Clinical Efficacy and Safety of Once-Weekly Fractionation in Stereotactic Body Radiotherapy for Pulmonary Oligometastatic Lesions

PURPOSE/OBJECTIVE(S)

As the oligometastatic disease paradigm has become more widely accepted, further investigation is needed to risk-stratify patients within this spectrum of disease and define optimal treatment methods. Stereotactic Body Radiotherapy (SBRT) has emerged as an efficacious and safe modality to control individual lesions and improve clinical outcomes in the setting of oligometastatic disease. There is scant literature describing ideal SBRT inter-fraction time intervals or their impact on clinical outcomes, especially for treating pulmonary oligometastases. Most institutions appear to offer treatments on consecutive days or every other day. In this abstract, we sought to evaluate the efficacy and safety of delivering SBRT treatments in a once-weekly fractionation scheme.

MATERIALS/METHODS

The study was undertaken via retrospective review at a single institution. We included patients with pulmonary metastatic lesions treated with SBRT at our institution between 2015 and 2019. Patients with oligometastatic disease were included, defined as patients with 5 or fewer total metastatic lesions. Treatments were delivered between 3 and 5 fractions and using at least 5 Gy per fraction. Per institutional protocol, all treatments were delivered 7 days apart.

RESULTS

From a single institution, 204 lesions from 111 patients were included. Median follow-up was 16.5 months [IQR 7 - 36.3]. Median dose was 40 Gy [IQR 30 - 50], median BED was 80 Gy [IQR 60-100], median dose per fraction was 10 Gy [IQR 8-11]. Median internal target volume (ITV) was 18.5 cc [IQR 9.3 - 45.8]. The most common tumor histologies were lung adenocarcinoma (38.2%), colorectal adenocarcinoma (15.6%), lung squamous cell carcinoma (12.7%), renal cell carcinoma (5.9%), breast invasive ductal carcinoma (5.4%), small cell lung cancer (3.9%), and melanoma (2.9%). 2-year local control (LC) rate was 85.7% and 5-year LC rate was 84.3%. 2-year regional control (RC) rate was 53.9% and 5-year RC was 49%. Median overall survival (OS) was 20 months [IQR 9 - 37.3]. Cox regression analysis revealed biologically effective dose (BED) (HR 0.99 [0.98 - 0.99] p = 0.001) as well as dose per fraction (HR 0.92 [0.86 - 0.97] p = 0.003) were both associated with improved OS. Longest tumor dimension was associated with worse OS independent of BED and dose per fraction (HR 1.26 [1.1 - 1.4] p = 0.001). Total toxicity incidence was 7.3%, which consisted only of G1-G2 cough, dyspnea, and fatigue.

CONCLUSION

Treatment of pulmonary oligometastatic lesions with SBRT delivered via once-weekly fractionation is associated with excellent local control and minimal toxicity. Larger studies are warranted to directly compare clinical outcomes of weekly SBRT fractionation to other conventional SBRT treatment schedules.

A Precision Medicine Navigator Can Mitigate Inequities Associated with Utilization of Genomic Tests in Black Men with Prostate Cancer

PURPOSE/OBJECTIVE(S)

Black men with prostate cancer in the United States experience disproportionately worse clinical outcomes compared to other racial groups. Identifying more reliable prognosticators to address these inequities has thus been the subject of considerable research scrutiny. However, prognostic genomic tools and genomic biorepositories suffer from an even greater lack of racial diversity. Strategies to mitigate these amplifying developments in inequities are desperately needed. We hypothesized that the presence of a precision medicine navigator (PMN) may mitigate inequities with standard of care (SOC) genomic test utilization among Black men with prostate cancer.

MATERIALS/METHODS

We retrospectively reviewed prostate cancer consults within one healthcare system from 11/2/2021 to 1/2/2022. We compared the frequency of patients who received SOC Decipher or Tempus genomic testing in the 7 months prior to the PMN start (pre-PMN) to the 7 months afterward (post-PMN). Chi square analysis was used to compare subgroups. Binary logistic regression was used to calculate the odds of receiving genomic testing.

RESULTS

The sample included 693 patients, 44.9% (311/693) pre-PMN and 55.1% (382/693) post-PMN, with a median age of 68 in both groups. Pre- and post-PMN racial distributions were similar with 60.1% and 60.2% White, 35.1% and 34% Black, 3.2% and 3.7% Asian/Pacific Islander, and 1.3% and 2.1% Latino, respectively. Pre- and post-PMN NCCN risk category distribution was 15.2% and 10.4% low risk, 46.8% and 49.9% intermediate risk, and 38.1% and 39.7% high risk, respectively. Pre- and post-PMN groups had 14.5% and 17% distant metastases, 77.2% and 76.9% localized disease, 10.3% and 10% prior prostatectomy, 47% and 51% income below sample median, 51% and 52% with Medicare/Medicaid, and 47% and 48% seen at community hospitals, respectively. There were no statistically significant differences for these variables pre- and post-PMN. However, from pre- to post-PMN, the proportion of Black patients receiving genomic testing increased from 19% to 58%. Black patients seen post-PMN were six times more likely to receive testing (p<0.001). Significant increases in SOC genomic testing post-PMN also occurred among lower median income patients, patients with Medicare/Medicaid, and community hospital patients.

CONCLUSION

The presence of a PMN may improve disparate rates of Black patients receiving SOC genomic tests for prostate cancer compared to other racial groups and may alleviate genomic testing inequities among other demographics.

Spacecraft sample collection and subsurface excavation of asteroid (101955) Bennu

Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging and spectral data collected during and after retrieval of a sample from Bennu’s surface. The sampling event mobilized rocks and dust into a debris plume, excavating a 9-m-long elliptical crater. This exposed material that is darker, spectrally redder, and more abundant in fine particulates than the original surface. The bulk density of the displaced subsurface material was 500–700 kg per cubic meter, about half that of the whole asteroid. Particulates that landed on instrument optics spectrally resemble aqueously altered carbonaceous meteorites. The spacecraft stored 250 ± 101 g of material, which will be delivered to Earth in 2023.

Diagnosing ventilator-associated pneumonia (VAP) in UK NHS ICUs: the perceived value and role of a novel optical technology

BACKGROUND

Diagnosing ventilator-associated pneumonia (VAP) in an intensive care unit (ICU) is a complex process. Our aim was to collect, evaluate and represent the information relating to current clinical practice for the diagnosis of VAP in UK NHS ICUs, and to explore the potential value and role of a novel diagnostic for VAP, which uses optical molecular alveoscopy to visualise the alveolar space.

METHODS

Qualitative study performing semi-structured interviews with clinical experts. Interviews were recorded, transcribed, and thematically analysed. A flow diagram of the VAP patient pathway was elicited and validated with the expert interviewees. Fourteen clinicians were interviewed from a range of UK NHS hospitals: 12 ICU consultants, 1 professor of respiratory medicine and 1 professor of critical care.

RESULTS

Five themes were identified, relating to [1] current practice for the diagnosis of VAP, [2] current clinical need in VAP diagnostics, [3] the potential value and role of the technology, [4] the barriers to adoption and [5] the evidence requirements for the technology, to help facilitate a successful adoption. These themes indicated that diagnosis of VAP is extremely difficult, as is the decision to stop antibiotic treatment. The analysis revealed that there is a clinical need for a diagnostic that provides an accurate and timely diagnosis of the causative pathogen, without the long delays associated with return of culture results, and which is not dangerous to the patient. It was determined that the technology would satisfy important aspects of this clinical need for diagnosing VAP (and pneumonia, more generally), but would require further evidence on safety and efficacy in the patient population to facilitate adoption.

CONCLUSIONS

Care pathway analysis performed in this study was deemed accurate and representative of current practice for diagnosing VAP in a UK ICU as determined by relevant clinical experts, and explored the value and role of a novel diagnostic, which uses optical technology, and could streamline the diagnostic pathway for VAP and other pneumonias.

Epidermal autophagy and beclin 1 regulator 1 and loricrin: a paradigm shift in the prognostication and stratification of the American Joint Committee on Cancer stage I melanomas

BACKGROUND

The updated American Joint Committee on Cancer (AJCC) staging criteria for melanoma remain unable to identify high-risk stage I tumour subsets.

OBJECTIVES

To determine the utility of epidermal autophagy and beclin 1 regulator 1 (AMBRA1)/loricrin (AMLo) expression as a prognostic biomarker for AJCC stage I cutaneous melanoma.

METHODS

Peritumoral AMBRA1 expression was evaluated in a retrospective discovery cohort of 76 AJCC stage I melanomas. AMLo expression was correlated with clinical outcomes up to 12 years in two independent powered, retrospective validation and qualification cohorts comprising 379 AJCC stage I melanomas.

RESULTS

Decreased AMBRA1 expression in the epidermis overlying primary melanomas in a discovery cohort of 76 AJCC stage I tumours was associated with a 7-year disease-free survival (DFS) rate of 81·5% vs. 100% survival with maintained AMBRA1 (P < 0·081). Following an immunohistochemistry protocol for semi-quantitative analysis of AMLo, analysis was undertaken in validation (n = 218) and qualification cohorts (n = 161) of AJCC stage I melanomas. Combined cohort analysis revealed a DFS rate of 98·3% in the AMLo low-risk group (n = 239) vs. 85·4% in the AMLo high-risk cohort (n = 140; P < 0·001). Subcohort multivariate analysis revealed that an AMLo hazard ratio (HR) of 4·04 [95% confidence interval (CI) 1·69-9·66; P = 0·002] is a stronger predictor of DFS than Breslow depth (HR 2·97, 95% CI 0·93-9·56; P = 0·068) in stage IB patients.

CONCLUSIONS

Loss of AMLo expression in the epidermis overlying primary AJCC stage I melanomas identifies high-risk tumour subsets independently of Breslow depth. What's already known about this topic? There is an unmet clinical need for biomarkers of early-stage melanoma. Autophagy and beclin 1 regulator 1 (AMBRA1) is a proautophagy regulatory protein with known roles in cell proliferation and differentiation, and is a known tumour suppressor. Loricrin is a marker of epidermal terminal differentiation. What does this study add? AMBRA1 has a functional role in keratinocyte/epidermal proliferation and differentiation. The combined decrease/loss of peritumoral AMBRA1 and loricrin is associated with a significantly increased risk of metastatic spread in American Joint Committee on Cancer (AJCC) stage I tumours vs. melanomas, in which peritumoral AMBRA1 and loricrin are maintained, independently of Breslow depth. What is the translational message? The integration of peritumoral epidermal AMBRA1/loricrin biomarker expression into melanoma care guidelines will facilitate more accurate, personalized risk stratification for patients with AJCC stage I melanomas, thereby facilitating stratification for appropriate follow-up and informing postdiagnostic investigations, including sentinel lymph node biopsy, ultimately resulting in improved disease outcomes and rationalization of healthcare costs.

Simulation of TTT Curves for Additively Manufactured Inconel 625

The ability to use common computational thermodynamic and kinetic tools to study the microstructure evolution in Inconel 625 (IN625) manufactured using the additive manufacturing (AM) technique of laser powder-bed fusion is evaluated. Solidification simulations indicate that laser melting and re-melting during printing produce highly segregated interdendritic regions. Precipitation simulations for different degrees of segregation show that the larger the segregation, i.e., the richer the interdendritic regions are in Nb and Mo, the faster the δ-phase (Ni₃Nb) precipitation. This is in accordance with the accelerated d precipitation observed experimentally during post-build heat treatments of AM IN625 compared to wrought IN625. The δ-phase may be undesirable since it can lead to detrimental effects on the mechanical properties. The results are presented in the form of a TTT diagram and agreement between the simulated diagram and the experimental TTT diagram demonstrate how these computational tools can be used to guide and optimize post-build treatments of AM materials.

Cost implications for the NHS of using the Alere™ i Influenza A & B near patient test with nasal swabs

BACKGROUND

Influenza is an acute viral infection of the respiratory tract. A rapid confirmatory diagnosis of influenza is important, since it is highly transmissible and outbreaks of influenza within the hospital setting increase morbidity and mortality. The objective of this study was to evaluate the cost implications, from the perspective of the UK NHS, of using on-label nasal swabs with the Alere™ i Influenza A & B test in a near patient setting.

METHODS

A cost consequence model was developed. The time horizon of the model was from hospital admission on suspicion of influenza until the end of treatment (following a diagnosis of influenza or discharge from hospital). Data on the prevalence of influenza and the sensitivity and specificity of the Alere™ i Influenza A & B test came from two prospective observational diagnostic accuracy studies. Costs were obtained from published resources. Uncertainties in the model data were investigated using deterministic, one-way sensitivity analyses.

RESULTS

Using the Alere™ i Influenza A & B point of care test with nasal swabs (on label) in NHS medical assessment units and emergency departments could save approximately £242,730 per 1000 adults presenting with influenza-like symptoms. The main cause for this was reduced times to availability of the result compared with the laboratory RT-PCR test. Other key drivers of savings were the cost of isolation, the prevalence of influenza, the specificity of the test, and the availability of isolation resources.

CONCLUSIONS

The Alere™ i Influenza A & B point of care test would have greatest impact in hospitals that have extensive delays in the time to receive a result. Sensitivity analyses identified the model parameters which would have greatest effect on the result and confirmed that assumptions were conservative, i.e. did not change key results.

Diagnostic accuracy and cost analysis of the Alere™ i Influenza A&B near-patient test using throat swabs

BACKGROUND

Clinical diagnostic sensitivity alone is inadequate in the diagnosis of influenza. Polymerase chain reaction (PCR) testing is sensitive but the inherent delays in result availability potentially prolong time to isolation and treatment. Until recently no near-patient test (NPT) has demonstrated adequate sensitivity for routine clinical use.

AIM

To evaluate diagnostic accuracy, time to result availability, clinical impact, and cost consequences of Alere™ i Influenza A&B NPT (Alere Inc., Waltham, MA, USA) using off-label throat swabs.

METHODS

Prospective, multi-centre [four UK National Health Service (NHS) hospitals], diagnostic accuracy cohort study with cost modelling. Throat swab samples from suspected influenza patients were tested for influenza using the reference standard of PCR; a second throat swab was tested using NPT.

FINDINGS

A total of 827 participants were recruited; 589 were suitable for analysis: sensitivity was 75.8% [95% confidence interval (CI): 67.0-84.6]; specificity was 96.8% (95% CI: 95.2-98.3). Sensitivity varied between Sheffield (Northern General Hospital: 82.1%; Royal Hallamshire Hospital: 83.3%) and other sites (Doncaster Royal Infirmary: 71.4%; Newcastle's Royal Victoria Infirmary: 50.0%) whereas specificity was high (92-100%). Positive predictive value (PPV) was 81.2% (95% CI: 72.9-89.5) with negative predictive value 95.6% (95% CI: 93.9-97.4) with observed prevalence of 15.4%. Median time to result for PCR was 1.1 days (on-site laboratories) and 5.2 days (remote laboratories). Isolation findings: 75% influenza positive not isolated; 69% of isolated participants did not have influenza. For a cohort of 1000 participants, annual estimated non-diagnostic cost savings with NPT are £215,040.

CONCLUSION

This first prospective study of the Alere i NPT using throat swabs demonstrates high specificity, high PPV during seasonal epidemics, and rapid result availability which could lead to substantial cost savings.

Depletion of CD4 T lymphocytes at the time of infection with M. avium subsp. paratuberculosis does not accelerate disease progression

A calf model was used to determine if the depletion of CD4 T cells prior to inoculation of Mycobacterium avium subsp. paratuberculosis (Map) would delay development of an immune response to Map and accelerate disease progression. Ileal cannulas were surgically implanted in 5 bull calves at 2 months of age. Two calves were depleted of CD4 T cells by intravenous injection of anti-bovine CD4 antibody administered 24h prior to inoculation with Map. The two CD4-depleted calves and one non-depleted calf were inoculated via ileal cannula with 1 × 10(8)cfu live Map every 3 days for a total of 4 inoculations. Two additional calves served as non-depleted and uninfected controls. Injection with the anti-CD4 mAb reduced the frequency of CD4 T cells from a pre-depletion average of 15% to less than 1% in PBMC at 24h. However, a consistent proliferative response dominated by CD4 T cells, developed in both treated and untreated calves over the course of the 6-month study period. Recovery of Map from serial biopsies obtained from the CD4-depleted and non-depleted calves after Map infection did not differ. In addition, CD4 depletion did not increase the level of Map shed in the feces over the non-depleted animal.

Dynamics of bovine spleen cell populations during the acute response to Babesia bovis infection: an immunohistological study

The spleen is a critical organ in defence against haemoparasitic diseases like babesiosis. Many in vitro and ex vivo studies have identified splenic cells working in concert to activate mechanisms required for successful resolution of infection. The techniques used in those studies, however, remove cells from the anatomical context in which cell interaction and trafficking take place. In this study, an immunohistological approach was used to monitor the splenic distribution of defined cells during the acute response of naïve calves to Babesia bovis infection. Splenomegaly was characterized by disproportionate hyperplasia of large versus small leucocytes and altered distribution of several cell types thought to be important in mounting an effective immune response. In particular, the results suggest that the initial crosstalk between NK cells and immature dendritic cells occurs within the marginal zone and that immature dendritic cells are first redirected to encounter pathogens as they enter the spleen and then mature as they process antigen and migrate to T-cell-rich areas. The results of this study are remarkably similar to those observed in a mouse model of malarial infection, suggesting these dynamic events may be central to the acute response of naïve animals to haemoparasitic infection.

Development of ultra-small-angle X-ray scattering–X-ray photon correlation spectroscopy

This paper describes the development of ultra-small-angle X-ray scattering–X-ray photon correlation spectroscopy (USAXS–XPCS). This technique takes advantage of Bonse–Hart crystal optics and is capable of probing the long-time-scale equilibrium and non-equilibrium dynamics of optically opaque materials with prominent features in a scattering vector range between those of dynamic light scattering and conventional XPCS. Instrumental parameters for optimal coherent-scattering operation are described. Two examples are offered to illustrate the applicability and capability of USAXS–XPCS. The first example concerns the equilibrium dynamics of colloidal dispersions of polystyrene microspheres in glycerol at 10, 15 and 20% volume concentrations. The temporal intensity autocorrelation analysis shows that the relaxation time of the microspheres decays monotonically as the scattering vector increases. The second example concerns the non-equilibrium dynamics of a polymer nanocomposite, for which it is demonstrated that USAXS–XPCS can reveal incipient dynamical changes not observable by other techniques.

Atomoxetine treatment in children and adolescents with ADHD and comorbid tic disorders

OBJECTIVE

To test the hypothesis that atomoxetine does not significantly worsen tic severity relative to placebo in children and adolescents with attention deficit/hyperactivity disorder (ADHD) and comorbid tic disorders.

METHODS

Study subjects were 7 to 17 years old, met Diagnostic and Statistical Manual of Mental Disorders-IV criteria for ADHD, and had concurrent Tourette syndrome or chronic motor tic disorder. Patients were randomly assigned to double-blind treatment with placebo (n = 72) or atomoxetine (0.5 to 1.5 mg/kg/day, n = 76) for up to 18 weeks.

RESULTS

Atomoxetine treatment was associated with greater reduction of tic severity at endpoint relative to placebo, approaching significance on the Yale Global Tic Severity Scale total score (-5.5 +/- 6.9 vs -3.0 +/- 8.7, p = 0.063) and Tic Symptom Self-Report total score (-4.7 +/- 6.5 vs -2.9 +/- 5.2, p = 0.095) and achieving significance on the Clinical Global Impressions (CGI) tic/neurologic severity scale score (-0.7 +/- 1.2 vs -0.1 +/- 1.0, p = 0.002). Atomoxetine patients also showed greater improvement on the ADHD Rating Scale total score (-10.9 +/- 10.9 vs -4.9 +/- 10.3, p < 0.001) and CGI severity of ADHD/psychiatric symptoms scale score (-0.8 +/- 1.1 vs -0.3 +/- 1.0, p = 0.015). Discontinuation rates were not significantly different between treatment groups. Atomoxetine patients had greater increases in heart rate and decreases of body weight, and rates of treatment-emergent decreased appetite and nausea were higher. No other clinically relevant treatment differences were seen in any other vital sign, adverse event, or electrocardiographic or laboratory measures.

CONCLUSIONS

Atomoxetine did not exacerbate tic symptoms. Rather, there was some evidence of reduction in tic severity with a significant reduction of attention deficit/hyperactivity disorder symptoms. Atomoxetine treatment appeared safe and well tolerated.

Biosecurity and biocontainment in alpaca operations

Biosecurity on South American camelid operations involves both external and internal measures to prevent the introduction and spread of disease. External biosecurity involves practices and techniques directed at the prevention of entry of new diseases into a group of animals. Internal biosecurity or biocontainment, involves practices and techniques that are directed at the prevention or spread of disease within an existing group of animals. External biosecurity is particularly important in North America camelid operations due to the extensive movement of animals for breeding or show purposes. Internal biosecurity typically involves this the prevention and treatment of failure of passive transfer, maintenance of proper nutrition and housing, and the implementation of an appropriate vaccination program for endemic or relevant diseases. Attention to appropriate cleaning and disinfection procedures related to housing, feeding, and treatment equipment is important for the maintenance of both internal and external biosecurity practices. This paper discusses various risk factors associated with the control of infectious disease in the context of external and internal biosecurity measures in camelids operations.

Rapid hematopoietic engraftment following fractionated TBI conditioning and transplantation with CD34(+) enriched hematopoietic progenitor cells from partially mismatched related donors

Nineteen adult patients with poor-risk hematologic malignancy received T cell-depleted (TCD) hematopoietic progenitor cell (HPC) transplant from partially mismatched related donors (PMRD). The preparative regimen (FITFA) included fractionated TBI, thiotepa, fludarabine, and horse (n = 3) or rabbit (n = 16) anti-thymocyte anti-sera (ATG). GVHD prophylaxis consisted of TCD by positive/negative selection using the Isolex 300i system and pre-transplant ATG with no post-transplant immunosuppression. The mean number (+/-s.d.) of transplanted CD34(+) and CD3(+) cells were 8.9 x 10(6)/kg +/-4.3 (range 2.6-19.3) and 1.4 x 10(4)/kg +/-1.2 (range 0.3-4.6) respectively. Seventeen patients evaluable for neutrophil engraftment achieved an ANC >0.5 x 10(9)/l at a median of 12 days (range 9-27), with evidence of full donor chimerism. Thirteen patients died of the following causes: relapse (n = 6), infections (n = 5), interstitial pneumonia (n = 1), and unknown causes (n = 1) None of the recipients of rabbit ATG required therapy for acute or chronic GVHD. Five patients are alive and disease-free at a median time of 303 days post transplant (range 100-660). The FITFA preparative regimen using fractionated TBI is well tolerated and is sufficiently immunosuppressive to allow rapid and stable donor origin hematopoietic engraftment without 'mega' doses of CD34(+) cells. Combination of stringent ex vivo TCD and pre-transplant ATG is effective GVHD prophylaxis.

Lack of pathogenic mutations in the 5'-untranslated region of the thrombopoietin gene in patients with non-familial essential thrombocythaemia

Thrombopoietin (TPO) is thought to be the major physiological regulator of thrombopoiesis, and, in general, circulating levels are inversely proportional to megakaryocyte and platelet mass. However, normal or elevated TPO levels are found in patients with essential thrombocythaemia (ET) and the reason for this is not fully understood. Recent studies have shown that four kindreds with hereditary thrombocythaemia (HT) have point mutations in the 5'-untranslated region (UTR) of the TPO gene which lead to increased TPO translation. In order to determine whether similar mutations are present in apparently acquired ET, in particular in those patients with polyclonal myelopoiesis, we have studied this region in 50 ET patients using neutrophil DNA. The known HT mutations were investigated using polymerase chain reaction with mismatch primers and restriction enzyme digestion; only wild-type alleles were detected. Single-stranded conformation polymorphism (SSCP) analysis of exons 1-4 identified a C-->T substitution at nucleotide 3767. However, this appears to be a common polymorphism, as it was present at the same frequency in haematologically normal controls and is unlikely to be of pathological significance. These results demonstrate that mutations in the 5' UTR of the TPO gene are not the cause of the normal or elevated TPO levels in acquired ET.

The role of ERp57 in disulfide bond formation during the assembly of major histocompatibility complex class I in a synchronized semipermeabilized cell translation system

We have established a semipermeabilized cell system that reproduces the folding and assembly of a major histocompatibility complex (MHC) class I complex as it would occur in the intact cell. The translation of the MHC class I heavy chain (HLA-B27) in this system was synchronized allowing the folding and assembly of polypeptide chains synthesized within a short time frame to be analyzed. This has enabled us to dissect the time course of interaction of both disulfide and nondisulfide-bonded heavy chain with various molecular chaperones during its assembly in a functionally intact endoplasmic reticulum. The results demonstrate that unassembled, nondisulfide-bonded forms of heavy chain interact initially with calnexin. A later and more prolonged interaction of calreticulin, specifically with assembled, disulfide-bonded heavy chain, highlights distinct differences in the roles of these two proteins in the assembly of MHC class I molecules. We also demonstrate that the thiol-dependent reductase ERp57 initially interacts with nondisulfide-bonded heavy chain, but this rapidly becomes disulfide-bonded and indicates that heavy chain folding occurs during its interaction with ERp57. In addition, we also confirm a direct interaction between MHC class I heavy chain and tapasin, emphasizing the role that this protein plays in the later stages of MHC class I assembly.

A pilot study of penicillin prophylaxis for neuropsychiatric exacerbations triggered by streptococcal infections

BACKGROUND

Some children with obsessive-compulsive disorder (OCD) and tic disorders appear to have symptom exacerbations triggered by group A beta-hemolytic streptococcal infections in a manner that is similar to rheumatic fever and its neurologic variant, Sydenham's chorea. Because penicillin prophylaxis has proven to be effective in preventing recurrences of rheumatic fever, it was postulated that it might also prevent streptococcal-triggered neuropsychiatric symptom exacerbations in children with Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS). These children are identified by five clinical characteristics: presence of OCD or tic disorder, prepubertal onset, episodic symptom course, neurologic abnormalities (i.e., choreiform movements) and streptococcal-triggered symptom exacerbations.

METHODS

Thirty-seven children with PANDAS were enrolled in an 8 month, double-blind, balanced cross-over study. Patients were randomized to receive either 4 months of the active compound (twice daily oral 250 mg penicillin V) followed by 4 months of placebo, or placebo followed by penicillin V. Tic, OCD, and other psychiatric symptoms were monitored monthly. Throat cultures and streptococcal antibody titers were also obtained.

RESULTS

There were an equal number of infections in both the active and placebo phases of the study. There was no significant change seen in either the obsessive-compulsive or tic symptom severity between the two phases.

CONCLUSIONS

Because of the failure to achieve an acceptable level of streptococcal prophylaxis, no conclusions can be drawn from this study regarding the efficacy of penicillin prophylaxis in preventing tic or OCD symptom exacerbations. Future studies should employ a more effective prophylactic agent, and include a larger sample size.

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections: clinical description of the first 50 cases

OBJECTIVE

The purpose of this study was to describe the clinical characteristics of a novel group of patients with obsessive-compulsive disorder (OCD) and tic disorders, designated as pediatric autoimmune neuropsychiatric disorders associated with streptococcal (group A beta-hemolytic streptococcal [GABHS]) infections (PANDAS).

METHOD

The authors conducted a systematic clinical evaluation of 50 children who met all of the following five working diagnostic criteria: presence of OCD and/or a tic disorder, prepubertal symptom onset, episodic course of symptom severity, association with GABHS infections, and association with neurological abnormalities.

RESULTS

The children's symptom onset was acute and dramatic, typically triggered by GABHS infections at a very early age (mean = 6.3 years, SD = 2.7, for tics; mean = 7.4 years, SD = 2.7, for OCD). The PANDAS clinical course was characterized by a relapsing-remitting symptom pattern with significant psychiatric comorbidity accompanying the exacerbations; emotional lability, separation anxiety, nighttime fears and bedtime rituals, cognitive deficits, oppositional behaviors, and motoric hyperactivity were particularly common. Symptom onset was triggered by GABHS infection for 22 (44%) of the children and by pharyngitis (no throat culture obtained) for 14 others (28%). Among the 50 children; there were 144 separate episodes of symptom exacerbation; 45 (31%) were associated with documented GABHS infection, 60 (42%) with symptoms of pharyngitis or upper respiratory infection (no throat culture obtained), and six (4%) with GABHS exposure.

CONCLUSIONS

The working diagnostic criteria appear to accurately characterize a homogeneous patient group in which symptom exacerbations are triggered by GABHS infections. The identification of such a subgroup will allow for testing of models of pathogenesis, as well as the development of novel treatment and prevention strategies.

Pharmacology of the selective serotonin reuptake inhibitors in children and adolescents

OBJECTIVE

To review the pharmacology of a new class of medications, the potent selective serotonin reuptake inhibitors (SSRIs), what is known about their metabolism in children and adolescents, and the practical clinical implications of such.

METHOD

Articles were retrieved through index Medicus searches for articles published during the past 10 years on the SSRIs and on pediatric pharmacology.

RESULTS

More than 300 articles were reviewed. Pharmacological data, derived from relevant adult literature, were summarized and extrapolated to children and from the limited pediatric literature. The SSRIs represent a new class of antidepressants with distinct advantages in their side effect profile and their broad therapeutic index over that seen with the tricyclic antidepressants. Their advantage of few anticholinergic side effects and limited cardiovascular toxicities are particularly relevant for the pediatric population. The SSRIs are metabolized via the hepatic cytochrome isoenzyme P450 system, and potential drug-drug interactions are reviewed.

CONCLUSIONS

The SSRIs appear to offer advantages over the tricyclic antidepressants. Unfortunately, pharmacokinetic data are lacking, and systematic studies of safety and efficacy in the pediatric age group are limited. Preliminary reports are encouraging, but further study is required.

A controlled trial of light therapy for the treatment of pediatric seasonal affective disorder

OBJECTIVE

To evaluate the efficacy of light therapy for the treatment of pediatric seasonal affective disorder (SAD).

METHOD

28 children (aged 7 to 17 years) at two geographically distinct sites were enrolled in a double-blind, placebo-controlled, crossover trial of bright-light treatment. Subjects initially entered a week-long baseline period during which they wore dark glasses for an hour a day. They were then randomly assigned to receive either active treatment (1 hour of bright-light therapy plus 2 hours of dawn simulation) or placebo (1 hour of clear goggles plus 5 minutes of low-intensity dawn simulation) for 1 week. The treatment phase was followed by a second dark-glasses phase lasting 1 to 2 weeks. After this phase, the children received the alternate treatment. Response was measured using the parent and child versions of the Structured Interview Guide for the Hamilton Depression Rating Scale, Seasonal Affective Disorders version (SIGH-SAD).

RESULTS

Data were analyzed as change from baseline. SIGH-SAD-P total depression scores were significantly decreased from baseline during light therapy compared with placebo (one-way analysis of variance, rho = .009), and no differences were found between the placebo and control phases. Subscores of atypical and typical depression were also significantly decreased during the active treatment (rho = .004 and .028, respectively). A similar trend was noted with the SIGH-SAD-C, but this did not reach significance. At the end of the study, 78% of the parents questioned and 80% of the children questioned rated light therapy as the phase during which the child "felt best."

CONCLUSION

Light therapy appears to be an effective treatment for pediatric SAD.

Identification of children with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections by a marker associated with rheumatic fever

OBJECTIVE

The authors' goal was to determine whether a trait marker of rheumatic fever susceptibility (labeled D8/17) could identify children with pediatric autoimmune neuropsychiatric disorders (obsessive-compulsive disorder and tic disorders) associated with streptococcal infections (PANDAS).

METHOD

Blood samples obtained from 27 children with PANDAS, nine children with Sydenham's chorea, and 24 healthy children were evaluated for D8/17 reactivity. Individuals were defined as D8/17 positive if they had 12% or more D8/17+ cells.

RESULTS

The frequency of D8/17-positive individuals was significantly higher in both patient groups than it was among the healthy volunteers: 85% of the children with PANDAS and 89% of the children with Sydenham's chorea, compared with 17% of the healthy children, were D8/17 positive. Further, the mean number of D8/17+ cells was similar in the two patient groups and was significantly higher in these groups than in the group of healthy children.

CONCLUSIONS

These results suggest that there may be a subgroup of D8/17-positive children who present with clinical symptoms of obsessive-compulsive disorder and Tourette's syndrome, rather than Sydenham's chorea, but who have similar poststreptococcal autoimmunity.

Opportunities on the Internet for child and adolescent psychopharmacologists: net access and mailing lists

The Internet, a system linking computers around the world, provides clinical and research psychopharmacologists with a convenient and efficient way to exchange information and offers a growing number of services to facilitate patient care. These opportunities are not theoretical, not in the future, and not for a select few. Many patients are already benefitting from practitioners who have sought guidance for their clinical work on the Internet. This article describes, for the novice user, how to begin the Internet journey. It also discusses psychopharmacology-related mailing lists, including a site that specializes in child and adolescent psychopharmacology. Subsequent articles will (1) show how to use Medlines to conduct literature searches and retrieve abstracts and articles from the computer screen, (2) describe ways to enter and traverse the World Wide Web (the "multimedia" portion of Internet), and (3) survey the use of "Web browsers" to find specialized psychopharmacology resources and databases, electronic journals, pertinent bulletin boards, and support services for patients and families-all with an emphasis on direct benefits to the practicing psychopharmacologist.

Sydenham's chorea: magnetic resonance imaging of the basal ganglia

Analysis of cerebral magnetic resonance images of 24 subjects with Sydenham's chorea and 48 age-, height-, weight-, gender-, and handedness-matched controls demonstrated increased sizes of the caudate, putamen, and globus pallidus in the Sydenham's chorea group. In contrast, neither total cerebral, prefrontal, or midfrontal volumes or thalamic area were increased. These results indicate the selective involvement of the basal ganglia in Sydenham's chorea.

Electrocardiographic changes during desipramine and clomipramine treatment in children and adolescents

OBJECTIVE

With the increased use of tricyclic antidepressants in children, and several reports of several sudden deaths associated with desipramine (DMI) treatment, systematic study of their cardiac effects is indicated. In the present study, DMI's and clomipramine's (CMI) short-term effects on the electrocardiogram (ECG) were compared, as well as the long-term effects of CMI.

METHOD

The ECGs of 47 children and adolescents in treatment trials were examined at baseline, after 5 weeks of CMI and of DMI treatment, and during CMI maintenance (mean duration 24.6 months).

RESULTS

At 5 weeks of CMI and of DMI treatment, the heart rate, PR, QRS, and QT-corrected (QTc) intervals on ECG were significantly increased from baseline (p < .05); DMI increased PR and QRS intervals more than CMI (p < .05), and CMI increased QTc more (p < .05). Tachycardia was the most common change (36%). More patients experienced an incomplete intraventricular conduction delay during DMI treatment (23%, 9/39) than during CMI (2%, 1/47) (p < .05). Four patients (9%) acutely developed a prolonged QTc during either DMI or CMI. Long-term maintenance ECGs during CMI treatment (n = 25) were not significantly different from that at week 5, although some individuals developed or resolved specific ECG changes.

CONCLUSION

CMI and DMI both produced ECG changes typically reported for tricyclic antidepressants, and they differed on specific ECG changes. Changes in ECG measures for individuals from short to long term suggest that continued monitoring is required.

Current knowledge of medications for the treatment of childhood anxiety disorders

OBJECTIVE

This report will review the costs, risks, and benefits of potentially useful medications for the treatment of children and adolescents with anxiety disorders and will identify areas where data are limited and additional research is needed.

METHOD

A Medline-assisted review of the literature was performed. Attention was given to dosage, response, and side effects of medications. Wherever possible, blinded, controlled medication trials in children with anxiety disorders (diagnosed by structured criteria) were targeted for use as the primary references. Relatively few systematic studies were found, so information from open trials and case reports also was included, as were controlled trials in adult populations.

RESULTS

The largest body of work supporting the use of medications for childhood anxiety came from studies of obsessive-compulsive disorder, where clomipramine and fluoxetine have been found effective in systematic studies. In other childhood anxiety disorders, there are conflicting data about the efficacy of medications, such as tricyclic antidepressants, benzodiazepines, serotonin reuptake inhibitors, beta-blockers, and monoamine oxidase inhibitors.

CONCLUSIONS

This review of the systematic pharmacological trials for childhood anxiety disorders revealed only 13 controlled studies: 5 for obsessive-compulsive disorder, 4 for school refusal/separation anxiety disorder, and 4 for avoidant/overanxious disorder or mixed diagnostic groups. Medications appear to be helpful for childhood anxiety disorders, although definitive pharmacotherapeutic data are lacking for many conditions. A systematic study of these medications is required to establish safety and efficacy in the pediatric age group. Evolving diagnostic criteria and terminology, the presence of comorbid diagnoses (especially affective disorders), and inadequate medication dosages may be factors hindering research in this field. Until additional research is done, clinicians must carefully consider the relative risk-to-benefit ratio when prescribing these medications.

Rates of seasonal affective disorder in children and adolescents

OBJECTIVE

The authors estimated the frequency of seasonal affective disorder in children and adolescents and examined the relationship of this rate to age and pubertal status.

METHOD

A modified version of the Seasonal Pattern Assessment Questionnaire was distributed to 2,267 students at a middle school and a high school in a suburb of Washington, D.C. A case diagnosis was made if the respondent scored over 18 and also indicated that the change of seasons was at least a "pretty bad" problem.

RESULTS

A total of 1,871 questionnaires (82.5%) were returned. Sixty probable cases of seasonal affective disorder (3.3%) were identified among the 1,835 surveys analyzed. Age was directly correlated with the frequency of seasonal affective disorder, and the rate was higher in postpubertal girls. Differences between the subjects with and without identified cases of seasonal affective disorder were seen in the symptom endorsement patterns, particularly for "feel worst," "least energy," "most irritable," and "socialize least."

CONCLUSIONS

These pilot data suggest that between 1.7% and 5.5% of 9-19-year-old children may have seasonal affective disorder. Further research is warranted, particularly that which examines the relationship between seasonal affective disorder and puberty.

The translocation, folding, assembly and redox-dependent degradation of secretory and membrane proteins in semi-permeabilized mammalian cells

We describe here a semi-permeabilized cell-system which reconstitutes the efficient synthesis, translocation, folding, assembly and degradation of membrane and secretory proteins. Cells grown in culture were treated with the detergent digitonin which selectively permeabilized the plasma membrane leaving the cellular organelles, such as the endoplasmic reticulum (ER) and trans-Golgi network intact. These permeabilized cells were added to an in vitro translation system, either wheatgerm or reticulocyte lysate, supplemented with RNA coding for either membrane or secretory proteins. Efficient translocation and modification of proteins by these cells was demonstrated by protease protection, photocross-linking of nascent chains to components of the translocation apparatus and by post-translational modifications such as glycosylation or hydroxylation. A comparison was made between the ability of semi-permeabilized cells and microsomal vesicles to fold and assemble proteins. The results show that the intact ER within these cells can assemble proteins much more efficiently than vesicularized ER. Furthermore, the semi-permeabilized cells carried out the redox-dependent degradation of tissue-type plasminogen activator. This system has all the advantages of conventional cell-free systems, including speed and, importantly, the ability to manipulate the components of the assay, while retaining intracellular organelles and, therefore, allowing cellular processes to occur as they would in the intact cell.

Bupropion versus methylphenidate in the treatment of attention-deficit hyperactivity disorder

OBJECTIVE

In the treatment of attention-deficit hyperactivity disorder (ADHD), the efficacy of the tricyclic antidepressants and monoamine oxidase inhibitor antidepressants has been compared with that of both placebo and the stimulants (methylphenidate and/or dextroamphetamine). However, the effectiveness of bupropion has been contrasted only with placebo. The primary aim of this study was to contrast the efficacy of bupropion with that of methylphenidate in the treatment of ADHD.

METHOD

A double-blind, crossover design was used in this study. After a 14-day medication washout period, 15 ADHD subjects (7 to 17 years old) were randomized to either methylphenidate or bupropion for 6 weeks, washed out for an additional 2 weeks, and then "crossed over" to the other drug. Methylphenidate was titrated to the maximum effective dose of 0.4 to 1.3 mg/kg per day (mean 0.7 mg/kg per day) and bupropion was titrated to an effective dose ranging from 1.4 to 5.7 mg/kg per day (mean 3.3 mg/kg per day).

RESULTS

Both methylphenidate and bupropion produced significantly greater (p < .001) and equivalent improvement on the Iowa-Conners Teacher's Rating Scale according to both the subjects' parents and teachers. The same pattern of improvement was also noted for improvement on the Clinical Global Impression Scale, Kagan's Matching Familiar Figures Test, Continuous Performance Test, Children's Depression Inventory, Children's Manifest Anxiety Scale, and Rey Auditory-Verbal Learning Test.

CONCLUSIONS

In this double-blind, crossover trial, bupropion and methylphenidate were both effective and did not differ in their overall efficacy as treatments for ADHD.

Case study: a new infection-triggered, autoimmune subtype of pediatric OCD and Tourette's syndrome

A review of clinical observations and literature reports leads to the hypothesis that, via a process analogous to Sydenham's chorea, infections with group A beta-hemolytic streptococci, among others, may trigger autoimmune responses that cause or exacerbate some cases of childhood-onset obsessive-compulsive disorder (OCD) or tic disorders (including Tourette's syndrome). If this hypothesis is correct, then immunological treatments should lead to decreased symptoms in some cases. Four cases with abrupt, severe onset or worsening of OCD or tics are presented from an open treatment study. All were boys aged 10 to 14 years. One had OCD, one had Tourette's syndrome, and two had both OCD and Tourette's syndrome. Clinically and on standardized rating scales, their symptoms were in the moderate to very severe range. Two had evidence of recent group A beta-hemolytic streptococci infections, and the others had histories of recent viral illnesses. Two were treated with plasmapheresis, one with intravenous immunoglobulin, and one with immunosuppressive doses of prednisone. All had a clinically significant response immediately after treatment. Diagnostic criteria are provided that describe these cases of pediatric, infection-triggered, autoimmune neuropsychiatric disorders (PITANDs). Suggestions are made regarding the evaluation and management of patients who may have this condition.

The effect of the shape function on small-angle scattering analysis by the maximum-entropy method

Analysis of small-angle scattering data to obtain a particle-size distribution is dependent upon the shape function used to model the scattering. From a maximum-entropy analysis of small-angle scattering data, the effect of shape-function selection on the obtained size distribution is demonstrated using three different shape functions to describe the same scattering data from each of two alloys. The alloys have been revealed by electron microscopy to contain a distribution of randomly oriented and mainly noninteracting irregular ellipsoidal precipitates. A comparison is made between the different forms of the shape function. The effect of an incident-wavelength distribution is also shown. The importance of testing appropriate shape functions and validating these against other microstructural studies is discussed.

Clonazepam as an augmenting agent in the treatment of childhood-onset obsessive-compulsive disorder

This case study is of a young man with childhood onset of severe obsessive-compulsive disorder (OCD). The patient had no clinical improvement during therapeutic trials of clomipramine, fluoxetine, and fluvoxamine, including buspirone augmentation. The patient consumed 50 tablets of fluoxetine in a suicide attempt and experienced a total remission of his OCD symptoms for the first time in his life. This remission lasted approximately 1 month and raises interesting questions about the mechanism of action of the serotonin reuptake inhibitors. Subsequently, the patient was able to achieve a 75% improvement in symptomatology when treated with a combination of fluoxetine and clonazepam. This open report suggests that clonazepam may be an effective augmentation agent to a serotonin reuptake inhibitor in the treatment of OCD.

Dose-dependent, K+-stimulated efflux of endogenous taurine from primary astrocyte cultures is Ca2+-dependent

The K+-stimulated efflux of endogenous taurine from primary rat cerebellar astrocyte cultures prepared from 7-9-day-old rats was studied at 16-18 days in vitro using HPLC analysis. Taurine efflux was dose-dependent at K+ concentrations between 10 mM and 80 mM, with an EC50 of approximately 50 mM. Maximum stimulation of efflux above basal levels ranged from 56% at 10 mM K+ (204 pmol/min/mg protein) to 470% at 80 mM K+ (960 pmol/min/mg protein). Removal of Ca2+ from the buffer and the addition of either 1 mM EGTA or 10 mM Mg2+ abolished K+-stimulated efflux. Taurine efflux peaked and fell in parallel with the K+ concentration, but with an approximate lag of 3-5 min. The time course and amount of preloaded [3H]taurine released did not differ significantly from that seen for endogenous efflux. Basal taurine efflux varied inversely with the extracellular concentration of Ca2+ over the concentration range 0-5.0 mM. The observed Ca2+ dependence is consistent with a role for Ca2+ in the regulation of taurine release. Furthermore, taurine release from astrocytes in response to elevated K+ may reflect a neuromodulatory role for this amino acid in the CNS.

HPLC analysis of putative amino acid neurotransmitters released from primary cerebellar cultures

An HPLC method is described that measures amino acids (putative neurotransmitters and/or neuromodulators) released from primary, dissociated cerebellar cells maintained in monolayer culture. Precolumn derivatization with phenylisothiocyanate, followed by reverse phase chromatography with UV detection was used to quantitate the phenylcarbamyl amino acid derivatives in a chemically defined medium. Quantitation was linear, reproducible and sensitive to one picomole. This method is useful for the measurement of putative neurotransmitters GABA, glutamate, aspartate, taurine and adenosine, and can easily be modified to analyze other amino acids in physiological samples.