Patterns of follow-up care in adult blood cancer survivors-Prospective evaluation of health-related outcomes, resource use, and quality of life

BACKGROUND

Information about follow-up care in blood cancer survivors is limited. The questionnaire-based "Aftercare in Blood Cancer Survivors" (ABC) study aimed to identify patterns of follow-up care in Germany and compare different types of follow-up institutions.

METHODS

The study's 18-month prospective part compared the follow-up institutions identified in the preceding retrospective part (academic oncologists, community oncologists, primary care physicians). The questionnaires were completed by the follow-up physicians.

RESULTS

Of 1070 physicians named by 1479 blood-cancer survivors, 478 (44.7%) consented to participate. For provision of care, most oncologists relied on published guidelines, while most primary care physicians depended on information from other physicians. Survivors with a history of allogeneic transplantation or indolent lymphoma were mainly seen by academic oncologists, whereas survivors with monoclonal gammopathy, multiple myeloma, or myeloproliferative disorders were often seen by community oncologists, and survivors with a history of aggressive lymphoma or acute leukemia by primary care physicians. Detection of relapse and secondary diseases was consistently viewed as the most important follow-up goal. Follow-up visits were most extensively documented by academic oncologists (574 of 1045 survivors cared for, 54.9%), followed by community oncologists (90/231, 39.0%) and primary care physicians (51/203, 25.1%). Relapse and secondary disease detection rates and the patients' quality of life were similar at the three institutions. Laboratory tests were most often ordered by academic oncologists, and imaging by primary care physicians. Psychosocial issues and preventive care were more often addressed by primary care physicians than by oncologists.

CONCLUSIONS

Patients at high risk of relapse or late complications were preferentially treated by academic oncologists, while patients in stable condition requiring continuous monitoring were also seen by community oncologists, and patients with curable diseases in long-term remission by primary care physicians. For the latter, transfer of follow-up care from oncologists to well-informed primary care providers appears feasible.

Emotional content reduces the cognitive effort invested in processing the credibility of social (mis)information

Emotionality likely is a key factor affecting our susceptibility to misinformation. However, the mechanisms underlying this observation are not well understood. Specifically, when people derive social information from person-related news, they rely predominantly on emotional content, apparently unperturbed by the credibility of the source. To help explain this bias, we here contrast two hypotheses of information processing reflected in changes in pupil size during news-based judgments: Emotion and cognitive effort. Thirty participants were first exposed to websites of well-known trusted or distrusted news media sources exhibiting headlines about unfamiliar persons, followed by social judgments. As expected, emotional relative to neutral headline contents lead to faster and more strongly valenced judgments. In line with the cognitive effort hypothesis, credibility modulated pupil size with larger pupils for headlines from distrusted sources, however only in response to neutral headline contents. Source credibility did not modulate pupil size in response to emotional headline contents. Instead, pupil size was smaller for emotional compared to neutral headlines for both trusted and distrusted sources. This pattern of findings suggests that emotional contents yield fluent social judgments that are made with relatively little mental effort-even if based on untrustworthy news. Cognitive resources to evaluate the credibility of news may primarily be allocated when emotional contents providing (false) fluency are not available. This insight into the biases underlying the processing of potential misinformation may be used as a protection against biased opinions and judgments. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Health-related complications during follow-up and their impact on blood cancer survivors - results from the 'Aftercare in Blood Cancer Survivors' (ABC) study

Introduction Blood cancer survivors are at increased risk for medical complications. Methods Our questionnaire-based study involved 1,551 blood cancer survivors with a ≥3-year interval since the last intense treatment. Its goal was to quantify health-related complications during follow-up and assess their impact on the patients' lives. Results 20.4% of responding survivors reported a disease relapse, most often in indolent lymphomas. Second primary malignancies occurred in 14.1%, primarily in lymphoma and allogeneic transplantation survivors. The most frequent malignancy was basal cell carcinoma of the skin, but myeloid malignancies, melanoma, bladder, head-and-neck, and thyroid cancer also appeared disproportionately frequent. An increased infection rate was reported by 43.7%, most often after allogeneic transplantation. New cardiovascular diseases were reported by 30.2%, with a high rate of thromboembolic events in multiple myeloma and myeloproliferative diseases. Polyneuropathies were reported by 39.1%, most often by survivors with a history of multiple myeloma or aggressive lymphoma. Disease relapse was perceived as the highest burden, followed by second primary malignancy, increased infection frequency, and polyneuropathy. In each area investigated, the range of perceived severities was wide. Conclusions Health-related complications are frequent during blood cancer follow-up, with significant repercussions on the patients' lives.

Impairment of vocational activities and financial problems are frequent among German blood cancer survivors

Little is known about changes in the personal living conditions of long-term blood cancer survivors in Germany. To gather information about social relationships, work life, overall well-being, and religion, we performed a questionnaire-based retrospective study on 1551 survivors who had been on follow-up for ≥ 3 years (median, 9 years). Most survivors reported that marital status and relationships with relatives and friends remained constant before and after blood cancer. Vocational activities were temporarily impaired for 47.5%, with a median time of 11 months to return to work. More than a third of the patients (35.6%) discontinued work permanently, with disability and retirement pension rates of 7.9% and 38.1%, respectively, at the time of the survey. Financial problems due to reduced income were reported by 26.2%, in particular after relapse or allogeneic transplantation. Patient reports addressing their quality of life showed large variations. It was best in acute leukemia survivors without a history of allogeneic transplantation and worst in patients with myeloproliferative disorders. Religion tended to become more important after blood cancer. In conclusion, vocational impairment and financial problems are frequent among German blood cancer survivors. Efforts should be made at an early stage to reestablish the patients' ability to work.

Preventive health care in blood cancer survivors: results from the ABC study

BACKGROUND

Blood cancer survivors are at increased risk for second primary malignancies, cardiovascular diseases, and infections. Little is known about preventive care in blood cancer survivors.

METHODS

Our questionnaire-based study included blood cancer patients diagnosed at the University Hospital of Essen before 2010, with a ≥ 3-year interval from the last intense treatment. One section of the retrospective study covered preventive care (cancer screening, cardiovascular screening, vaccination).

RESULTS

Preventive care was delivered by a general practitioner for 1100 of 1504 responding survivors (73.1%), by an oncologist for 125 (8.3%), by a general practitioner together with an oncologist for 156 (10.4%), and by other disciplines for 123 (8.2%). Cancer screening was more consistently performed by general practitioners than by oncologists. The converse was true for vaccination, with particularly high vaccination rates in allogeneic transplant recipients. Cardiovascular screening did not differ between care providers. Cancer and cardiovascular screening rates in survivors eligible for statutory prevention programs were higher than in the general population (skin cancer screening 71.1%; fecal occult blood testing 70.4%; colonoscopy 64.6%; clinical breast examination 92.1%; mammography 86.8%; cervical smear 86.0%; digital rectal examination 61.9%; blood pressure test 69.4%; urine glucose test 54.4%; blood lipid test 76.7%; information about overweight 71.0%). The Streptococcus pneumoniae vaccination rate was higher (37.0%) and the influenza vaccination rate was lower (57.0%) than in the general population.

CONCLUSIONS

Utilization of preventive care is high among German blood cancer survivors. To ensure widespread delivery and avoid redundancy, communication between oncologists and preventive care providers is essential.

Deepfake smiles matter less-the psychological and neural impact of presumed AI-generated faces

High-quality AI-generated portraits ("deepfakes") are becoming increasingly prevalent. Understanding the responses they evoke in perceivers is crucial in assessing their societal implications. Here we investigate the impact of the belief that depicted persons are real or deepfakes on psychological and neural measures of human face perception. Using EEG, we tracked participants' (N = 30) brain responses to real faces showing positive, neutral, and negative expressions, after being informed that they are either real or fake. Smiling faces marked as fake appeared less positive, as reflected in expression ratings, and induced slower evaluations. Whereas presumed real smiles elicited canonical emotion effects with differences relative to neutral faces in the P1 and N170 components (markers of early visual perception) and in the EPN component (indicative of reflexive emotional processing), presumed deepfake smiles showed none of these effects. Additionally, only smiles presumed as fake showed enhanced LPP activity compared to neutral faces, suggesting more effortful evaluation. Negative expressions induced typical emotion effects, whether considered real or fake. Our findings demonstrate a dampening effect on perceptual, emotional, and evaluative processing of presumed deepfake smiles, but not angry expressions, adding new specificity to the debate on the societal impact of AI-generated content.

Patient-reported patterns of follow-up care in the 'Aftercare in Blood Cancer Survivors' (ABC) study

BACKGROUND

Follow-up care provides long-term support for cancer survivors. Little is known about follow-up care in hematologic malignancies.

METHODS

Our questionnaire-based study included blood cancer survivors diagnosed at the University Hospital of Essen before 2010, with a ≥ 3-year interval since the last intense treatment. The primary goal of the retrospective study was the identification and characterization of follow-up institutions.

RESULTS

Of 2386 survivors meeting the inclusion criteria, 1551 (65.0%) consented to participate, with a follow-up duration > 10 years in 731. The university hospital provided care for 1045 participants (67.4%), non-university oncologists for 231 (14.9%), and non-oncological internists or general practitioners for 203 (13.1%). Seventy-two participants (4.6%) abstained from follow-up care. The disease spectrum differed among follow-up institutions (p < 0.0001). While allogeneic transplant recipients clustered at the university hospital, survivors with monoclonal gammopathy, multiple myeloma, myeloproliferative disorders, or indolent lymphomas were often seen by non-university oncologists, and survivors with a history of aggressive lymphoma or acute leukemia by non-oncological internists or general practitioners. Follow-up intervals mirrored published recommendations. Follow-up visits were dominated by conversations, physical examination, and blood tests. Imaging was more often performed outside than inside the university hospital. Satisfaction with follow-up care was high, and quality of life was similar in all follow-up institutions. A need for improvement was reported in psychosocial support and information about late effects.

CONCLUSIONS

The naturally evolved patterns identified in the study resemble published care models: Follow-up clinics for complex needs, specialist-led care for unstable disease states, and general practitioner-led care for stable conditions.

CRISPR-based oligo recombineering prioritizes apicomplexan cysteines for drug discovery

Nucleophilic amino acids are important in covalent drug development yet underutilized as anti-microbial targets. Chemoproteomic technologies have been developed to mine chemically accessible residues via their intrinsic reactivity towards electrophilic probes but cannot discern which chemically reactive sites contribute to protein function and should therefore be prioritized for drug discovery. To address this, we have developed a CRISPR-based oligo recombineering (CORe) platform to support the rapid identification, functional prioritization and rational targeting of chemically reactive sites in haploid systems. Our approach couples protein sequence and function with biological fitness of live cells. Here we profile the electrophile sensitivity of proteinogenic cysteines in the eukaryotic pathogen Toxoplasma gondii and prioritize functional sites using CORe. Electrophile-sensitive cysteines decorating the ribosome were found to be critical for parasite growth, with target-based screening identifying a parasite-selective anti-malarial lead molecule and validating the apicomplexan translation machinery as a target for ongoing covalent ligand development.

Negative news dominates fast and slow brain responses and social judgments even after source credibility evaluation

Remedies to counter the impact of misinformation are in high demand, but little is known about the neuro-cognitive consequences of untrustworthy information and how they can be mitigated. In this preregistered study, we investigated the effects of social-emotional headline contents on social judgments and brain responses and whether they can be modulated by explicit evaluations of the trustworthiness of the media source. Participants (N = 30) evaluated -and clearly discerned- the trustworthiness of news sources before they were exposed to person-related news headlines. Despite this intervention, social judgments and brain responses were dominated largely by emotional headline contents. Results suggest differential effects of source credibility might depend on headline valence. Electrophysiological indexes of fast emotional and arousal-related brain responses, as well as correlates of slow evaluative processing were enhanced for persons associated with positive headline contents from trusted sources, but not when positive headlines stemmed from distrusted sources. In contrast, negative headlines dominated fast and slow brain responses unaffected by explicit source credibility evaluations. These results provide novel insights into the brain mechanisms underlying the "success" of emotional news from untrustworthy sources, suggesting a pronounced susceptibility to negative information even from distrusted sources that is reduced for positive contents. The differential pattern of responses to misinformation in mind and brain sheds light on the cognitive mechanisms underlying the processing of misinformation and possible strategies to avoid their potentially detrimental effects.

Emotional news affects social judgments independent of perceived media credibility

How does the credibility we attribute to media sources influence our opinions and judgments derived from news? Participants read headlines about the social behavior of depicted unfamiliar persons from websites of trusted or distrusted well-known German news media. As a consequence, persons paired with negative or positive headlines were judged more negative or positive than persons associated with neutral information independent of source credibility. Likewise, electrophysiological signatures of slow and controlled evaluative brain activity revealed a dominant influence of emotional headline contents regardless of credibility. Modulations of earlier brain responses associated with arousal and reflexive emotional processing show an effect of negative news and suggest that distrusted sources may even enhance the impact of negative headlines. These findings demonstrate that though we may have distinct perceptions about the credibility of media sources, information processing and social judgments rely on the emotional content of headlines, even when they stem from sources we distrust.

Kosten der Nachsorge von Patienten mit hämatologischen Neoplasien

Zielsetzung Im Gegensatz zu hämatologischen Neoplasien im Kindesalter gibt es für Erwachsene mit diesen Erkrankungen wenige bis keine einheitlichen Nachsorgemuster und dementsprechend auch keine rational begründeten Nachsorgepläne. Des Weiteren wurden bislang keine Studien zu den mit der Nachsorge einhergehenden Kosten veröffentlicht. Die vorliegende Studie dient zur Erfassung des Ressourcenverbrauchs und der damit einhergehenden Kosten von erwachsenen Patienten.

Methodik Die Daten des Ressourcenverbrauchs wurden 2014 retrospektiv für die letzten 12 Monate mittels eines standardisierten Fragebogens erfasst. Die Krankheitskosten (direkte medizinische sowie indirekte Kosten) wurden aus der gesellschaftlichen Perspektive ermittelt. Das Jahr 2014 dient als Basisjahr für die Berechnung der Preise. Zur Ermittlung der indirekten Kosten (Erwerbsminderung, Arbeitsunfähigkeit) wurde der Friktionskostenansatz mit einer Friktionsperiode von 90 Tagen herangezogen. Weiterhin erfolgte ein Vergleich mit Hilfe des Humankapitalansatzes.

Ergebnisse Insgesamt nahmen 1531 Patienten an der gesundheitsökonomischen Erhebung teil. 89,4 % der Teilnehmer wiesen im Erfassungszeitraum mindestens einen ambulanten Arztkontakt auf. 235 Teilnehmern (15,3 %) wurde mindestens ein der Nachsorge zuzuordnendes Medikament verabreicht. 9,7 % der Studienteilnehmer gaben keinerlei Inanspruchnahme aufgrund von Nachsorge der Krebserkrankung an. Insgesamt ergaben sich direkte medizinische Kosten von durchschnittlich ca. 3627 € pro Patient. Die indirekten Krankheitskosten beliefen sich unter Verwendung des Friktionskostenansatzes auf ca. 165 € pro Patient.

Schlussfolgerung Arzneimittelkosten verursachen mit etwa 60 % den Großteil der direkten Nachsorgekosten bei Patienten mit hämatologischen Neoplasien. Nach der zugrundeliegenden Erkrankung aufgeschlüsselt weisen myeloproliferative Erkrankungen mit einem Anteil von fast 60 % die höchsten Gesamtkosten auf. Unter Verwendung des Friktionskostenansatzes lassen sich die Nachsorgekosten in 95,7 % direkte Kosten und 4,3 % indirekte Kosten unterteilen. 9,7 % der Studienteilnehmer geben keinerlei Inanspruchnahme aufgrund von Nachsorge der Krebserkrankung an und scheinen somit komplett durch das Nachsorgesystem zu fallen.

Veno-Venous Extracorporeal Membrane Oxygenation in Adult Patients with Sickle Cell Disease and Acute Chest Syndrome: a Single-Center Experience

Acute chest syndrome (ACS) in adult patients with sickle cell disease represents a leading cause of death. It is characterized by a new density on chest X-ray accompanied by fever and/or respiratory symptoms. Currently, 49 adult patients with sickle cell disease are registered at our department. By now, 12 patients (24.5%) suffered from ACS and two patients showed multiple/recurrent (>2) episodes. Death in one patient was related to acute respiratory failure secondary to ACS. In three patients with ACS, invasive mechanical ventilation and subsequent veno-venous extracorporeal membrane oxygenation (VV-ECMO) was mandatory. Veno-venous ECMO was applied within 24 hours upon arrival to the intensive care unit (ICU). All patients were treated aggressively for ACS including exchange transfusions [packed red blood cell (pRBC) units 5-16] maintaining a Hb S threshold of <30.0% in addition to broad-spectrum antibiotics, resulting in a successful outcome following decannulation from VV-ECMO (49 hours, 251 hours, 30 min., and 98 hours, respectively). Limited information is presently available on the use of VV-ECMO in adult patients with sickle cell disease in the context of acute respiratory failure secondary to ACS. The adequate timing of the decision to place ECMO in critically ill adults with sickle cell disease, incapable of being treated by conventional mechanical ventilation secondary to very severe vaso-occlusive crisis (VOC), might further reduce mortality rates while treating the underlying condition.

Fertility preservation and fulfillment of parenthood after treatment of hematological malignancies: results from the 'Aftercare in Blood Cancer Survivors' (ABC) study

Purpose

Treatment of hematological malignancies carries the risk of lasting sterility. We aimed to identify fertility-related unmet needs.

Methods

The ‘Aftercare in Blood Cancer Survivors’ study is a cohort study of hematological patients who were in treatment-free remission for ≥ 3 years or stable under continuous oral medication. Female patients age 18–45 years and male patients age 18–65 years without a history of pre-treatment infertility were asked to answer a structured questionnaire including questions addressing fertility issues. Multivariable analyses were performed to detect risk factors.

Results

Of 1562 study participants, 1031 met the inclusion criteria for the fertility sub-study. A high proportion of patients (72.4%) received information about the risk of losing fertility, but only a minority (15%) took steps to preserve it. Female and older patients were less likely to be informed. A post-treatment wish for parenthood was expressed by 19.3% of patients. It was strongly associated with childlessness at time of diagnosis and could be fulfilled by 29.4%. Fulfillment of desired parenthood increased with increasing time from diagnosis and was low after allogeneic transplantation.

Conclusions

Female and older hematological patients are less likely to be informed about fertility-related issues than other patients. With societal changes towards first parenthood at higher age, the proportion of patients desiring a child after treatment is likely to increase. Fulfillment of desired parenthood remains challenging, especially after allogeneic transplantation.

Implications for cancer survivors

In patients likely to express a wish for post-treatment parenthood, fertility-related issues should routinely be addressed before gonadotoxic treatment is started.

Electronic supplementary material

The online version of this article (10.1007/s10147-020-01639-4) contains supplementary material, which is available to authorized users.

Characterization of Miscellaneous Effluent Discharges from a Mobile Offshore Drilling Unit to the Marine Environment

A study was performed to evaluate the potential biological impacts from 8 different miscellaneous discharges from an oil and gas mobile offshore drilling unit (MODU) including deck drainage, desalination unit waste, boiler blowdown, fire control system test water, noncontact cooling water, and bilge water. Samples were evaluated for toxicity using a rapid (<1 h) initial screening test (echinoderm [Dendraster excentricus] fertilization test), and if toxicity was found, further testing was conducted using 3 chronic whole-effluent toxicity tests. This additional testing included the embryo larval development 72-h echinoderm (D. excentricus); 7-d mysid (Americamysis bahia) survival, growth, and fecundity invertebrate test; and 7-d topsmelt (Atherinops affinis) survival and growth fish test. Toxicity identification evaluations were performed on 3 discharges that consistently elicited a toxic response during whole-effluent toxicity testing. To place the results of the toxicity testing into the context of environmental risk, the spatial extent of potential biological effects was investigated using the CORMIX mixing zone model. The output of the modeling indicated that discharge of selected effluents did not result in concentrations, or duration of exposure, that would elicit toxic effects to organisms living in the surrounding environment. The present study provides a comprehensive data set that was used to characterize potential toxicity and environmental risk of MODU "miscellaneous discharges" which could help inform future risk assessments of these discharges. Environ Toxicol Chem 2019;38:2811-2823. © 2019 SETAC.

Clear judgments based on unclear evidence: Person evaluation is strongly influenced by untrustworthy gossip

Affective information about other people's social behavior may prejudice social interactions and bias person judgments. The trustworthiness of person-related information, however, can vary considerably, as in the case of gossip, rumors, lies, or "fake news." Here, we investigated how spontaneous person likability and explicit person judgments are influenced by trustworthiness, employing event-related potentials as indices of emotional brain responses. Social-emotional information about the (im)moral behavior of previously unknown persons was verbally presented as trustworthy fact (e.g., "He bullied his apprentice") or marked as untrustworthy gossip (by adding, e.g., allegedly), using verbal qualifiers that are frequently used in conversations, news, and social media to indicate the questionable trustworthiness of the information and as a precaution against wrong accusations. In Experiment 1, spontaneous likability, deliberate person judgments, and electrophysiological measures of emotional person evaluation were strongly influenced by negative information yet remarkably unaffected by the trustworthiness of the information. Experiment 2 replicated these findings and extended them to positive information. Our findings demonstrate a tendency for strong emotional evaluations and person judgments even when they are knowingly based on unclear evidence. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

ID: 34: ASSOCIATION BETWEEN VITAMIN D AND GASTRIC CANCER

Background and Objectives

Vitamin D deficiency is linked to several gastrointestinal malignancies including gastric cancer and affects a multitude of cellular processes involved in tumorigenesis. Vitamin D is presumed to have anticancer actions by inducing differentiation and cell cycle arrest in malignant cells. Furthermore, it significantly promotes apoptosis in the undifferentiated gastric cancer cell line HGC-27. The aim of this study was to determine whether there is an increased risk of gastric adenocarcinoma (GA) associated with vitamin d deficiency.

Methodology

A retrospective case-control study was conducted at Elmhurst Hospital Center from 2005–2015. Three hundred and four patients who were diagnosed with GA were selected as cases. Of 304 individuals with GA, 255 were excluded, because they did not have vitamin D levels, 49 patients were included in our study. The data was compared to a matched control group of 49 patients with no known malignancies who had vitamin D levels. Prevalence of vitamin D deficiency was compared between cases and controls using odds ratios (ORs) and 95% confidence intervals.

Results

The mean age of the case sample was 63.96 vs 60.43% in the control group. The gender distribution was the same, 49% male and 51% female. Hispanic patients were predominant in both samples accounting for 61.2% of the groups (table 1). Of 49 patients with GA included in our study, 20.48% were stage I; 36.7% were stage II; 24.9% were stage III, and 18.4% were stage IV. The prevalence of vitamin D deficiency in the case group (GA) was significantly higher than in the control group 19[38.8%] vs 7[14.3%] respectively (OR: 3.8, 95% CI 1.42–10.18, P value 0.0079) figure 1.

Conclusion

The results of our study suggest that there is a positive correlation between vitamin D deficiency and gastric adenocarcinoma. More specifically patients with vitamin D deficiency have an increased association with GA. Additional multicenter randomized double blind clinical trials are required to further assess this association and the potential benefit of vitamin D supplementation in preventing gastric adenocarcinoma.

Abstract ID: 34 Figure 1

Simultaneous early-onset immune thrombocytopenia and autoimmune thyroid disease following alemtuzumab treatment in relapsing-remitting multiple sclerosis

OBJECTIVE

We report two cases of patients with relapsing-remitting multiple sclerosis with early-onset thrombocytopenia and autoimmune thyroid disease after the first treatment course with 60-mg alemtuzumab.

METHODS

Case series and review of the literature.

RESULTS

Both patients showed severe thrombocytopenia with platelet counts of 2 × 10(9) and 11 × 10(9)/L, respectively, as well as increased thyroid antibodies within only a few months after initiating alemtuzumab treatment (11 and 9 months). Both patients responded considerably well to medical therapy including corticosteroids and intravenous immunoglobulins with slow platelet recovery over several weeks. Interestingly, both patients were previously treated with fingolimod and showed a marked lymphocytopenia that led to discontinuation.

CONCLUSION

These cases emphasize the necessity of careful clinical surveillance and proper education of patients treated with alemtuzumab as proposed by the safety-monitoring program. Previous severe lymphocytopenia under therapy with other disease-modifying therapies may be a risk factor for the development of immune thrombocytopenia.

Incremental effects of 28 days of beta-alanine supplementation on high-intensity cycling performance and blood lactate in masters female cyclists

Within the aging population, there exists a subset of individuals termed masters athletes (MA). As masters-level competition increases in popularity, MA must find methods to enhance individual athletic performance. Longitudinal beta-alanine (BA) supplementation is suggested to enhance physical capability during exercise; however, these effects have not been evaluated in MA. To examine the longitudinal effects of BA on time to exhaustion (TTE), total work completed (TWC), and lactate clearance in female MA cyclists. Twenty-two female MA (age = 53.3 ± 1.0) participated in this double-blind design. Subjects were randomly assigned to BA (n = 11; 800 mg BA + 8 g dextrose) or placebo (PLA; n = 11; 8 g dextrose) groups and supplemented 4 doses/day over 28 days. Every 7 days, subjects completed a cycling TTE at 120% VO2max, and TWC was calculated. Blood lactate was measured at baseline, immediate post, and 20-min post each TTE. No significant differences existed between groups for any variable at baseline (p > 0.05). After 28 days supplementation, BA had greater TTE (23 vs 1% change) and TWC (21 vs 2% change) than PLA (p < 0.05). Following the 20-min TTE recovery, lactate was 24% lower in BA compared to PLA (4.35 vs. 5.76 mmol/L, respectively). No differences existed for variables during intermittent weeks. 28 days of BA supplementation increased cycling performance via an enhanced time to exhaustion and total work completed with associated lactate clearance during passive rest in female MA.

Proximity-Based Non-uniform Abstractions for Approximate Planning

In a deterministic world, a planning agent can be certain of the consequences of its planned sequence of actions. Not so, however, in dynamic, stochastic domains where Markov decision processes are commonly used. Unfortunately these suffer from the `curse of dimensionality': if the state space is a Cartesian product of many small sets (`dimensions'), planning is exponential in the number of those dimensions. Our new technique exploits the intuitive strategy of selectively ignoring various dimensions in different parts of the state space. The resulting non-uniformity has strong implications, since the approximation is no longer Markovian, requiring the use of a modified planner. We also use a spatial and temporal proximity measure, which responds to continued planning as well as movement of the agent through the state space, to dynamically adapt the abstraction as planning progresses. We present qualitative and quantitative results across a range of experimental domains showing that an agent exploiting this novel approximation method successfully finds solutions to the planning problem using much less than the full state space. We assess and analyse the features of domains which our method can exploit.

Incidence and pattern of hearing impairment in children with ≤ 800 g birthweight in British Columbia, Canada

AIM

This study aimed to evaluate changes over time in the characteristics of permanent hearing impairment (HI) in extremely low-birthweight (ELBW ≤800 g) children.

METHODS

Data from sequential visits up to 5 years of age assessing hearing and other neurodevelopmental outcomes were extracted from a cohort of ELBW subjects born between 1983 and 2006 at a single Canadian site. Trends in HI incidence, severity and association with other impairments were analysed in three 8-year epochs.

RESULTS

Fifty of 586 ELBW children had a HI. HI rates increased from 5% in epoch 1 to 7% in epoch 2-13% in epoch 3 (p = 0.01). Mild HI decreased from 78% in epoch 1 to 35% in epoch 3 (p = 0.03). Median age at diagnosis decreased from 13 to 8 months. Comorbidities were more common in HI children than non-HI children: cerebral palsy (40% vs 14%, p < 0.0001)), cognitive (38% vs 12%, p < 0.0001) and visual impairments (16% vs 6%, p = 0.009).

CONCLUSION

The incidence and severity of hearing impairment in a cohort of extremely low-birthweight children increased significantly from 5% to 13% (p = 0.01) over a 24-year period. Comorbidities were common. Potentially modifiable causes are explored.

Lectin receptors of normal and dystrophic corneas

In recent years, our laboratory has used lectins to detect carbohydrate-related abnormalities in dystrophic corneas and species-specific differences in the carbohydrates of normal corneas. These studies have: 1) demonstrated that abnormal glycoconjugates are present in corneas with macular and lattice dystrophy, 2) provided additional means of differentiating corneas with macular, lattice and granular dystrophy, 3) demonstrated that distinct species-specific differences are present in the glycoconjugates of normal corneas and 4) provided guidelines for the selection of an animal model for the study of corneal glycoconjugates.

A comparison of match-only algorithms for the analysis of Plasmodium falciparum oligonucleotide arrays

This study is motivated by two data sets which employ a custom Plasmodium falciparum version of the Affymetrix GeneChip, containing only perfect match (PM) oligonucleotides. A PM-only chip cannot be analysed using the standard Affymetrix-supplied software. We compared the performance of three match-only algorithms on these data: the Match Only Integral Distribution (MOID) algorithm, Robust Multichip Analysis (RMA), and the Model Based Expression Index (MBEI). We validated the differential expression of several genes using quantitative reverse transcriptase-PCR. We also performed a comparison using two publicly available 'benchmarking' data sets: the Latin Square spike-in data set generated by Affymetrix, and the Gene Logic dilution series. Since we know what the true fold changes are in these special data sets, they are helpful for assessment of expression algorithms.

Micrococcus luteus -- survival in amber

A growing body of evidence now supports the isolation of microorganisms from ancient materials. However, questions about the stringency of extraction methods and the genetic relatedness of isolated organisms to their closest living relatives continue to challenge the authenticity of these ancient life forms. Previous studies have successfully isolated a number of spore-forming bacteria from organic and inorganic deposits of considerable age whose survival is explained by their ability to enter suspended animation for extended periods of time. However, despite a number of putative reports, the isolation of non-spore-forming bacteria and an explanation for their survival have remained enigmatic. Here we describe the isolation of non-spore-forming cocci from a 120-million-year-old block of amber, which by genetic, morphological, and biochemical analyses are identified as belonging to the bacterial species Micrococcus luteus. Although comparison of 16S rRNA sequences from the ancient isolates with their modern counterparts is unable to confirm the precise age of these bacteria, we demonstrate, using complementary molecular and cell biological techniques, evidence supporting the view that these (and related modern members of the genus) have numerous adaptations for survival in extreme, nutrient-poor environments, traits that will assist in this bacteria's persistence and dispersal in the environment. The bacteria's ability to utilize succinic acid and process terpine-related compounds, both major components of natural amber, support its survival in this oligotrophic environment.

Population genetic analysis of the Plasmodium falciparum erythrocyte binding antigen-175 (eba-175) gene

The Plasmodium falciparum erythrocyte binding antigen-175 gene (eba-175) has highly divergent allelic segments (Cseg and Fseg) in one part of the gene (region III), but only a small number of single nucleotide polymorphisms (SNPs) in the rest of the sequence. Here, evidence for the possible importance of the Cseg/Fseg dimorphism was sought in a molecular population genetic analysis of the gene. First, allele frequency distributions were determined for the Cseg/Fseg dimorphism and five SNPs in a sample of five populations in Africa. The inter-population variance in frequencies was higher for Cseg/Fseg (F(ST)=0.18) than for the SNPs (F(ST) values from 0.03 to 0.10), but these values were entirely dependent on the inclusion of one particularly divergent population (Sudan). Second, linkage disequilibrium was measured among the intragenic loci. There was the expected trend of declining linkage disequilibrium with increasing molecular distance, but it is notable that the Cseg allele was in absolute linkage disequilibrium with the two flanking SNPs, whereas the Fseg allele was associated with a broader range of SNP haplotypes. Finally, there was no association between the Cseg/Fseg alleles of eba-175 in parasites and the M/N alleles of the glycophorin A erythrocyte receptor in the human subjects.

Backbone dynamics of the natively unfolded pro-peptide of subtilisin by heteronuclear NMR relaxation studies

The dynamics of the natively unfolded form of the pro-peptide of subtilisin (PPS) have been characterized at two different pHs (6.0 and 3.0) by 15N relaxation experiments. 15N relaxation data is obtained at multiple field strengths and a detailed comparison of spectral density mapping, the model free approach and the recently proposed Cole-Cole model free (CC-MF) analysis is presented. The CC-MF analysis provides a better fit to the observed magnetic field dependence of 15N relaxation data of unfolded PPS than conventional model free approaches and shows that fluctuations in R2 may be accounted for by a distribution of correlation times on the nanosecond timescale. A new parameter epsilon derives from the analysis and represents the width of the distribution function and the heterogeneity of the dynamics on the nanosecond timescale at a particular site. Particularly interesting is the observation that epsilon is sensitive to pH changes and that PPS samples a wider distribution of nanosecond time scale motions at less acidic pHs than at more acidic pHs. These results suggest that PPS experiences a higher degree of correlated motion at pH 6.0 and that electrostatic interactions may be important for inducing correlated motions on the nanosecond timescale in unfolded PPS.

MR imaging-guided focused ultrasound surgery of fibroadenomas in the breast: a feasibility study

PURPOSE

To test the feasibility of noninvasive magnetic resonance (MR) imaging-guided focused ultrasound surgery (FUS) of benign fibroadenomas in the breast.

MATERIALS AND METHODS

Eleven fibroadenomas in nine patients under local anesthesia were treated with MR imaging-guided FUS. Based on a T2-weighted definition of target volumes, sequential sonications were delivered to treat the entire target. Temperature-sensitive phase-difference-based MR imaging was performed during each sonication to monitor focus localization and tissue temperature changes. After the procedure, T2-weighted and contrast material-enhanced T1-weighted MR imaging were performed to evaluate immediate and long-term effects.

RESULTS

Thermal imaging sequences were improved over the treatment period, with 82% (279 of 342) of the hot spots visible in the last seven treatments. The MR imager was used to measure temperature elevation (12.8 degrees -49.9 degrees C) from these treatments. Eight of the 11 lesions treated demonstrated complete or partial lack of contrast material uptake on posttherapy T1-weighted images. Three lesions showed no marked decrease of contrast material uptake. This lack of effective treatment was most likely due to a lower acoustic power and/or patient movement that caused misregistration. No adverse effects were detected, except for one case of transient edema in the pectoralis muscle 2 days after therapy.

CONCLUSION

MR imaging-guided FUS can be performed to noninvasively coagulate benign breast fibroadenomas.