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General Psychiatry 2024Structural imaging holds great potential for precise targeting and stimulation for deep brain stimulation (DBS). The anatomical information it provides may serve as...
Presurgical structural imaging and clinical outcome in combined bed nucleus of the stria terminalis-nucleus accumbens deep brain stimulation for treatment-resistant depression.
BACKGROUND
Structural imaging holds great potential for precise targeting and stimulation for deep brain stimulation (DBS). The anatomical information it provides may serve as potential biomarkers for predicting the efficacy of DBS in treatment-resistant depression (TRD).
AIMS
The primary aim is to identify preoperative imaging biomarkers that correlate with the efficacy of DBS in patients with TRD.
METHODS
Preoperative imaging parameters were estimated and correlated with the 6-month clinical outcome of patients with TRD receiving combined bed nucleus of the stria terminalis (BNST)-nucleus accumbens (NAc) DBS. White matter (WM) properties were extracted and compared between the response/non-response and remission/non-remission groups. Structural connectome was constructed and analysed using graph theory. Distances of the volume of activated tissue (VAT) to the main modulating tracts were also estimated to evaluate the correlations.
RESULTS
Differences in fibre bundle properties of tracts, including superior thalamic radiation and reticulospinal tract, were observed between the remission and non-remission groups. Distance of the centre of the VAT to tracts connecting the ventral tegmental area and the anterior limb of internal capsule on the left side varied between the remission and non-remission groups (p=0.010, t=3.07). The normalised clustering coefficient (γ) and the small-world property (σ) in graph analysis correlated with the symptom improvement after the correction of age.
CONCLUSIONS
Presurgical structural alterations in WM tracts connecting the frontal area with subcortical regions, as well as the distance of the VAT to the modulating tracts, may influence the clinical outcome of BNST-NAc DBS. These findings provide potential imaging biomarkers for the DBS treatment for patients with TRD.
PubMed: 38912307
DOI: 10.1136/gpsych-2023-101210 -
NMC Case Report Journal 2024Superficial siderosis (SS) of the central nervous system is a rare disorder that is caused by chronic or recurrent hemorrhage in the subarachnoid space via a dural...
Superficial siderosis (SS) of the central nervous system is a rare disorder that is caused by chronic or recurrent hemorrhage in the subarachnoid space via a dural defect at the spinal level. The most common clinical features of SS include slow-progressive sensorineural deafness, cerebellar symptoms, and pyramidal tract signs. Considering that SS can present with broad clinical manifestations, for precise diagnosis, this disease must be understood. Anti-Ro/SSA antibodies are commonly detected in patients with Sjögren's syndrome and are utilized as markers for autoimmune diseases. In this report, we present a unique pathological condition in which SS coincided with a positive anti-Ro/SSA antibody test result. During the diagnosis of gait disturbance, an elevation in anti-Ro/SSA antibody was detected, and steroid pulse therapy was initiated as the initial treatment for autoimmune diseases. Head magnetic resonance imaging (MRI) revealed extensive hypointensity as a dark band that surrounded the intracranial basal structures and cerebellar hemispheres. Spinal MRI indicated ventral longitudinal intraspinal fluid collection extending from C7 to T5 as well as a defect in the ventral T2-3 dura mater. Intraoperative visualization revealed that the intradural venous plexus was the source of bleeding that caused the SS. To our knowledge, this report is the first to discuss the presence of anti-Ro/SSA antibodies in patients with SS. The role of anti-Ro/SSA antibodies in the pathophysiology of SS remains unclear; therefore, to confirm a possible association, further research and accumulation of cases are required.
PubMed: 38911924
DOI: 10.2176/jns-nmc.2023-0214 -
Annals of Surgery Open : Perspectives... Jun 2024We aimed to evaluate the prevalence of highly detailed ventral hernia repair (VHR) operative reports and associations between operative report detail and postoperative...
OBJECTIVE
We aimed to evaluate the prevalence of highly detailed ventral hernia repair (VHR) operative reports and associations between operative report detail and postoperative outcomes in a medico-legal dataset.
BACKGROUND
VHR are one of the most common surgical procedures performed in the United States. Previous work has shown that VHR operative reports are poorly detailed, however, the relationship between operative report detail and patient outcomes is unknown.
METHODS
This is a retrospective cross-sectional observational study. Operative reports describing VHR were obtained from a medical-legal database. Medical records were screened and data was extracted including clinical outcomes, such as surgical site infection (SSI), hernia recurrence, and reoperation and the presence of key details in each report. Highly detailed operative reports were defined as having 70% of recommended details. The primary outcome was the prevalence of highly detailed VHR operative reports.
RESULTS
A total of 1011 VHR operative reports dictated by 693 surgeons across 517 facilities in 50 states were included. Median duration of follow-up was 4.6 years after initial surgery. Only 35.7% of operative reports were highly detailed. More recent operative reports, cases with resident involvement, and contaminated procedures were more likely to be highly detailed (all < 0.05). Compared to poorly detailed operative reports, cases with highly detailed reports had fewer SSIs (13.2% vs 7.5%, = 0.006), hernia recurrence (65.8% vs 55.4%, = 0.002), and reoperation (78.9% vs 62.6%, = 0.001).
CONCLUSIONS
In this medico-legal dataset, most VHR operative reports are poorly detailed while highly detailed operative reports were associated with lower rates of complications. Future studies should examine a nationally representative dataset to validate our findings.
PubMed: 38911660
DOI: 10.1097/AS9.0000000000000425 -
Neurobiology of Language (Cambridge,... 2024Reading is both a visual and a linguistic task, and as such it relies on both general-purpose, visual mechanisms and more abstract, meaning-oriented processes....
Reading is both a visual and a linguistic task, and as such it relies on both general-purpose, visual mechanisms and more abstract, meaning-oriented processes. Disentangling the roles of these resources is of paramount importance in reading research. The present study capitalizes on the coupling of fast periodic visual stimulation and MEG recordings to address this issue and investigate the role of different kinds of visual and linguistic units in the visual word identification system. We compared strings of pseudo-characters; strings of consonants (e.g., sfcl); readable, but unattested strings (e.g., amsi); frequent, but non-meaningful chunks (e.g., idge); suffixes (e.g., ment); and words (e.g., vibe); and looked for discrimination responses with a particular focus on the ventral, occipito-temporal regions. The results revealed sensitivity to alphabetic, readable, familiar, and lexical stimuli. Interestingly, there was no discrimination between suffixes and equally frequent, but meaningless endings, thus highlighting a lack of sensitivity to semantics. Taken together, the data suggest that the visual word identification system, at least in its early processing stages, is particularly tuned to form-based regularities, most likely reflecting its reliance on general-purpose, statistical learning mechanisms that are a core feature of the visual system as implemented in the ventral stream.
PubMed: 38911459
DOI: 10.1162/nol_a_00145 -
Neurobiology of Language (Cambridge,... 2024Language processing relies on the communication between brain regions that is achieved through several white matter tracts, part of the dorsal, ventral, and medial...
Language processing relies on the communication between brain regions that is achieved through several white matter tracts, part of the dorsal, ventral, and medial pathways involved in language processing and control (Coggins et al., 2004; Friederici & Gierhan, 2013; Hickok & Poeppel, 2007; Luk et al., 2011). While changes in white matter tract morphology have been reported as a function of second language learning in bilinguals, little is known about changes that may be present in multilanguage users. Here we investigate white matter morphometry in a group of highly proficient multilinguals, (individuals with proficiency in four or more languages), compared to a group of monolinguals. White matter morphometry was quantified using a fixel-based analysis (Raffelt et al., 2015; Raffelt et al., 2017; Tournier et al., 2007). Higher fiber cross-section and lower fiber density values were observed for the multilinguals, in the dorsal pathways (superior longitudinal fasciculus and arcuate fasciculus) and the ventral pathway, including the inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, and the uncinate fasciculus. Segments of the corpus callosum, the fornix, and the cortico-spinal tract showed decreases in all three morphometry measures for multilinguals. The findings suggest differential efficiencies in neural communication between domain-specific language regions and domain-general cognitive processes underlying multilingual language use. We discuss the results in relation to the bilingual Anterior to Posterior and Subcortical Shift (BAPSS) hypothesis (Grundy et al., 2017) and the Dynamic Restructuring Model (Pliatsikas, 2020).
PubMed: 38911457
DOI: 10.1162/nol_a_00144 -
Cureus May 2024We report a case of a 76-year-old female presenting with intermittent obscure gastrointestinal (GI) bleeding originating from the small intestine secondary to a delayed...
We report a case of a 76-year-old female presenting with intermittent obscure gastrointestinal (GI) bleeding originating from the small intestine secondary to a delayed complication related to mesh hernioplasty. The mesh was eroding into the small bowel causing intermittent transfusion-dependent GI bleeding. Multiple upper and lower endoscopic investigations were sought over the last two years, but they were noncontributory. Finally, video capsule endoscopy (VCE) revealed mesh invasion into the small bowel wall associated with bleeding. This case emphasizes the significance of an early sufficient differential diagnosis in patients with obscure GI bleeding. Meanwhile, being cognizant of rare causes of GI bleeding in patients who have had hernioplasty is very important.
PubMed: 38910789
DOI: 10.7759/cureus.60908 -
Nature Communications Jun 2024Metacognitive evaluations of confidence provide an estimate of decision accuracy that could guide learning in the absence of explicit feedback. We examine how humans...
Metacognitive evaluations of confidence provide an estimate of decision accuracy that could guide learning in the absence of explicit feedback. We examine how humans might learn from this implicit feedback in direct comparison with that of explicit feedback, using simultaneous EEG-fMRI. Participants performed a motion direction discrimination task where stimulus difficulty was increased to maintain performance, with intermixed explicit- and no-feedback trials. We isolate single-trial estimates of post-decision confidence using EEG decoding, and find these neural signatures re-emerge at the time of feedback together with separable signatures of explicit feedback. We identified these signatures of implicit versus explicit feedback along a dorsal-ventral gradient in the striatum, a finding uniquely enabled by an EEG-fMRI fusion. These two signals appear to integrate into an aggregate representation in the external globus pallidus, which could broadcast updates to improve cortical decision processing via the thalamus and insular cortex, irrespective of the source of feedback.
Topics: Humans; Decision Making; Male; Magnetic Resonance Imaging; Female; Adult; Basal Ganglia; Young Adult; Learning; Electroencephalography; Brain Mapping
PubMed: 38909014
DOI: 10.1038/s41467-024-49538-w -
Neurobiology of Learning and Memory Jun 2024The ability to learning and remember, which is fundamental for behavioral adaptation, is susceptible to stressful experiences during the early postnatal period, such as...
The ability to learning and remember, which is fundamental for behavioral adaptation, is susceptible to stressful experiences during the early postnatal period, such as abnormal levels of maternal care. The exact mechanisms underlying these effects still remain elusive. This study examined in male mice whether early life stress (ELS) alters memory and brain activation patterns, by studying the expression of the immediate early genes (IEGs) c-Fos and Arc in the dentate gyrus (DG) and basolateral amygdala (BLA) after training and memory retrieval in a fear conditioning task. Furthermore, we examined the potential of RU38486 (RU486), a glucocorticoid receptor antagonist, to mitigate ELS-induced memory deficits by blocking stress signalling during adolescence. Arc::dVenus reporter mice, which allow investigating experience-dependent expression of the immediate early gene Arc also at more remote time points, were exposed to ELS by housing dams and offspring with limited bedding and nesting material (LBN) between postnatal days (PND) 2-9 and trained in a fear conditioning task at adult age. We found that ELS reduced both fear acquisition and contextual memory retrieval. RU486 did not prevent these effects. ELS reduced the number of Arc::dVenus cells in DG and BLA after training, while the number of c-Fos cells were left unaffected. After memory retrieval, ELS decreased c-Fos cells in the ventral DG and BLA. ELS also disrupted the colocalization of c-Fos cells with (training activated) Arc::dVenus cells in the ventral DG, possibly indicating impaired engram allocation in the ventral DG after memory retrieval. Altered correlated activity during training and changes in IEG expression over time were also found in ELS animals. In conclusion, this study shows that ELS alters neuronal activation patterns after fear acquisition and retrieval, which may provide mechanistic insights into enduring impact of early-life stress on the processing of fear memories, possibly via changes in cell (co-) activation and engram cell allocation.
PubMed: 38906243
DOI: 10.1016/j.nlm.2024.107952 -
Cell Reports Jun 2024Planarian flatworms undergo continuous internal turnover, wherein old cells are replaced by the division progeny of adult pluripotent stem cells (neoblasts). How cell...
Planarian flatworms undergo continuous internal turnover, wherein old cells are replaced by the division progeny of adult pluripotent stem cells (neoblasts). How cell turnover is carried out at the organismal level remains an intriguing question in planarians and other systems. While previous studies have predominantly focused on neoblast proliferation, little is known about the processes that mediate cell loss during tissue homeostasis. Here, we use the planarian epidermis as a model to study the mechanisms of cell removal. We established a covalent dye-labeling assay and image analysis pipeline to quantify the cell turnover rate in the planarian epidermis. Our findings indicate that the ventral epidermis is highly dynamic and epidermal cells undergo internalization via basal extrusion, followed by a relocation toward the intestine and ultimately digestion by intestinal phagocytes. Overall, our study reveals a complex homeostatic process of cell clearance that may generally allow planarians to catabolize their own cells.
PubMed: 38906148
DOI: 10.1016/j.celrep.2024.114305 -
MedRxiv : the Preprint Server For... May 2024Deep brain stimulation is a viable and efficacious treatment option for dystonia. While the internal pallidum serves as the primary target, more recently, stimulation of...
Deep brain stimulation is a viable and efficacious treatment option for dystonia. While the internal pallidum serves as the primary target, more recently, stimulation of the subthalamic nucleus (STN) has been investigated. However, optimal targeting within this structure and its complex surroundings have not been studied in depth. Indeed, multiple historical targets that have been used for surgical treatment of dystonia are directly adjacent to the STN. Further, multiple types of dystonia exist, and outcomes are variable, suggesting that not all types would profit maximally from the exact same target. Therefore, a thorough investigation of the neural substrates underlying effects on dystonia symptoms is warranted. Here, we analyze a multi-center cohort of isolated dystonia patients with subthalamic implantations ( = 58) and relate their stimulation sites to improvement of appendicular and cervical symptoms as well as blepharospasm. Stimulation of the ventral oral posterior nucleus of thalamus and surrounding regions was associated with improvement in cervical dystonia, while stimulation of the dorsolateral STN was associated with improvement in limb dystonia and blepharospasm. This dissociation was also evident for structural connectivity, where the cerebellothalamic, corticospinal and pallidosubthalamic tracts were associated with improvement of cervical dystonia, while hyperdirect and subthalamopallidal pathways were associated with alleviation of limb dystonia and blepharospasm. Importantly, a single well-placed electrode may reach the three optimal target sites. On the level of functional networks, improvement of limb dystonia was correlated with connectivity to the corresponding somatotopic regions in primary motor cortex, while alleviation of cervical dystonia was correlated with connectivity to the recently described 'action-mode' network that involves supplementary motor and premotor cortex. Our findings suggest that different types of dystonia symptoms are modulated via distinct networks. Namely, appendicular dystonia and blepharospasm are improved with modulation of the basal ganglia, and, in particular, the subthalamic circuitry, including projections from the primary motor cortex. In contrast, cervical dystonia was more responsive when engaging the cerebello-thalamo-cortical circuit, including direct stimulation of ventral thalamic nuclei. These findings may inform DBS targeting and image-based programming strategies for patient-specific treatment of dystonia.
PubMed: 38903109
DOI: 10.1101/2024.05.24.24307896