients. In the stavudine/lamivudine group the plasma HIV-1 RNA decreased from 4.98 log10 copies/ml at baseline to <500 copies/ml in 100% of patients and <50 copies/ml in 66.7% of the patients. On an intent-to-treat basis these figures were 54.2 and 52.2% for zidovudine/lamivudine and stavudine/lamivudine, respectively, for the 50 copies/ml assay. The median CD4 cell count increased from 315 cells/microl, with 150 cells/microl in the zidovudine/lamivudine arm, and from 290 cells/microl, with 310 cells/microl in the stavudine/lamivudine arm (P=0.0001). However, the percentage of CD4 cells did not differ in each group. In the zidovudine/lamivudine group 9/10 and 5/5, and in the stavudine/lamivudine group 11/11 and 6/6 had a CSF HIV-1 RNA level <50 copies/ml at week 12 and 48, respectively. The CSF indinavir concentration ranged from 50 to 170 ng/ml.

CONCLUSION

The long-term HIV-1 suppression observed in this study is remarkable, as adding a single antiretroviral agent to a failing regimen goes against current notions of adequate therapy.

Quantitative whole-body autoradiography: recommendations for the standardization of the method

The objective of this article is to identify the best conditions for preparing, handling, and exposing radioactive sections by using the Fujix BAS 2000 system for quantitative radioluminography. Regarding the influence of thickness of sections, thicker sections may allow shorter exposure times due to the increased radioactivity, but on the other hand they take more time for the freeze-drying process, resolution will be reduced, and the recovery of radioactivity will be lower due to increased self-absorption particularly in organs like bones or teeth. The pretreatment of the sections should depend on the method of exposure. Powdering with talcum is the most recommendable method when vacuum packaging the imaging plates and sections. Spraying with Nobecutan is recommended when using the cartridge method. Particularly for low concentrations, the vacuum-contact method should be the method of choice. To avoid a flare effect, the geometrical arrangement of the sections on the imaging plate (IP) should always be vertical to the scanning direction of the laser. An exposure time longer than 10 days is not recommended and the time between the end of exposure and start of scanning should be as short as possible. In order to reduce the background signal, it is necessary to expose the IPs in a shielding box in a cold environment. No positive chemographic effects of sections were found.

Quantitative distribution studies in animals: cross-validation of radioluminography versus liquid-scintillation measurement

The results of a cross-validation of the radioluminography (RLG) and liquid scintillation counting (LSC) methods are presented. The methods for the determination of radioactivity concentrations were compared in 16 organs, after administration of (14)C-labeled substances to rats. LSC measurements of two kinds were used as reference methods for RLG: (1) quantitative determination of radioactivity after conventional dissection (interindividual comparison) and (2) quantitative determination of radioactivity in tissue punches taken from the whole-body sections after they had undergone RLG measurement (intraindividual comparison). Blood standards containing known concentrations were used for calibration. For statistical evaluation log-linear regression analysis of paired concentration values and organ-specific 95% confidence intervals of the log-transformed RLG/LSC concentration quotients were compared. For most organs, the slopes of the regression lines and the means of the concentration quotients were within the defined equivalence range of 0.80-1.25. Deviations were distinctly smaller in the intraindividual comparison. For some organs, however, it became clear that found concentrations were affected by self-absorption (RLG) and by differences in sample preparation (LSC). In conclusion, quantification with RLG is a reliable and reproducible method with comparable measurement precision and greater accuracy in respect of tissue localization, compared to LSC (dissection).

Papio cynocephalus endogenous retrovirus among old world monkeys: evidence for coevolution and ancient cross-species transmissions

To study the evolutionary history of Papio cynocephalus endogenous retrovirus (PcEV), we analyzed the distribution and genetic characteristics of PcEV among 17 different species of primates. The viral pol-env and long terminal repeat and untranslated region (LTR-UTR) sequences could be recovered from all Old World species of the papionin tribe, which includes baboons, macaques, geladas, and mangabeys, but not from the New World monkeys and hominoids we tested. The Old World genera Cercopithecus and Miopithecus hosted either a PcEV variant with an incomplete genome or a virus with substantial mismatches in the LTR-UTR. A complete PcEV was found in the genome of Colobus guereza-but not in Colobus badius-with a copy number of 44 to 61 per diploid genome, comparable to that seen in papionins, and with a sequence most closely related to a virus of the papionin tribe. Analysis of evolutionary distances among PcEV sequences for synonymous and nonsynonymous sites indicated that purifying selection was operational during PcEV evolution. Phylogenetic analysis suggested that possibly two subtypes of PcEV entered the germ line of a common ancestor of the papionins and subsequently coevolved with their hosts. One strain of PcEV was apparently transmitted from a papionin ancestor to an ancestor of the central African lowland C. guereza.

Proteasome inhibitors: a novel class of potent and effective antitumor agents

The ubiquitin-proteasome pathway plays a critical role in the regulated degradation of proteins involved in cell cycle control and tumor growth. Dysregulating the degradation of such proteins should have profound effects on tumor growth and cause cells to undergo apoptosis. To test this hypothesis, we developed a novel series of proteasome inhibitors, exemplified by PS-341, which we describe here. As determined by the National Cancer Institute in vitro screen, PS-341 has substantial cytotoxicity against a broad range of human tumor cells, including prostate cancer cell lines. The PC-3 prostate cell line was, therefore, chosen to further examine the antitumor activity of PS-341. In vitro, PS-341 elicits proteasome inhibition, leading to an increase in the intracellular levels of specific proteins, including the cyclin-dependent kinase inhibitor, p21. Moreover, exposure of such cells to PS-341 caused them to accumulate in the G2-M phase of the cell cycle and subsequently undergo apoptosis, as indicated by nuclear condensation and poly(ADP-ribose) polymerase cleavage. Following weekly i.v. treatment of PS-341 to mice bearing the PC-3 tumor, a significant decrease (60%) in tumor burden was observed in vivo. Direct injection of PS-341 into the tumor also caused a substantial (70%) decrease in tumor volume with 40% of the drug-treated mice having no detectable tumors at the end of the study. Studies also revealed that i.v. administration of PS-341 resulted in a rapid and widespread distribution of PS-341, with highest levels identified in the liver and gastrointestinal tract and lowest levels in the skin and muscle. Modest levels were found in the prostate, whereas there was no apparent penetration of the central nervous system. An assay to follow the biological activity of the PS-341 was established and used to determine temporal drug activity as well as its ability to penetrate tissues. As such, PS-341 was shown to penetrate PC-3 tumors and inhibit intracellular proteasome activity 1.0 h after i.v. dosing. These data illustrate that PS-341 not only reaches its biological target but has a direct effect on its biochemical target, the proteasome. Importantly, the data show that inhibition of this target site by PS-341 results in reduced tumor growth in murine tumor models. Together, the results highlight that the proteasome is a novel biochemical target and that inhibitors such as PS-341 represent a unique class of antitumor agents. PS-341 is currently under clinical evaluation for advanced cancers.

Presence of the variant mannose-binding lectin alleles associated with slower progression to AIDS. Amsterdam Cohort Study

OBJECTIVE

To examine the association between mannose-binding lectin (MBL) polymorphism and progression to AIDS and death in HIV-1 infection.

DESIGN AND METHODS

In 131 HIV-1-infected homosexual seroconverters, survival analyses were performed to determine both the association between MBL genotype and time from HIV-1 seroconversion to AIDS and death, and time from AIDS to death.

RESULTS

Of the 131 seroconverters, of whom 61 developed AIDS, 76 were typed as homozygous wild-type and 55 as carriers of variant alleles (52 heterozygous and three homozygous variant alleles). A Survival analyses suggested that HIV-1-infected men with the variant alleles progressed somewhat slower to AIDS [relative hazard (RH), 0.62; 95% confidence interval (CI), 0.36-1.10] and death (RH, 0.73; 95% CI, 0.42-1.25). Interestingly, CD4+ T-cell count determined at the moment of AIDS was found to be significantly lower among persons with the mutation (97 x 10(6)/l versus 204 x 10(6)/l; P=0.03). Furthermore, when AIDS-free times before the diagnosis of an opportunistic infection were compared with those preceding a diagnosis of Kaposi's sarcoma, Kaposi's sarcoma diagnosis was more postponed than that of an opportunistic infection (RH, 0.21; 95% CI, 0.05-0.95; versus RH, 0.67; 95% CI, 0.35-1.27).

CONCLUSION

Indications for a weak pre-AIDS protective effect of variant MBL alleles were demonstrated.

Water vapor sorption studies on the physical stability of a series of spray-dried protein/sugar powders for inhalation

One theory suggests that by maintaining the protein in an amorphous glassy sugar matrix, the physical hindrance encountered by the protein functions to stabilize it. Thus, the nature of the sugar/protein interaction is important as is the maintenance of the sugar in an amorphous form without any recrystallization. Moisture is known to function as a plasticizer and facilitate crystallization and thus loss of the amorphous state. We report the effect of cospray-drying with different proteins on the physical stability of lactose and mannitol. Particle sizing showed their suitability for inhalation, and the effect of exposure of the spray-dried products to moisture vapor was monitored gravimetrically. Bovine liver catalase, bovine pancreatic insulin, and bovine pancreatic ribonuclease A when individually cospray-dried with lactose showed no extensive initial crystallinity by powder X-ray diffraction, but proteins cospray-dried with mannitol generally showed evidence of mannitol component crystallinity. Catalase appeared to inhibit lactose crystallization from an amorphous matrix to a greater extent than insulin when exposed to short-term elevated humidity, but this difference was a kinetic feature. The hygroscopicities of the cospray-dried materials differed and indicated that each protein/sugar system required individual characterization to identify an optimal formulation.

Human immunodeficiency virus type 1 in faeces and serum: evidence against independently evolving subpopulations

It is not known whether independent tissue-specific evolution accounts for the differences between human immunodeficiency virus type 1 (HIV-1) subpopulations in intestinal tissue and blood. To study this, sequential serum samples from three persons were analysed for the presence of HIV-1 V3 genotypes which were detected exclusively in faeces at a specific time-point. For two persons the faeces genotype was found in serum samples collected before the time of faeces collection: 7 months for one person and 32 months for the other person. In the third person, serum collected 1 month after faeces collection contained the faeces genotype in abundance. These data indicate that a difference between intestinal tissue and blood HIV-1 subpopulations is not the result of complete compartmentalization and independent HIV-1 evolution in intestinal tissue, but that it reflects an unequal distribution of HIV-1 in different tissues.

An open randomized controlled trial of zidovudine plus lamivudine versus stavudine plus lamivudine

OBJECTIVE

To compare the antiretroviral effect and safety of zidovudine (ZDV)-lamivudine (3TC) with that of stavudine (d4T)-3TC.

METHODS

In an open randomized controlled trial antiretroviral therapy-naive patients who had CD4+ counts > or = 200 x 10(6)/l and plasma HIV RNA load > or = 10000 copies/ml were randomized to receive ZDV-3TC (200 mg three times daily and 150 mg twice daily, respectively) or d4T-3TC (40 mg and 150 mg, both twice daily). If the plasma HIV RNA level at week 8 or thereafter was > 500 copes/ml, indinavir was added at the next scheduled visit. Genotypic resistance analysis of the reverse transcriptase gene was performed at week 0 and 12. Results over 24 weeks were reported.

RESULTS

Forty-seven patients were treated (24 took ZDV-3TC; 23 took d4T-3TC). Plasma HIV RNA levels decreased from median 4.80 to 3.15 log10 copies/ml (ZDV-3TC, P < 0.0001) and from 4.98 to 3.03 log10 copies/ml (d4T-3TC, P < 0.0001) after 12 weeks of treatment. Indinavir was added at week 12 in 11 out of 21 patients with ZDV-3TC and in 10 out of 22 patients with d4T-3TC. Median virus load at week 24 was 2.41 log10 and 2.29 log10 copies/ml (P=0.14), respectively. Seventy-five per cent (15 out of 20; ZDV-3TC) and 95% (18 out of 19; d4T-3TC) of patients had a virus load of < 500 copies/ml. Genomic evidence for 3TC resistance was found in all patients tested (11/11 ZDV-3TC and 12/12 d4T-3TC). At week 12, CD4 cell counts had increased with a median of 110 x 10(6)/l in the ZDV-3TC group (baseline, 315 x 10(6)/l) and a median of 115 x 10(6)/l in the d4T-3TC group (baseline 290 x 10(6)/l). At week 24, the median increases were 90 and 120 x 10(6)/l, respectively. Overall the increase of CD4+ cells was higher in the d4T-3TC group (P=0.02).

CONCLUSION

d4T-3TC is at least as effective as ZDV-3TC, but 3TC resistance emerged in all patients investigated. The virological response of the dual nucleoside combination is of short duration. However, after addition of indinavir the virus load could be reduced to < 500 copies/ml in the majority of patients. The increase in CD4+ cell count was significantly greater in the d4T-3TC group. To prevent 3TC resistance, the drug should not be used in regimens containing only two nucleosides, irrespective the virus load at baseline.

The use of an oligonucleotide that hybridizes to DNA sequences interspersed in the genome of members of the genus Phytophthora as an adjunct to morphological criteria in species identification

An oligonucleotide (primer), designed from a conserved region of the multi-allelic b locus of the basidiomycete fungus Ustilago maydis, generated reproducible PCR fingerprints in Phytophthora species. The primer hybridized in a species-specific manner to nucleotide sequences interspersed in the genome of the closely related members of Phytophthora taxonomic group IV. We recommend the use of this PCR procedure as an alternative method for resolving the close taxonomic affinity of some members of the genus Phytophthora.

Improved body distribution of 14C-labelled AZT bound to nanoparticles in rats determined by radioluminography

The objective of the present study is to visualize differences in the body distribution between radiolabelled AZT bound to nanoparticles and a control solution. Polyhexylcyanoacrylate nanoparticles were manufactured by emulsion polymerization in the presence of AZT and an ionic emulsifier, bis(2-ethylhexyl) sulfosuccinate sodium. The AZT-control solution was equally prepared, but contained no monomer. The two preparations were administered either by i.v. injection or perorally by gavage. After determined time points the animals were sacrificed using carbon dioxide. The cadavers were shock-frozen in cellulose gel and cut into slices using a cryomicrotome. The tissue cross sections were fixed on an adhesive tape and then were freeze dried. The quantification of the radioactive AZT in the different organs and tissues was performed by radioluminography, and the images were generated on a computer. After i.v. injection of AZT-nanoparticles, a high amount of the AZT label was found in the organs belonging to the reticuloendothelial system. In these organs the radioactivity was inhomogeneously distributed showing that the uptake of the particle-associated radioactivity depended on the type of the cells located in the organs and was consistent with uptake by macrophages. The highest radioactivities were found in the GI-tract and in the liver. A difference in the elimination pathway between AZT-control solution and AZT bound to nanoparticles also was visible on the images. Similar results were obtained after oral administration. Of course, with the latter route a larger portion of AZT remained in the GI-tract especially after administration of nanoparticle-bound drug. These results confirmed those obtained by a classically performed quantitative whole body distribution study using liquid scintillation. This demonstrates that radioluminography is a useful method to study the organ distribution of drugs bound to nanoparticles.

Genetic differences between human immunodeficiency virus type 1 subpopulations in faeces and serum

To study human immunodeficiency virus type 1 (HIV-1) compartmentalization between intestine and blood, paired faecal and serum samples were collected from 204 HIV-1-infected persons. Direct sequencing of the gp120 V3 region obtained from 33 persons showed that faecal and serum sequences could be nearly homologous (0.3% different) or very dissimilar (11.3% different). Individual clones were obtained and sequenced from the faecal and serum samples of 13 persons. In 6 persons the HIV-1 subpopulations in faeces and serum were similar, whereas in 7 persons, distribution of V3 genotypes showed a marked difference. Genetic characterization of the HIV-1 subpopulations showed less heterogeneity in faecal subpopulations than in serum subpopulations in 5 of the 7 subjects. Furthermore, faecal and serum subpopulations differed predominantly by nonsynonymous nucleotide substitutions (in 6 of 7 persons). Comparison of the HIV-1 subpopulations in faeces and serum of these 7 persons, using resampling techniques, revealed a significant difference between faecal and serum subpopulations at an N-linked glycosylation site, C-terminal of the V3 loop (amino acids 331-333). Sequences from faecal subpopulations of all 7 persons contained a glycosylation site at amino acid position 331-333. Four of these 7 harboured serum variants lacking a glycosylation site at this position. The faecal subpopulations in these 4 persons showed limited nonsynonymous substitutions compared to synonymous substitutions, indicating that purifying selection is operational on these subpopulations.

Morbidity and mortality of reconstructive surgery of noninfected false aneurysms detected long after aortic prosthetic reconstruction

OBJECTIVE

To determine the morbidity and mortality of surgical treatment of false (anastomotic) aneurysms, we analyzed the results of 158 consecutive surgical procedures for repair of false aneurysms that were detected as a result of a surveillance program after aortic reconstruction with a prosthesis.

DESIGN

Retrospective analysis of patient data from a vascular registry that included information on the long-term follow-up of our patients.

SETTING

A university hospital (tertiary referral center) in the Netherlands that has been performing vascular reconstructive surgery since 1958.

PATIENTS

We performed 158 surgical procedures on 135 patients with 220 noninfected false aneurysms. Using a yearly surveillance program, the false aneurysms were detected at a mean interval of 8 years after the initial reconstruction. Most patients (60%) were asymptomatic. The operation was performed as an emergency in 25 instances (16%).

RESULTS

The mortality rate of patients receiving nonsurgical treatment was very high (61%) owing to documented rupture (11 of 18 patients). The intraoperative death rate was 7.6% per procedure. This was higher for emergency (24%) than for elective procedures (4.5%).

CONCLUSIONS

Conservative follow-up carries a very high mortality rate, as does emergency surgery for a false aneurysm. However, the intraoperative mortality rate of elective reconstruction of a false aneurysm can be in the same range as that of elective primary aortic reconstruction. Therefore, we advocate a surveillance program, including yearly ultrasound studies, after prosthetic aortic reconstruction for the timely detection and elective repair of all false aneurysms.

Classification of new phytoplasmas associated with diseases of strawberry in Florida, based on analysis of 16S rRNA and ribosomal protein gene operon sequences

Strawberry plants exhibiting symptoms of stunting and abnormally small leaves were observed in production fields in central Florida, USA. Since the symptoms were suggestive of phytoplasma infection, plants were assayed for presence of phytoplasma by PCR amplification of 16S rDNA and ribosomal protein (rp) gene sequences. Amplification of phytoplasma-specific DNA sequences by PCR indicated infection of the diseased strawberry plants by phytoplasmas. RFLP analyses of amplified 16S rDNA revealed that the plants were infected by two mutually distinct phytoplasmas that differed from strawberry green petal phytoplasma (group 16Srl-C). Both phytoplasmas were members of 16S rRNA gene group I (16Srl). Based on RFLP analysis of amplified 16S rDNA and rp gene sequences, one was classified in group 16Srl subgroup I and new rp subgroup 16Srl-l(rp); its 16S rRNA-rp subgroup was designated 16Srl-K(rr-rp). The second phytoplasma represented a previously undescribed subgroup, designated K, in 16S rRNA group I but belonged to rp subgroup 16Srl-J(rp); this phytoplasma's 16S rRNA-rp subgroup was designated 16Srl-J(rr-rp). Results of RFLP analyses agreed with putative restriction site maps based on nucleotide sequences determined for the amplified 16S rDNAs and rp gene operon DNAs. Further evidence indicated that the 16Srl-K(rr-rp) strawberry phytoplasma, Mexican periwinkle virescence phytoplasma and stolbur phytoplasma shared sequence homologies that enabled amplification of DNA from all three by PCR using primers previously designed as stolbur-specific.

Effects of antimicrobial treatment at the end of lactation on milk yield, somatic cell count, and incidence of clinical mastitis during the subsequent lactation in a dairy herd with a low prevalence of contagious mastitis

OBJECTIVE

To determine whether treating cows with antimicrobials at the end of lactation would lower the incidence of clinical mastitis, improve milk production, and decrease somatic cell count (SCC) in the subsequent lactation.

DESIGN

Randomized blind field trial.

ANIMALS

233 Holstein cows from a single herd. All cows were in lactation 2 or greater.

PROCEDURE

Cows were randomly assigned to treatment groups. Treated cows were given procaine penicillin G and novobiocin by intramammary infusion. Control cows were not treated. Farm personnel recorded cases of clinical mastitis. Milk yield and SCC were recorded during the subsequent lactation.

RESULTS

Treatment did not significantly reduce the incidence of clinical mastitis when data for all cows were grouped or when data were stratified by lactation groups (lactation 2 vs lactation > or = 3) or by last SCC (< or = 500,000 cells/ml vs > 500,000 cells/ml). Somatic cell counts (first, mean of first 5, maximum of first 5) for treated and control cows were similar, and proportions of treated and control cows with SCC > 500,000 cells/ml at least once were not significantly different. Treated cows produced 179 kg (394 lb) more milk during the first 17 weeks of lactation than did control cows.

CLINICAL IMPLICATIONS

Treating cows with antimicrobials at the end of lactation increased 17-week milk production during the subsequent lactation and, at current milk prices, was financially preferable to not treating them.

Diagnosis and therapy of aortic prosthetic fistulas: trends over a 30-year experience

A retrospective study was carried out of patients from a single institution over a 30-year period. Thirty-one patients presented with 33 fistulas, four non-enteric and 27 enteric. In 25 of 27 patients with a prosthesis-related enteric fistula gastrointestinal bleeding was present. Angiography revealed the fistula in five patients endoscopy in three, and barium studies, echography and computed tomography each revealed one fistula. Six patients died before and five died during operation. In 20 patients various techniques were used for treatment. In-hospital mortality decreased from six of eight patients before 1970, to seven of ten between 1971 and 1980, and to four of 13 after 1981. In the long term, patients treated with an extra-anatomic reconstruction had a poorer prognosis than those treated by in situ reconstruction. This experience shows that diagnostic tests often fail to reveal a prosthesis-related fistula and that mortality can be substantially reduced by early exploration in patients with negative diagnostic studies.

Serum alpha-tocopherol, vitamin A, and blood selenium concentrations, and glutathione peroxidase activity in llamas fed alfalfa hay

OBJECTIVES

To measure blood selenium concentration and glutathione peroxidase (GSH-Px) activity and serum concentrations of vitamin A and alpha-tocopherol, and to determine the correlation between blood selenium concentration and GSH-Px activity of llamas fed alfalfa hay.

DESIGN

Mean (+/- SD) serum vitamin A and alpha-tocopherol concentrations, blood selenium concentrations, and GSH-Px activity were calculated from 9 sequential blood samples collected from llamas fed a diet of alfalfa hay.

ANIMALS

15 clinically normal llamas (8 males, 7 females) between 10 and 14 months of age.

PROCEDURE

Llamas were fed alfalfa hay for 40 days prior to sample collection and then for the duration of the trial. Vitamin E, selenium, and concentrations of vitamin A precursors were measured in the hay. Blood samples were collected on days 0, 6, 7, 9, 13, 20, 42, 64, and 98. Blood selenium concentrations were measured, using an inductively coupled spectrometric method. Blood GSH-Px activity was measured with a spectrophotometer, using a modification of a previously described assay. Isocratic high-performance liquid chromatography with florescent detection was used to determine serum alpha-tocopherol and vitamin A concentrations.

RESULTS

The alfalfa hay contained 0.2 mg/kg of selenium, 5 mg/kg of vitamin E, and 0.9 mg/kg of vitamin A precursors. The mean (+/- SD) blood selenium concentration and GSH-Px activity were 0.179 +/- 0.032 micrograms/ml and 25.76 +/- 6.53 mU NADPH oxidized/min/mg of Hb, respectively, with a correlation coefficient of 0.97. The mean (+/- SD) concentrations for serum alpha-tocopherol and vitamin A were 128.1 +/- 41.7 and 74.8 +/- 5.5 micrograms/dl, respectively.

CONCLUSIONS

Blood selenium concentrations in llamas are highly correlated to GSH-Px activity. Blood selenium concentrations in llamas appear to be similar to other domestic ruminants and diets containing 0.2 mg/kg of selenium appear to provide an adequate dietary source. The concentrations of vitamin A precursors and vitamin E in the hay were below currently recommended dietary levels for llamas, and alfalfa hay appears to provide an unreliable source of vitamins A and E in this species. Further studies are required to determine optimal dietary concentrations and to substantiate a reference range for these vitamins in llamas.

Comparison of the reappearance of strongyle eggs on foals, yearlings and adult horses after treatment with ivermectin or pyrantel

The reappearance of strongyle eggs in faeces after treatment with ivermectin or pyrantel embonate was investigated in 22 foals, 36 yearlings, and 45 adult horses on five Dutch horse farms. The results confirmed earlier studies which showed an egg reappearance period of 9 and 6 weeks after ivermectin and pyrantel treatment, respectively. There were no differences between the egg reappearance periods of foals, yearlings, and adult horses. The mean egg counts of the yearlings were, however, consistently higher than the mean egg counts of the adult horses and foals in both ivermectin- and pyrantel-treated animals. It is concluded that shorter treatment intervals in foals and yearlings are not obligatory. However, longer intervals must be prevented in yearlings because their contribution to pasture contamination is relatively high.