Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 87
Filtrar
1.
Sci Data ; 11(1): 353, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589407

RESUMEN

Diffusion-weighted MRI (dMRI) is a widely used neuroimaging modality that permits the in vivo exploration of white matter connections in the human brain. Normative structural connectomics - the application of large-scale, group-derived dMRI datasets to out-of-sample cohorts - have increasingly been leveraged to study the network correlates of focal brain interventions, insults, and other regions-of-interest (ROIs). Here, we provide a normative, whole-brain connectome in MNI space that enables researchers to interrogate fiber streamlines that are likely perturbed by given ROIs, even in the absence of subject-specific dMRI data. Assembled from multi-shell dMRI data of 985 healthy Human Connectome Project subjects using generalized Q-sampling imaging and multispectral normalization techniques, this connectome comprises ~12 million unique streamlines, the largest to date. It has already been utilized in at least 18 peer-reviewed publications, most frequently in the context of neuromodulatory interventions like deep brain stimulation and focused ultrasound. Now publicly available, this connectome will constitute a useful tool for understanding the wider impact of focal brain perturbations on white matter architecture going forward.


Asunto(s)
Conectoma , Sustancia Blanca , Humanos , Encéfalo/diagnóstico por imagen , Conectoma/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Neuroimagen , Sustancia Blanca/diagnóstico por imagen
2.
Int J Biol Macromol ; 253(Pt 8): 127569, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37865362

RESUMEN

Eutroplus suratensis (Pearl spot) is naturally found in estuarine environments and has been noted to have a high salinity tolerance. By examining the impact of various salinity levels on the growth and survival of pearl spot, the present study aims to enhance aquaculture profitability by assessing their adaptability and physiological adjustments to changes in salinity and determining their potential to acclimate to a broad range of salinity regimes. Results revealed no mortality in the control group (0 ppt), and in 15, 25 and 35 ppt treatment groups. However, the remaining groups (45, 60, and 75 ppt) showed differing levels of mortality with 44 % mortality observed in the 45 ppt group and 100 % mortality in both the 60 and 75 ppt groups. The expression analysis showed that liver IGF-1 mRNA expression increased by 2.6-fold at 15 ppt, and HSP70 mRNA expression in the liver also showed a significant increase with rising salinity levels. In addition, OSTF1 expression exhibited an increase at 15 ppt, whereas SOD and CAT expression reached their highest levels at 25 ppt. At 15 ppt, the expression of NKA mRNA increased significantly by 2.8-fold. The study's overall findings suggested that utilizing a salinity level of 15 ppt for pearl spot production could be viable for profitable aquaculture.


Asunto(s)
Cíclidos , Salinidad , Animales , Adaptación Fisiológica/genética , Perfilación de la Expresión Génica , ARN Mensajero/genética
3.
Anim Biotechnol ; 34(4): 1553-1565, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35259071

RESUMEN

DNA barcoding, primarily focusing on cytochrome c oxidase subunit I (COI) gene has been appraised as an effective tool for species identification. In this study, we focused on the marine fishes of Family Nemipteridae, one of the commercially important group distributed within the Coromandel Coast. The Partial sequences of COI and 16S rRNA of mitochondrial genes were analyzed for species identification and phylogenetic relationship of Nemipterus species (Nemipterus japonicus, Nemipterus peronii, Nemipterus bipunctatus, Nemipterus bathybius). Character-based identification approaches that categorize specimens to species using classification rules that compactly identify species in terms of key diagnostic nucleotides in selected gene sequences. Using the BLOG 2.0 software, species-specific diagnostic nucleotides were identified for the selected group of species. A data set of 198 mtCOI sequences was obtained from published resources and used to screen character-based molecular diagnostic keys for species in silico. Partial sequences of both the genes provided sufficient phylogenetic information to distinguish the four Nemipterus species indicating the usefulness of mtDNA-based approach in species identification. This study proves the use of mtDNA genes sequence-based approach is a support tool along with traditional taxonomy for identifying fish species at a faster pace.


Asunto(s)
Peces , Genes Mitocondriales , Animales , Genes Mitocondriales/genética , Filogenia , ARN Ribosómico 16S/genética , Peces/genética , ADN Mitocondrial/genética , India , Nucleótidos
4.
Biol Trace Elem Res ; 201(3): 1451-1458, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35445936

RESUMEN

The present study focuses on the green synthesis of iron nanoparticles using plant extracts as reducing, capping, and stabilizing agents. Aqueous seaweed extracts with the addition of iron solution were mixed using a magnetic stirrer which resulted in a color change indicating the formation of iron nanoparticles. The iron nanoparticles were successfully synthesized using Sargassum wightii extract. The synthesized iron nanoparticles were characterized by UV-Vis spectrophotometer, Fourier transform infrared spectroscopy (FTIR), and zeta potential techniques. The UV-Vis spectra showed a peak at 412 to 415 nm. Zeta potential revealed that the synthesized iron nanoparticles were negative and positive charges. FTIR spectroscopy analysis showed the presence of chemical bond and amide group likely to be responsible for the green synthesis of iron nanoparticles. The effect of nano-iron as a dietary iron source on the growth and serum biochemical profile of Etroplus suratensis fingerlings was evaluated. Iron nanoparticles were fed to E. suratensis fingerlings for 60 days with two levels 10 mg (T1) and 20 mg (T2) and a control group without iron nanoparticles. The highest WG% and SGR and lowest FCR were observed in the T2 group which is significantly different (p < 0.05) from other groups. The serum biochemical profile showed significantly increased activity on 20 mg/kg of nano-iron-supplemented diet. The findings of the present study concluded that supplementation of nano-iron at the 20 mg/kg level to the regular fish diet has a better impact not only on growth but also on the overall health of the fish.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Sargassum , Animales , Sargassum/química , Nanopartículas/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas del Metal/química , Tecnología Química Verde/métodos
5.
J Therm Biol ; 110: 103370, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36462867

RESUMEN

Diabetic Foot Syndrome (DFS) is the prime impetus for most of the lower extremity complications among the diabetic subjects. DFS is characterized by aberrant variations in plantar foot temperature distribution while healthy subjects exhibit a symmetric thermal pattern between the contralateral and ipsilateral plantar feet. Thus, "asymmetry analysis" of foot thermal distribution is contributory in assessment of overall foot health of diabetic subjects. The study, aims to classify symmetric and asymmetric foot regions angiosome-wise, by comparing minimal number of color image features - color moments and Dissimilarity Index. Further, the asymmetric foot regions are assessed for identifying the hotspots within such angiosomes of the patients that characterize the possibility of onset of diabetic foot ulcer. The color feature based machine learning model developed, achieved an accuracy of 98% for a 10-fold cross validation, test accuracy of 96.07% and 0.96 F1-score thereby convincing that the chosen features are amplest and conducive in the asymmetry analysis. The developed model was validated for generalization by testing on a public benchmark dataset, in which the model achieved 92.5% accuracy and 0.91 F1 score.


Asunto(s)
Diabetes Mellitus Tipo 2 , Pie Diabético , Humanos , Pie Diabético/diagnóstico por imagen , Termografía , Pie , Aprendizaje Automático
6.
Arch Microbiol ; 204(11): 685, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36319873

RESUMEN

For the last 3 decades the shrimp industries has been plagued by many destructive diseases, which have resulted in severe production and economic losses to many aquaculture countries. These include viral, bacterial and parasitic diseases. Recently, another emerging viral disease is threatening the shrimp culture industry in Asia. The virus originally called Cherax quadricarinatus iridovirus (CQIV) or Shrimp hemocyte iridescent virus (SHIV) and now classified within the proposed genus Decapodiridovirus and formally named as Decapod iridescent virus 1 (DIV1) by International Committee on Taxonomy of Viruses (ICTV). The virus was first detected as early as 2014 from Cherax quadricarinatus samples in Fujian Province and farmed white leg shrimp Penaeus vannamei samples from Zhejiang Province. This review article encompasses the significance of the DIV1 and their implications for the future of the global aquaculture.


Asunto(s)
Iridoviridae , Penaeidae , Virosis , Animales , Acuicultura , Alimentos Marinos
7.
ACS Pharmacol Transl Sci ; 5(11): 1062-1069, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36407961

RESUMEN

Kifunensine is a known inhibitor of type I α-mannosidase enzymes and has been shown to have therapeutic potential for a variety of diseases and application in the expression of high-mannose N-glycan bearing glycoproteins; however, the compound's hydrophilic nature limits its efficacy. We previously synthesized two hydrophobic acylated derivatives of kifunensine, namely, JDW-II-004 and JDW-II-010, and found that these compounds were over 75-fold more potent than kifunensine. Here we explored the effects of these compounds on different mice and human B cells, and we demonstrate that they affected the cells in a similar fashion to kifunensine, further demonstrating their functional equivalence to kifunensine in assays utilizing primary cells. Specifically, a dose-dependent increase in the formation of high-mannose N-glycans decorated glycoproteins were observed upon treatment with kifunensine, JDW-II-004, and JDW-II-010, but greater potency was observed with the acylated derivatives. Treatment with kifunensine or the acylated derivatives also resulted in impaired B-cell receptor (BCR) signaling of the primary mouse B cells; however, primary human B cells treated with kifunensine or JDW-II-004 did not affect BCR signaling, while a modest increase in BCR signaling was observed upon treatment with JDW-010. Nevertheless, these findings demonstrate that the hydrophobic acylated derivatives of kifunensine can help overcome the mass-transfer limitations of the parent compound, and they may have applications for the treatment of ERAD-related diseases or prove to be more cost-effective alternatives for the generation and production of high-mannose N-glycan bearing glycoproteins.

8.
Artículo en Inglés | MEDLINE | ID: mdl-35995551

RESUMEN

BACKGROUND: MR-guided focused ultrasound (MRgFUS) thalamotomy has been shown to be a safe and effective treatment for essential tremor (ET). OBJECTIVE: To investigate the effects of MRgFUS in patients with ET with an emphasis on ipsilateral-hand and axial tremor subscores. METHODS: Tremor scores and adverse effects of 100 patients treated between 2012 and 2018 were assessed at 1 week, 3, 12, and 24 months. A subgroup analysis of ipsilateral-hand tremor responders (defined as patients with ≥30% improvement at any time point) and non-responders was performed. Correlations and predictive factors for improvement were analysed. Weighted probabilistic maps of improvement were generated. RESULTS: Significant improvement in axial, contralateral-hand and total tremor scores was observed at all study visits from baseline (p<0.0001). There was no significant improvement in ipsilateral subscores. A subset of patients (n=20) exhibited group-level ipsilateral-hand improvement that remained significant through all follow-ups (p<0.001). Multivariate regression analysis revealed that higher baseline scores predict better improvement in ipsilateral-hand and axial tremor. Probabilistic maps demonstrated that the lesion hotspot for axial improvement was situated more medially than that for contralateral improvement. CONCLUSION: MRgFUS significantly improved axial, contralateral-hand and total tremor scores. In a subset of patients, a consistent group-level treatment effect was observed for ipsilateral-hand tremor. While ipsilateral improvement seemed to be less directly related to lesion location, a spatial relationship between lesion location and axial and contralateral improvement was observed that proved consistent with the somatotopic organisation of the ventral intermediate nucleus. TRIAL REGISTRATION NUMBERS: NCT01932463, NCT01827904, and NCT02252380.

9.
Chembiochem ; 23(19): e202200266, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-35816406

RESUMEN

Cancer-associated alterations to glycosylation have been shown to aid cancer development and progression. An increased abundance of high mannose N-glycans has been observed in several cancers. Here, we describe the preparation of lectin drug conjugates (LDCs) that permit toxin delivery to cancer cells presenting high mannose N-glycans. Additionally, we demonstrate that cancer cells presenting low levels of high mannose N-glycans can be rendered sensitive to the LDCs by co-treatment with a type I mannosidase inhibitor. Our findings establish that an increased abundance of high mannose N-glycans in the glycocalyx of cancer cells can be leveraged to enable toxin delivery.


Asunto(s)
Lectinas , Manosa , Manosidasas , Preparaciones Farmacéuticas , Polisacáridos
10.
J Neurosurg ; 136(1): 215-220, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34144526

RESUMEN

Dysgeusia, or distorted taste, has recently been acknowledged as a complication of thalamic ablation or thalamic deep brain stimulation as a treatment of tremor. In a unique patient, left-sided MR-guided focused ultrasound thalamotomy improved right-sided essential tremor but also induced severe dysgeusia. Although dysgeusia persisted and caused substantial weight loss, tremor slowly relapsed. Therefore, 19 months after the first procedure, the patient underwent a second focused ultrasound thalamotomy procedure, which again improved tremor but also completely resolved the dysgeusia. On the basis of normative and patient-specific whole-brain tractography, the authors determined the relationship between the thalamotomy lesions and the medial border of the medial lemniscus-a surrogate for the solitariothalamic gustatory fibers-after the first and second focused ultrasound thalamotomy procedures. Both tractography methods suggested partial and complete disruption of the solitariothalamic gustatory fibers after the first and second thalamotomy procedures, respectively. The tractography findings in this unique patient demonstrate that incomplete and complete disruption of a neural pathway can induce and resolve symptoms, respectively, and serve as the rationale for ablative procedures for neurological and psychiatric disorders.


Asunto(s)
Disgeusia/etiología , Ultrasonido Enfocado de Alta Intensidad de Ablación/efectos adversos , Procedimientos Neuroquirúrgicos/efectos adversos , Tálamo/cirugía , Anciano , Imagen de Difusión Tensora , Temblor Esencial/etiología , Temblor Esencial/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/etiología , Gusto , Tálamo/diagnóstico por imagen , Resultado del Tratamiento
11.
Nat Commun ; 12(1): 3043, 2021 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-34031407

RESUMEN

Commonly used for Parkinson's disease (PD), deep brain stimulation (DBS) produces marked clinical benefits when optimized. However, assessing the large number of possible stimulation settings (i.e., programming) requires numerous clinic visits. Here, we examine whether functional magnetic resonance imaging (fMRI) can be used to predict optimal stimulation settings for individual patients. We analyze 3 T fMRI data prospectively acquired as part of an observational trial in 67 PD patients using optimal and non-optimal stimulation settings. Clinically optimal stimulation produces a characteristic fMRI brain response pattern marked by preferential engagement of the motor circuit. Then, we build a machine learning model predicting optimal vs. non-optimal settings using the fMRI patterns of 39 PD patients with a priori clinically optimized DBS (88% accuracy). The model predicts optimal stimulation settings in unseen datasets: a priori clinically optimized and stimulation-naïve PD patients. We propose that fMRI brain responses to DBS stimulation in PD patients could represent an objective biomarker of clinical response. Upon further validation with additional studies, these findings may open the door to functional imaging-assisted DBS programming.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos , Enfermedad de Parkinson/terapia , Anciano , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/terapia
12.
J Med Microbiol ; 70(5)2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33999799

RESUMEN

EV-D68 is an emerging enterovirus infection associated with severe acute respiratory illness (SARI), acute flaccid myelitis (AFM) and acute flaccid paralysis (AFP). While EV-D68 outbreaks and sporadic cases are reported globally, a single case has been reported from India. The present study aims to investigate the molecular epidemiology and clinical characteristics of EV-D68-associated SARI cases from South India. We screened influenza-negative archived throat swab specimens from Influenza-Like Illness (ILI) and SARI cases (n=959; 2016 to 2018 period) for enteroviruses by pan-enterovirus real-time RT-PCR. Thirteen samples positive for enteroviruses were typed by PCR and sequencing based on VPI, VP2 and/or 5'NCR regions. One EV-D68 RNA sample was subjected to next-generation sequencing for whole genome characterisation. Among 13 enterovirus cases, four were ECHO-11, three EV-D68, two CV-A16 and one each EV-71, CV-B1, CV-B2 and CV-A9. All three cases of EV-D68 infection were reported in children below 2 years of age from Kerala state of South India during June and July 2017. The patients developed pneumonia without any neurological complications. Sequencing based on VPI and 5'NCR regions showed that EV-D68 strains belong to the novel subclade B3. The EV-D68 complete genome identified with two unique amino acid substitutions in VP1 (T-246-I) and 3D (K-344-R) regions. This study reiterates the EV-D68 novel subclade B3 circulation in India and indicates the urgent need for structured EV-D68 surveillance in the country to describe the epidemiology.


Asunto(s)
Enterovirus Humano D/genética , Infecciones por Enterovirus/virología , Neumonía Viral/virología , Sustitución de Aminoácidos , Proteínas de la Cápside/genética , Enterovirus Humano D/clasificación , Infecciones por Enterovirus/epidemiología , Femenino , Genoma Viral , Humanos , India/epidemiología , Lactante , Masculino , Epidemiología Molecular , Filogenia , Neumonía Viral/epidemiología , Polimorfismo Genético , Recombinación Genética , Proteínas Virales/química , Proteínas Virales/genética , Secuenciación Completa del Genoma
13.
Cureus ; 13(2): e13174, 2021 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-33717719

RESUMEN

The gene PTRH2 encodes a protein with peptidyl-tRNA hydrolase activity and is involved in the translation process in protein synthesis. The kinesin family member 1-A (KIF1A) gene encodes a molecular motor involved in axonal transport along microtubules. Mutations in these genes lead to respective phenotypical conditions that have been reported in the literature. In this paper, we present a novel syndrome of concurrent occurrence of mutations in the PTRH2 and KIF1A genes in a 19-year-old girl of Dravidian-Tamil descent from the Southern part of India. The girl presented with global developmental delay, intellectual disability, weakness of upper and lower limbs, and diabetes. On workup, she was found to have severe peripheral axonopathy, outer hair cell (OHC) dysfunction, severe bilateral sensorineural hearing loss (SNHL), total pancreatic lipomatosis, exocrine pancreatic insufficiency, cerebellar atrophy, vertebral artery hypoplasia, and scoliosis. The patient had a deceased elder sibling who also had had a similar phenotype. Whole exome sequencing (WES) revealed a novel variant in the PTRH2 gene and a rare variant in the KIF1A gene. The predominant axonal involvement seen in our patient, which was attributable to KIF1A involvement, distinguishes this syndrome from the infantile-onset multisystem neurologic, endocrine, and pancreatic disease (IMNEPD) caused by PTRH2 involvement alone. To the best of our knowledge, this is the first report in the medical literature of a syndrome caused by the synergistic occurrence of mutations in the PTRH2 and KIF1A genes. In order to provide more clarity on the genetic and clinical features of such syndromes and to aid the treating clinician to recognize the existence of such syndromes, we propose the broader umbrella term "neuro-pancreatic syndromes" (NPS). Presently, under NPS, we include two entities: the syndrome described by us in this paper and the IMNEPD. Prompt and effective recognition and management of such NPS would immensely benefit the patient in terms of treatment and prognosis. Furthermore, we hope that this paper will promote further understanding of NPS and foster more research, both clinical and genetic, which would widen the spectrum of NPS. Eventually, this would throw more light on treatment options and ultimately benefit patients with NPS.

14.
Angew Chem Int Ed Engl ; 60(22): 12313-12318, 2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-33728787

RESUMEN

An engineered cyanovirin-N homologue that exhibits specificity for high mannose N-glycans has been constructed to aid type I α 1,2-mannosidase inhibitor discovery and development. Engineering the lectins C-terminus permitted facile functionalization with fluorophores via a sortase and click strategy. The resulting lectin constructs exhibit specificity for cells presenting high mannose N-glycans. Importantly, these lectin constructs can also be applied to specifically assess changes in cell surface glycosylation induced by type I mannosidase inhibitors. Testing the utility of these lectin constructs led to the discovery of type I mannosidase inhibitors with nanomolar potency. Cumulatively, these findings reveal the specificity and utility of the functionalized cyanovirin-N homologue constructs, and highlight their potential in analytical contexts that require high mannose-specific lectins.


Asunto(s)
Lectinas/química , Manosidasas/antagonistas & inhibidores , Alcaloides/química , Alcaloides/metabolismo , Secuencias de Aminoácidos , Aminoaciltransferasas/química , Proteínas Bacterianas/química , Línea Celular , Cisteína Endopeptidasas/química , Diseño de Fármacos , Colorantes Fluorescentes/química , Glicosilación , Humanos , Lectinas/metabolismo , Manosa/química , Manosa/metabolismo , Manosidasas/metabolismo , Microscopía Fluorescente
15.
Ann Neurol ; 89(3): 426-443, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33252146

RESUMEN

Deep brain stimulation (DBS) depends on precise delivery of electrical current to target tissues. However, the specific brain structures responsible for best outcome are still debated. We applied probabilistic stimulation mapping to a retrospective, multidisorder DBS dataset assembled over 15 years at our institution (ntotal = 482 patients; nParkinson disease = 303; ndystonia = 64; ntremor = 39; ntreatment-resistant depression/anorexia nervosa = 76) to identify the neuroanatomical substrates of optimal clinical response. Using high-resolution structural magnetic resonance imaging and activation volume modeling, probabilistic stimulation maps (PSMs) that delineated areas of above-mean and below-mean response for each patient cohort were generated and defined in terms of their relationships with surrounding anatomical structures. Our results show that overlap between PSMs and individual patients' activation volumes can serve as a guide to predict clinical outcomes, but that this is not the sole determinant of response. In the future, individualized models that incorporate advancements in mapping techniques with patient-specific clinical variables will likely contribute to the optimization of DBS target selection and improved outcomes for patients. ANN NEUROL 2021;89:426-443.


Asunto(s)
Anorexia Nerviosa/terapia , Estimulación Encefálica Profunda/métodos , Trastorno Depresivo Resistente al Tratamiento/terapia , Distonía/terapia , Enfermedad de Parkinson/terapia , Temblor/terapia , Adulto , Anciano , Mapeo Encefálico , Conectoma , Femenino , Globo Pálido/diagnóstico por imagen , Giro del Cíngulo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelación Específica para el Paciente , Probabilidad , Estudios Retrospectivos , Núcleo Subtalámico/diagnóstico por imagen , Resultado del Tratamiento , Núcleos Talámicos Ventrales/diagnóstico por imagen
16.
Pain ; 161(12): 2805-2819, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32694384

RESUMEN

Central poststroke pain (CPSP) is a debilitating and often treatment-refractory condition that affects numerous stroke patients. The location of lesions most likely to cause pain and the identity of the functional brain networks that they impinge upon remain incompletely understood. We aimed to (1) elucidate which lesion locations are most frequently accompanied by pain; (2) explore CPSP-associated functional networks; and (3) examine how neuromodulation interacts with these networks. This multisite study investigated 17 CPSP patients who received deep brain stimulation (DBS; n = 12) or motor cortex stimulation (MCS; n = 5). Pain-causing lesions were manually segmented and normalized to standard space. To identify areas linked to high risk of pain, the locations of CPSP lesions and 220 control lesions were compared using voxelwise odds ratio mapping. The functional connectivity of pain-causing lesions was obtained using a large (n = 1000) normative resting-state functional MRI connectome and compared to that of control lesions and therapeutic DBS activation volumes. Brain regions most associated with CPSP risk (highest value = 63 times) were located along the ascending somatosensory pathways. These areas and the majority of individual CPSP lesions were functionally connected to anterior/middle cingulate cortex, insula, thalamus, and inferior parietal lobule (PBonferroni < 0.05). The extent of connectivity to the thalamus, inferior parietal lobule, and precuneus also differed between CPSP and control lesions (PBonferroni < 0.05). Posterior insula and thalamus shared connectivity with both CPSP lesions and pain-alleviating DBS activation volumes (PBonferroni < 0.05). These findings further clarify the topography and functional connectivity of pain-causing brain lesions, and provide new insights into the network-level mechanism of CPSP neuromodulation.


Asunto(s)
Corteza Motora , Accidente Cerebrovascular , Analgésicos , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Tálamo/diagnóstico por imagen
17.
Brain Stimul ; 13(1): 10-14, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31582301

RESUMEN

BACKGROUND: Panic attacks affect a sizeable proportion of the population. The neurocircuitry of panic remains incompletely understood. OBJECTIVE: To investigate the neuroanatomical underpinnings of panic attacks induced by deep brain stimulation (DBS) through (1) connectomic analysis of an obsessive-compulsive disorder patient who experienced panic attacks during inferior thalamic peduncle DBS; (2) appraisal of existing clinical reports on DBS-induced panic attacks. METHODS: Panicogenic, ventral contact stimulation was compared with benign stimulation at other contacts using volume of tissue activated (VTA) modelling. Networks associated with the panicogenic zone were investigated using state-of-the-art normative connectivity mapping. In addition, a literature search for prior reports of DBS-induced panic attacks was conducted. RESULTS: Panicogenic VTAs impinged primarily on the tuberal hypothalamus. Compared to non-panicogenic VTAs, panicogenic loci were significantly functionally coupled to limbic and brainstem structures, including periaqueductal grey and amygdala. Previous studies found stimulation of these areas can also provoke panic attacks. CONCLUSIONS: DBS in the region of the tuberal hypothalamus elicited panic attacks in a single obsessive-compulsive disorder patient and recruited a network of structures previously implicated in panic pathophysiology, reinforcing the importance of the hypothalamus as a hub of panicogenic circuitry.


Asunto(s)
Conectoma/métodos , Estimulación Encefálica Profunda/métodos , Hipotálamo/fisiopatología , Red Nerviosa/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Trastorno Obsesivo Compulsivo/terapia , Adulto , Amígdala del Cerebelo/fisiopatología , Conectoma/psicología , Femenino , Humanos , Trastorno Obsesivo Compulsivo/psicología , Tálamo/fisiopatología
18.
J Neurotrauma ; 36(5): 650-660, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30024343

RESUMEN

Mild traumatic brain injury (mTBI) affects about 42 million people worldwide. It is often associated with headache, cognitive deficits, and balance difficulties but rarely shows any abnormalities on conventional computed tomography (CT) or magnetic resonance imaging (MRI). Although in most mTBI patients the symptoms resolve within 3 months, 10-15% of patients continue to exhibit symptoms beyond a year. Also, it is known that there exists a vulnerable period post-injury, when a second injury may exacerbate clinical prognosis. Identifying this vulnerable period may be critical for patient outcome, but very little is known about the neural underpinnings of mTBI and its recovery. In this work, we used advanced functional neuroimaging to study longitudinal changes in functional organization of the brain during the 3-month recovery period post-mTBI. Fractional amplitude of low frequency fluctuations (fALFF) measured from resting state functional MRI (rs-fMRI) was found to be associated with symptom severity score (SSS, r = -0.28, p = 0.002). Decreased fALFF was observed in specific functional networks for patients with higher SSS, and fALFF returned to higher values when the patient recovered (lower SSS). In addition, functional connectivity of the same networks was found to be associated with concurrent SSS, and connectivity immediately after injury (<10 days) was capable of predicting SSS at a later time-point (3 weeks to 3 months, p < 0.05). Specific networks including motor, default-mode, and visual networks were found to be associated with SSS (p < 0.001), and connectivity between these networks predicted 3-month clinical outcome (motor and visual: p < 0.001, default-mode: p < 0.006). Our results suggest that functional connectivity in these networks comprise potential biomarkers for predicting mTBI recovery profiles and clinical outcome.


Asunto(s)
Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Síndrome Posconmocional/diagnóstico por imagen , Síndrome Posconmocional/fisiopatología , Recuperación de la Función/fisiología , Adolescente , Adulto , Conmoción Encefálica/diagnóstico por imagen , Conmoción Encefálica/fisiopatología , Femenino , Neuroimagen Funcional , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Descanso , Adulto Joven
19.
Magn Reson Imaging ; 53: 1-6, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29928936

RESUMEN

BACKGROUND AND OBJECTIVES: Ensuring patient comfort and compliance by emphasizing reduced time frame for image acquisition, without compromising image quality is the key aspect with functional MRI examination. Multiband resting state fMRI (MB-rsfMRI) is a fairly new technique that potentially shortens MR image acquisition time by providing increased number of time points. The study aims to compare signal characteristics as well as the functional connectivity using conventional resting-state fMRI (rsfMRI) with that of MB-rsfMRI technique. MATERIALS AND METHODS: 9 healthy volunteers have prospectively undergone conventional resting-state fMRI and Multiband rsfMRI scanning technique in a 3T GE scanner (Discovery MR750w™). We compared the temporal SNR (tSNR) of conventional rs-fMRI with that of MB-rsfMRI. We looked at the language network connectivity and small world network characteristics from graph theoretical measures to compare the two techniques. RESULTS: We computed the tSNR of conventional resting-state fMRI (rsfMRI) and MB-rsfMRI technique. A strong positive correlation was seen between graph theoretical measures from MB-rsfMRI and conventional rsfMRI (Pearson Correlation, r = 0.99). Both techniques showed similar small world network characteristics in healthy controls. CONCLUSION: The present study demonstrates negligible differences between the conventional-rsfMRI and MB-rsfMRI acquisitions on the computed graph theoretic measures. Accordingly current analysis proves that MB-rs-fMRI may be used as a time reducing acquisition technique that enables mapping of functional connectivity with similar outcome as conventional rs-fMRI in healthy subjects.


Asunto(s)
Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Encéfalo , Voluntarios Sanos , Humanos , Descanso , Relación Señal-Ruido
20.
Chemistry ; 24(42): 10721-10731, 2018 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-29797369

RESUMEN

A series of intramolecularly hydrogen-bonded zwitterionic compartmental ligands HL1-HL4, containing a pendent diamine arm that is monoprotonated and an aldehyde functionality at two different ortho-positions of a 4-halophenoxide, is reported herein. Single-crystal X-ray diffraction (SXRD) provides persuasive evidence for the identification of this class of proton-transferred zwitterions at room temperature. The solid-state photoluminescent nature of these zwitterions remains intact in aqueous and organic solutions. Grinding of HL1 and HL2 with Cu2+ /Ni2+ salts develop turn-on probes 1-4. Compounds 1 and 4 are dinuclear CuII and NiII species, respectively. Compound 2 is a tetranuclear CuII complex. Interestingly, compound 3 is a mononuclear NiII species in which both nitrogen atoms in the pendant diamine arm are protonated and, therefore, not coordinated to the NiII center. All these probes (1-4) display an instant response to the poison gas hydrogen cyanide (HCN) and cyanide salts present in both solid matrices and aqueous (100 % water) solution. Selective and rapid sensing of HCN gas and cyanide salts in solid/soil/water phases, without any interference, by the mechanosynthesized complexes 1-4 can be perceived easily by the naked eye under a hand-held UV lamp.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...