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Melani MS, Paiva JM, Mendlowicz MV, Vilete L, Luz MP, Ventura PR, Passos RBF, Berger W. Are There Differences Among Evidence-Based Psychotherapies for Treating Different DSM-5 PTSD Symptom Clusters? A Systematic Review and Meta-analysis of Controlled Clinical Trials. J Nerv Ment Dis 2024; 212:332-343. [PMID: 38810096 DOI: 10.1097/nmd.0000000000001769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
ABSTRACT Posttraumatic stress disorder (PTSD) is a heterogeneous disease defined by four Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) symptom clusters: reexperiencing, avoidance, negative alterations in cognitions and mood, and hyperarousal. There are effective evidence-based psychotherapies (EBPs) for PTSD. However, given the variety of PTSD clinical presentations, we conducted the first meta-analysis investigating whether DSM-5 PTSD symptom clusters show different responses to EBPs. We systematically reviewed the literature for controlled clinical trials in five databases, performed a meta-analysis, and evaluated the methodological quality of the studies. We screened 633 studies and included seven. Three showed high risk, two showed some concerns, and one showed a low risk of bias. The symptom clusters do not seem to respond differently to EBPs (SMD cluster B: -0.40; 95% confidence interval [CI], -0.87 to 0.08; cluster C: -0.49; 95% CI, -0.90 to -0.08; cluster D: -0.44; 95% CI, -0.94 to 0.05; cluster E: -0.54; 95% CI, -1.07 to -0.0), even when analyzed by the therapeutic focuses. The findings dovetail nicely with the network theory of PTSD symptom, as although it is a heterogeneous disorder, the EBPs seem to promote a kind of cascade of symptom improvement.
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da Silva HC, Vilete L, Coutinho ESF, Luz MP, Mendlowicz M, Portela CM, Figueira I, Ventura P, Mari JDJ, Quintana MI, Ribeiro WS, Andreoli SB, Berger W. The role of childhood cumulative trauma in the risk of lifetime PTSD: An epidemiological study. Psychiatry Res 2024; 336:115887. [PMID: 38642421 DOI: 10.1016/j.psychres.2024.115887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 03/11/2024] [Accepted: 03/29/2024] [Indexed: 04/22/2024]
Abstract
Cumulative trauma is usually devastating and can lead to severe psychological consequences, including posttraumatic stress disorder (PTSD). Exposure to various types of traumas, particularly during childhood, can be even more deleterious than the sheer number of events experienced. This epidemiological study is the first to investigate the impact of discrete childhood traumatic exposure on the risk of developing lifetime PTSD in a representative sample of the general population of the two biggest Brazilian cities. Participants were aged between 15 and 75 years old, living in São Paulo and Rio de Janeiro, Brazil, who had experienced traumatic events (N = 3,231). The PTSD diagnosis was assessed using the DSM-IV criteria through the version 2.1 of Composite International Diagnostic Interview. To operationalize childhood cumulative trauma, we considered the sum of 15 different childhood trauma categories that occurred before PTSD onset. The final multivariate logistic regression model indicated a strong relationship between the number of discrete types of childhood traumas and the likelihood of the lifetime PTSD development. The lifetime PTSD risk increased 28 % with each different type of childhood trauma when adjusted by confounds. Our study strengthens the evidence associating childhood cumulative trauma to increased lifetime PTSD risk.
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Paiva JM, Dos Santos Melani M, Marques ESN, Arcosy CV, Coutinho ESF, Ventura P, Berger W. The efficacy of internet-delivered cognitive-behavioral therapy for posttraumatic stress disorder according to the mean age of patients: a systematic review and meta-analysis. PSYCHOL HEALTH MED 2024; 29:683-697. [PMID: 38083873 DOI: 10.1080/13548506.2023.2292478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 12/04/2023] [Indexed: 03/26/2024]
Abstract
Internet-delivered cognitive-behavioral therapy (I-CBT) is effective in treating post-traumatic stress disorder (PTSD) symptoms, offering enhanced accessibility and cost-effectiveness. However, it's important to note that these technologies may not be suitable for all age groups. Therefore, we conducted a systematic review and meta-analysis to determine if the effectiveness of I-CBT in treating PTSD varies based on the patients' mean age. We conducted a systematic review of the literature, focusing on randomized controlled trials (RCTs) in the ISI Web of Science, PubMed/MEDLINE, and PsycINFO databases. Following this, we performed a meta-analysis and evaluated the risk of bias using the Cochrane risk of bias quality assessment tool. In this study, we examined patient-related factors (civil or military status, age, and gender), clinical characteristics (baseline PTSD severity and type of trauma), and treatment characteristics (type of intervention, synchronous or asynchronous delivery, and the number of sessions) as independent variables. The dependent variable was the reduction in mean PTSD symptoms. Five RCTs out of 1,552 screened studies were included in this review, all of which showed some level of concern regarding potential bias. Our meta-analysis indicates that I-CBT is equally effective regardless of patients' mean age. Since all RCTs included only provide the mean age of the patients, further randomized controlled trials should address the effectiveness of I-CBT among different age groups.
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Mendlowicz MV, Gekker M, Xavier Gomes de Araújo A, de Oliveira L, Pereira MG, Berger W, Pires da Luz M, Vilete LMP, Marques-Portella C, Figueira I, Reis da Silva Junior T. The top-100 cited articles on post-traumatic stress disorder: a historical bibliometric analysis. PSYCHOL HEALTH MED 2024; 29:453-472. [PMID: 36398923 DOI: 10.1080/13548506.2022.2147555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 10/31/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
Abstract
This is a bibliometric analysis of the most-cited articles on post-traumatic stress disorder (PTSD) with the objective of identifying citation patterns for researchers, journals, centers, periods, topics, and nations. A search was conducted in Thomson Reuters' WoS Core Collection employing the expression TI = (posttraumatic stress disorder OR post-traumatic stress disorder OR PTSD). The 100 most-cited articles were downloaded, and the relevant data were extracted and analyzed. These studies had a total of 69,649 citations, ranging from a minimum of 360 to a maximum of 6029 citations, with an average of 696.49, a standard deviation of 720.92, mode of 369, and a median of 512. Eighty-eight percent of the most-cited articles on PTSD originated from the USA, with just six cities accounting for 52% of the publications and the Boston area alone responsible for almost one-fifth of the total output. The universities of Yale and Harvard headed the ranking of institutions with larger numbers of highly-cited articles. Female researchers represented 42.3% of all authors, 51% of the first authors, and 48% of the corresponding authors. The proportion of M.D. authors decreased significantly between the 1980-1999 (42%) and the 2000-2019 (27.2%) periods while that of Ph.D. authors increased from 44% to 57.4%. The most studied population was military veterans (28%). Female victims of sexual or physical violence, traumatized children, and adult survivors of childhood abuse were assessed in only 6-7% of the most-cited publications. Ten clinical trials evaluated psychological interventions but only three investigated pharmacotherapy. We concluded that influential research on PTSD remains centralized in the USA. A balanced gender representation in publications was found. There was a heavy reliance on combat veterans as the study population. Few highly-cited studies on the pharmacotherapy for PTSD were identified. Focused efforts are needed to address these challenges.
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Von Arcosy C, Padilha M, Mello GL, Vilete L, Luz MP, Mendlowicz M, Serpa OD, Berger W. A bright side of adversity? A systematic review on posttraumatic growth among refugees. Stress Health 2023; 39:956-976. [PMID: 36949033 DOI: 10.1002/smi.3242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 02/26/2023] [Accepted: 03/08/2023] [Indexed: 03/24/2023]
Abstract
Until the third trimester of 2022, 103 million people worldwide had been forced to leave their homes and become refugees. The traumatic experiences of refugees can lead not only to mental disorders but also to Posttraumatic Growth (PTG). (1) To find the variables positively and negatively associated with PTG in refugees. (2) To investigate the relationship between PTG and Posttraumatic Stress Disorder (PTSD) among refugees. We systematically searched Medline, Web of Knowledge, PsycInfo, Scopus, and PTSD Pubs for studies about PTG in refugees. Epidemiological studies using the Posttraumatic Growth Inventory. Grey literature, reviews, and meta-analysis. Risk of bias was assessed by the 'The Joanna Briggs Institute Prevalence Critical Appraisal Tool'. We included 24 studies investigating PTG and associated factors. The factors positively associated with PTG were social support, regular migration status, religiosity, satisfaction with life, time, and problem-focussed and emotion-focussed coping. The factors negatively associated with PTG were: irregular migration status, emotional suppression, and avoidance coping. Studies on PTG in refugees are essential to finding new ways to address mental health in this field. Few studies offered risk of bias, particularly regarding the sample selection. We conclude that PTG may be influenced by many factors and it would be of importance that the centres for support, as well as public policies, took that into account to foster the outcome and not only to focus on disease. This study was partially supported by CAPES and registered on PROSPERO (CRD42020215607).
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Portugal LCL, Ramos TC, Fernandes O, Bastos AF, Campos B, Mendlowicz MV, da Luz M, Portella C, Berger W, Volchan E, David IA, Erthal F, Pereira MG, de Oliveira L. Machine learning applied to fMRI patterns of brain activation in response to mutilation pictures predicts PTSD symptoms. BMC Psychiatry 2023; 23:719. [PMID: 37798693 PMCID: PMC10552290 DOI: 10.1186/s12888-023-05220-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 09/25/2023] [Indexed: 10/07/2023] Open
Abstract
BACKGROUND The present study aimed to apply multivariate pattern recognition methods to predict posttraumatic stress symptoms from whole-brain activation patterns during two contexts where the aversiveness of unpleasant pictures was manipulated by the presence or absence of safety cues. METHODS Trauma-exposed participants were presented with neutral and mutilation pictures during functional magnetic resonance imaging (fMRI) collection. Before the presentation of pictures, a text informed the subjects that the pictures were fictitious ("safe context") or real-life scenes ("real context"). We trained machine learning regression models (Gaussian process regression (GPR)) to predict PTSD symptoms in real and safe contexts. RESULTS The GPR model could predict PTSD symptoms from brain responses to mutilation pictures in the real context but not in the safe context. The brain regions with the highest contribution to the model were the occipito-parietal regions, including the superior parietal gyrus, inferior parietal gyrus, and supramarginal gyrus. Additional analysis showed that GPR regression models accurately predicted clusters of PTSD symptoms, nominal intrusion, avoidance, and alterations in cognition. As expected, we obtained very similar results as those obtained in a model predicting PTSD total symptoms. CONCLUSION This study is the first to show that machine learning applied to fMRI data collected in an aversive context can predict not only PTSD total symptoms but also clusters of PTSD symptoms in a more aversive context. Furthermore, this approach was able to identify potential biomarkers for PTSD, especially in occipitoparietal regions.
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Mendlowicz V, Garcia-Rosa ML, Gekker M, Wermelinger L, Berger W, Luz MPD, Pires-Dias PRT, Marques-Portela C, Figueira I, Mendlowicz MV. Post-traumatic stress disorder as a predictor for incident hypertension: a 3-year retrospective cohort study. Psychol Med 2023; 53:132-139. [PMID: 33849680 DOI: 10.1017/s0033291721001227] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND The goal of the present study was to investigate the association between PTSD and the onset of hypertension in previously normotensive individuals in a population living in the stressful environment of the urban slums while controlling for risk factors for cardiovascular disease (CVD). METHODS Participants were 320 normotensive individuals who lived in slums and were attending a family doctor program. Measurements included a questionnaire covering sociodemographic characteristics, clinical status and life habits, the Posttraumatic Stress Disorder Checklist - Civilian Version, and the Beck Depression Inventory. Incident hypertension was defined as the first occurrence at the follow-up review of the medical records of (1) systolic blood pressure of 140 mm Hg or higher or diastolic blood pressure of 90 mm Hg or higher, (2) the participant started taking antihypertensive medication, or (3) a new diagnosis of hypertension made by a physician. Differences in sociodemographic, clinical, and lifestyle characteristics between hypertensive and non-hypertensive individuals were compared using the χ2 and t tests. Multivariate Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). RESULTS Six variables - age, educational level, body mass, smoking, diabetes, and PTSD diagnosis - showed a statistically significant (p ≤ 0.20) association with the hypertensive status. In the Cox regression, only PTSD diagnosis was significantly associated with incident hypertension (multivariate HR = 1.94; 95% CI 1.11-3.40). CONCLUSIONS The present findings highlight the importance of considering a diagnostic hypothesis of PTSD in the prevention and treatment of cardiovascular diseases.
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Zakhour S, Sardinha A, Levitan M, Berger W, Nardi AE. Instruments for assessing sexual dysfunction in Arabic: A systematic literature review. Transcult Psychiatry 2022; 59:819-830. [PMID: 35818838 DOI: 10.1177/13634615221105120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Sexual health is relevant throughout a person's life; however, studying human sexuality is complex and requires particular care when working with individuals from different cultural and social backgrounds. Much of the research addressing this subject has been conducted in Western countries, and that in non-Western countries is generally based on small sample sizes. The biopsychosocial nature of sexuality and its dysfunctions should be taken into consideration given that it is indispensable when conducting and assessing sexual studies in different countries and cultures. Therefore, culturally sensitive studies that consider cultural contexts and determinants as well as social markers are needed. The topic of sexuality in Arab culture is still enigmatic. This enigma has impacted the advancement of sexual science and limited researchers, health care practitioners, and patients. Thus, the aim of this systematic literature review was to find and assemble all scales and questionnaires regarding human sexual health that have been translated into Arabic and validated in order to promote a critical analysis of the methods used in each instrument and to inform readers and researchers of the limits and potential of each scale. Electronic databases were systematically searched, and eight instruments were selected for inclusion: the Arabic Index of Premature Ejaculation (AIPE), the Sexual Health Inventory for Men (SHIM), the Arabic Female Sexual Function Index (ArFSFI), the Female Genital Self-Image Scale (AVFGSIS), the Arabic Arizona Sexual Experiences Scale (ASEX), the Egyptian Pelvic Organ Prolapse/Incontinence Sexual Questionnaire (PISQ-IR), the Saudi Arabian Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire in Arabic (PSIQ-IR), and the Arabic Female Sexual Distress Scale (FSDS). All included instruments showed good validity and reliability for the target population. Future studies are needed to develop culturally sensitive instruments.
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Reis T, Gekker M, Land MGP, Mendlowicz MV, Berger W, Luz MP, Vilete L, Figueira I, Araújo AXG. The growth and development of research on personality disorders: A bibliometric study. Personal Ment Health 2022; 16:290-299. [PMID: 35182026 DOI: 10.1002/pmh.1540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/19/2022] [Accepted: 02/08/2022] [Indexed: 01/31/2023]
Abstract
This study objective was to investigate publication trends on personality disorders (PD) and to identify patterns of historical development. Publication rates were determined using the Results by Year Timeline feature of PubMed. Time series autoregressive integrated moving average models were used to analyse the publication rates for PDs in quinquennial periods beginning in 1980 and ending in 2019 and to predict the number of publications in the 2024-2029 period. More than 300 articles on antisocial and borderline PD are being published each year, and the models suggest an accelerating growth rate. Approximately 100 articles are being published on average every year on schizotypal PD, and the regression model indicates linear growth in the near future. The mean number of publications per year for obsessive-compulsive, narcissistic and avoidant PDs is in the range of 10-30 with the corresponding models indicating linear growth. Fewer than 10 articles are being published each year on dependent, paranoid, histrionic and schizoid PD, whereas dependent PD shows modest growth and paranoid PD rates tended to stability, histrionic and schizoid PD exhibit declining rates. Personality disorders are a group of conditions with diverse etiological, prognostic, therapeutic, legal, research, social and cultural implications that influence publication rates.
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Kalaf J, Freire Coutinho ES, Mendlowicz M, Marques Portella C, Berger W, Pires Luz M, Volchan E, Rui Ventura P, Nascimento Júdice M, Alvarenga Flavio Blanco S, Meirelles Paiva J, Figueira I. STUCK IN A MOMENT: TONIC IMMOBILITY PREDICTS POOR QUALITY OF LIFE IN TREATED PTSD PATIENTS. PSYCHIATRIA DANUBINA 2022; 34:447-454. [DOI: 10.24869/psyd.2022.447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Machado AV, Gonçalves RM, Gama CMF, Vilete LMP, Berger W, Passos RBF, Mendlowicz MV, Souza GGL, Pereira MG, Mocaiber I, de Oliveira L. The different impacts of COVID-19 on the mental health of distinct health care worker categories. J Health Psychol 2022; 28:434-449. [PMID: 36113021 PMCID: PMC10076179 DOI: 10.1177/13591053221120968] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The present study sought to explore the factors associated with the odds of having probable depression and posttraumatic stress disorder (PTSD) related to traumatic COVID-19 experiences and their impact on health care workers in distinct categories. In this cross-sectional study, 1843 health care workers (nurses, nurse technicians, physicians, physical therapists, and other healthcare workers) were recruited via convenience sampling. A survey was administered to obtain information regarding sociodemographic, occupational, and mental health status. Descriptive statistics and multivariable logistic regression were used for the analyses. Being a nurse technician was associated with an odds ratio of 1.76 for probable PTSD. No relation was observed between health care worker categories and the odds of probable depression. Additionally, being female and not receiving adequate PPE were related to greater odds of having probable PTSD and depression.
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Neumayer K, Kastler L, Laaber M, Roschger C, Lenz S, Lötsch-Gojo D, Berger W, Gruber A, Spiegl-Kreinecker S. P18.06.B ETS-Transcription Factor inhibitors are effective in TERT promoter mutated meningioma cells in vitro. Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac174.333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
TERT promoter mutations in meningiomas were recently found to be strongly prognostic and associated with malignant progression and risk of recurrence. As result, the mutation in the TERT promoter generates a binding site for E twenty-six (ETS) transcription factors. Consequently, ETS-transcription factor inhibition might represent a novel strategy to impede meningioma growth. In a prior study we could demonstrate effectiveness of the ETS-transcription factor inhibitor YK-4-279 in TERT promoter mutant meningiomas. Recently, TK216 the clinical derivative of YK-4-279 was developed. Therefore, we aimed to clarify whether TK216 might have an increased effect as compared to YK-4-279 in TERT promoter mutated meningioma cells in vitro.
Methods
A meningioma-derived cell line (BTL695) generated from a TERT promoter mutated (C228T) anaplastic meningioma served as cell model for the experiments. BTL695 was characterized by high telomerase activity and TERT mRNA expression as analysed by the TRAP assay and RT-PCR, respectively. Genomic aberrations were verified using Ion Torrent Oncomine Comprehensive Assay v3-based next-generation sequencing (NGS). The sensitivity of BTL695 to YK-4-279 and TK216 was determined using an MTT-based viability assay (EZ4U). To elucidate the effectiveness of TK216 on cell cycle and apoptosis, cells were stained with PI and annexin V, respectively, and measured by flow cytometry. The effect of TK216 on the protein expression of the cleaved poly(ADP-ribose) polymerase-1 (PARP-1), indicative for apoptosis, was investigated by western blot. Additionally, a TK216-resistant cell model (BTL695res) was generated and analysed by NGS.
Results
BTL695 was significantly more sensitive to TK216 as compared to YK-4-279 (p<0.0001) characterized by the distinctly lower IC50 value of TK216 exposed cells (0.7 µM TK216; 1.6 µM YK-4-279). Flow cytometry analysis revealed a TK216 induced G2M cell cycle arrest and increased apoptosis rate, which was additionally verified by the expression of cleaved PARP-1 expression using western blot. Genomic aberrations were found in 18 genes including NF2, CDKN2A/B, ARID1A and PTEN. Interestingly, although the majority of genomic alterations was persistent in the TK216 resistant cell model, a p53 mutation was newly acquired as compared to the parental cell line.
Conclusion
In summary, our results indicate that ETS transcription factor inhibition by TK216 exerts antitumour activity in our TERT promoter mutant meningioma cell model. Additionally, the sensitivity against TK216 is superior to YK-4-279 and therefore TK216 may represent a promising new therapeutic option for patients with aggressive, TERT promoter mutated meningioma.
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Mischkulnig M, Roetzer-Pejrimovsky T, Lötsch-Gojo D, Kastner N, Bruckner K, Prihoda R, Lang A, Martinez-Moreno M, Furtner J, Berghoff A, Woehrer A, Berger W, Widhalm G, Kiesel B. P07.04.B Heme biosynthesis factors and 5-ALA induced fluorescence: analysis of mRNA and protein expression in fluorescing and non-fluorescing gliomas. Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac174.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
The intraoperative visualization of adult-type diffuse gliomas with 5-aminolevulinic acid (5-ALA) induced fluorescence is widely used in the neurosurgical field. While visible 5-ALA induced fluorescence is found in the majority of high-grade gliomas, most low-grade gliomas lack visible fluorescence during surgery. Recently, the heme biosynthesis pathway was identified as crucial influencing factor for presence of visible fluorescence since it metabolizes 5-ALA to fluorescing Protoporphyrin IX (PpIX). However, the exact alterations within the heme biosynthesis pathway resulting in visible 5-ALA induced fluorescence in gliomas are still unclear. The aim of the present study was thus to compare the mRNA and protein expression of promising intramitochondrial heme biosynthesis enzymes/transporters in glioma tissue samples of different fluorescence behavior.
Material and Methods
A total of 19 strongly fluorescing and 21 non-fluorescing tissue samples from neurosurgical adult-type diffuse gliomas (WHO grades II-IV) were included in the current analysis. In these samples, we investigated the mRNA expression by quantitative real time PCR and protein expression using immunohistochemistry of the intramitochondrial heme biosynthesis enzymes Coproporphyrinogen Oxidase (CPOX), Protoporphyrinogen Oxidase (PPOX), Ferrochelatase (FECH) and the transporter ATP-binding Cassette Subfamily B Member 2 (ABCG2).
Results
Regarding mRNA expression analysis, we found a significantly decreased ABCG2 expression in fluorescing specimens compared to non-fluorescing samples (p=0.001), whereas no difference in CPOX, PPOX and FECH was present. With respect to protein expression, significantly higher levels of CPOX (p=0.005), PPOX (p<0.01) and FECH (p=0.003) were detected in fluorescing samples. Similar to mRNA expression analysis, the protein expression of ABCG2 (p=0.001) was significantly lower in fluorescing samples.
Conclusion
Distinct alterations of the analyzed heme biosynthesis factors were found primarily on protein level. Our data indicate that heme biosynthesis pathway activity in general is enhanced in fluorescing gliomas with upregulation of PpIX generating enzymes and decreased ABCG2 mediated PpIX efflux outweighing the also increased further metabolization of PpIX to heme. Intramitochondrial heme biosynthesis factors thus constitute promising pharmacological targets to optimize intraoperative 5-ALA fluorescence visualization of usually non-fluorescing tumors such as low-grade gliomas.
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Kastler L, Neumayer K, Laaber M, Roschger C, Lenz S, Lötsch-Gojo D, Berger W, Gruber A, Spiegl-Kreinecker S. P10.08.A Lipogenesis inhibition by fatostatin shows effectiveness in glioblastoma models highly expressing fatty acid synthase (FASN). Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac174.173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Glioblastoma (GBM) is the most common and most aggressive primary brain tumour in adults. Despite intensive treatment, the medium overall survival of GBM patients remains below 20 months after diagnosis. Therefore, new tumour specific targets allowing successful therapeutic treatment are needed to distinctly enhance GBM patient overall survival. Reprogramming of lipid metabolism leading to highly upregulated anabolic pathways, like phosphatidylinositol-3-kinase (PI3K)/AKT pathway and subsequently lipogenesis, is a hallmark of cancer cells including glioblastomas to meet increased energy demands for proliferation and cell growth. Accordingly, lipogenesis inhibition might be a promising strategy to impede GBM cell growth. Therefore, it was aim of our study to analyse the effect of the lipogenesis inhibitor fatostatin on downstream targets e.g. fatty acid synthase (FASN) and its impact on cell growth in GBM cells in vitro.
Material and Methods
In a cohort of 52 GBM-derived cell lines, FASN mRNA was investigated by qRT-PCR. The impact of fatostatin on cell viability (IC50) was analysed in selected cell lines using cell viability assays (Cell Titer Glo®). To elucidate whether fatostatin exposure affects cell migration, wound healing assays were performed. The effect of fatostatin on cell cycle and apoptosis was analysed by flow cytometry. Additionally, expression of FASN and level of phosphorylated AKT, the active form of AKT serine/threonine kinase, were examined before and after fatostatin treatment with qRT-PCR (mRNA) and Western blot (protein), respectively.
Results
FASN mRNA was found to be expressed at varying levels in our GBM-derived cell line cohort (n=52). Compared to normal astrocytes, FASN mRNA expression was significantly upregulated in GBM cells (p=0.0127). Furthermore, high FASN mRNA expression was significantly associated with higher sensitivity against fatostatin (p=0.0352). Regarding corresponding recurrences, the response to the inhibitor was shown to be persistent. Accordingly, the effectiveness of fatostatin treatment resulted in substantial downregulation of AKT phosphorylation and consequently in the induction of apoptosis and G2/M arrest of the cell cycle. In addition, a significant inhibition of the migration potential by fatostatin treatment was observed.
Conclusion
In summary, FASN expression represents a promising biomarker and therapy target within the lipid metabolism indicated by a significant sensitivity to fatostatin in FASN overexpressing GBM cell lines. Consequently, lipogenesis inhibition by fatostatin might be a promising novel therapeutic option in glioblastoma.
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Ries A, Flehberger D, Schelch K, Pirker C, Hoda M, Berger W, Grusch M. EP07.01-014 Mesothelioma-Associated Fibroblasts Enhance Mesothelioma Aggressiveness and Modulate Drug Response. J Thorac Oncol 2022. [DOI: 10.1016/j.jtho.2022.07.546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gama CMF, de Souza Junior S, Gonçalves RM, Santos EDC, Machado AV, Portugal LCL, Passos RBF, Erthal FS, Vilete LMP, Mendlowicz MV, Berger W, Volchan E, de Oliveira L, Pereira MG. Tonic immobility is associated with posttraumatic stress symptoms in healthcare professionals exposed to COVID-19-related trauma. J Anxiety Disord 2022; 90:102604. [PMID: 35917747 PMCID: PMC9272678 DOI: 10.1016/j.janxdis.2022.102604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 07/01/2022] [Accepted: 07/04/2022] [Indexed: 11/16/2022]
Abstract
The Coronavirus Disease 2019 (COVID-19) pandemic has exposed healthcare workers (HCW) to traumatic situations that might lead to the development of posttraumatic stress disorder (PTSD). An important vulnerability factor for PTSD is the peritraumatic tonic immobility (TI) reaction, an involuntary and reflexive defensive response evoked by an intense and inescapable threat. TI is largely understudied in humans and has not been investigated during trauma related to COVID-19. For HCW, the pandemic context might be experienced as an intense and potentially inescapable threat, i.e., an overwhelming situation. Here, we investigated if TI response occurred during traumatic events related to the pandemic and its association with posttraumatic stress symptoms (PTSS). An online survey of 1001 HCW investigated COVID-19-related traumatic experiences, TI and PTSS. TI was reported for all types of traumatic events, and multivariate regression models revealed that TI was significantly associated with PTSS severity. HCW who reported high TI scores exhibited an increase of 9.08 times the probability of having a probable diagnosis of PTSD. Thus, TI was evoked by pandemic-related traumatic situations and associated with PTSS severity and higher odds of a PTSD diagnosis. Tonic immobility occurrence should be screened, and psychoeducation about its reflexive biological nature should be introduced.
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Paiva J, Melani M, Gonçalves RM, Luz MP, Mendlowicz MV, Figueira I, von Arcosy C, Ventura P, Berger W. Predictors of response to cognitive-behavioral therapy in patients with posttraumatic stress disorder: a systematic review. JORNAL BRASILEIRO DE PSIQUIATRIA 2022. [DOI: 10.1590/0047-2085000000375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ABSTRACT Objective Posttraumatic stress disorder (PTSD) is a highly prevalent and disabling disorder. Even when treated with the first-line intervention, cognitive-behavioral therapy (CBT), 45% of the patients continue suffering from this disorder. Therefore, knowing the factors that could foresee who will respond to CBT would be of great value to the treatment of these patients. Thus, we have systematically reviewed the literature to identify the variables that could predict response to CBT in patients suffering from PTSD. Methods Following the PRISMA 2020 guidelines, we searched the electronic databases ISI Web of Science, Scopus, PsycINFO, MEDLINE, and PTSDpubs until November 2021. Two authors have independently conducted study selection and data extraction. Studies that examined possible predictors of response to therapy on a sample of adults (18-65 years), both genders, with and without comorbidities were considered eligible. The characteristics of the studies were synthesized in a table. The risk of bias was assessed by the Cochrane risk of bias quality assessment tool. Results Twenty-eight studies comprising 15 variables were selected. Among those, eight showed a low risk of bias, 19 showed some concerns, and one showed a high potential risk of bias. The therapeutic relationship was the only variable considered to be a predictor of a good response to therapy. All other variables showed conflicting results. Conclusions The most promising variable, although scientifically weak, is the therapeutic relationship. Additional randomized clinical trials should be conducted to clarify the role of this variable as a predictor of response to CBT in patients with PTSD.
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Campos B, Vinder V, Passos RBF, Coutinho ESF, Vieira NCP, Leal KB, Mendlowicz MV, Figueira I, Luz MP, Marques-Portela C, Vilete LMP, Berger W. To BDZ or not to BDZ? That is the question! Is there reliable scientific evidence for or against using benzodiazepines in the aftermath of potentially traumatic events for the prevention of PTSD? A systematic review and meta-analysis. J Psychopharmacol 2022; 36:449-459. [PMID: 35437077 DOI: 10.1177/02698811221080464] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Most international guidelines suggest that benzodiazepines (BDZs) may be inefficient or iatrogenic in the aftermath of a potentially traumatic event (PTE). The goal of this study was to assess the strength of the evidence on whether the use of BDZs in the aftermath of a PTE negatively affects the incidence and severity of post-traumatic stress disorder (PTSD). METHODS We systematically scrutinized the ISI Web of Knowledge, MEDLINE, SCOPUS, and PTSDpubs electronic databases in addition to citation searching. We included original studies providing data about the development of PTSD in adults after BDZ administration in the aftermath of a PTE. We screened 387 abstracts and selected eight studies for the qualitative synthesis and seven for the meta-analysis. We performed two separate meta-analyses, one for randomized clinical trials (RCTs) and the other for cohort studies. Heterogeneity between studies was evaluated with Higgins I² statistic and tested using the χ². This study was registered at PROSPERO (number 127170). RESULTS The meta-analysis of the cohort studies showed an increased risk of PTSD in patients who received BDZs compared to those who did not (risk ratio (RR) = 1.53; 95% confidence interval (CI): 1.05-2.23) with a modest heterogeneity among studies (I2 = 41.8, p = 0.143). Regarding the RCTs, the combined measure revealed a tendency toward an increased severity of the PTSD symptoms (standardized mean difference (SMD): 0.24; 95% CI: 0.32-0.79). CONCLUSION The studies reviewed showed a possible harmful effect of BDZs when used immediately after a PTE. However, these conclusions were based on a small number of studies of poor to moderate methodological quality.
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Sipe JM, Bossa N, Berger W, von Windheim N, Gall K, Wiesner MR. From bottle to microplastics: Can we estimate how our plastic products are breaking down? THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 814:152460. [PMID: 34973311 DOI: 10.1016/j.scitotenv.2021.152460] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/09/2021] [Accepted: 12/12/2021] [Indexed: 05/14/2023]
Abstract
Microplastics (MPs) have become an emerging new pollutant of rising concern due to the exponential growth of plastics in consumer products. Most MP and nanoplastic pollution comes from the fragmentation of plastics through mechanical stress, chemical reactions and biological degradation that occurs during use and after disposal. Models predicting the generation and behavior of MP in the environment are developing, however there is lack of data to predict the rates of MP generation as a function of the abrasive forces. A method to deliver scalable, quantitative release rates of MPs during mechanical stress throughout a plastic's life cycle (e.g., sanding, chewing, river and ocean disposal) is described. A custom abrasion machine was built with features to provide data to calculate power input. The generation rate of MPs through abrasion was tested for the following 3D printed polymers: polylactic acid (PLA), polycarbonate (PC), thermoplastic polyurethane 85A (TPU), polyethylene glycol terephthalate (PETG), high-impact polystyrene (HIPS), and nylon. Each material underwent tensile strength material tests to identify which mechanical properties drive their abrasion rate. Abrasion rate was not observed to correlate to macroscopic mechanic properties. Results indicate that the order of abrasion from most to least were HIPS, nylon, PC, PLA, PETG, and then TPU. This study will help comprehend and provide data to understand generation rates of MPs from consumer plastic products and macro-plastic debris. This will be instrumental in helping to better understand the release of MPs and nanoplastics into the environment and to provide data for fate and transport models, especially in order to predict the amount of plastic entering water systems. MP generation rates and power inputs can be correlated with each plastic's use to inform which release the most MPs and how to better change these products in order to reduce pollution in water sources.
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Cosentino A, Odorizzi G, Berger W. Infected hip prosthesis in patient with suspected Covid-19 infection. ARTHROPLASTY 2022; 3:3. [PMID: 34977465 PMCID: PMC7850715 DOI: 10.1186/s42836-020-00058-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 12/14/2020] [Indexed: 11/23/2022] Open
Abstract
Background Infections following arthroplasty are one of the major risks during this type of surgery. Moreover, the outbreak of coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus Disease 2), has developed into an unprecedented pandemic, posing enormous pressure on health-care providers around the world. Case presentation Four and half years after right hip arthroplasty, the patient came back to our attention with pain at the same hip. The instrumental examinations showed signs of cup detachment. After carefully analyzing the case, we decided to perform a sterile aspiration of the hip in the operating room under C-arm fluoroscopy. Microbiological examinations showed positivity for E. coli. The patient underwent surgery by which the prosthesis was removed and a spacer was implanted. A therapy with Cefotaxim 2 g three times a day for 6 weeks was then set, and then a total arthroplasty was performed. During this period, the COVID-19 pandemic occurred and therefore the patient received nasal-throat swabbing two times, and both yielded negative results. However, 1 week after the final surgery, his respiratory conditions deteriorated and chest X-ray and CT scan showed images of ground-glass opacification patterns (GGO). Due to the clinical symptoms and the characteristic images of the instrumental examinations, the patient was transferred to an observation ward. Thereafter, two more swab tests gave negative results. The patient was then transferred to the ward for patients with typical symptoms of COVID-19 but with negative swab tests for 2 weeks and was subsequently discharged home. Conclusion The purpose of this case report was to point out the correct treatment of a PJI after the outbreak of COVID-19. Despite the ongoing COVID-19 pandemic, the guidelines in the case of periprosthetic hip infection further confirmed the correct management of the patient.
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Blaiss M, Berger W, Chipps B, Hernandez-Trujillo V, Phipatanakul W, Steward K. Review of efficacy of ciclesonide for the treatment of asthma in children. Allergy Asthma Proc 2021; 42:461-470. [PMID: 34871153 DOI: 10.2500/aap.2021.42.210062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Background: Ciclesonide (CIC) is an inhaled corticosteroid (ICS) approved for the maintenance treatment of asthma in patients ages ≥ 12 years. The prodrug aspect of CIC is associated with a safety profile that may make it ideal for children. Objective: The objective was to summarize efficacy results from the eight phase III, randomized, double-blind, controlled trials in children with asthma conducted during CIC clinical development. Methods: Four trials compared CIC 40, 80, or 160 µg/day with placebo. Two trials compared CIC 160 µg/day with fluticasone propionate 200 µg/day, one trial compared CIC 80 or 160 µg/day with fluticasone 200 µg/day, and one trial compared CIC 160 µg/day with budesonide 400 µg/day. Results: The primary end point was met by at least two CIC doses versus placebo in the trials in which the primary end point was the change from baseline in lung function outcome (forced expiratory volume in 1 second [FEV1] % predicted or morning peak expiratory flow [PEF]). A trial that compared CIC with placebo did not meet the primary end point of superiority in time-to-first severe wheeze exacerbation or lack of improvement. The primary end point of noninferiority to the active control (fluticasone or budesonide) in the change from baseline in a lung function outcome (FEV1, morning PEF, evening PEF) was met with the CIC 160-µg dose in all active control trials. CIC generally demonstrated statistically significant improvements in forced expiratory flow at 25%-75% of forced vital capacity, asthma symptoms, rescue medication use, and asthma control when compared with placebo and noninferiority for these outcomes compared with fluticasone or budesonide. Conclusion: In children with asthma, once-daily CIC significantly improved large and small airway function, asthma symptoms, and asthma control, and reduced rescue medication use compared with placebo. CIC was comparable with other ICS used to treat asthma in children, which demonstrated its worth for the pediatric population.
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Blaiss M, Berger W, Chipps B, Hernandez-Trujillo V, Phipatanakul W, Steward K. Safety of ciclesonide in children with asthma: A review of randomized controlled trials. Allergy Asthma Proc 2021; 42:471-480. [PMID: 34871154 DOI: 10.2500/aap.2021.42.210085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Background: Parental concerns about the adverse effects of asthma medications can lead to nonadherence and uncontrolled asthma in children. Ciclesonide (CIC) is a prodrug, with low oropharyngeal deposition and bioavailability that may minimize the risk of local and systemic adverse effects. CIC is U.S. Food and Drug Administration approved for asthma in children ages ≥ 12 years. Objective: To summarize safety results from the 13 phase II or III randomized controlled trials conducted in children with asthma during CIC clinical development. Methods: Four 12- to 24-week trials compared the safety of once-daily CIC 40, 80, or 160 µg/day with placebo; four 12-week trials compared the safety of CIC 80 or 160 µg/day with either fluticasone or budesonide; one 12-month trial compared the long-term safety of CIC 40, 80, or 160 µg/day with fluticasone; one 12-month trial compared growth velocity of CIC 40 or 160 µg/day with placebo; and three cross-over trials compared short-term growth velocity and hypothalamic-pituitary-adrenal (HPA) axis effects of CIC 40, 80, or 160 µg/day with placebo or fluticasone. Results: In all, 4399 children were treated with CIC. The incidence of treatment-emergent adverse events (AE) was similar among the CIC doses and between CIC and placebo in short-term studies and between CIC and fluticasone in the long-term safety study. No CIC-related serious AEs were reported in any study. The incidence of treatment-related oral candidiasis was low and similar between CIC (≤0.5%) and placebo (≤0.7%) or active controls (≤0.5%) in the short-term studies. There was no clinically relevant HPA axis suppression or reduction in growth velocity associated with CIC. Conclusion: Data from 13 studies demonstrate that CIC is associated with low rates of oropharyngeal AEs, with no indication of clinically relevant systemic effects in children with asthma. The favorable safety profile and demonstrated improvements in asthma control make CIC an ideal inhaled corticosteroid for the treatment of asthma in children.
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Magalhaes AA, Gama CMF, Gonçalves RM, Portugal LCL, David IA, Serpeloni F, Wernersbach Pinto L, Assis SG, Avanci JQ, Volchan E, Figueira I, Vilete LMP, Luz MP, Berger W, Erthal FS, Mendlowicz MV, Mocaiber I, Pereira MG, de Oliveira L. Tonic Immobility is Associated with PTSD Symptoms in Traumatized Adolescents. Psychol Res Behav Manag 2021; 14:1359-1369. [PMID: 34512046 PMCID: PMC8420784 DOI: 10.2147/prbm.s317343] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 08/11/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose Growing evidence suggests that peritraumatic tonic immobility, an involuntary defensive response that involves extreme physical immobility and the perceived inability to escape, is a significant predictor of post-traumatic stress disorder (PTSD) symptomatology. However, this issue has not been specifically addressed in adolescents. Here, we investigated whether tonic immobility response experienced during the worst childhood or adolescent trauma is associated with PTSD symptom severity in a non-clinical student sample. Methods The sample was composed of students in 9th grade who were attending public and private schools. Symptoms of post-traumatic stress and tonic immobility were assessed using questionnaires. We performed bivariate and multivariate negative binomial regressions to examine whether tonic immobility was associated with PTSD symptomatology after controlling for confounders (peritraumatic dissociation, peritraumatic panic reactions, gender, age and time since trauma). Results We found an association between tonic immobility and PTSD symptom severity, even after controlling for confounders. Therefore, tonic immobility is associated with PTSD symptoms in trauma-exposed adolescents. Conclusion These findings highlight tonic immobility as a possible risk factor that could be used to provide direction for more targeted trauma interventions for individuals, particularly those at risk for developing PTSD. Therefore, it contributes to preventing and reducing the psychiatric burden in adolescence and later in life.
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Oliveira RD, Mendlowicz MV, Berger W, Luz MPD, Marques-Portella C, Figueira I, Araújo AXGD. Unnecessarily prolonged suffering: a case of missed diagnosis of post-traumatic stress disorder in a teaching hospital. JORNAL BRASILEIRO DE PSIQUIATRIA 2021. [DOI: 10.1590/0047-2085000000323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ABSTRACT We described a case in which a heavily-traumatized patient had been under psychiatric treatment for seven years (five of them in a university mental health clinic) but was never diagnosed with PTSD and, therefore, did not receive the proper treatment for a very long period. After the correct diagnosis was made and personalized treatment instituted, the patient has shown marked improvement in functionality and wellbeing. The key element in this case, was the adequacy of psychiatric training. Our report suggests that psychiatrists are not being adequately trained to identify traumatic events and to diagnose atypical cases of PTSD. With that in mind, we emphasize that theoretical modules on trauma and trauma-related disorders and practical training in specialized PTSD clinics should be incorporated into the psychiatric residency training programs wherever they may be missing, particularly in countries most impacted by violence. Furthermore, continuing medical education on trauma and PTSD should be provided by medical associations and journals to keep physicians updated on recent progress in the field.
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Bossa N, Sipe JM, Berger W, Scott K, Kennedy A, Thomas T, Hendren CO, Wiesner MR. Quantifying Mechanical Abrasion of MWCNT Nanocomposites Used in 3D Printing: Influence of CNT Content on Abrasion Products and Rate of Microplastic Production. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10332-10342. [PMID: 34264058 PMCID: PMC10084403 DOI: 10.1021/acs.est.0c02015] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Manufactured nanomaterials (MNMs) are incorporated as "nanofillers" into consumer products to enhance properties of interest. Multiwalled carbon nanotubes (MWCNTs) are known for their unique properties and have many applications in polymers. However, the release of MWCNTs during the nanoenabled product life cycle is concerning. During the use phase, mechanical stresses can produce fragmented materials containing MNMs. The degree of MNM release, the resulting exposure to these materials, and the potential impacts of their release are active research topics. In this study, we describe methodological improvements to study the abrasion of plastics containing MNMs (nanocomposites) and report on characteristics of abrasion products produced and rates of microplastic production. The abrasion device developed for this work allows for the measurement of power inputs to determine scaled release rates. Abrasion rates for plastics used in 3D printing were found to be 0.27 g/m2/s for the PETG polymer and 0.3 g/m2/s for the 2% MWCNT-PETG nanocomposite. Embedded and protuberant MWCNTs appeared to impact the particle size, shape, hydrophobicity, and surface charge of the microplastics, while the inclusion of MWCNTs had a small effect on microplastic production. Measurements of power input to the abrasion process provided a basis for estimating microplastic production rates for these nanocomposites.
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