Biophysical characterization of human-cell-expressed, full-length κI O18/O8, AL-09, λ6a, and Wil immunoglobulin light chains

Immunoglobulin light chain (AL) amyloidosis involves the deposition of insoluble monoclonal AL protein fibrils in the extracellular space of different organs leading to dysfunction and death. Development of methods to efficiently express and purify AL proteins with acceptable standards of homogeneity and structural integrity has become critical to understand the in vitro and in vivo aspects of AL protein aggregation, and thus the disease progression. In this study, we report the biophysical characterization of His-tagged and untagged versions of AL full-length (FL) κI and λ6 subgroup proteins and their mutants expressed from the Expi293F human cell line. We used an array of biophysical and biochemical methods to analyze the structure and stability of the monomers, oligomerization states, and thermodynamic characteristics of the purified FL proteins and how they compare with the bacterially expressed FL proteins. Our results demonstrate that the tagged and untagged versions of FL proteins have comparable stability to proteins expressed in bacterial cells but exhibit multiple unfolding transitions and reversibility. Non-reducing SDS-PAGE and analytical ultracentrifugation analysis showed presence of monomers and dimers, with an insignificant amount of higher-order oligomers, in the purified fraction of all proteins. Overall, the FL proteins were expressed with sufficient yields for biophysical studies and can replace bacterial expression systems.

Left ventricular diastolic function in patients with breast cancer treated with anthracycline-based chemotherapy

Background

Despite major progress in novel breast cancer therapeutic regimens, anthracycline-based chemotherapy (ANT) remains among the most effective therapies. Cardiotoxicity, one of the most severe adverse events of ANT, has been defined as a reduction in left ventricular ejection fraction (LVEF) or global longitudinal strain (GLS). However, the role of early diastolic dysfunction has been insufficiently researched. We aimed to determine if diastolic dysfunction could early diagnose and predict ANT cardiotoxicity.

Methods

Studies that reported on echocardiographic parameters of diastolic function before and at the end of ANT in breast cancer patients without cardiac disease were included. We evaluated parameter derived from pulsed wave Doppler interrogation of the mitral valve inflow (E/A ratio and mitral E-wave deceleration time (EDT)) and tissue Doppler (mean velocities of the mitral ring in the early diastole (E') and E/E' ratio).

Results

A total of 892 patients from 13 studies were included. E/A ratio was significantly reduced at the end of ANT (OR 2.34, 95% CI [1.49, 3.68], p<0.001), while EDT was not significantly influenced (OR 0.74, 95% CI [0.50, 1.08], p=0.121). Tissue Doppler velocity of the mitral ring E' and the LV filling pressure analysed through E/E' ratio did not show significant changes after ANT (OR 2.32, 95% CI [0.94, 5.72], p=0.068, and OR 0.79, 95% CI [0.56, 1.12], p=0.197, respectively). A modest reduction in LVEF and global longitudinal strain (GLS) was observed at the end of the ANT therapy with a difference in means of 3.77% and −1.08%, respectively. Patients receiving ANT doses over 400 mg/m2 doxorubicin or epirubicin therapeutic equivalent doses showed a significant change in E/A and E' after the therapy. Cardioprotective therapy like carvedilol, nebivolol and spironolactone did not have a significant impact on the parameter of diastolic function.

Conclusion

ANT has a modest early impact on LV diastolic function in patients with breast cancer without cardiac disease and cannot be validated as an early diagnostic or prognostic tool of ANT-induced cardiotoxicity. Randomized studies on larger population, using new parameter e.g. left atrial function parameter and multimodality imaging are required.

Funding Acknowledgement

Type of funding sources: None.

Left ventricular global longitudinal strain reduction in patients with melanoma and extra-cardiac immune-related adverse events during immune checkpoint inhibitor therapy

Background

Immune checkpoint inhibitors (ICI) have tremendously improved survival in patients with melanoma. By unbalancing the immune system, ICI also generate immune-related adverse events (IRAEs) that could affect any tissue, including the heart. Early detection of IRAEs is essential to avoid life-threatening adverse events like myocarditis and to maintain patients under this effective therapy.

Aim

To identify whether patients treated with ICI that develop extra-cardiac IRAEs additionally show a subclinical impairment of the heart function.

Methods

We have analysed the patients with melanoma without established cardiac disease evaluated in our cardio-oncology unit between July 2018 and December 2019. Data was collected at two timepoints: before initiating the ICI therapy (baseline) and one month after ICI treatment begin (follow-up). Evaluation was performed using clinical data, laboratory parameter including biomarkers, electrocardiography, comprehensive 2D, 3D, tissue Doppler, and speckle tracking echocardiography assessment, and cardiac magnetic imaging.

Results

A total of 69 patients with melanoma (59±12 years old, 63% males, 93.8% metastatic disease), without known cardiovascular disease were included. Patients were divided in two groups: patients with extra-cardiac IRAEs (Group 1, n=22) and without IRAEs (Group 2, n=46) after one month of ICI therapy. One patient was diagnosed with immune-related myocarditis at follow-up and was excluded from the analysis. Patients in Group 1 developed colitis (n=10), thyroiditis/hypophysitis (n=8), hepatitis (n=2), and pneumonitis (n=2). There were no differences in age, gender distribution, cardiovascular risk factors, or proportion of metastatic disease between the two groups. The proportion of patients treated with combination ICI therapy (nivolumab plus ipilimumab) was significantly higher in Group 1 (72% vs. 33%, p=0.04). The left ventricular systolic and diastolic function were similar at baseline and after one month of therapy between the two groups, except for the global longitudinal strain (GLS), which showed a significant reduction at follow-up for patients in Group 1 vs. Group 2 (−18.8±2.6% vs. −21±1.2%, p=0.03). The radial and circumferential strain were similar. Follow-up GLS had a good correlation with the extra-cardiac IRAEs rate (r=0.43; p=0.03). Patients with combination ICI therapy had a 5 times higher risk to develop extra-cardiac IRAEs (OR 5.33, 95% CI (1.07–26.61), p=0.04). Troponin and NT-proBNP were not significantly different at follow-up between the two groups.

Conclusion

The abnormal function of the immune system triggered by ICI therapy in patients with extra-cardiac IRAEs seems to induce a subclinical left ventricular dysfunction, signalized by a reduction of the GLS. However, the diagnosis criteria for myocarditis were fulfilled in only one patient. The mechanism of these changes should be further investigated and addressed.

Funding Acknowledgement

Type of funding source: None

The age-dependent relationship between resting heart rate variability and functional brain connectivity

Resting heart rate variability (HRV), an index of parasympathetic cardioregulation and an individual trait marker related to mental and physical health, decreases with age. Previous studies have associated resting HRV with structural and functional properties of the brain - mainly in cortical midline and limbic structures. We hypothesized that aging affects the relationship between resting HRV and brain structure and function. In 388 healthy subjects of three age groups (140 younger: 26.0 ± 4.2 years, 119 middle-aged: 46.3 ± 6.2 years, 129 older: 66.9 ± 4.7 years), gray matter volume (GMV, voxel-based morphometry) and resting state functional connectivity (eigenvector centrality mapping and exploratory seed-based functional connectivity) were related to resting HRV, measured as the root mean square of successive differences (RMSSD). Confirming previous findings, resting HRV decreased with age. For HRV-related GMV, there were no statistically significant differences between the age groups, nor similarities across all age groups. In whole-brain functional connectivity analyses, we found an age-dependent association between resting HRV and eigenvector centrality in the bilateral ventromedial prefrontal cortex (vmPFC), driven by the younger adults. Across all age groups, HRV was positively correlated with network centrality in the bilateral posterior cingulate cortex. Seed-based functional connectivity analysis using the vmPFC cluster revealed an HRV-related cortico-cerebellar network in younger but not in middle-aged or older adults. Our results indicate that the decrease of HRV with age is accompanied by changes in functional connectivity along the cortical midline. This extends our knowledge of brain-body interactions and their changes over the lifespan.

First Evidence For Glial Pathology In Late Life Minor Depression: s100b Is Increased In Males With Minor Depression

Minor depression is diagnosed when a patient suffers from two to four depressive symptoms for at least two weeks. Though minor depression is a widespread phenomenon, its pathophysiology has hardly been studied. To get a first insight into the pathophysiological mechanisms underlying this disorder we assessed serum levels of biomarkers for plasticity, glial and neuronal function: brain-derived neurotrophic factor (BDNF), S100B and neuron specific enolase (NSE). Twenty-seven subjects with minor depressive episode and 82 healthy subjects over 60 years of age were selected from the database of the Leipzig population-based study of civilization diseases (LIFE). Serum levels of BDNF, S100B and NSE were compared between groups, and correlated with age, body-mass index, and degree of white matter hyperintensities (score on Fazekas scale). S100B was significantly increased in males with minor depression in comparison to healthy males, whereas other biomarkers did not differ between groups (P = 0.10–0.66). NSE correlated with Fazekas score in patients with minor depression (rs = 0.436, P = 0.048) and in the whole sample (rs = 0.252, P = 0.019). S100B correlated with body mass index (rs = 0.246, P = 0.031) and with age in healthy subjects (rs = 0.345, P = 0.002). Increased S100B in males with minor depression, without alterations in BDNF and NSE, supports the glial hypothesis of depression. Correlation between white matter hyperintensities and NSE underscores the vascular hypothesis of late life depression.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Getting depression clinical practice guidelines right: time for change?

OBJECTIVE

As part of a series of papers ['Chronobiology of mood disorders' Malhi & Kuiper. Acta Psychiatr Scand 2013;128(Suppl. 444):2-15; and 'It's time we managed depression: The emerging role of chronobiology' Malhi et al. Acta Psychiatr Scand 2013;128(Suppl. 444):1] examining chronobiology in the context of depression, this article examines recent western clinical practice guidelines (CPGs) for the treatment of depression with respect to the recommendations they make, in particular as regards chronobiological treatments, and briefly considers the implications of their methodology and approach.

METHOD

Five international treatment guidelines, which had been published in the past 5 years, were identified, representing North American and European views. Chosen guidelines were reviewed by the authors, and the relevant recommendations were distributed for discussion and subsequent synthesis.

RESULTS

Most current guidelines do not address chronobiology in detail. Chronotherapeutic recommendations are tentative, although agomelatine is considered as an option for major depression and bright light therapy for seasonal affective disorder. Sleep deprivation is not routinely recommended.

CONCLUSION

Recommendations are limited by the lack of reliable therapeutic markers for chronotherapeutics. Current evidence supports use of light therapy in seasonal depression, but in non-seasonal depression there is insufficient evidence to support reliance on chronotherapeutics over existing treatment modalities.

Psychological management of unipolar depression

OBJECTIVE

To be used in conjunction with 'Pharmacological management of unipolar depression' [Malhi et al. Acta Psychiatr Scand 2013;127(Suppl. 443):6-23] and 'Lifestyle management of unipolar depression' [Berk et al. Acta Psychiatr Scand 2013;127(Suppl. 443):38-54]. To provide clinically relevant recommendations for the use of psychological treatments in depression derived from a literature review.

METHOD

Medical databases including MEDLINE and PubMed were searched for pertinent literature, with an emphasis on recent publications.

RESULTS

Structured psychological treatments such as cognitive behaviour therapy and interpersonal therapy (IPT) have a robust evidence base for efficacy in treating depression, even in severe cases of depression. However, they may not offer benefit as quickly as antidepressants, and maximal efficacy requires well-trained and experienced therapists. These therapies are effective across the lifespan and may be preferred where it is desired to avoid pharmacotherapy. In some instances, combination with pharmacotherapy may enhance outcome. Psychological therapy may have more enduring protective effects than medication and be effective in relapse prevention. Newer structured psychological therapies such as mindfulness-based cognitive therapy and acceptance and commitment therapy lack an extensive outcome literature, but the few published studies yielding positive outcomes suggest they should be considered options for treatment.

CONCLUSION

Cognitive behaviour therapy and IPT can be effective in alleviating acute depression for all levels of severity and in maintaining improvement. Psychological treatments for depression have demonstrated efficacy across the lifespan and may present a preferred treatment option in some groups, for example, children and adolescents and women who are pregnant or postnatal.

Clinical practice recommendations for bipolar disorder

OBJECTIVE

To provide clinically relevant evidence-based recommendations for the management of bipolar disorder in adults that are informative, easy to assimilate and facilitate clinical decision-making.

METHOD

A comprehensive literature review of over 500 articles was undertaken using electronic database search engines (e.g. MEDLINE, PsychINFO and Cochrane reviews). In addition articles, book chapters and other literature known to the authors were reviewed. The findings were then formulated into a set of recommendations that were developed by a multidisciplinary team of clinicians who routinely deal with mood disorders. These preliminary recommendations underwent extensive consultative review by a broader advisory panel that included experts in the field, clinical staff and patient representatives.

RESULTS

The clinical practice recommendations for bipolar disorder (bipolar CPR) summarise evidence-based treatments and provide a synopsis of recommendations relating to each phase of the illness. They are designed for clinical use and have therefore been presented succinctly in an innovative and engaging manner that is clear and informative.

CONCLUSION

These up-to-date recommendations provide an evidence-based framework that incorporates clinical wisdom and consideration of individual factors in the management of bipolar disorder. Further, the novel style and practical approach should promote their uptake and implementation.

Clinical practice recommendations for depression

OBJECTIVE

To provide clinically relevant evidence-based recommendations for the management of depression in adults that are informative, easy to assimilate and facilitate clinical decision making.

METHOD

A comprehensive literature review of over 500 articles was undertaken using electronic database search engines (e.g. MEDLINE, PsychINFO and Cochrane reviews). In addition articles, book chapters and other literature known to the authors were reviewed. The findings were then formulated into a set of recommendations that were developed by a multidisciplinary team of clinicians who routinely deal with mood disorders. The recommendations then underwent consultative review by a broader advisory panel that included experts in the field, clinical staff and patient representatives.

RESULTS

The clinical practice recommendations for depression (Depression CPR) summarize evidence-based treatments and provide a synopsis of recommendations relating to each phase of the illness. They are designed for clinical use and have therefore been presented succinctly in an innovative and engaging manner that is clear and informative.

CONCLUSION

These up-to-date recommendations provide an evidence-based framework that incorporates clinical wisdom and consideration of individual factors in the management of depression. Further, the novel style and practical approach should promote uptake and implementation.

[Relevance of a performance capacity model for uniform and standardized performance diagnostics]

To obtain a standardized method for performance capacity assessment in social medicine reference to a generally accepted model of performance capacity is necessary. Further, such a model enables description of the effects of chronic disease on performance capacity. This article describes how the term "performance capacity" can be reduced to operational basal parameters by a hierarchic breakdown, with the domain "physical performance capacity" having the most complex structure. Furthermore the construction of a graduation according to work-load taxonomies for every parameter is shown. The collection of data on the level of basal parameters is essential to assess the concrete performance capacity. To apply the model as a basis for estimating the effects of chronic disease, graduated disease features have to be created. The benefit of the procedure described lies in increased transparency of the decision process. Hence, performance capacity assessment will gain reliability and objectivity.

Social phobia in the Australian National Survey of Mental Health and Well-Being (NSMHWB)

BACKGROUND

This article reports data on social phobia from the first large scale Australian epidemiological study. Prevalence rates, demographic correlates and co-morbidity in the sample that met criteria for social phobia are reported and gender differences examined.

METHOD

Data were obtained from a stratified sample of 10641 participants as part of the Australian National Survey of Mental Health and Well-Being (NSMHWB). A modified version of the Composite International Diagnostic Interview (CIDI) was used to determine the presence of social phobia, as well as other DSM-IV anxiety, affective and substance use disorders. The interview also screened for the presence of nine ICD-10 personality disorders, including anxious personality disorder, the equivalent of DSM-IV avoidant personality disorder (APD).

RESULTS

The estimated 12 month prevalence of social phobia was 2.3%, lower than rates reported in several recent nationally representative epidemiological surveys and closer to those reported in the Epidemiological Catchment Area study (ECA) and other DSM-III studies. Considerable co-morbidity was identified. Data indicated that the co-morbidity with depression and alcohol abuse and dependence were generally subsequent to onset of social phobia and that the additional diagnosis of APD was associated with a greater burden of affective disorder. Social phobia most often preceded major depression, alcohol abuse and generalized anxiety disorder.

CONCLUSIONS

Social phobia is a highly prevalent, highly co-morbid disorder in the Australian community. Individuals with social phobia who also screen positively for APD appear to be at greater risk of co-morbidity with all surveyed disorders except alcohol abuse or dependence.

[The diagnostic report as an aid for determination of referral to inpatient rehabilitation]

The investigation analyzes some 206 standardized diagnostic reports submitted by office-practice physicians, demonstrating the role of diagnostic reports in determining access to medical rehabilitation. It is found that the practitioners added no further information about their patients' health status in half of the diagnostic reports given, and no further medical documents in one third. On the other hand, diagnostic reports that included details about the patients' ability to work as well as information about previous treatments resulted to a greater degree in direct award of a medical rehabilitation measure.

Effects of simulated microgravity (HDT) on blood fluidity

Exposures to microgravity and head-down tilt (HDT) produce similar changes in body fluid. This causes an increase in hematocrit that significantly affects hemorheological values. Lack of physical stimulation under bed rest conditions and the relative immobility of the crew during spaceflight also affects the blood fluidity. A group of six healthy male subjects participated as volunteers, and blood samples were collected 10 days before, on day 2 and day 9, and 2 days after the HDT phase. Blood rheology was quantified by plasma viscometry, red cell aggregability, and red cell deformability. A reduced red cell deformability, an indication of the diminished quality of the red blood cells, was measured under HDT conditions that finally led to the so-called "space flight anemia." Enhanced red cell membrane fragility induced by diminished physical activity and an increase in hemoglobin concentration are responsible for this effect. Plasma viscosity is reduced as a result of diminished plasma proteins. However, despite the reduction in plasma proteins, including fibrinogen, alpha 2-macroglobulin, and immunoglobulin M, red cell aggregation was enhanced, principally because of the increase in hematocrit. Our results of hemorheological alterations under HDT conditions may help to elucidate the formerly documented hematologic changes during spaceflight.

Assessment of effects of a radiofrequency energy field and thermistor location in an electrode catheter on the accuracy of temperature measurement

Accurate measurement of temperature at the interface of the delivery electrode and the tissue during transcatheter delivery of radiofrequency energy (RFE) for ablation would provide better control of lesion production. Electromagnetic energy fields can affect the accuracy of temperature measurement with thermistors. An electrode probe was fabricated with a thermistor and an optical sensor in the center of the delivery electrode. Simultaneous temperature measurements during RFE delivery to cardiac tissue in the 37 degrees C bath showed good agreement between the sensors, indicating that the RFE field did not cause errors in thermistor temperature measurements with the electrode probe used. A second electrode probe was designed to determine optimal thermistor location. It was constructed using two thermistors with identical temperature-resistance curves. One thermistor protruded through a hole in the side of the delivery electrode and was thermally isolated from it. The other thermistor was bonded to the inner surface of the electrode with heat conductive epoxy. The electrode was placed in contact with cardiac tissue in a 37 degrees C bath of flowing saline with the protruding thermistor centered in the area to be heated. Temperatures measured at steady state during RFE delivery with the protruding thermistor were consistently higher than those of the inner wall thermistor, ranging from 1.8 degrees C difference at 46 degrees C to 8.3 degrees C difference at 75 degrees C interface temperature. The thermistor must be in contact with the tissue and thermally isolated from the delivery electrode for accurate determination of electrode/tissue interface temperature.

Effective contraception with the levonorgestrel-releasing intrauterine device: 12-month report of a European multicenter study

The use-effectiveness of an intrauterine contraceptive device releasing 20 mcg of levonorgestrel daily (Lng-IUD), and of a Nova T copper-releasing IUD, were studied in a randomized, comparative multicenter trial. The Lng-IUD was inserted in 1821, and the Nova T in 937 women. The 12-month net pregnancy rate with the Lng-IUD (0.1 per hundred women) was significantly lower than that with the Nova T (0.9 per hundred). Removal rates for menstrual problems and/or pain were similar for the two methods (net rates 7.5 and 8.7, respectively). The 12-month continuation rates were 82.2 for the Nova T and 79.7 for the Lng-IUD. The reduction of the bleeding led to oligomenorrhea and amenorrhea in users of the Lng-IUD; the removal rate for these reasons was 1.4. The removal rate for hormonal side effects with the Lng-IUD was 2.4. Blood hemoglobin concentrations increased among users of the Lng-IUD and decreased among users of the Nova T. The results show that the Lng-IUD was a highly effective contraceptive method which reduced menstrual bleeding. It is a promising alternative for women desiring a highly effective method for long-term use.

A comparison between Nova T and Copper T 200 Ag in Hungary

In a comparative use-effectiveness study, 855 Nova T and 883 TCu 200 Ag devices were inserted in a randomised sequence. By the end of the first year the gross rate of unplanned pregnancy was 1.1 per 100 users of Nova T and 2.1 per 100 users of TCu. After 2 years the pregnancy rates for Nova T and TCu were 3.1 and 4.8 per 100 users, respectively. Although there was no statistically significant difference between the rates for the two devices, they suggest a higher contraceptive efficacy for Nova T.

"Menstrual induction" with Sulproston

The PGE2-analogue Sulproston (16-phenoxy-omega-17,18,19,20-tetranor-PGE2-mythylsulfonylamide) was administered to 200 medically and gynecologically normal women who were 17 +/- 0.4 days beyond their expected menstrual period and who had a positive pregnancy test. The intramuscular impact dose (500 micrograms repeated after 4 hours) caused an immediate tonic uterine contraction which compromised the estradiol 17 beta, progesterone and chorionic gonadotropin production within the fetoplacental unit, and thereby allowed the evolution of cyclic uterine activity, cervical dilatation and tissue expulsion. Pregnancy termination was complete in 92% of women, 5.5% required surgical curettage and 2.5% were given a second Sulproston treatment 2-3 weeks after the first to remove retained tissue from the uterus. The medical induction of menstruation was preferred by 83% of the women who had previously experienced surgical termination of pregnancy. Normal menstruation resumed in all women after 36 +/- 0.9 days. The majority of 42 women questioned found Sulproston a satisfactory, safe, simple and effective drug regimen for "menstrual induction".