Cytogenetic analysis of Triatoma pseudomaculata Corrêa and Espínola, 1964 (Hemiptera, Triatominae) from different Brazilian states

Triatoma maculata and T. pseudomaculata are allopatric; however, it is believed that T. maculata was introduced into the Brazilian northeast by passive transportation of the nymphs between the feathers of migratory birds, followed by the speciation of T. pseudomaculata. T. pseudomaculata is the second most epidemiologically important species in the northeast of Brazil after T. brasiliensis. Therefore, given the broad range of T. pseudomaculata, the objective of the present study was to cytogenetically analyze different populations of T. pseudomaculata from different Brazilian states in order to investigate possible intraspecific chromosomal variation between them. Three adult T. pseudomaculata males from each population (Pernambuco, Ceará, Paraíba, Bahia, Rio Grande do Norte, and Piauí) were analyzed by lacto-acetic orcein and C-banding. All of the specimens analyzed exhibited the same cytogenetic characteristics, i.e., 22 chromosomes (20 autosomes and XY), a chromocenter formed by the X and Y sex chromosomes and one pair of autosomes, and heterochromatin blocks in three or four pairs of autosomes. These data confirm that all of the populations analyzed were T. pseudomaculata, and although they may be subject to different selection pressures they have maintained the genetic integrity that characterizes the species.

Insights into a hotspot in the Brasiliensis subcomplex (Hemiptera, Triatominae) by analysis of D2 domain of the nuclear gene 28S

The Brasiliensis subcomplex is a monophyletic group formed by the species Triatoma brasiliensis brasiliensis, T. b. macromelasoma, T. juazeirensis, T. melanica, and T. sherlocki. However, using cytogenetic data and experimental hybrid crosses, T. lenti and T. petrochiae were also grouped into this subcomplex. This study aims to analyze the properties of hotspot in the D2 domain of the nuclear gene 28S in all species of the Brasiliensis subcomplex as well as T. lenti and T. petrochiae. These species show two transversions at position 385 (G↔C and T↔G). We suggest that this mutation in haplotype 4 may be an initial molecular tool that supports the relationship of these species with the subcomplex. In addition to the transversion at haplotype 4, these species, aside from T. melanica, also possess a transversion at position 385 (G↔T) in haplotype 1. Thus, we describe the hotspot mutations of the D2 domain of the nuclear gene 28S for species in Brasiliensis subcomplex as follows: three transversions are present at position 385 of haplotypes 1 and 4, which are shared by members of the subcomplex as well as T. lenti and T. petrochiae. These transversions may be considered a synapomorphy between these species. However, we emphasize that new phylogenetic studies should be conducted to evaluate whether T. lenti and T. petrochiae are truly members of the Brasiliensis subcomplex.

Spermiotaxonomy of the tribe Rhodniini (Hemiptera, Triatominae)

The tribe Rhodniini is a monophyletic group composed of 22 species, with 19 in the Rhodnius genus and three in the Psammolestes genus. These insects are morphologically very similar (cryptic species), and new tools are important for investigating the taxonomy of these vectors. Spermiotaxonomy is an important tool in differentiating between related species, and this study analyzed the spermatids of Rhodniini species to elucidate their spermiotaxonomy. All of the Rhodniini species contained two heteropyknotic filaments in the extremities of their cells. Although spermiotaxonomy has been an important tool in differentiating between species of the Triatoma genus, all of the species in the Rhodnius genus exhibited the same characteristics in their male gametes. However, spermatid analysis made it possible to confirm the monophyly of the Rhodniini tribe, because Psammolestes tertius had the same pattern as that described for Rhodnius. The results of this study demonstrate that spermiotaxonomy, in addition to being an important tool for differentiating between related species of Triatoma, can be used as an optimization tool in phylogenetic analyses.

Adverse effects in repetitive transcranial magnetic stimulation – prevention and management

Introduction

Repetitive Transcranial Magnetic Stimulation (rTMS), through modulation of cortical activity, has become an invaluable tool in experimental and clinical neurosciences. Although this form of noninvasive treatment is considered safer than other means of brain stimulation it has been associated with adverse effects (AE).

Objective

To make a brief review, concerning the AE of rTMS, their prevention and management.

Aims

To understand and be able to deal with the most common AE associated with rTMS.

Methods

A PubMed database search, using as keywords “Transcranial magnetic stimulation”, “Repetitive Transcranial magnetic stimulation”; “adverse effects”; “management” and “guidelines” between the year 1998 and 2015.

Results

AE caused by rTMS are rare. They can be classified into severe (seizures) and mild (syncope, and transient hearing impairment, acute psychiatric changes, headache, local pain, neck pain, toothache, paresthesia and cognitive/neuropsychological changes) and into early and late AE. In order to obviate and avoid them, guidelines have been created; some state that to apply rTMS the technician needs to obtain the patient's informed consent and assess the risks/benefit ratio. To meet these criteria, screening tools have been created, and since then the number of AE has reduced.

Conclusions

Even though rTMS is considered safer than other forms of brain stimulation it is still associated with AE. In order to avoid them, screening tools have been created allowing the clinician to assess the risks and benefits of applying this technique.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

A review of transcranial magnetic stimulation for treating negative symptoms of schizophrenia

Introduction

The finding of prefrontal dysfunction in schizophrenia patients with negative symptoms (NS) has raised interest in using transcranial magnetic stimulation (TMS), which can modulate prefrontal function and dopamine release, as potential treatment for NS.

Objective

To briefly review current literature concerning the use of TMS as treatment for NS.

Aims

To assess whether current evidence supports the use of TMS for NS.

Methods

Narrative review of articles found through a PubMed database search using the keywords “transcranial magnetic stimulation”, “schizophrenia”, and “negative symptoms” between 1998 and 2015.

Results

Up to date, reviews of randomized sham-controlled studies found positive effects of TMS in NS. However, they exposed several methodological difficulties. More recent studies, reviewed in this poster, tried to overcome these, using results from multiple centers, larger samples and blinding. Various TMS techniques were studied, differing in frequency, motor threshold (MT), stimulus location, and treatment duration. Overall, TMS continues to show promising results in reducing NS; particularly rTMS 10 Hz, for at least 15 sessions on the left dorsolateral prefrontal cortex (DLPFC) at a 110% MT.

Conclusions

TMS may be a useful treatment for NS for patients not responding to pharmacological treatment alone. Studies remain difficult to compare due to different measures of outcome (PANSS and SANS being the most commonly used) and techniques. Furthermore, possible modulators of response include duration of illness, cognitive symptoms amelioration, medication and their dose, and different NS may respond differently to TMS. More studies are needed to better understand the utility of TMS in NS.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Atypical psychosis – historical and current perspective

Introduction

Clinical concepts regarding atypical psychosis such as the French bouffeé délirante, the German cycloid psychosis, and the Scandinavian reactive and schizophreniform psychoses are now under the category of F23 ‘Acute and transient psychotic disorders’ (ATPD) of the tenth revision of the International Classification of Mental and Behavioural Disorders (ICD-10).

Aims

The authors’ aim is to highlight the clinical and scientific relevance of atypical psychosis from the historical concepts to the current perspective.

Methods

A Pubmed database search using as keywords “atypical psychosis”, “acute and transient psychotic disorders”, and “brief psychotic disorder” and retrieved papers were selected according to their relevance.

Results

Different psychiatric schools, often of a regional or national character, have provided concepts for transient psychotic states. The acute and transient psychotic disorders of ICD-10 and the brief psychotic disorder of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) reflect the diversity of the history of such concepts. The available evidence suggests that case identification and follow-up is difficult in ATPD due to the heterogeneous and infrequent nature of this clinical phenomenon. Furthermore ATPD has a low diagnostic stability and there are few studies focused on brief psychotic disorders.

Conclusions

The present definition of acute and transient psychotic disorders and brief psychotic disorder, while taking into account the history of the concepts involved, leave many questions open to further studies.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Should fetal scalp blood sampling be performed in the case of meconium-stained amniotic fluid?

OBJECTIVE

To investigate the effect of using fetal scalp blood sampling on the risk of neonatal respiratory distress syndrome (NRDS) with meconium-stained amniotic fluid (MSAF).

METHODS

Prospective data collection with regard to MSAF during labor for low-risk term cephalic singleton live birth from 2012 to 2014. Maternal, obstetric and neonatal data were compared according to the occurrence of respiratory distress syndrome (RDS group) or not (no RDS group).

RESULTS

Of 515 newborns born through MSAF, 46 experienced RDS and from them 10 experienced meconium aspiration syndrome. No difference was observed according to maternal characteristic, abnormal fetal heart rate tracing pattern irrespective of its category and cesarean rate. Apgar at one minute was lower in the group RDS (7.6 versus 8.5, p < 0.05). The mean umbilical artery pH values did not differ between the two groups. Significant difference between newborns with and without RDS in terms of fetal scalp lactate sampling during the labor (71.1% versus 55.1%, p < 0.05), and neonatal care unit (NCU) admissions (22.8% versus 10.8%, p < 0.05). Secondary rather than primary meconium was associated with RDS when performing fetal scalp blood assessment (p < 0.05). A significant correlation between RDS, fetal scalp blood assessment and MSAF diagnosed during the first stage of labor (after spontaneous rupture of membranes or at amniotomy) was found.

CONCLUSION

In case of MSAF, fetal scalp blood sampling did not reduce the risk of RDS.

Exercise-based cardiac rehabilitation increases daily physical activity of patients following myocardial infarction: subanalysis of two randomised controlled trials

OBJECTIVE

To assess the effects of an exercise-based cardiac rehabilitation programme on daily physical activity levels of patients following myocardial infarction.

DESIGN

Subanalysis of two randomised, prospective controlled trials.

SETTING

Outpatient clinic of a secondary hospital.

PARTICIPANTS

Fifty consecutive patients randomised to the exercise group {n=25; 23 males; mean age 54 [standard deviation (SD) 9] years} or the control group [n=25; 20 males; mean age 58 (SD 9) years].

INTERVENTIONS

The exercise group participated in an 8-week aerobic exercise programme plus usual medical care and follow-up. The control group received usual medical care and follow-up.

MAIN OUTCOME MEASURES

The primary outcome measure was change in time spent undertaking moderate-to-vigorous physical activity per day, assessed by accelerometer over 7 consecutive days. Secondary outcome measures were cardiorespiratory fitness, body mass, and resting blood pressure and heart rate.

RESULTS

Moderate-to-vigorous physical activity levels increased significantly in the exercise group [43.2 (SD 36.3) to 53.5 (SD 31.9) minutes/day, P=0.030], and remained unchanged in the control group [40.8 (SD 26.2) to 36.8 (SD 26.5) minutes/day, P=0.241] from baseline to the end of the programme. Cardiorespiratory fitness increased significantly in the exercise group (mean difference 2.8; 95% of the difference 1.3 to 4.4ml/kg/minute, P=0.001) after the 8-week programme.

CONCLUSIONS

In patients under optimal medication following myocardial infarction, participation in an 8-week exercise-based cardiac rehabilitation programme was found to improve physical activity levels consistent with health-related benefits. Future studies are needed to determine whether the increase in physical activity is maintained in the long term.

Evaluation of Cognitive Functions through the Systemic Lisbon Battery: Normative Data

INTRODUCTION

This article is part of the Focus Theme of Methods of Information in Medicine on "Methodologies, Models and Algorithms for Patients Rehabilitation".

BACKGROUND

ICT is an emerging alternative to paper-and-pencil tests for the assessment of cognitive functions, allowing for the monitoring of participants' behavior while they perform simulations of instrumental activities of daily life (IADLs) in a virtual reality (VR) scenario. This requires normative values for each VR task, so that deviations to normality can be identified as indicators of cognitive impairment.

OBJECTIVES

To identify normative data for several IADL tasks that are available on the Systemic Lisbon Battery (SLB).

METHODS

Fifty-nine participants performed a series of VR tasks that require the use of the memory and executive function dimensions of cognitive functionality.

RESULTS

Normative data for the different subsets and total score of the SLB, based on proportion of correct hits per execution time, were identified. Age and experience with video games affect (respectively, negatively and positively) performance on the SLB and should be taken into account in assessment; on the other hand, gender and education do not.

CONCLUSIONS

Overall results suggest that the SLB may be useful to assess cognitive functioning during the execution of activities of daily living, but larger studies and with clinical samples are needed.

Unravelling the relationship between protein sequence and low-complexity regions entropies: Interactome implications

Low-complexity regions are sub-sequences of biased composition in a protein sequence. The influence of these regions over protein evolution, specific functions and highly interactive capacities is well known. Although protein sequence entropy has been largely studied, its relationship with low-complexity regions and the subsequent effects on protein function remains unclear. In this work we propose a theoretical and empirical model integrating the sequence entropy with local complexity parameters. Our results indicate that the protein sequence entropy is related with the protein length, the entropies inside and outside the low-complexity regions as well as their number and average size. We found a small but significant increment in the sequence entropy of hubs proteins. In agreement with our theoretical model, this increment is highly dependent of the balance between the increment of protein length and average size of the low-complexity regions. Finally, our models and proteins analysis provide evidence supporting that modifications in the average size is more relevant in hubs proteins than changes in the number of low-complexity regions.

Validação experimental de modelos matemáticos para a predição do volume e área superficial de ovos

Em razão da grande importância das características geométricas do ovo na agroindústria, objetivou-se, com o presente estudo, validar experimentalmente diversos modelos matemáticos do volume e área superficial de ovos, utilizando equações empíricas ajustadas e da literatura, visando a melhoria na precisão do cálculo destes parâmetros. Para isso, 450 amostras de ovos foram coletadas, sendo 150 ovos brancos, 150 ovos vermelhos e 150 ovos de codorna. Cada ovo foi pesado e suas dimensões (comprimento e largura) foram medidas utilizando um paquímetro digital. O volume real de cada ovo foi determinado pelo método de imersão em água. A área superficial, bem como o volume, das amostras foram obtidos por equações empíricas ajustadas, método computacional e por meio de equações da literatura. Com base nos resultados, os ovos vermelhos possuem peso, volume e área superficial estatisticamente maiores em relação os ovos brancos e de codorna (P

Violent suicidal behaviour in bipolar disorder is associated with nitric oxide synthase 3 gene polymorphism

OBJECTIVE

Given the importance of nitric oxide system in oxidative stress, inflammation, neurotransmission and cerebrovascular tone regulation, we postulated its potential dysfunction in bipolar disorder (BD) and suicide. By simultaneously analysing variants of three isoforms of nitric oxide synthase (NOS) genes, we explored interindividual genetic liability to suicidal behaviour in BD.

METHOD

A total of 536 patients with BD (DSM-IV) and 160 healthy controls were genotyped for functionally relevant NOS1, NOS2 and NOS3 polymorphisms. History of suicidal behaviour and violent suicide attempt was documented for 511 patients with BD. Chi-squared test was used to perform genetic association analyses and logistic regression to test for gene-gene interactions.

RESULTS

NOS3 rs1799983 T homozygous state was associated with violent suicide attempts (26.4% vs. 10.8%, in patients and controls, P = 0.002, corrected P (Pc) = 0.004, OR: 2.96, 95% CI = 1.33-6.34), and this association was restricted to the early-onset BD subgroup (37.9% vs. 10.8%, in early-onset BD and controls, P = 0.0003, Pc = 0.0006 OR: 5.05, 95% CI: 1.95-12.45), while we found no association with BD per se and no gene-gene interactions.

CONCLUSION

Our results bring further evidence for the potential involvement of endothelial NOS gene variants in susceptibility to suicidal behaviour. Future exploration of this pathway on larger cohort of suicidal behaviour is warranted.

Virtual Kitchen Test. Assessing frontal lobe functions in patients with alcohol dependence syndrome

INTRODUCTION

This article is part of the Focus Theme of Methods of Information in Medicine on "New Methodologies for Patients Rehabilitation".

BACKGROUND

The ecological validity of paper-and-pencil neuropsychological tests is currently a matter of debate. Arguments in favor of alternatives indicate that paper-and-pencil forms are unable to account for both mental and functional aspects of cognitive functioning.

OBJECTIVES

In this study we developed a new neuropsychological evaluation test - the Virtual Kitchen Test (VKT) - devised to evaluate frontal brain functioning in cognitively impaired individuals. We designed this test according to the rationale of the Trail Making Test (TMT), in order to capture frontal lobe abilities during a more ecologically valid task.

METHODS

Forty-nine participants, 25 from a clinical sample of patients diagnosed with Alcohol Dependence Syndrome, plus 24 healthy participants.

RESULTS

Execution errors and task completion time were significantly higher in the clinical sample. Also, scores on the new VKT showed moderate to high positive correlations with scores on the TMT. Furthermore, the overall discriminant performance of the VKT was high for both of its indicators.

CONCLUSIONS

Overall results support the ability of the VKT to evaluate frontal lobe functions. The best cut-off scores based on this sample are discussed.

The "psychomicrobiotic": Targeting microbiota in major psychiatric disorders: A systematic review

The gut microbiota is increasingly considered as a symbiotic partner in the maintenance of good health. Metagenomic approaches could help to discover how the complex gut microbial ecosystem participates in the control of the host's brain development and function, and could be relevant for future therapeutic developments, such as probiotics, prebiotics and nutritional approaches for psychiatric disorders. Previous reviews focused on the effects of microbiota on the central nervous system in in vitro and animal studies. The aim of the present review is to synthetize the current data on the association between microbiota dysbiosis and onset and/or maintenance of major psychiatric disorders, and to explore potential therapeutic opportunities targeting microbiota dysbiosis in psychiatric patients.