RESUMEN
Small GTPases of the Rab family coordinate multiple membrane fusion and trafficking events in eukaryotes. In fungi, the Rab GTPase, Ypt7, plays a critical role in late endosomal trafficking, and is required for homotypic fusion events in vacuole biogenesis and inheritance. In this study, we identified a putative YPT7 homologue in Cryptococcus neoformans, a fungal pathogen causing life threatening meningoencephalitis in immunocompromised individuals. As part of an ongoing effort to understand mechanisms of iron acquisition in C. neoformans, we established a role for Ypt7 in growth on heme as the sole iron source. Deletion of YPT7 also caused abnormal vacuolar morphology, defective endocytic trafficking and autophagy, and mislocalization of Aph1, a secreted vacuolar acid phosphatase. Ypt7 localized to the vacuolar membrane and membrane contact sites between the vacuole and mitochondria (vCLAMPs), and loss of the protein impaired growth on inhibitors of the electron transport chain. Additionally, Ypt7 was required for robust growth at 39°C, a phenotype likely involving the calcineurin signaling pathway because ypt7 mutants displayed increased susceptibility to the calcineurin-specific inhibitors, FK506 and cyclosporin A; the mutants also had impaired growth in either limiting or high levels of calcium. Finally, Ypt7 was required for survival during interactions with macrophages, and ypt7 mutants were attenuated for virulence in a mouse inhalation model thus demonstrating the importance of membrane trafficking functions in cryptococcosis.
RESUMEN
Mitochondrial functions are critical for the ability of the fungal pathogen Cryptococcus neoformans to cause disease. However, mechanistic connections between key functions such as the mitochondrial electron transport chain (ETC) and virulence factor elaboration have yet to be thoroughly characterized. Here, we observed that inhibition of ETC complex III suppressed melanin formation, a major virulence factor. This inhibition was partially overcome by defects in Cir1 or HapX, two transcription factors that regulate iron acquisition and use. In this regard, loss of Cir1 derepresses the expression of laccase genes as a potential mechanism to restore melanin, while HapX may condition melanin formation by controlling oxidative stress. We hypothesize that ETC dysfunction alters redox homeostasis to influence melanin formation. Consistent with this idea, inhibition of growth by hydrogen peroxide was exacerbated in the presence of the melanin substrate L-DOPA. In addition, loss of the mitochondrial chaperone Mrj1, which influences the activity of ETC complex III and reduces ROS accumulation, also partially overcame antimycin A inhibition of melanin. The phenotypic impact of mitochondrial dysfunction was consistent with RNA-Seq analyses of WT cells treated with antimycin A or L-DOPA, or cells lacking Cir1 that revealed influences on transcripts encoding mitochondrial functions (e.g., ETC components and proteins for Fe-S cluster assembly). Overall, these findings reveal mitochondria-nuclear communication via ROS and iron regulators to control virulence factor production in C. neoformans.IMPORTANCEThere is a growing appreciation of the importance of mitochondrial functions and iron homeostasis in the ability of fungal pathogens to sense the vertebrate host environment and cause disease. Many mitochondrial functions such as heme and iron-sulfur cluster biosynthesis, and the electron transport chain (ETC), are dependent on iron. Connections between factors that regulate iron homeostasis and mitochondrial activities are known in model yeasts and are emerging for fungal pathogens. In this study, we identified connections between iron regulatory transcription factors (e.g., Cir1 and HapX) and the activity of complex III of the ETC that influence the formation of melanin, a key virulence factor in the pathogenic fungus Cryptococcus neoformans. This fungus causes meningoencephalitis in immunocompromised people and is a major threat to the HIV/AIDS population. Thus, understanding how mitochondrial functions influence virulence may support new therapeutic approaches to combat diseases caused by C. neoformans and other fungi.
Asunto(s)
Cryptococcus neoformans , Melaninas , Melaninas/metabolismo , Cryptococcus neoformans/genética , Cryptococcus neoformans/patogenicidad , Cryptococcus neoformans/metabolismo , Hierro/metabolismo , Transporte de Electrón , Mitocondrias/metabolismo , Proteínas Reguladoras del Hierro/metabolismo , Proteínas Reguladoras del Hierro/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Factores de Virulencia/metabolismo , Factores de Virulencia/genética , Estrés Oxidativo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Proteínas del Complejo de Cadena de Transporte de Electrón/genéticaRESUMEN
We studied the mechanisms of eye movement desensitization and reprocessing (EMDR) and imagery rescripting (ImRs). We hypothesized that EMDR works via changes in memory vividness, that ImRs works via changes in encapsulated beliefs (EB), and that both treatments work via changes in memory distress. Patients (N = 155) with childhood-related posttraumatic stress disorder (Ch-PTSD) received 12 sessions of EMDR or ImRs. The vividness, distress, and EB related to the index trauma were measured with the Imagery Interview. PTSD severity was assessed with the Impact of Events Scale-Revised and the Clinician-Administered PTSD Scale for DSM-5. We conducted mixed regressions and Granger causality analyses. EMDR led to initially stronger changes in all predictors, but only for distress this was retained until the last assessment. No evidence for vividness as a predictive variable was found. However, changes in distress and EB predicted changes in PTSD severity during ImRs. These findings partially support the hypothesized mechanisms of ImRs, while no support was found for the hypothesized mechanisms of EMDR. Differences in the timing of addressing the index trauma during treatment and the timing of assessments could have influenced the findings. This study provides insight into the relative effectiveness and working mechanisms of these treatments.
Asunto(s)
Terapia Cognitivo-Conductual , Desensibilización y Reprocesamiento del Movimiento Ocular , Trastornos por Estrés Postraumático , Humanos , Niño , Movimientos Oculares , Resultado del Tratamiento , Trastornos por Estrés Postraumático/terapiaRESUMEN
BACKGROUND: Pleural mesothelioma usually presents at an advanced, incurable stage. Chemotherapy with platinum-pemetrexed is a standard treatment. We hypothesised that the addition of pembrolizumab to platinum-pemetrexed would improve overall survival in patients with pleural mesothelioma. METHODS: We did this open-label, international, randomised phase 3 trial at 51 hospitals in Canada, Italy, and France. Eligible participants were aged 18 years or older, with previously untreated advanced pleural mesothelioma, with an Eastern Cooperative Oncology Group performance status score of 0 or 1. Patients were randomly assigned (1:1) to intravenous chemotherapy (cisplatin [75 mg/m2] or carboplatin [area under the concentration-time curve 5-6 mg/mL per min] with pemetrexed 500 mg/m2, every 3 weeks for up to 6 cycles), with or without intravenous pembrolizumab 200 mg every 3 weeks (up to 2 years). The primary endpoint was overall survival in all randomly assigned patients; safety was assessed in all randomly assigned patients who received at least one dose of study therapy. This trial is registered with ClinicalTrials.gov, NCT02784171, and is closed to accrual. FINDINGS: Between Jan 31, 2017, and Sept 4, 2020, 440 patients were enrolled and randomly assigned to chemotherapy alone (n=218) or chemotherapy with pembrolizumab (n=222). 333 (76 %) of patients were male, 347 (79%) were White, and median age was 71 years (IQR 66-75). At final analysis (database lock Dec 15, 2022), with a median follow-up of 16·2 months (IQR 8·3-27·8), overall survival was significantly longer with pembrolizumab (median overall survival 17·3 months [95% CI 14·4-21·3] with pembrolizumab vs 16·1 months [13·1-18·2] with chemotherapy alone, hazard ratio for death 0·79; 95% CI 0·64-0·98, two-sided p=0·0324). 3-year overall survival rate was 25% (95% CI 20-33%) with pembrolizumab and 17% (13-24%) with chemotherapy alone. Adverse events related to study treatment of grade 3 or 4 occurred in 60 (27%) of 222 patients in the pembrolizumab group and 32 (15%) of 211 patients in the chemotherapy alone group. Hospital admissions for serious adverse events related to one or more study drugs were reported in 40 (18%) of 222 patients in the pembrolizumab group and 12 (6%) of 211 patients in the chemotherapy alone group. Grade 5 adverse events related to one or more drugs occurred in two patients on the pembrolizumab group and one patient in the chemotherapy alone group. INTERPRETATION: In patients with advanced pleural mesothelioma, the addition of pembrolizumab to standard platinum-pemetrexed chemotherapy was tolerable and resulted in a significant improvement in overall survival. This regimen is a new treatment option for previously untreated advanced pleural mesothelioma. FUNDING: The Canadian Cancer Society and Merck & Co.
Asunto(s)
Mesotelioma Maligno , Mesotelioma , Humanos , Masculino , Anciano , Femenino , Pemetrexed/efectos adversos , Platino (Metal)/uso terapéutico , Canadá/epidemiología , Mesotelioma Maligno/tratamiento farmacológico , Mesotelioma/tratamiento farmacológico , Mesotelioma/inducido químicamente , Protocolos de Quimioterapia Combinada AntineoplásicaRESUMEN
The corn smut fungus, Ustilago maydis, is an excellent model for studying biotrophic plant-pathogen interactions, including nutritional adaptation to the host environment. Iron acquisition during host colonization is a key aspect of microbial pathogenesis yet less is known about this process for fungal pathogens of plants. Monothiol glutaredoxins are central regulators of key cellular functions in fungi, including iron homeostasis, cell wall integrity, and redox status via interactions with transcription factors, iron-sulfur clusters, and glutathione. In this study, the roles of the monothiol glutaredoxin Grx4 in the biology of U. maydis were investigated by constructing strains expressing a conditional allele of grx4 under the control of the arabinose-inducible, glucose-repressible promoter Pcrg1. The use of conditional expression was necessary because Grx4 appeared to be essential for U. maydis. Transcriptome and genetic analyses with strains depleted in Grx4 revealed that the protein participates in the regulation of iron acquisition functions and is necessary for the ability of U. maydis to cause disease on maize seedlings. Taken together, this study supports the growing appreciation of monothiol glutaredoxins as key regulators of virulence-related phenotypes in pathogenic fungi.
RESUMEN
Sudden gains, defined as large and stable improvements in symptom severity during psychological treatment, have consistently been found to be associated with better outcomes across treatments and diagnoses. Yet, insights on coherent predictors of sudden gains and on emotional changes around sudden gains in post-traumatic stress disorder (PTSD) are lacking. We aimed at replicating a measure of intraindividual variability as a predictor for sudden gains and testing its independence from change during treatment. Furthermore, we expected changes in emotions of guilt, shame and disgust prior to sudden gains to predict sudden gains. Data from a pre-registered randomized controlled trial (RCT) of eye-movement desensitization and reprocessing (emdr) and Imagery Rescripting (ImRs) for PTSD in 155 adult survivors of childhood abuse were used. Intraindividual variability of PTSD symptoms in both treatments did not predict sudden gains status and was not independent of change during treatment. In the EMDR condition, levels of shame during treatment predicted sudden gains and shame decreased shortly before a sudden gain in both treatments. Reductions in all emotions during sudden gains were significantly higher for participants with sudden gains than for comparable intervals in non-sudden gainers. Our findings do not support the predictive validity of intraindividual variability for sudden gains. The decrease of guilt, shame and disgust during sudden gains warrants further research on their role as a mechanism of treatment change for PTSD.
Asunto(s)
Maltrato a los Niños , Desensibilización y Reprocesamiento del Movimiento Ocular , Trastornos por Estrés Postraumático , Adulto , Humanos , Niño , Trastornos por Estrés Postraumático/terapia , Trastornos por Estrés Postraumático/psicología , Culpa , Vergüenza , Resultado del TratamientoRESUMEN
Immune checkpoint inhibitors have activity in mesothelioma. IND.227 was a phase 2 trial (120 patients planned) comparing progression-free survival of standard platinum and pemetrexed (CP) versus CP + pembrolizumab (pembro) versus pembro. Accrual to the pembro arm was discontinued on the basis of interim analysis (IA-16 wk disease control rate). CP + pembro was tolerable, with progression-free survival similar between arms and median survival and overall response rate higher than those of CP alone (19.8 mo [95% confidence interval or CI: 8.4-41.36] versus 8.9 mo [95% CI: 5.3-12.8] and 47% [95% CI: 24%-71%] versus 19% [95% CI: 5%-42%], respectively). The subsequent phase 3 trial has completed accrual; results are expected in 2023.
Asunto(s)
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurales , Humanos , Neoplasias Pulmonares/patología , Canadá , Mesotelioma/patología , Pemetrexed/farmacología , Pemetrexed/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pleurales/patologíaRESUMEN
Despite unequivocal roles in disease, transcription factors (TFs) remain largely untapped as pharmacologic targets due to the challenges in targeting protein-protein and protein-DNA interactions. Here we report a chemical strategy to generate modular synthetic transcriptional repressors (STRs) derived from the bHLH domain of MAX. Our synthetic approach yields chemically stabilized tertiary domain mimetics that cooperatively bind the MYC/MAX consensus E-box motif with nanomolar affinity, exhibit specificity that is equivalent to or beyond that of full-length TFs and directly compete with MYC/MAX protein for DNA binding. A lead STR directly inhibits MYC binding in cells, downregulates MYC-dependent expression programs at the proteome level and inhibits MYC-dependent cell proliferation. Co-crystallization and structure determination of a STR:E-box DNA complex confirms retention of DNA recognition in a near identical manner as full-length bHLH TFs. We additionally demonstrate structure-blind design of STRs derived from alternative bHLH-TFs, confirming that STRs can be used to develop highly specific mimetics of TFs targeting other gene regulatory elements.
Asunto(s)
Proteínas Proto-Oncogénicas c-myc , Factores de Transcripción , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/química , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factores de Transcripción/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Secuencias Hélice-Asa-Hélice , Secuencias Reguladoras de Ácidos Nucleicos , ADN/genética , ADN/metabolismoRESUMEN
Many plant-associated fungi are obligate biotrophs that depend on living hosts to proliferate. However, little is known about the molecular basis of the biotrophic lifestyle, despite the impact of fungi on the environment and food security. In this work, we show that combinations of organic acids and glucose trigger phenotypes that are associated with the late stage of biotrophy for the maize pathogen Ustilago maydis. These phenotypes include the expression of a set of effectors normally observed only during biotrophic development, as well as the formation of melanin associated with sporulation in plant tumors. U. maydis and other hemibiotrophic fungi also respond to a combination of carbon sources with enhanced proliferation. Thus, the response to combinations of nutrients from the host may be a conserved feature of fungal biotrophy.
Asunto(s)
Ácidos Dicarboxílicos , Glucosa , Interacciones Huésped-Patógeno , Tumores de Planta , Ustilago , Zea mays , Ácidos Dicarboxílicos/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glucosa/metabolismo , Tumores de Planta/microbiología , Ustilago/genética , Ustilago/metabolismo , Ustilago/patogenicidad , Virulencia , Zea mays/microbiologíaRESUMEN
IMPORTANCE: Schema therapy (ST), delivered either in an individual or group format, has been compared with other active treatments for borderline personality disorder (BPD). To our knowledge, the 2 formats have not been compared with treatment as usual (TAU) or with each other. Such comparisons help determine best treatment practices. OBJECTIVE: To evaluate whether ST is more effectively delivered in a predominantly group or combined individual and group format and whether ST is more effective than optimal TAU for BPD. DESIGN, SETTING, AND PARTICIPANTS: In this multicenter, 3-arm randomized clinical trial conducted at 15 sites in 5 countries (Australia, Germany, Greece, the Netherlands, and the UK), outpatients aged 18 to 65 years who had BPD were recruited between June 29, 2010, and May 18, 2016, to receive either predominantly group ST (PGST), combined individual and group ST (IGST), or optimal TAU. Data were analyzed from June 4, 2019, to December 29, 2021. INTERVENTIONS: At each site, cohorts of 16 to 18 participants were randomized 1:1 to PGST vs TAU or IGST vs TAU. Both ST formats were delivered over 2 years, with 2 sessions per week in year 1 and the frequency gradually decreasing during year 2. Assessments were collected by blinded assessors. MAIN OUTCOMES AND MEASURES: The primary outcome was the change in BPD severity over time, assessed with the Borderline Personality Disorder Severity Index (BPDSI) total score. Treatment retention was analyzed as a secondary outcome using generalized linear mixed model survival analysis. RESULTS: Of 495 participants (mean [SD] age, 33.6 [9.4] years; 426 [86.2%] female), 246 (49.7%) received TAU, 125 (25.2%) received PGST, and 124 (25.0%) received IGST (1 of whom later withdrew consent). PGST and IGST combined were superior to TAU with regard to reduced BPD severity (Cohen d, 0.73; 95% CI, 0.29-1.18; P < .001). For this outcome, IGST was superior to TAU (Cohen d, 1.14; 95% CI, 0.57-1.71; P < .001) and PGST (Cohen d, 0.84; 95% CI, 0.09-1.59; P = .03), whereas PGST did not differ significantly from TAU (Cohen d, 0.30; 95% CI, -0.29 to 0.89; P = .32). Treatment retention was greater in the IGST arm than in the PGST (1 year: 0.82 vs 0.72; 2 years: 0.74 vs. 0.62) and TAU (1 year: 0.82 vs 0.73; 2 years: 0.74 vs 0.64) arms, and there was no significant difference between the TAU and PGST arms (1 year: 0.73 vs 0.72; 2 years: 0.64 vs 0.62). CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, IGST was more effective and had greater treatment retention compared with TAU and PGST. These findings suggest that IGST is the preferred ST format, with high retention and continuation of improvement in BPD severity after the completion of treatment. TRIAL REGISTRATION: trialregister.nl Identifier: NTR2392.
Asunto(s)
Trastorno de Personalidad Limítrofe , Psicoterapia de Grupo , Adolescente , Adulto , Anciano , Trastorno de Personalidad Limítrofe/terapia , Femenino , Alemania , Humanos , Persona de Mediana Edad , Pacientes Ambulatorios , Terapia de Esquemas , Resultado del Tratamiento , Adulto JovenRESUMEN
Although life-history trade-offs are central to life-history evolution, their mechanistic basis is often unclear. Traditionally, trade-offs are understood in terms of competition for limited resources among traits within an organism, which could be mediated by signal transduction pathways at the level of cellular metabolism. Nevertheless, trade-offs are also thought to be produced as a consequence of the performance of one activity generating negative consequences for other traits, or the result of genes or pathways that simultaneously regulate two life-history traits in opposite directions (antagonistic pleiotropy), independent of resource allocation. Yet examples of genes with antagonistic effects on life-history traits are limited. This study provides direct evidence for a gene-RLS1, that is involved in increasing survival in nutrient-limiting environments at a cost to immediate reproduction in the single-celled photosynthetic alga, Chlamydomonas reinhardtii. Specifically, we show that RLS1 mutants are unable to properly suppress their reproduction in phosphate-deprived conditions. Although these mutants have an immediate reproductive advantage relative to the parental strain, their long-term survival is negatively affected. Our data suggest that RLS1 is a bona fide life-history trade-off gene that suppresses immediate reproduction and ensures survival by downregulating photosynthesis in limiting environments, as part of the general acclimation response to nutrient deprivation in photosynthetic organisms.
Asunto(s)
Reproducción , Fenotipo , Reproducción/fisiologíaRESUMEN
Histone chaperoning ensures genomic integrity during routine processes such as DNA replication and transcription as well as DNA repair upon damage. Here, we identify a nuclear J domain protein, Dnj4, in the fungal pathogen Cryptococcus neoformans and demonstrate that it interacts with histones 3 and 4, suggesting a role as a histone chaperone. In support of this idea, a dnj4Δ deletion mutant had elevated levels of DNA damage and was hypersensitive to DNA-damaging agents. The transcriptional response to DNA damage was also impaired in the dnj4Δ mutant. Genes related to DNA damage and iron homeostasis were upregulated in the wild-type strain in response to hydroxyurea treatment; however, their upregulation was either absent from or reduced in the dnj4Δ mutant. Accordingly, excess iron rescued the mutant's growth in response to DNA-damaging agents. Iron homeostasis is crucial for virulence in C. neoformans; however, Dnj4 was found to be dispensable for disease in a mouse model of cryptococcosis. Finally, we confirmed a conserved role for Dnj4 as a histone chaperone by expressing it in Saccharomyces cerevisiae and showing that it disrupted endogenous histone chaperoning. Altogether, this study highlights the importance of a JDP cochaperone in maintaining genome integrity in C. neoformans. IMPORTANCE DNA replication, gene expression, and genomic repair all require precise coordination of the many proteins that interact with DNA. This includes the histones as well as their chaperones. In this study, we show that a histone chaperone, Dnj4, is required for genome integrity and for the response to DNA damage. The gene encoding this protein in Cryptococcus neoformans lacks an ortholog in Saccharomyces cerevisiae; however, it is conserved in humans in which its ortholog is essential. Since it is not essential in C. neoformans, we were able to generate deletion mutants to characterize the roles of Dnj4. We also expressed Dnj4 in S. cerevisiae, in which it was able to bind S. cerevisiae histones and interfere with existing histone chaperoning machinery. Therefore, we show a conserved role for Dnj4 in histone chaperoning that suggests that C. neoformans is useful to better understand aspects of this important biological process.
Asunto(s)
Criptococosis/microbiología , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Daño del ADN , Proteínas Fúngicas/metabolismo , Chaperonas de Histonas/metabolismo , Cryptococcus neoformans/química , Cryptococcus neoformans/crecimiento & desarrollo , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Chaperonas de Histonas/química , Chaperonas de Histonas/genética , Histonas/genética , Histonas/metabolismo , Humanos , Hierro/metabolismo , Unión Proteica , Dominios ProteicosRESUMEN
BACKGROUND: Trauma-focused treatments for posttraumatic stress disorder (PTSD) are commonly delivered either once or twice a week. Initial evidence suggests that session frequency affects treatment response, but very few trials have investigated the effect of session frequency. The present study's aim is to compare treatment outcomes of twice-weekly versus once-weekly sessions of two treatments for PTSD related to childhood trauma, imagery rescripting (ImRs) and eye movement desensitization and reprocessing (EMDR). We hypothesize that both treatments will be more effective when delivered twice than once a week. How session frequency impacts treatment response, whether treatment type moderates the frequency effect, and which treatment type and frequency works best for whom will also be investigated. METHODS: The IREM-Freq trial is an international multicenter randomized clinical trial conducted in mental healthcare centers across Australia, Germany, and the Netherlands. We aim to recruit 220 participants, who will be randomized to one of four conditions: (1) EMDR once a week, (2) EMDR twice a week, (3) ImRs once a week, or (4) ImRs twice a week. Treatment consists of 12 sessions. Data are collected at baseline until one-year follow-up. The primary outcome measure is clinician-rated PTSD symptom severity. Secondary outcome measures include self-reported PTSD symptom severity, complex PTSD symptoms, trauma-related cognitions and emotions, depressive symptoms, dissociation, quality of life, and functioning. Process measures include memory, learning, therapeutic alliance, motivation, reluctance, and avoidance. Additional investigations will focus on predictors of treatment outcome and PTSD severity, change mechanisms of EMDR and ImRs, the role of emotions, cognitions, and memory, the optimization of treatment selection, learned helplessness, perspectives of patients and therapists, the network structure of PTSD symptoms, and sudden treatment gains. DISCUSSION: This study will extend our knowledge on trauma-focused treatments for PTSD related to childhood trauma and, more specifically, the importance of session frequency. More insight into the optimal session frequency could lead to improved treatment outcomes and less dropout, and in turn, to a reduction of healthcare costs. Moreover, the additional investigations will broaden our understanding of how the treatments work and variables that affect treatment outcome. TRIAL REGISTRATION: Netherlands Trial Register NL6965, registered 25/04/2018.
Asunto(s)
Desensibilización y Reprocesamiento del Movimiento Ocular , Trastornos por Estrés Postraumático , Adulto , Movimientos Oculares , Humanos , Imágenes en Psicoterapia , Estudios Multicéntricos como Asunto , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/terapia , Resultado del TratamientoRESUMEN
The capacity of opportunistic fungal pathogens such as Cryptococcus neoformans to cause disease is dependent on their ability to overcome an onslaught of stresses including elevated temperature under mammalian host conditions. Protein chaperones and co-chaperones play key roles in thermotolerance. In this study, we characterized the role of the endoplasmic reticulum (ER) J-domain containing co-chaperone, Dnj1, in the virulence of C. neoformans. A strain expressing a Dnj1-GFP fusion protein was used to confirm localization to the ER, and a dnj1∆ deletion mutant was shown to be hypersensitive to the ER stress caused by tunicamycin (TM) or 4µ8C. Dnj1 and another ER chaperone, calnexin were found to coordinately maintain ER homeostasis and contribute to maintenance of cell wall architecture. Dnj1 also contributed to thermotolerance and increased in abundance at elevated temperatures representative of febrile patients (e.g., 39°C) thus highlighting its role as a temperature-responsive J domain protein. The elaboration of virulence factors such as the polysaccharide capsule and extracellular urease activity were also markedly impaired in the dnj1∆ mutant when induced at human body temperature (i.e., 37°C). These virulence factors are immunomodulatory and, indeed, infection with the dnj1∆ mutant revealed impaired induction of the cytokines IL-6, IL-10, and MCP-1 in the lungs of mice compared to infection with wild type or complemented strains. The dnj1∆ mutant also had attenuated virulence in an intranasal murine model of cryptococcosis. Altogether, our data indicate that Dnj1 is crucial for survival and virulence factor production at elevated temperatures. The characterization of this co-chaperone also highlights the importance of maintaining homeostasis in the ER for the pathogenesis of C. neoformans.
RESUMEN
Patients with posttraumatic stress disorder (PTSD) frequently have comorbid diagnoses such as major depressive disorder (MDD) and anxiety disorders (AD). Studies into the impact of these comorbidities on the outcome of PTSD treatment have yielded mixed results. The different treatments investigated in these studies might explain the varied outcome. The purpose of this study was to examine the impact of these comorbidities on the outcome of two specific PTSD treatments. MDD and AD were analyzed as predictors and moderators in a trial comparing 12 sessions of either eye movement desensitization and reprocessing (EMDR) or imagery rescripting (IR) in 155 adult patients with PTSD from childhood trauma. The primary outcome was reduction of PTSD symptoms (clinician-administered PTSD Scale for DSM-5, CAPS-5) assessed at eight-week follow-up and a secondary outcome was self-report PTSD symptoms (Impact of Event Scale, IES-R). MDD was not a predictor of treatment outcome but did have a significant moderator effect. Patients with MDD showed a better outcome if they were treated with IR, whereas patients without MDD improved more in the EMDR condition. No impact of AD emerged. It seems essential to consider comorbid MDD when planning PTSD treatment to improve treatment outcomes. More research is needed to replicate our findings and focus on different kinds of PTSD treatments and other comorbidities.
RESUMEN
BACKGROUND: Childhood maltreatment is relatively common and is related to a range of negative consequences, such as Posttraumatic Stress Disorder (PTSD). There are indications that various maltreatment types are related to PTSD severity, although not all types, such as emotional abuse, meet the PTSD Criterion-A. OBJECTIVE: The aim of the present study was to examine the relationship between 5 types of childhood maltreatment (i.e., sexual, physical, and emotional abuse, and physical and emotional neglect) and the severity of adult PTSD and PTSD symptoms. PARTICIPANTS AND SETTING: Adult participants (N = 147) with Childhood-related PTSD (Ch-PTSD) recruited from clinical sites completed the Childhood Trauma Questionnaire-short form (CTQ-sf) and 2 PTSD measures: The Clinician Administered PTSD Scale for DSM-5 (CAPS-5) and the PTSD Checklist for DSM-5 (PCL-5). METHODS: Childhood maltreatment predictors and 2 covariates, age and gender, were analysed in multivariate multilevel models as participants were nested within sites. A model selection procedure, in which all combinations of predictors were examined, was used to select a final set of predictors. RESULTS: The results indicated that emotional abuse was the only trauma type that was significantly related to severity of PTSD and to the severity of specific PTSD symptom clusters (r between 0.130 and 0.338). The final models explained between 6.5% and 16.7% of the variance in PTSD severity. CONCLUSIONS: The findings suggest that emotional abuse plays a more important role in Ch-PTSD than hitherto assumed, and that treatment should not neglect processing of childhood emotional abuse.
Asunto(s)
Maltrato a los Niños , Trastornos por Estrés Postraumático , Adulto , Niño , Maltrato a los Niños/psicología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Humanos , Trastornos por Estrés Postraumático/psicología , Encuestas y CuestionariosRESUMEN
This study aimed to explore patients' and therapists' experiences with trauma-focused treatments in patients with posttraumatic stress disorder from childhood trauma (Ch-PTSD). Semi-structured interviews were conducted with patients (n = 44) and therapists (n = 16) from an international multicentre randomised clinical trial comparing two trauma-focused treatments (IREM), imagery rescripting and eye movement and desensitisation (EMDR). Thematic analysis was used to identify key themes within the data. Patients and therapists commented about the process of therapy. The themes that emerged from these comments included the importance of the patients' willingness to engage and commit to the treatment process; the importance and difficulty of the trauma work, observations of how the trauma focused therapy produced changes in insight, and sense of self and empowerment for the future. In addition, therapists made suggestions for optimising the therapist role in the trauma-focused treatment. This included the importance of having confidence in their own ability, confronting their own and their client's avoidance and the necessity and difficulties of adhering to the treatment protocols. These reported experiences add further support to the idea that trauma-focused treatments, without a stabilisation phase, can be tolerated and deepens our understanding of how to make this palatable for individuals with Ch-PTSD.
RESUMEN
BACKGROUND: Investigation of treatments that effectively treat adults with post-traumatic stress disorder from childhood experiences (Ch-PTSD) and are well tolerated by patients is needed to improve outcomes for this population. AIMS: The purpose of this study was to compare the effectiveness of two trauma-focused treatments, imagery rescripting (ImRs) and eye movement desensitisation and reprocessing (EMDR), for treating Ch-PTSD. METHOD: We conducted an international, multicentre, randomised clinical trial, recruiting adults with Ch-PTSD from childhood trauma before 16 years of age. Participants were randomised to treatment condition and assessed by blind raters at multiple time points. Participants received up to 12 90-min sessions of either ImRs or EMDR, biweekly. RESULTS: A total of 155 participants were included in the final intent-to-treat analysis. Drop-out rates were low, at 7.7%. A generalised linear mixed model of repeated measures showed that observer-rated post-traumatic stress disorder (PTSD) symptoms significantly decreased for both ImRs (d = 1.72) and EMDR (d = 1.73) at the 8-week post-treatment assessment. Similar results were seen with secondary outcome measures and self-reported PTSD symptoms. There were no significant differences between the two treatments on any standardised measure at post-treatment and follow-up. CONCLUSIONS: ImRs and EMDR treatments were found to be effective in treating PTSD symptoms arising from childhood trauma, and in reducing other symptoms such as depression, dissociation and trauma-related cognitions. The low drop-out rates suggest that the treatments were well tolerated by participants. The results from this study provide evidence for the use of trauma-focused treatments for Ch-PTSD.