B2LiVe, a label-free 1D-NMR method to quantify the binding of amphitropic peptides or proteins to membrane vesicles

Amphitropic proteins and peptides reversibly partition from solution to membrane, a key process that regulates their functions. Experimental approaches classically used to measure protein partitioning into lipid bilayers, such as fluorescence and circular dichroism, are hardly usable when the peptides or proteins do not exhibit significant polarity and/or conformational changes upon membrane binding. Here, we describe binding to lipid vesicles (B2LiVe), a simple, robust, and widely applicable nuclear magnetic resonance (NMR) method to determine the solution-to-membrane partitioning of unlabeled proteins or peptides. B2LiVe relies on previously described proton 1D-NMR fast-pulsing techniques. Membrane partitioning induces a large line broadening, leading to a loss of protein signals; therefore, the decrease of the NMR signal directly measures the fraction of membrane-bound protein. The method uses low polypeptide concentrations and has been validated on several membrane-interacting polypeptides, ranging from 3 to 54 kDa, with membrane vesicles of different sizes and various lipid compositions.

Dynamics and structural changes of calmodulin upon interaction with the antagonist calmidazolium

Background

Calmodulin (CaM) is an evolutionarily conserved eukaryotic multifunctional protein that functions as the major sensor of intracellular calcium signaling. Its calcium-modulated function regulates the activity of numerous effector proteins involved in a variety of physiological processes in diverse organs, from proliferation and apoptosis, to memory and immune responses. Due to the pleiotropic roles of CaM in normal and pathological cell functions, CaM antagonists are needed for fundamental studies as well as for potential therapeutic applications. Calmidazolium (CDZ) is a potent small molecule antagonist of CaM and one the most widely used inhibitors of CaM in cell biology. Yet, CDZ, as all other CaM antagonists described thus far, also affects additional cellular targets and its lack of selectivity hinders its application for dissecting calcium/CaM signaling. A better understanding of CaM:CDZ interaction is key to design analogs with improved selectivity. Here, we report a molecular characterization of CaM:CDZ complexes using an integrative structural biology approach combining SEC-SAXS, X-ray crystallography, HDX-MS, and NMR.

Results

We provide evidence that binding of a single molecule of CDZ induces an open-to-closed conformational reorientation of the two domains of CaM and results in a strong stabilization of its structural elements associated with a reduction of protein dynamics over a large time range. These CDZ-triggered CaM changes mimic those induced by CaM-binding peptides derived from physiological protein targets, despite their distinct chemical natures. CaM residues in close contact with CDZ and involved in the stabilization of the CaM:CDZ complex have been identified.

Conclusion

Our results provide molecular insights into CDZ-induced dynamics and structural changes of CaM leading to its inhibition and open the way to the rational design of more selective CaM antagonists.

Graphical abstract

Calmidazolium is a potent and widely used inhibitor of calmodulin, a major mediator of calcium-signaling in eukaryotic cells. Structural characterization of calmidazolium-binding to calmodulin reveals that it triggers open-to-closed conformational changes similar to those induced by calmodulin-binding peptides derived from enzyme targets. These results provide molecular insights into CDZ-induced dynamics and structural changes of CaM leading to its inhibition and open the way to the rational design of more selective CaM antagonists.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-022-01381-5.

Influence of Transcranial Direct Current Stimulation on Psychomotor Symptoms in Major Depression

Background: Transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal cortex (dlPFC) might be a promising treatment strategy for depression. As disturbances in psychomotor activity are one of the key features of unipolar depression are, we aimed to evaluate the behavioral effects of ten tDCS sessions over a 5-day period on psychomotor retardation in depressed patients. Methods: Twenty-three treatment-resistant depressed patients received either active or sham anodal tDCS to the left dorsolateral prefrontal cortex (2 mA, 10 sessions over 1 week). Psychomotor functioning was registered by means of observer ratings (Salpêtrière Retardation Rating Scale—SRRS) and objective measures (kinematical analysis of movements, automatic imitation). Results: tDCS sessions resulted in improvements on SRRS scores, although active tDCS was not significantly superior to sham tDCS on the kinematical parameters. Furthermore, no general additional antidepressant effect of tDCS was observed. The relatively small sample size and the short periods of observation should be considered when interpreting these results. Conclusion: tDCS did not induce a clinically relevant effect on psychomotor function in active and sham stimulation groups.

Impact of urine and mixed incontinence on long-term care preference: a vignette-survey study of community-dwelling older adults

BACKGROUND

In view of population aging, a better knowledge of factors influencing the type of long-term care (LTC) among older adults is necessary. Previous studies reported a close relationship between incontinence and institutionalization, but little is known on opinions of older citizens regarding the most appropriate place of care. This study aimed at evaluating the impact of urine and/or fecal incontinence on preferences of community-dwelling older citizens.

METHODS

We derived data from the Lausanne cohort 65+, a population-based study of individuals aged from 68 to 82 years. A total of 2974 community-dwelling persons were interviewed in 2017 on the most appropriate place of LTC delivery for three vignettes displaying a fixed level of disability with varying degrees of incontinence (none, urinary, urinary and fecal). Multinomial logistic regression analyses explored the effect of respondents' characteristics on their opinion according to Andersen's model.

RESULTS

The level of incontinence described in vignettes strongly determined the likelihood of considering institutional care as most appropriate. Respondents' characteristics such as age, gender, educational level, being a caregiver, knowledge of shelter housing or feeling supported by family influenced LTC choices. Self-reported incontinence and other indicators of respondents' need, however, had no significant independent effect.

CONCLUSION

Among older community-dwelling citizens, urinary and fecal incontinence play a decisive role in the perception of a need for institutionalization. Prevention and early initiation of support for sufferers may be a key to prevent this need and ensure familiar surrounding as long as possible.

Abstract P6-08-25: Outcome of breast cancer patients treated in the private health care in Brazil

Background

Developing countries like Brazil often present a dichotomous health care system, where patients may be treated in either public or private institutions that differ substantially in terms of level of access to diagnostic and therapeutics procedures. Herein, we present the first report of a comprehensive study to assess real-world data in breast cancer patients treated in the private health care in Brazil.

Methods

This is a prospective study of breast cancer patients treated in a private health care institution, comprising six unities in Rio de Janeiro and surroundings. Eligible patients were at least 18 years old and had a histology-proven diagnosis of breast cancer between July 2012 and November 2016. For this analysis, only female patients with an invasive component were included. Patients with prior malignancies and those who initiated therapy in other institutions were excluded. Patients or relatives were contacted by telephone to ensure that all information was annotated. Data quality was certified by regular monitoring. This study was approved by the local Research Ethics Committee.

Results

One thousand three hundred and ninety patients were enrolled. One hundred sixty were excluded in this analysis, 11 due to male gender and 151 with exclusively in situ carcinoma. The report comprises 1230 female patients, predominantly diagnosed in early (79.0% stages I-II) or locally advanced (16.1% stage III) stages. One thousand thirty-three (84.0%) patients had hormone receptor (HR)-positive tumors, and 185 (15.0%) were HER2 positive. One hundred twenty-six (10.2%) cases were triple negative. The primary tumor was resected in 89.0% of times, most often through breast-conserving surgery (55.1%). Axillary lymph nodes were assessed in 83.4% of cases, and 32.0% required complete axillary dissection. Chemotherapy was used in 61.3% of cases, and radiation therapy in 59.6%. Patients with locally advanced disease received more aggressive therapy than patients with early stage (higher rates of mastectomy, axillary dissection and chemotherapy use). After a median follow up of 22.5 months (95% CI, 21.09-23.90), 54 (4.4%) deaths were reported. The estimated 2-year overall survival (OS) was 95.3%. 2-year OS was significantly longer among patients with stages I-II (97.9% and 97.5%, respectively) than in stages III and IV (89.4% and 69.5%, respectively) (p<0.01). HER2/HR status (p<0.01) and tumor grade (p=0.05) were also correlated to OS in the overall cohort, however triple-negative cases were only prognostic in stage III. Age (p=0.10), menopausal status (p=0.74), and histological subtype (p=0.55) were not correlated to OS.

Conclusion

To our knowledge, this is the most comprehensive and best-annotated study in breast cancer patients treated in the private health care in Brazil. More oncological interventions were used in advanced stages, reflecting international recommendations, but also a need to pursue early diagnoses, where outcome is optimal despite less aggressive therapy. Outcomes are favorably similar to the current literature from developed countries in all stages. The data provided helps comprehending the current scenario of breast cancer presentation and treatment in Brazil, and may serve as a foundation to guide resource allocation in the years to come.

Citation Format: Boukai A, Gonçalves AC, Andrade PM, Carvalho N, Almeida T, Lemos F, Padoan M, Teich NS, Araujo LH. Outcome of breast cancer patients treated in the private health care in Brazil [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-25.

Analysis of genetic variability of commercial melon cultivars using SSR molecular markers

Taking into account the scenario of melon production (Cucumis melo L.) in Brazil, it is notable the importance of the culture in the fruit market. The preference of the national market is concentrated in the fruits of the yellow type. Therefore, it is possible that the genetic base of the commercial cultivars is relatively narrow due to the loss of important genes in the breeding process, and it is possible to introgress external genes for increasing recombination possibilities that generate sources of resistance to the main diseases and superior genotypes. This study evaluated the genetic variability of 87 melon accessions composed of 72 commercial cultivars belonging to the Inodorus and Cantaloupensis groups and 15 plant introductions (PIs). Forty-four polymorphic SSR primers were used to amplify a total of 202 alleles. The expected heterozygosity presented an average of 0.519 and the PIC index of 0.458, being moderately informative. The dendrogram generated for the 72 cultivars grouped the genotypes into 2 main groups, and there was no association with the classification of groups of the genotypes in the grouping. The number of SSR markers was sufficient to predict wide genetic variability among the cultivars studied, with the similarity between 0.35 and 0.98. The dendrogram presented for the 72 cultivars and the 15 PI genotypes was not associated with the classification of the genotypes in the grouping, and the 15 PIs were well dispersed with similarity indexes that resemble the two groups studied. A set of 25 primers was identified that were useful in distinguishing the 72 cultivars. These primers can be used in later research with the cultivars, as well as in crop protection situations, being an important tool in the useful and rapid distinction of genotypes, and in commercial disputes regarding the certification of the main melon cultivars used in the country.

Handwriting in Children and Adults With Down Syndrome: Developmental Delay or Specific Features?

While there is a long history and tradition of behavioral research on basic motor skills in Down syndrome (DS), there has been only limited research on handwriting ability. We analyzed the spatiotemporal features of handwriting produced by children and adults with DS (n = 24), and compared their productions with those of comparison groups matched for developmental (n = 24) or chronological (n = 24) age. Results indicated that the participants with DS performed an alphabet letter-writing task just as efficiently as the children of the same developmental age, in terms of the length, duration and speed of their handwriting, and the number and duration of their pauses. Our study highlights a substantial delay in the stages of writing acquisition.

A Prospective Intervention in Patients with Complicated Grief

Introduction

Most reactions to grief are adaptive. However, there is the possibility that some individuals present a complicated grief disorder, where there is a pathological intensification of symptoms lasting more than 6 months, deserving special treatment.

Objectives/aims

Evaluate the effectiveness of two types of intervention in complicated grief: group intervention (GI) and cognitive-narrative (CN) therapy.

Methods

Patients in a complicated grief process were selected (n = 70), and distributed in three groups: cognitive–narrative therapy group (CNTG), group intervention group (GIG) and a control group (CG). Inclusion criteria: adults, with a reference to mourning situation, with personal meaning, for over six months and results in ICG ≥30points (cutoff). The Inventory of Complicated Grief (ICG), the Center for epidemiologic studies depression scale (CES-D) and the trauma questionnaire (ICD-11) were used. Follow-up was performed 3 months after the end of each intervention. Data analysis was performed using the statistical package from social sciences (SPSS 20).

Results

With respect to complicated grief symptoms (CGx) and depression symptoms (Dx) there were statistically significant differences between the CNTG and the CG, but not with the GIG. There was no statistically significant effect in post-traumatic symptoms (PTx), even though both interventions had a slight decrease. When the CNTG and the GIG were directly compared, there was only a statistically significant difference between PTx.

Conclusions

In our single center cohort, CNTG was a more effective intervention in complicated grief patients for CGx and Dx reduction. For PTx, no intervention was superior. Larger multi-center studies are needed to validate these results.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Eye Movement in Unipolar and Bipolar Depression: A Systematic Review of the Literature

BACKGROUND

The analysis of eye movements (EM) by eye-tracking has been carried out for several decades to investigate mood regulation, emotional information processing, and psychomotor disturbances in depressive disorders.

METHOD

A systematic review of all English language PubMed articles using the terms "saccadic eye movements" OR "eye-tracking" AND "depression" OR "bipolar disorders" was conducted using PRISMA guidelines. The aim of this review was to characterize the specific alterations of EM in unipolar and bipolar depression.

RESULTS

Findings regarding psychomotor disturbance showed an increase in reaction time in prosaccade and antisaccade tasks in both unipolar and bipolar disorders. In both disorders, patients have been reported to have an attraction for negative emotions, especially for negative pictures in unipolar and threatening images in bipolar disorder. However, the pattern could change with aging, elderly unipolar patients disengaging key features of sad and neutral stimuli. METHODological limitations generally include small sample sizes with mixed unipolar and bipolar depressed patients.

CONCLUSION

Eye movement analysis can be used to discriminate patients with depressive disorders from controls, as well as patients with bipolar disorder from patients with unipolar depression. General knowledge concerning psychomotor alterations and affective regulation strategies associated with each disorder can also be gained thanks to the analysis. Future directions for research on eye movement and depression are proposed in this review.

Visual scanning behavior during processing of emotional faces in older adults with major depression

OBJECTIVES

Although several reported studies have suggested that younger adults with depression display depression-related biases during the processing of emotional faces, there remains a lack of data concerning these biases in older adults. The aim of our study was to assess scanning behavior during the processing of emotional faces in depressed older adults.

METHOD

Older adults with and without depression viewed happy, neutral or sad portraits during an eye movement recording.

RESULTS

Depressed older adults spent less time with fewer fixations on emotional features than healthy older adults, but only for sad and neutral portraits, with no significant difference for happy portraits.

CONCLUSION

These results suggest disengagement from sad and neutral faces in depressed older adults, which is not consistent with standard theoretical proposals on congruence biases in depression. Also, aging and associated emotional regulation change may explain the expression of depression-related biases. Our preliminary results suggest that information processing in depression consists of a more complex phenomenon than merely a general searching for mood-congruent stimuli or general disengagement from all kinds of stimuli. These findings underline that care must be used when evaluating potential variables, such as aging, which interact with depression and selectively influence the choice of relevant stimulus dimensions.

Motor imagery in unipolar major depression

Background: Motor imagery is a potential tool to investigate action representation, as it can provide insights into the processes of action planning and preparation. Recent studies suggest that depressed patients present specific impairment in mental rotation. The present study was designed to investigate the influence of unipolar depression on motor imagery ability.

Methods: Fourteen right-handed patients meeting DSM-IV criteria for unipolar depression were compared to 14 matched healthy controls. Imagery ability was accessed by the timing correspondence between executed and imagined movements during a pointing task, involving strong spatiotemporal constraints (speed/accuracy trade-off paradigm).

Results: Compared to controls, depressed patients showed marked motor slowing on both actual and imagined movements. Furthermore, we observed greater temporal discrepancies between actual and mental movements in depressed patients than in healthy controls. Lastly, depressed patients modulated, to some extent, mental movement durations according to the difficulty of the task, but this modulation was not as strong as that of healthy subjects.

Conclusion: These results suggest that unipolar depression significantly affects the higher stages of action planning and point out a selective decline of motor prediction.

Saccadic eye movements in depressed elderly patients

The primary aim of this study was to characterize oculomotor performances in elderly depressed patients. The second aim was to investigate whether cognitive inhibition measured by the antisaccade task was associated with a psychomotor retardation or rather with a more specific cognitive-motor inhibition deficit. Twenty patients with a major depressive disorder and forty-seven healthy subjects performed two eye movement tasks. Saccadic reaction time and error rates were analyzed in the prosaccade task to obtain basic parameters of eye movements. Saccade latency, error rates and correction rates were evaluated in the antisaccade task to investigate inhibition capacities. Performances were impaired in patients, who exhibited a higher reaction time and error rates compared to controls. The higher time cost of inhibition suggested that the reaction time was not related to global psychomotor retardation alone. The higher time cost of inhibition could be explained by a specific alteration of inhibition processes evaluated by the antisaccade task. These changes were associated with the severity of depression. These findings provide a new perspective on cognitive inhibition in elderly depressed patients and could have important clinical implications for our understanding of critical behaviors involving deficits in inhibitory processes in the elderly.

Allergic vulvovaginitis in infancy: study of a case

BACKGROUND

the role of dust mites (Dermatophagoides pt.) in the pathogenesis of allergic vulvovaginitis is still controversial. Association between this mite and atopic dermatitis, conjunctivitis, rhinitis or asthma is already known. Some authors study the possible relationship between some vulvovaginitis and local hypersensitivity. The aim of this study was to corroborate the allergic aetiology due to the mite Dermatophagoides pt. in a girl with vulvovaginitis and perennial rhinitis.

METHODS AND RESULTS

we studied a nine year-old patient with symptoms of perennial rhinitis and unspecific vulvovaginitis of torpid evolution. In vivo and in vitro allergologic tests were performed as well as complete analytic tests including immunoglobulins, urine tests, nasal culture, exudative vaginal culture, and parasitic test. Skin test was positive for Dermatophagoides pt. as well as specific IgE (99.5 kU/L). Total IgE was elevated for her age (492 kU/L). In the rest of the complementary tests, no values out of normality or pathological findings were obtained.

CONCLUSIONS

considering these results, it was suspected that the nasal symptoms and the vulvovaginitis presented by the patient are of allergic aetiology by hypersensitivity to the mite Dermatophagoides pt. The study did not prove relation with bacteria, parasites, Candida albicans or any inhalant allergens other than mites. After three months of treatment with oral antihistamines and topical chromones, as well as environmental avoiding measures, the symptoms totally yielded.

International Study of Asthma and Allergies in Childhood. Results on rhinitis of first phase in Pamplona, Spain

BACKGROUND

The ISAAC (International Study of Asthma and Allergies in Childhood) was thought in order to maximize the value of epidemiological research into asthma and allergic diseases in childhood, establishing a standardized methodology and facilitating collaboration and comparison between several countries.

METHODS AND RESULTS

The written questionnaires in the group of children aged 6-7 years was answered by the parents and the group of children aged 13-14 years self-completed the written questionnaires.

RESULTS

3,040 children aged 13-14 years answered the questionnaire and 3,002 in the group aged 6-7 years. In the group of children aged 13-14, 49.7% referred rhinitis symptoms some time, and 15.6% in the 6-7 year old group. The prevalence of nasal symptoms in the last year was 35.5% in the 13-14 year group and 10.6% in the 6-7 year group. The presence of nasal symptoms was more frequent in winter. The prevalence of seasonal allergic rhinitis (hay fever) was 6.1% in the 13-14 year group and 4.8% in the group of children aged 6-7 years.

CONCLUSIONS

These results can contribute to a better control of some factors and to future studies where the etiology and incidence of the disease could be investigated.

Osteoarthropathy of hepatolenticular degeneration

Ninety-six joints of 25 patients with hepatolenticular degeneration have been studied by means of scintigraphs with technetium (99mTc), a method which can disclose early synovial inflammation and postinflammatory articular degeneration. Signs of synovitis were found in 22 joints of 10 patients (40%) and degenerative changes were present in 15 joints of eight patients (32%). Eleven patients complained of joint pains; in four of them they were the presenting symptom. The radiological study showed osteoporosis in 22 patients (88%); flexion deformity was found in two cases, anomalous osteophytes in two, and signs of growth arrest, features of rheumatoid arthritis and aseptic necrosis in one case each. The pathogenesis of osteoarticular changes in Wilson's disease is discussed.

Studies on thyroid and hypophysary thyrotrophic hormone (TSH) in Down syndrome

Serum TSH was studied in 22 patients with Down syndrome, from 4 to 15 years old. In 6 of these patients radioidine uptake by thyroid gland after 2 and 24 hours of administration and clearance rates before and after TSH stimulus (10 mul-IM) were measured. Results show that serum TSH was normal in 17 patients and above normal limits in 5 patients. Thyroid uptake after 2 hours as well clearance rates, both below normal, had a response to TSH stimulus with normal or below values. These data along with previous reports, suggest, that in children with Down syndrome, there is a thyroid dysfunction in which a slow response no TSH stimulus seems to be the basic defect.

Studies of the thyroid function in children with Down's syndrome

The thyroid function (T-3 triiodothyronine; T-4 tetraiodothyronine and the captation of the I131 through the thyroid, in 2 and 24 hours after the intake of isotope radium), was studied in patients with Down's syndrome and the results being compared to those obtained from the respective siblings, all clinically normal. The comparative results showed no significant differences, except in the 2 hours captation of the I131 through the thyroid (P smaller than 0.01). The findings suggest that the hypothalamus-hypophysary or the response of the thyroid gland would be slow, but compensated when analyzed after 24 hours.