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1.
bioRxiv ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38854088

RESUMEN

Background: Anorexia nervosa (AN) is a mental and behavioral health condition characterized by an intense fear of weight or fat gain, severe restriction of food intake resulting in low body weight, and distorted self-perception of body shape or weight. While substantial research has focused on general anxiety in AN, less is known about eating-related anxiety and its underlying neural mechanisms. Therefore, we sought to characterize anxiety-to-eat in AN and examine the neurometabolic profile within the dorsal anterior cingulate cortex (dACC), a brain region putatively involved in magnifying the threat response. Methods: Women seeking inpatient treatment for AN and women of healthy weight without a lifetime history of an eating disorder (healthy controls; HC) completed a computer-based behavioral task assessing anxiety-to-eat in response to images of higher (HED) and lower (LED) energy density foods. Participants also underwent magnetic resonance spectroscopy of the dACC in a 3 Tesla scanner. Results: The AN group reported greater anxiety to eat HED and LED foods relative to the HC group. Both groups reported greater anxiety to eat HED foods relative to LED foods. The neurometabolite myo-inositol (mI) was lower in the dACC in AN relative to HC, and mI levels negatively predicted anxiety to eat HED but not LED foods in the AN group only. mI levels in the dACC were independent of body weight, body mass, and general anxiety. Conclusions: These findings provide critical new insight into the clinically challenging feature and underlying neural mechanisms of eating-related anxiety and indicate mI levels in the dACC could serve as a novel biomarker of illness severity that is independent of body weight to identify individuals vulnerable to disordered eating or eating pathology as well as a potential therapeutic target.

2.
J Neurosci ; 44(22)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38604780

RESUMEN

The autonomic nervous system (ANS) regulates the body's physiology, including cardiovascular function. As the ANS develops during the second to third trimester, fetal heart rate variability (HRV) increases while fetal heart rate (HR) decreases. In this way, fetal HR and HRV provide an index of fetal ANS development and future neurobehavioral regulation. Fetal HR and HRV have been associated with child language ability and psychomotor development behavior in toddlerhood. However, their associations with postbirth autonomic brain systems, such as the brainstem, hypothalamus, and dorsal anterior cingulate cortex (dACC), have yet to be investigated even though brain pathways involved in autonomic regulation are well established in older individuals. We assessed whether fetal HR and HRV were associated with the brainstem, hypothalamic, and dACC functional connectivity in newborns. Data were obtained from 60 pregnant individuals (ages 14-42) at 24-27 and 34-37 weeks of gestation using a fetal actocardiograph to generate fetal HR and HRV. During natural sleep, their infants (38 males and 22 females) underwent a fMRI scan between 40 and 46 weeks of postmenstrual age. Our findings relate fetal heart indices to brainstem, hypothalamic, and dACC connectivity and reveal connections with widespread brain regions that may support behavioral and emotional regulation. We demonstrated the basic physiologic association between fetal HR indices and lower- and higher-order brain regions involved in regulatory processes. This work provides the foundation for future behavioral or physiological regulation research in fetuses and infants.


Asunto(s)
Tronco Encefálico , Giro del Cíngulo , Frecuencia Cardíaca Fetal , Hipotálamo , Imagen por Resonancia Magnética , Humanos , Femenino , Masculino , Giro del Cíngulo/fisiología , Giro del Cíngulo/diagnóstico por imagen , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/fisiología , Recién Nacido , Embarazo , Frecuencia Cardíaca Fetal/fisiología , Adulto , Hipotálamo/fisiología , Hipotálamo/diagnóstico por imagen , Hipotálamo/embriología , Adolescente , Adulto Joven , Mapeo Encefálico/métodos , Vías Nerviosas/fisiología
3.
Biol Psychiatry ; 96(2): 137-146, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38336216

RESUMEN

BACKGROUND: Individuals with obsessive-compulsive disorder (OCD) show persistent avoidance behaviors, often in the absence of actual threat. Quality-of-life costs and heterogeneity support the need for novel brain-behavior intervention targets. Informed by mechanistic and anatomical studies of persistent avoidance in rodents and nonhuman primates, our goal was to test whether connections within a hypothesized persistent avoidance-related network predicted OCD-related harm avoidance (HA), a trait measure of persistent avoidance. We hypothesized that 1) HA, not an OCD diagnosis, would be associated with altered endogenous connectivity in at least one connection in the network; 2) HA-specific findings would be robust to comorbid symptoms; and 3) reliable findings would replicate in a holdout testing subsample. METHODS: Using resting-state functional connectivity magnetic resonance imaging, cross-validated elastic net for feature selection, and Poisson generalized linear models, we tested which connections significantly predicted HA in our training subsample (n = 73; 71.8% female; healthy control group n = 36, OCD group n = 37); robustness to comorbidities; and replicability in a testing subsample (n = 30; 56.7% female; healthy control group n = 15, OCD group n = 15). RESULTS: Stronger inverse connectivity between the right dorsal anterior cingulate cortex and right basolateral amygdala and stronger positive connectivity between the right ventral anterior insula and left ventral striatum were associated with greater HA across groups. Network connections did not discriminate OCD diagnostic status or predict HA-correlated traits, suggesting sensitivity to trait HA. The dorsal anterior cingulate cortex-basolateral amygdala relationship was robust to controlling for comorbidities and medication in individuals with OCD and was also predictive of HA in our testing subsample. CONCLUSIONS: Stronger inverse dorsal anterior cingulate cortex-basolateral amygdala connectivity was robustly and reliably associated with HA across groups and in OCD. Results support the relevance of a cross-species persistent avoidance-related network to OCD, with implications for precision-based approaches and treatment.


Asunto(s)
Imagen por Resonancia Magnética , Trastorno Obsesivo Compulsivo , Trastorno Obsesivo Compulsivo/fisiopatología , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Humanos , Masculino , Femenino , Adulto , Vías Nerviosas/fisiopatología , Vías Nerviosas/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Adulto Joven , Reacción de Prevención/fisiología , Reducción del Daño
4.
Psychol Med ; 54(1): 159-168, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37129070

RESUMEN

BACKGROUND: Difficulties in the context-dependent modulation of conditioned fear are known for posttraumatic stress disorder and may explain the occurrence of intrusive memories in safe contexts. The current study therefore investigated if reduced context-dependent modulation of conditioned fear and its underlying neural circuitry constitute risk factors for the development of analog intrusions in response to an experimental trauma. METHODS: Eighty-five healthy women participated in the trauma film paradigm to investigate the development of analog intrusions as well as explicit memory for an experimental trauma after one week and three months, respectively. Before, participants underwent a context-dependent fear conditioning paradigm during functional magnetic resonance imaging with fear acquisition in context A and extinction training in context B on a first day, as well as extinction recall in context B and fear renewal in a novel context C one day later. Skin conductance responses (SCRs) and blood oxygen level dependent responses were main outcome measures. RESULTS: In addition to stronger fear acquisition in context A, stronger conditioned fear responses in the safe context B, as indicated by stronger conditioned SCRs or stronger activation of fear expressing regions during extinction learning and recall, predicted the development of long-term analog intrusions. CONCLUSIONS: Stronger fear responses in safe and danger contexts were risk factors for the development of long-term analog intrusions and point to decontextualized fear memories and difficulties in the context-dependent modulation of conditioned fear. Altered fear conditioning processes and reduced storage of contextual information may cause the occurrence of fear independent of context.


Asunto(s)
Extinción Psicológica , Respuesta Galvánica de la Piel , Humanos , Femenino , Extinción Psicológica/fisiología , Miedo/fisiología , Condicionamiento Clásico/fisiología , Recuerdo Mental/fisiología , Imagen por Resonancia Magnética
5.
Brain Sci ; 13(10)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37891756

RESUMEN

Recognizing highly occluded objects is believed to arise from the interaction between the brain's vision and cognition-controlling areas, although supporting neuroimaging data are currently limited. To explore the neural mechanism during this activity, we conducted an occlusion object recognition experiment using functional magnetic resonance imaging (fMRI). During magnet resonance examinations, 66 subjects engaged in object recognition tasks with three different occlusion degrees. Generalized linear model (GLM) analysis showed that the activation degree of the occipital lobe (inferior occipital gyrus, middle occipital gyrus, and occipital fusiform gyrus) and dorsal anterior cingulate cortex (dACC) was related to the occlusion degree of the objects. Multivariate pattern analysis (MVPA) further unearthed a considerable surge in classification precision when dACC activation was incorporated as a feature. This suggested the combined role of dACC and the occipital lobe in occluded object recognition tasks. Moreover, psychophysiological interaction (PPI) analysis disclosed that functional connectivity (FC) between the dACC and the occipital lobe was enhanced with increased occlusion, highlighting the necessity of FC between these two brain regions in effectively identifying exceedingly occluded objects. In conclusion, these findings contribute to understanding the neural mechanisms of highly occluded object recognition, augmenting our appreciation of how the brain manages incomplete visual data.

6.
J Wound Care ; 32(Sup8a): S13-S22, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37591666

RESUMEN

OBJECTIVE: To update the evidence in relation to the use of dialkylcarbamoyl chloride (DACC)-coated wound dressings in the prevention, treatment and management of wounds. METHOD: PubMed and PubMed Central databases were searched to identify articles published since 2020 describing the experimental and clinical evidence for DACC-coated dressings, and their antimicrobial effect, as well as their impact on the prevention and treatment of infected wounds. The identified articles were then narratively reviewed. RESULTS: The search yielded 113 articles (plus references from ad hoc sources), of which nine met the inclusion criteria. Of the nine included studies, five related to clinical aspects and four were laboratory studies. CONCLUSION: A number of new studies have provided further evidence for the mode of action of the antimicrobial effect of DACC-coated dressings and its wide spectrum effect (including World Health Organization-prioritised microorganisms). Additional clinical studies have provided evidence of new applications, such as in treating wounds in paediatric patients, and extended the evidence relating to their use in treating surgical site infections. Evidence also shows that DACC-coated wound dressings can aid in the binding of biofilms, and how this technology can align and support antimicrobial stewardship in the prevention of antimicrobial resistance.


Asunto(s)
Antiinfecciosos , Programas de Optimización del Uso de los Antimicrobianos , Humanos , Niño , Cloruros , Vendajes , Infección de la Herida Quirúrgica/prevención & control , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico
7.
Brain ; 146(12): 4826-4844, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37530487

RESUMEN

The dorsomedial prefrontal cortex/dorsal anterior cingulate cortex (dmPFC/dACC) is a brain area subject to many theories and debates over its function(s). Even its precise anatomical borders are subject to much controversy. In the past decades, the dmPFC/dACC has been associated with more than 15 different cognitive processes, which sometimes appear quite unrelated (e.g. body perception, cognitive conflict). As a result, understanding what the dmPFC/dACC does has become a real challenge for many neuroscientists. Several theories of this brain area's function(s) have been developed, leading to successive and competitive publications bearing different models, which sometimes contradict each other. During the last two decades, the lively scientific exchanges around the dmPFC/dACC have promoted fruitful research in cognitive neuroscience. In this review, we provide an overview of the anatomy of the dmPFC/dACC, summarize the state of the art of functions that have been associated with this brain area and present the main theories aiming at explaining the dmPFC/dACC function(s). We explore the commonalities and the arguments between the different theories. Finally, we explain what can be learned from these debates for future investigations of the dmPFC/dACC and other brain regions' functions.


Asunto(s)
Encéfalo , Giro del Cíngulo , Humanos , Corteza Prefrontal , Mapeo Encefálico , Aprendizaje , Imagen por Resonancia Magnética
8.
Surg Case Rep ; 9(1): 105, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37314669

RESUMEN

BACKGROUND: Necrotizing fasciitis in neonates is a rare and life-threatening infection involving necrosis of the skin, subcutaneous tissues, deep fascia, and sometimes underlying muscles, with a fulminant course and high mortality rate. Necrotizing fasciitis with gas gangrene related to infection of a peripherally inserted central catheter is very rare. CASE PRESENTATION: The patient was a full-term female neonate born by vaginal delivery. Following diagnosis of patent ductus arteriosus, indomethacin was administered from a peripherally inserted central catheter for 3 days. Four days after the termination of medical treatment for the patent ductus arteriosus, the patient developed fever and a severely elevated inflammatory response was identified from blood testing. Around the right anterior chest wall, corresponding to the site of the catheter tip, redness was increased and gas crepitus was felt under the skin. Computed tomography revealed emphysema in the anterior chest, in subcutaneous areas and between muscles. Emergency surgical debridement was performed under a diagnosis of necrotizing fasciitis with gas gangrene. With antibiotic treatment, we started to fill the wound with a dialkyl carbamoyl chloride-coated dressing and povidone-iodine sugar ointment after washing with saline once a day. The patient survived and after 3 weeks of treatment with the dressing, the wound had successfully resolved without motor impairments. CONCLUSIONS: In addition to medical treatment and prompt surgical debridement, we used dialkyl carbamoyl chloride-coated dressing and povidone-iodine sugar ointment for antiseptic dressings and successfully treated neonatal necrotizing fasciitis with gas gangrene caused by peripherally inserted central catheter infection with Citrobacter koseri.

9.
Brain Struct Funct ; 228(5): 1329-1345, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37219626

RESUMEN

Self-regulation, which is an individual's ability to control their emotions and behaviors in pursuit of goals, is a complex cognitive function that relies on distributed brain networks. Here, we used activation likelihood estimation (ALE) to conduct two large-scale meta-analyses of brain imaging studies of emotional regulation and behavioral regulation. We used single analysis of ALE to identify brain activation regions associated with behavioral regulation and emotion regulation. The conjunction results of the contrast analysis of the two domains showed that the crucial brain regions of dorsal anterior cingulate cortex (dACC), bilateral anterior insula (AI), and right inferior parietal lobule (IPL) are nested within the brain areas of the two regulation domains at the spatial and functional level. In addition, we assessed the coactivation pattern of the four common regions using meta-analytic connectivity modeling (MACM). The coactivation brain patterns based on the dACC and bilateral AI overlapped with the two regulation brain maps in a high proportion. Furthermore, the functional characters of the identified common regions were reverse-inferenced using the BrainMap database. Collectively, these results indicate that the brain regions of dACC and bilateral AI, playing a crucial role as a hub to other brain regions and networks by effective connectivity in self-regulation, are spatially nested in the brain network of behavioral regulation and emotion regulation.


Asunto(s)
Regulación Emocional , Giro del Cíngulo , Giro del Cíngulo/fisiología , Funciones de Verosimilitud , Encéfalo/fisiología , Emociones/fisiología , Mapeo Encefálico , Imagen por Resonancia Magnética
10.
Pharmacol Biochem Behav ; 225: 173544, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37004979

RESUMEN

Prefrontal and striatal glutamate plays an important role in modulating striatal dopamine levels and an imbalance in regional glutamate has been identified in several psychiatric conditions. We hypothesized that this imbalance also exists in cannabis use disorder (CUD). We recently quantified the difference in glutamate of dorsal anterior cingulate (dACC) and striatum regions in the frontostriatal pathway using proton MRS at baseline and on verified abstinent days 7 and 21 in chronic users of cannabis (n = 20) in comparison with age- and sex- matched non-using controls (n = 10). In addition, the Barratt Impulsiveness Scale-11 (BIS) was collected as a measure of inhibitory impulse control of the participants. We found that the difference in glutamate concentrations between the dACC and striatum (ΔdACC-strGlu) of the controls was significantly higher than that of cannabis users across the study timeline (F(1,28) = 18.32, p < 0.0005). The group difference was not affected by age, sex, or alcohol/cigarette consumption. On abstinent day 7, ΔdACC-strGlu was significantly correlated with the corresponding ΔdACC-strGABA among the users (r = 0.837, p < 0.00001). On day 21, ΔdACC-strGlu was negatively associated with monthly cannabis use days (Spearman's rho = -0.444, p = 0.05). Self-reported BIS and its subscales were significantly altered among the users compared to the controls across the study timeline (total F(1,28) = 7.0, p = 0.013; non-planning F(1,28) = 16.1, p < 0.0005; motor F(1,28) = 5.9, p = 0.022; cognitive F(1,28) = 6.1, p = 0.019). These data provide preliminary evidence that chronic cannabis use may lead to a dACC-striatal glutamate imbalance in conjunction with poor impulse control.


Asunto(s)
Cannabis , Alucinógenos , Humanos , Giro del Cíngulo/metabolismo , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Agonistas de Receptores de Cannabinoides , Ácido Glutámico/metabolismo , Imagen por Resonancia Magnética
11.
Microbiol Spectr ; 11(3): e0001423, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37098975

RESUMEN

Peptidoglycan (PG) is an essential bacterial architecture pivotal for shape maintenance and adaptation to osmotic stress. Although PG synthesis and modification are tightly regulated under harsh environmental stresses, few related mechanisms have been investigated. In this study, we aimed to investigate the coordinated and distinct roles of the PG dd-carboxypeptidases (DD-CPases) DacC and DacA in cell growth under alkaline and salt stresses and shape maintenance in Escherichia coli. We found that DacC is an alkaline DD-CPase, the enzyme activity and protein stability of which are significantly enhanced under alkaline stress. Both DacC and DacA were required for bacterial growth under alkaline stress, whereas only DacA was required for growth under salt stress. Under normal growth conditions, only DacA was necessary for cell shape maintenance, while under alkaline stress conditions, both DacA and DacC were necessary for cell shape maintenance, but their roles were distinct. Notably, all of these roles of DacC and DacA were independent of ld-transpeptidases, which are necessary for the formation of PG 3-3 cross-links and covalent bonds between PG and the outer membrane lipoprotein Lpp. Instead, DacC and DacA interacted with penicillin-binding proteins (PBPs)-dd-transpeptidases-mostly in a C-terminal domain-dependent manner, and these interactions were necessary for most of their roles. Collectively, our results demonstrate the coordinated and distinct novel roles of DD-CPases in bacterial growth and shape maintenance under stress conditions and provide novel insights into the cellular functions of DD-CPases associated with PBPs. IMPORTANCE Most bacteria have a peptidoglycan architecture for cell shape maintenance and protection against osmotic challenges. Peptidoglycan dd-carboxypeptidases control the amount of pentapeptide substrates, which are used in the formation of 4-3 cross-links by the peptidoglycan synthetic dd-transpeptidases, penicillin-binding proteins (PBPs). Seven dd-carboxypeptidases exist in Escherichia coli, but the physiological significance of their redundancy and their roles in peptidoglycan synthesis are poorly understood. Here, we showed that DacC is an alkaline dd-carboxypeptidase for which both protein stability and enzyme activity are significantly enhanced at high pH. Strikingly, dd-carboxypeptidases DacC and DacA physically interacted with PBPs, and these interactions were necessary for cell shape maintenance as well as growth under alkaline and salt stresses. Thus, cooperation between dd-carboxypeptidases and PBPs may allow E. coli to overcome various stresses and to maintain cell shape.


Asunto(s)
Peptidoglicano , Peptidil Transferasas , Proteínas de Unión a las Penicilinas/genética , Proteínas de Unión a las Penicilinas/metabolismo , Peptidoglicano/metabolismo , Escherichia coli , Carboxipeptidasas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
12.
Front Hum Neurosci ; 17: 990581, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36875235

RESUMEN

Introduction: A new line of insomnia research focuses on the developmental trajectories from early live stress to insomnia in adulthood. Adverse childhood experiences (ACE's) might create a vulnerability for later maladaptive coping with distress, as seen in chronic hyperarousal or insomnia. In an functional magnetic resonance imaging (fMRI) study, failure to dissociate the neurobiological components of shame from autobiographical shameful memories in insomnia was reflected by continued activation of the dorsal anterior cingulate cortex (dACC), which may be a result of maladaptive coping in the wake of ACE's. Following up on that study, the current pilot study explores the relation between ACE's, shame coping-styles, adult insomnia, hyperarousal, and neurobiology of autobiographical memory. Methods: We used existing data (N = 57) from individuals with insomnia (N = 27) and controls (N = 30), and asked these participants to complete the childhood trauma questionnaire (CTQ). Two structural equation models were used to test the hypotheses that shame-coping styles and insomnia symptom severity mediate the association between ACE's and (1) self-rated hyperarousal symptoms and (2) dACC activation to recall of autobiographical memories. Results: For the association between ACE's and hyperarousal, there was a significant mediation of shame-coping style (p < 0.05). This model also indicated worse shame coping with more ACE's (p < 0.05) and worse insomnia symptoms with more ACES's (p < 0.05), but no association between shame coping and insomnia symptoms (p = 0.154). In contrast, dACC activation to recall of autobiographical memories could only be explained by its direct association with ACE's (p < 0.05), albeit that in this model more ACE's were also associated with worse insomnia symptoms. Discussion: These findings could have an implication for the approach of treatment for insomnia. It could be focused more on trauma and emotional processing instead of conventional sleep interventions. Future studies are recommended to investigate the relationship mechanism between childhood trauma and insomnia, with additional factors of attachment styles, personality, and temperament.

13.
Molecules ; 28(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36677591

RESUMEN

Consumption of white rice (WR) has been shown to predispose individuals to metabolic disorders. However, brown rice (BR), which is relatively richer in bioactive compounds, possesses anti-glycaemic and antioxidant effects. In this study, fifteen cultivars of paddy rice that are predominantly consumed in North West Nigeria were analysed for their nutritional composition, bioactive contents and effects on metabolic outcomes in a fruit fly model. Gene expression analyses were conducted on the whole fly, targeting dPEPCK, dIRS, and dACC. The protein, carbohydrate, and fibre contents and bioactives of all BR cultivars were significantly different (p < 0.05) from the WR cultivars. Moreover, it was demonstrated that the glucose and trehalose levels were significantly higher (p < 0.05), while glycogen was significantly lower (p < 0.05) in the WR groups compared to the BR groups. Similarly, the expression of dACC and dPEPCK was upregulated, while that of dIRS was downregulated in the WR groups compared to the BR groups. Sex differences (p < 0.05) were observed in the WR groups in relation to the nutrigenomic effects. Our findings confirm metabolic perturbations in fruit flies following consumption of WR via distortion of insulin signalling and activation of glycogenolysis and gluconeogenesis. BR prevented these metabolic changes possibly due to its richer nutritional composition.


Asunto(s)
Enfermedades Metabólicas , Oryza , Glucemia/metabolismo , Insulina/metabolismo , Nutrigenómica , Oryza/química , Drosophila , Animales
14.
Int J Psychophysiol ; 183: 1-8, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36122824

RESUMEN

Individuals with high intolerance of uncertainty (IU) tend to display maladaptive cognitive, behavioral, physiological, and/or neural responses during anticipation of uncertain or ambiguous outcomes, both positive and negative in valence. Importantly, high IU has been proposed as a key transdiagnostic phenotypic risk factor for the onset and maintenance of several psychiatric disorders. Within the context of reward processing, high IU has been related to dysfunctional reward anticipation, which may be mediated by hyperactive anterior insula (AIC) response to uncertainty. The present study further investigated the relationship between the AIC and IU by examining the association between individual differences in IU and task-based functional connectivity of the right AIC using functional magnetic resonance imaging (fMRI). Participants (N = 171) completed a self-report measure of IU and a reward anticipation task during fMRI. Generalized psychophysiological interaction (gPPI) analyses were performed with a seed in the right AIC. In the U-threat model, we found that greater self-reported levels of IU were correlated with increased functional connectivity between the right AIC and the dorsal anterior cingulate cortex (dACC) and the right dorsolateral prefrontal cortex (dlPFC). In the P-threat model, we did not find these associations, perhaps indicating that they may be more robust during uncertainty. These preliminary findings suggest that parts of salience and central executive control networks may be impacted by and underlie the expression of IU. Future studies should examine the generalizability of these findings to clinical populations and investigate how disruption of these functional networks may contribute to psychopathology.


Asunto(s)
Giro del Cíngulo , Trastornos Mentales , Humanos , Incertidumbre , Giro del Cíngulo/diagnóstico por imagen , Cognición , Recompensa , Imagen por Resonancia Magnética , Anticipación Psicológica/fisiología
15.
J Wound Care ; 31(7): 560-570, 2022 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-35797260

RESUMEN

OBJECTIVE: Wound dressings that inactivate or sequestrate microorganisms, such as those with a hydrophobic, bacteria-binding dialkylcarbamoyl chloride (DACC) surface, can reduce the risk of clinical infections. This 'passive' bioburden control, avoiding bacterial cell wall disruption with associated release of bacterial endotoxins aggravating inflammation, is advantageous in hard-to-heal wounds. Hence, the full scope of DACC dressings, including the potential impact of higher inoculum densities, increased protein load and different pH on antibacterial activity, needs to be evaluated. METHOD: The Japanese Industrial Standard (JIS) L 1902 challenge test was used to evaluate the antimicrobial activity of the DACC-coated dressing against several World Health Organization (WHO)-prioritised wound pathogens (e.g., meticillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, microorganisms with extended-spectrum beta-lactamases and Acinetobacter baumannii), the effect of repeated bacterial challenge in an adverse wound environment, and antimicrobial performance at wound-related pH. RESULTS: High antibacterial activity of the DACC-coated dressing against the WHO-prioritised bacteria strains by its irreversible binding and inhibition of growth of bound bacteria was confirmed using JIS L 1902. At increased inoculation densities, compared to standard conditions, the DACC-coated dressing still achieved strong-to-significant antibacterial effects. Augmenting the media protein content also affected antibacterial performance; a 0.5-1 log reduction in antibacterial activity was observed upon addition of 10% fetal calf serum. The pH did not influence antibacterial performance. The DACC-coated dressing also sustained antibacterial activity over subsequent reinfection steps. CONCLUSION: It can be assumed that the DACC-coated dressing exerts beneficial effects in controlling the wound bioburden, reducing the overall demand placed on antibiotics, without using antimicrobial substances.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Infección de Heridas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Bacterias , Vendajes/microbiología , Cloruros , Humanos , Infección de Heridas/microbiología , Infección de Heridas/terapia
16.
J Wound Care ; 31(6): 502-509, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35678791

RESUMEN

OBJECTIVE: Endotoxin causes inflammation and can impair wound healing. Conventional methods that reduce bioburden in wounds by killing microorganisms using antibiotics, topical antimicrobials or antimicrobial dressings may induce endotoxin release from Gram-negative bacteria. Another approach is to reduce bioburden by adsorbing microorganisms, without killing them, using dialkylcarbamoyl chloride (DACC)-coated wound dressings. This study evaluated the endotoxin-binding ability of a DACC-coated wound dressing (Sorbact Compress, Abigo Medical AB, Sweden) in vitro, including its effect on the level of natural endotoxin released from Gram-negative bacteria. METHOD: Different concentrations of purified Pseudomonas aeruginosa endotoxin and a DACC-coated dressing were incubated at 37°C for various durations. After incubation, the dressing was removed and endotoxin concentration in the solution was quantified using a Limulus amebocyte lysate (LAL) assay. The DACC-coated dressing was also incubated with Pseudomonas aeruginosa cells for one hour at 37°C. After incubation, the dressing and bacterial cells were removed and shed endotoxin remaining in the solution was quantified. RESULTS: Overnight incubation of the DACC-coated wound dressing with various concentrations of purified Pseudomonas aeruginosa endotoxin (96-11000 EU/ml) consistently and significantly reduced levels of free endotoxin by 93-99% (p<0.0001). A significant endotoxin reduction of 39% (p<0.001) was observed after five minutes. The DACC-coated dressing incubated with clinically relevant Pseudomonas aeruginosa cells also reduced shed endotoxin by >99.95% (p<0.0001). CONCLUSION: In this study, we showed that a DACC-coated wound dressing efficiently and rapidly binds both purified and shed endotoxin from Pseudomonas aeruginosa in vitro. This ability to remove both endotoxin and bacterial cells could promote the wound healing process.


Asunto(s)
Antiinfecciosos Locales , Infección de Heridas , Antibacterianos/farmacología , Vendajes/microbiología , Cloruros , Endotoxinas , Humanos , Pseudomonas aeruginosa , Cicatrización de Heridas , Infección de Heridas/prevención & control
17.
Front Aging Neurosci ; 14: 763494, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35370625

RESUMEN

According to the inhibition deficit hypothesis, the ability to inhibit unwanted or irrelevant thoughts and behaviors decreases with age, which can have a significant impact on cognitive and emotional processing. However, studies examining inhibition and age have shown mixed results, with some studies finding a decrease in inhibitory control as individuals age, while others have found no relationship. The goal of this proof-of-concept study was to examine the underlying neural mechanisms that may explain why some older adults are better than others at inhibitory control by investigating the relationship between resting-state functional connectivity (rsFC) of the salience network, a network critical for detecting and focusing attention toward relevant stimuli while ignoring irrelevant information in the environment, and a behavioral measure of inhibitory control (Stroop Task interference score) in a sample of 65 healthy older individuals (ages 65+). Results revealed no direct effect of age on Stroop performance; however, there was an indirect effect of age on Stroop performance through rsFC. These results suggest that rsFC of the salience network may be an important factor to consider when it comes to understanding individual differences in inhibitory control behavior among older adults.

18.
Front Psychol ; 13: 743178, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35242072

RESUMEN

According to the conflict monitoring hypothesis, conflict monitoring and inhibitory control in cognitive control mainly cause activity in the anterior cingulate cortex (ACC) and control-related prefrontal cortex (PFC) in many cognitive tasks. However, the role of brain regions in the default mode network (DMN) in cognitive control during category induction tasks is unclear. To test the role of the ACC, PFC, and subregions of the DMN elicited by cognitive control during category induction, a modified category induction task was performed using simultaneous fMRI scanning. The results showed that the left middle frontal gyrus (BA9) and bilateral dorsal ACC/medial frontal gyrus (BA8/32) were sensitive to whether conflict information (with/without) appears, but not to the level of conflict. In addition, the bilateral ventral ACC (BA32), especially the right vACC, a part of the DMN, showed significant deactivation with an increase in cognitive effort depending on working memory. These findings not only offer further evidence for the important role of the dorsolateral PFC and dorsal ACC in cognitive control during categorization but also support the functional distinction of the dorsal/ventral ACC in the category induction task.

19.
J Neurosci ; 42(7): 1275-1291, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-34907025

RESUMEN

The dorsal anterior cingulate cortex (dACC) plays a critical role in cognitive control over different domains of tasks. The dACC activities uniformly represent task-generic intensities of control signals across different tasks. However, it remains unclear whether the dACC activities could also encode task identities of control signals across different tasks. If so, how the two types of control information are coherently organized in the dACC? Decision uncertainty is an internally-generated control signal by retrospective monitoring, namely, metacognition, even with no external feedback. We here investigated neural representations of decision uncertainty accompanying three decision-making tasks in the domains of perception, rule-based inference, and memory using trial-by-trial univariate and multivariate analyses on functional magnetic resonance imaging (fMRI) data acquired on human male and female healthy subjects. Our results demonstrated that the dACC represented decision uncertainty commonly across the three decision-making tasks. Further, the multivariate fMRI analyses revealed a mosaic form of neural representations of decision uncertainty across tasks in the dACC. The identity and intensity information was separately represented in two dissociable components, the high-dimensional pattern and the scalar magnitude, of the dACC multivoxel fMRI activities. Lastly, a follow-up behavioral experiment confirmed that this mosaic form of neural representations of parallelly existing decision uncertainty across different tasks should lead to mutual interferences more on the intensity, but less on the identity of control signals. Thus, our findings suggest that the dACC with the mosaic form of neural representations could provide task-generic and task-specific metacognitive control signals to guide appropriate control on different decision-making tasks.SIGNIFICANCE STATEMENT Metacognition is a form of cognitive control using internally generated decision uncertainty to guide behavior adjustment with no needs of external feedback. Decision uncertainty as a generalizable control signal is commonly encoded in the human dorsal anterior cingulate cortex (dACC) accompanying different decision-making tasks. It remains unknown whether or not the task-specific control information is represented in the dACC. We here revealed that multivoxel functional magnetic resonance imaging (fMRI) activities associated with decision uncertainty in the dACC concurrently represented the identity and intensity information. The mixtures of neural representations of decision uncertainty across different tasks should cause specific interferences on each other. Hence, the neural representations of control signals in the human dACC should be task-generic and task-specific.


Asunto(s)
Toma de Decisiones/fisiología , Giro del Cíngulo/fisiología , Metacognición/fisiología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino
20.
NIHR Open Res ; 2: 59, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36825217

RESUMEN

Background: Buruli ulcer (BU) can lead to disfiguring ulcers and permanent disability. The 2030 World Health Organization (WHO) road map for Neglected Tropical Diseases (NTDs) calls for major scaling up in diagnosis and management to eliminate disability due to the disease. Current treatment for BU is with daily oral rifampicin (10mg/kg dose) and clarithromycin (15mg/kg dose) for eight weeks, combined with standard gauze wound dressings. Dialkylcarbamoyl chloride (DACC)-coated dressings have been shown to irreversibly bind bacteria on wound surfaces resulting in their removal when dressings are changed. This trial aims to determine whether combining a high-dose oral rifampicin regimen with DACC dressings can improve the rate of wound healing relative to standard-dose oral rifampicin combined with DACC dressings. Methods: This is an individual, multi-centre Phase 3 randomised controlled trial, which will be conducted in three clinical sites in Ghana. The primary outcome measure will be the mean time to clearance of viable mycobacteria. Cost and health-related quality of life data will be collected, and a cost-effectiveness analysis will be performed. Discussion: The findings from this trial could lead to a change in how BU is treated. A shorter but more efficacious regimen would lead to improved treatment outcomes and potentially substantial financial and economic savings. Trial registration: Pan African Clinical Trials Repository (registration number; PACTR202011867644311). Registered on 30 th November 2020.


Buruli ulcer (BU), caused by Mycobacterium ulcerans, manifests clinically as a wound or swelling. There are several approaches for managing this condition. One is the availability of two antibiotics, usually rifampicin in combination with clarithromycin, that can be used to treat the disease. Rifampicin is thought to be the most important of these two drugs. Scientists have found out that a higher dose of rifampicin is safe and may help improve healing outcome and shorten the duration of treatment. Individuals with BU wounds also go through wound dressing procedures at their hospitals and health centres. Commonly, wounds are dressed using Vaseline gauze and bandages. However, it has been observed that some affected individuals heal faster than others even with the antibiotic treatment. Some still have living organisms in their wounds many weeks after the antibiotic treatment. There is a new dressing material called DACC which is believed to permanently bind bacteria on the wound surface leading to their removal when the dressings are changed. This may be a good way to treat and prevent infection without the use of more drugs. This study aims to determine whether combining a high-dose oral rifampicin regimen with DACC dressings can improve the rate of wound healing relative to standard-dose oral rifampicin combined with DACC dressings. Furthermore, cost and health-related quality of life data will be collected and a cost-effectiveness analysis will be performed. The findings from this trial could lead to a change in how BU is treated. A shorter but more efficacious regimen would lead to improved treatment outcomes and potentially substantial financial and economic savings.

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