Clinical Radiosynthesis and Translation of [18F]OP-801: A Novel Radiotracer for Imaging Reactive Microglia and Macrophages

Positron emission tomography (PET) is a powerful tool for studying neuroinflammatory diseases; however, current PET biomarkers of neuroinflammation possess significant limitations. We recently reported a promising dendrimer PET tracer ([18F]OP-801), which is selectively taken up by reactive microglia and macrophages. Here, we describe further important characterization of [18F]OP-801 in addition to optimization and validation of a two-step clinical radiosynthesis. [18F]OP-801 was found to be stable in human plasma for 90 min post incubation, and human dose estimates were calculated for 24 organs of interest; kidneys and urinary bladder wall without bladder voiding were identified as receiving the highest absorbed dose. Following optimization detailed herein, automated radiosynthesis and quality control (QC) analyses of [18F]OP-801 were performed in triplicate in suitable radiochemical yield (6.89 ± 2.23% decay corrected), specific activity (37.49 ± 15.49 GBq/mg), and radiochemical purity for clinical imaging. Importantly, imaging mice with tracer (prepared using optimized methods) 24 h following the intraperitoneal injection of liposaccharide resulted in the robust brain PET signal. Cumulatively, these data enable clinical translation of [18F]OP-801 for imaging reactive microglia and macrophages in humans. Data from three validation runs of the clinical manufacturing and QC were submitted to the Food and Drug Administration (FDA) as part of a Drug Master File (DMF). Subsequent FDA approval to proceed was obtained, and a phase 1/2 clinical trial (NCT05395624) for first-in-human imaging in healthy controls and patients with amyotrophic lateral sclerosis is underway.

Racial/ethnic differences in health-related quality of life among female breast cancer survivors: cross-sectional findings from the Medical Expenditure Panel Survey

OBJECTIVES

Breast cancer survivors have reported worse health-related quality of life (HRQoL) outcomes on some subscales when compared with members of the general population. However, the increased attention to breast cancer survivorship should have improved the HRQoL of these survivors. Our aim was to examine whether physical and mental component scores (PCS-12 and MCS-12) using the Short Form (SF-12) questionnaire were different for racial/ethnic minorities, specifically for Black and Hispanic women relative to White women. Furthermore, we stratified the data by age group to evaluate these racial/ethnic differences in HRQoL of breast cancer survivors.

STUDY DESIGN

Cross-sectional study.

METHODS

Pooled cross-sectional analyses using data from the Medical Expenditure Panel Survey between 2008 and 2016 were conducted. Pooled ordinary least squares (OLS) regression was used to examine the racial/ethnic differences in PCS-12 and MCS-12 scores of breast cancer survivors. Furthermore, stratified analyses by age group were conducted to evaluate racial/ethnic differences in HRQoL by the age of breast cancer survivors.

RESULTS

After adjusting for confounders, there was no association between race/ethnicity and PCS-12 scores. However, Hispanic breast cancer survivors had statistically significantly lower MCS-12 scores (by 1.9 points [95% confidence interval {CI}: -3.53 to -0.37]) when compared with White breast cancer survivors. For PCS-12, after stratifying by age, the adjusted analyses showed no significant differences in PCS-12 scores when White female breast cancer survivors were compared with the other racial/ethnic categories. On the other hand, Black female survivors aged <50 years had 4.3 points (95% CI: 0.46-8.13) higher MCS-12 scores when compared with their White counterparts, while Hispanic breast cancer survivors aged <50 years had 3.1 points (95% CI: -0.40-6.69) higher MCS-12 scores relative to White women. Furthermore, among female breast cancer survivors aged ≥50 years, Hispanic women had 3.2 points (95% CI: -4.98 to -1.40) lower MCS-12 scores than White women.

CONCLUSION

Our study generated findings showing the racial/ethnic differences in HRQoL of breast cancer survivors and presented results stratified by age group. These findings provide the much-needed rationale for targeted and racial/ethnic-specific HRQoL improvement strategies among breast cancer survivors.

Multiscale modelling of heterogeneous fillers in polymer composites: the case of polyisoprene and carbon black

The dispersion of inorganic particles within polymeric materials is an extensively used method to enhance their mechanical properties. One of the major challenges in the simulation of polymer composites is to model the uneven surface of the fillers which strongly affects the dynamics of the adsorbed polymers and consequently the macroscopic mechanical properties of the final composite. Here we propose a new multiscale approach that, using experimental adsorption data, constructs the filler surface to statistically reproduce the surface defects. We use this approach to analyse the structure and dynamics of highly entangled polyisoprene melt in contact with different realistic carbon black samples. We show that the presence of the heterogeneous surface has a negligible influence on the structure of the polymer chains but a major effect on their dynamics and the surface wettability.

A systematic review of cognitive behavioural therapy for anxiety in adults with intellectual disabilities

BACKGROUND

Anxiety disorders have high prevalence in people with intellectual disabilities. In populations without intellectual disabilities, cognitive behavioural therapy is a first line psychological therapy for these presentations. There is no existing review of the range of methods and outcomes from intervention studies in this area.

METHOD

A systematic review was carried out following guidance in the Cochrane handbook for systematic reviews of interventions.

RESULTS

Nineteen studies were identified. The majority of reports were descriptive case studies; the most frequently described presentations were non-specific anxiety disorders and post-traumatic stress disorder; the most frequently described cognitive techniques were psycho-education and interventions directly aimed at thoughts and beliefs and most studies reported positive outcomes, although the better controlled studies tended to report less comprehensive impacts.

CONCLUSIONS

A range of presentations have been described although the area is still at a primarily descriptive stage. We discuss intervention structures and approaches that require further research.

Rising to the challenges of achieving day surgery targets

Day surgery provides high quality and efficient care for a wide variety of surgical procedures. Patients appreciate the rapid recovery and effective analgesia, while the health service benefits from a streamlined service with lower costs. Despite the numerous advantages, day surgery practices vary enormously and many patients are still denied this excellent form of care. Fundamental to improving this situation is a change in emphasis, with day surgery becoming the default option for many surgical procedures--rather than being applied selectively--with inpatient care being used only where specifically indicated. Appropriate patient preparation is facilitated by consultant-led, nurse-run pre-assessment using modern selection criteria; only conditions which will still cause problems a few hours beyond the end of the operation should be barriers to day surgery. Pre-assessment also provides an excellent opportunity to begin patient education and ensures that pre-existing pathology is optimally treated. Efficient day surgery is best delivered by a specialised, dedicated, multi-disciplinary team, but consultant anaesthetists have a major role to play in co-ordinating policies and providing leadership. Individual anaesthetists should develop techniques that allow their patients to undergo day surgery with minimum stress, maximum comfort and the optimal chance of early discharge. Improving day surgery rates is a win-win situation, with both clinical and financial benefits.

Pharmacokinetics of anastrozole and tamoxifen alone, and in combination, during adjuvant endocrine therapy for early breast cancer in postmenopausal women: a sub-protocol of the 'Arimidex and tamoxifen alone or in combination' (ATAC) trial

The ATAC trial evaluates in a randomized, double-blind design, Arimidextrade mark (anastrozole) alone or in combination with tamoxifen, relative to tamoxifen alone as 5-year adjuvant treatment in postmenopausal women with early breast cancer. Patients included in the pharmacokinetic (PK) sub-protocol had been in ATAC for > or =3 months, taking their medication in the morning and were 100% compliant for the preceding 14 days. Blood samples were collected 24 +/- 4 h after last dose. Trough (C(min)) plasma concentrations of anastrozole, tamoxifen and desmethyltamoxifen (DMT) were measured by validated methods. The PK results were based on a total of 347 patients (131 anastrozole (1 mg o.d.), 111 tamoxifen (20 mg o.d.), 105 anastrozole and tamoxifen (1 and 20 mg o.d. respectively)). The geometric mean steady-state trough plasma concentrations of tamoxifen and DMT were statistically equivalent in patients receiving tamoxifen alone or in combination with anastrozole: geometric mean tamoxifen = 94.8 ng ml(-1)and 95.3 ng ml(-1)in tamoxifen alone and combination groups, respectively; geometric mean DMT = 265.1 and 277.6 ng ml(-1)in the tamoxifen and anastrozole and tamoxifen groups, respectively. The geometric mean anastrozole levels were 27% lower (90% Cl 20-33%;P< 0.001) in the presence of tamoxifen than with anastrozole alone. Baseline plasma oestradiol levels were not obtained in the PK sub-protocol, however, such information was available from a similar ATAC sub-protocol, which evaluated bone mineral density. Mean oestradiol levels were 21.3, 19.3, and 21.6 pmol l(-1)prior to treatment and 3.7, 20.9 and 3.6 pmol l(-1)after 3 months in the anastrozole, tamoxifen, and combination groups, respectively (n = 167). On-treatment values were below the detection limit (3 pmol l(-1)) in 43.6 and 38.5% of the anastrozole alone and anastrozole in combination with tamoxifen groups, respectively. As a result of (a) the lack of effect of anastrozole on tamoxifen and DMT levels and (b) the observed fall in blood anastrozole levels having no significant effect on oestradiol suppression by anastrozole, we conclude that the observed reduction in anastrozole levels by tamoxifen is unlikely to be of clinical significance when anastrozole and tamoxifen are administered together.

Costimulatory blockade by the induction of an endogenous xenospecific antibody response

Xenogeneic tissues induce vigorous T cell immunity, reflecting the ability of costimulatory molecules to function across species barriers. We describe a strategy to inhibit costimulation that exploits species differences using the model of porcine pancreatic islet transplantation into mice. Mice were immunized with chimeric peptides that contained a known T cell epitope and selected sequences of the porcine costimulatory molecule CD86. This resulted in anti-peptide antibody responses that recognized intact porcine CD86, blocked costimulation by porcine CD86 but not murine CD86 in vitro, and prolonged the survival of porcine islet grafts in vivo. This strategy of inducing endogenous donor-specific costimulatory blockade has potential clinical applicability.

DNA-PK-independent rejoining of DNA double-strand breaks in human cell extracts in vitro

PURPOSE

To investigate the role of DNA-dependent protein kinase (DNA-PK) in the rejoining of ionizing radiation-induced DNA double-strand breaks (dsb).

MATERIALS AND METHODS

This study employed previously described in vitro assays that utilize nuclei or 'naked' DNA prepared from agarose-embedded cells as a substrate and S-HeLa cell extracts as a source of enzymes. Rejoining of dsb in these assays is absolutely dependent on cell extract and it proceeds, under optimal reaction conditions, to an extent similar to that observed in intact cells. Results were confirmed in a plasmid-based assay for in vitro rejoining of dsb.

RESULTS

It is shown that concentrations of wortmannin completely inhibiting DNA-PK activity profoundly affect the rejoining of dsb in vivo, but have no effect on dsb rejoining in vitro. Furthermore, fractionation of cell extracts using ammonium sulphate precipitation, generates protein fractions that are able to support dsb rejoining, despite the fact that they do not contain detectable amounts of either DNA-PKcs or Ku80. Efficient rejoining of dsb in vitro is also observed with extracts of MO59J cells that lack DNA-PK activity. Finally, rejoining of dsb remains unaffected by wortmannin in a plasmid-based assay, and is also detectable with extracts of MO59J cells.

CONCLUSIONS

These findings are in contrast with genetic studies demonstrating a requirement for DNA-PK activity for efficient rejoining of dsb in vivo. The difference between in vitro and in vivo results may not be attributed to chromatin structure since wortmannin was without an effect when using nuclei as a substrate. It is speculated that the differences between in vivo and in vitro results can be explained either by assuming the operation of multiple pathways in dsb rejoining, some of which do not require DNA-PK, or by postulating a purely regulatory/damage-sensing role for DNA-PK in intact cells but no direct involvement in dsb rejoining.

Octreotide as primary therapy for acromegaly

The effects of octreotide (up to 5 yr) as primary treatment in 26 patients with acromegaly were compared with those in 81 patients with acromegaly who received octreotide as secondary or adjunctive therapy after previous surgery and/or pituitary radiation. These patients were part of a multicenter study that took place between 1989-1995. The study was divided into 3 phases beginning with a 1-month placebo-controlled treatment period followed by a 1-month washout period. In the second phase, patients were randomized to treatment with either 100 or 250 micrograms octreotide, sc, every 8 h for 6 months. Octreotide was then discontinued for 1 month and reinitiated at the lower dose for a total mean treatment duration of 39 months. The dose was titrated by each investigator to improve each patient's individual response, which included improvement in symptoms and signs of acromegaly as well as reduction of GH and insulin-like growth factor I (IGF-I) into the normal range. In the second phase of the study, in which patients were randomized to either 100 or 250 micrograms octreotide, three times daily, mean integrated GH and IGF-I concentrations after 3 and 6 months were equivalent in the primary and secondary treatment groups. During long term open label treatment, mean GH fell from 32.7 +/- 5.2 to 6.0 +/- 1.7 micrograms/L 2 h after octreotide injection in the primary therapy group and remained suppressed for a mean period of 24 months (range, 3-60 months). The mean final daily dose was 777 micrograms. In the patients receiving secondary treatment, mean GH fell from 30.2 +/- 7.6 to 5.6 +/- 1.1 micrograms/L after 3 months and remained suppressed for the remainder of the study (average dose, 635 micrograms daily). Mean IGF-I concentrations fell from 5.2 +/- 0.5 x 10(3) U/L (primary treatment group) and 4.7 +/- 0.4 x 10(3) U/L (secondary treatment group) to a mean of 2.2 +/- 0.3 x 10(3) U/L in both groups after 3 months of open label treatment and remained suppressed. IGF-I was reduced into the normal range during at least half of the study visits in 68% of the primary treatment group and in 62% of the secondary treatment group. Patients whose GH levels fell to at least 2 SD below the baseline mean GH were considered responders. There was no significant difference in the percentage of responders in the primary and secondary treatment groups (70% vs. 61%), nor was there a statistical difference in the mean GH concentrations between the groups. Symptoms of headache, increased perspiration, fatigue, and joint pain were reported at baseline by 46%, 73%, 69%, and 85%, respectively, of patients in the primary therapy group and improved during 3 yr of octreotide treatment in 50-100%. Similarly, these acromegaly-related symptoms were reported by 62%, 58%, 78%, and 60% of patients in the secondary therapy group, and improvement was noted in 62-88%. Pituitary magnetic resonance imaging scans were available in 13 of 26 patients in the primary treatment group before and after 6 months of octreotide treatment. Tumor shrinkage was observed in 6 of 13 patients, with reduction in tumor volume greater than 25% in only 3. Of 6 patients with documented tumor shrinkage, IGF-I was reduced into the normal range in 4 patients. Of the 7 remaining patients in whom tumor shrinkage was less than 10%, IGF-I was reduced into the normal range in 4 patients. Of the 7 remaining patients in whom tumor shrinkage was less than 10%, IGF-I was reduced into the normal range in 5 patients. The degree of tumor shrinkage did not correlate with the percent reduction in IGF-I or GH. In summary, octreotide was equally effective in 26 previously untreated acromegalic patients (primary treatment group) and 81 patients previously treated with either surgery or pituitary radiation (secondary treatment group). These observations call into question the current practice of surgical resection of all newly diagnosed GH-secreting pituitary adenomas regardless of the likelihood of cure. (AB

Current treatment guidelines for acromegaly

Acromegaly, an indolent disorder of growth hormone (GH) hypersecretion is most typically caused by a somatotroph cell adenoma and may be treated by several modalities. Transsphenoidal surgical resection of micro-adenomas by experienced neurosurgeons results in biochemical normalization (postglucose GH <2 ng/mL, assay-dependent, age- and sex-matched IGF-I levels) in 70% of patients. However, over 65% of GH-secreting adenomas are invasive or macroadenomas, and over 50% of these patients have persistent postoperative GH hypersecretion. Irradiation of adenomas results in attenuation of GH secretion to more than 5 ng/mL in 50% of subjects after 12 yr. However, the percent of parents who normalize IGF-I levels is less certain. Most of these patients develop associated pituitary failure and rarely develop other local adverse effects. About 60% of patients receiving somatostatin analogs achieve normalized IGF-I levels. Efficacy of medical management with somatostatin analogs may be improved by increasing injection frequency, changing delivery modes to depot preparations, and in the future, development of novel SRIF receptor subtype-specific analogs. An integrated approach to acromegaly management based upon relative risks and benefits of the currently available therapeutic modes is presented that allows for a national individualized strategy designed to achieve maximal biochemical control of GH hypersecretion and elevated IGF-I levels.

A study of bereavement in an intensive therapy unit

This study explores the experiences of relatives of patients who died in an ITU. It describes bereaved relatives' perceptions of a follow-up programme. Needs of relatives at time of death are identified. Bereaved relatives' perceptions of social support are included. Other problems present following the death of a loved one are discussed, including disposal of belongings.

Adequacy of information and acceptability of pain relief as assessed by a postpartum questionnaire

An audit cycle has been completed looking at the availability of information about different types of anaesthesia in labour, their usage and the degree of maternal satisfaction. The initial audit 7 years ago led to the production of an information leaflet on pain relief in labour. The current audit (1996) demonstrated that the majority of patients receive the leaflet and find the information useful. The leaflet may have helped improve satisfaction and selection of analgesia in primigravide. However, the leaflet needs updating to include some information on caesarean section now that this has become such a common form of delivery.

Skin tone, hostility, and blood pressure in young normotensive African Americans

Several studies have found a positive relationship between darkness of skin tone and blood pressure in African Americans. This has raised speculation about the relative contributions of genetic and/or psychosocial factors in the mediation of this relationship. Using a laboratory stress protocol, we performed cardiovascular reactivity testing with 42 male and 40 female African-American college students after pre-testing them on measures of hostility using four psychometric scales derived from the Minnesota Multiphasic Personality Inventory (MMPI). Skin tone measures were obtained with a reflectance spectrophotometer. In the combined sample of males and females, we found a weak but statistically significant positive relationship between darker skin tone and systolic blood pressure (p = 0.03). However, males were significantly darker than females (p = .005) suggesting that the skin tone and blood pressure relationship is an artifact of gender. No differences in patterns of cardiovascular habituation or levels of hostility were found between dark and light subjects. Discussion of these results focuses on the weak statistical relationship found in this and other studies and the specificity of previous findings based on educational and socioeconomic factors.

Critical care nurses' perception of a bereavement follow-up service

Over the last decade, care of patients' relatives has increasingly been seen to be of growing importance in the holistic approach to nursing care. Care of recently bereaved people has been encompassed within this and is now being seen as part of the nurses' role. Although there has been little empirical research, there is an increasing school of thought with the belief that much improvement can be achieved in the care of bereaved people in acute settings. The aim of this report is to give an insight into benefits and failings of a bereavement follow-up service within a critical care setting, as perceived by nurses.

Variants of the melanocyte-stimulating hormone receptor gene are associated with red hair and fair skin in humans

Melanin pigmentation protects the skin from the damaging effects of ultraviolet radiation (UVR). There are two types of melanin, the red phaeomelanin and the black eumelanin, both of which are present in human skin. Eumelanin is photoprotective whereas phaeomelanin, because of its potential to generate free radicals in response to UVR, may contribute to UV-induced skin damage. Individuals with red hair have a predominance of phaeomelain in hair and skin and/or a reduced ability to produce eumelanin, which may explain why they fail to tan and are at risk from UVR. In mammals the relative proportions of phaeomelanin and eumelanin are regulated by melanocyte stimulating hormone (MSH), which acts via its receptor (MC1R), on melanocytes, to increase the synthesis of eumelanin and the product of the agouti locus which antagonises this action. In mice, mutations at either the MC1R gene or agouti affect the pattern of melanogenesis resulting in changes in coat colour. We now report the presence of MC1R gene sequence variants in humans. These were found in over 80% of individuals with red hair and/or fair skin that tans poorly but in fewer than 20% of individuals with brown or black hair and in less than 4% of those who showed a good tanning response. Our findings suggest that in humans, as in other mammals, the MC1R is a control point in the regulation of pigmentation phenotype and, more importantly, that variations in this protein are associated with a poor tanning response.

TRP-1 expression correlates with eumelanogenesis in human pigment cells in culture

We have investigated the relationship in human cultured normal and malignant melanocytes between the accumulation of mRNAs encoding tyrosinase and tyrosinase-related protein-1 (TRP-1), the activity of tyrosinase and the presence of melanin. Tyrosinase mRNA correlates with tyrosinase activity and with the presence of pheomelanin, eumelanin or both melanin types. In contrast TRP-1 mRNA is only detectable in cells containing eumelanin, which suggests a role for TRP-1 in the eumelanin synthesis pathway.

Bereavement follow-up service in intensive care

Following the death of a patient nurses sometimes wonder later how the surviving relatives have coped with the death of their loved one and whether there was any further help that could have been given. This report describes services available to bereaved relatives in Intensive Care Units (ICUs) throughout the UK and how, with limited resources, a formal follow-up service to all bereaved relatives can be achieved.