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1.
J Physiol ; 602(12): 2931-2943, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38872383

RESUMEN

Theta-burst transcranial ultrasound stimulation (tbTUS) increases primary motor cortex (M1) excitability for at least 30 min. However, the remote effects of focal M1 tbTUS on the excitability of other cortical areas are unknown. Here, we examined the effects of left M1 tbTUS on right M1 excitability. An 80 s train of active or sham tbTUS was delivered to the left M1 in 20 healthy subjects. Before and after the tbTUS, we measured: (1) corticospinal excitability using motor-evoked potential (MEP) amplitudes from single-pulse transcranial magnetic stimulation (TMS) of left and right M1; (2) interhemispheric inhibition (IHI) from left to right M1 and from right to left M1 using a dual-site paired-pulse TMS paradigm; and (3) intracortical circuits of the right M1 with short-interval intracortical inhibition and intracortical facilitation (ICF) using paired-pulse TMS. Left M1 tbTUS decreased right M1 excitability as shown by decreased MEP amplitudes, increased right M1 ICF and decreased short-interval IHI from left to right hemisphere at interstimulus interval (ISI) of 10 ms but not long-interval IHI at interstimulus interval of 40 ms. The study showed that left M1 tbTUS can change the excitability of remote cortical areas with decreased right M1 excitability and interhemispheric inhibition. The remote effects of tbTUS should be considered when it is used in neuroscience research and as a potential neuromodulation treatment for brain disorders. KEY POINTS: Transcranial ultrasound stimulation (TUS) is a novel non-invasive brain stimulation technique for neuromodulation with the advantages of being able to achieve high spatial resolution and target deep brain structures. A repetitive TUS protocol, with an 80 s train of theta burst patterned TUS (tbTUS), has been shown to increase primary motor cortex (M1) excitability, as well as increase alpha and beta movement-related spectral power in distinct brain regions. In this study, we examined on the effects of the motor cortical tbTUS on the excitability of contralateral M1 measured with MEPs elicited by transcranial magnetic stimulation. We showed that left M1 tbTUS decreased right M1 excitability and left-to-right M1 interhemispheric inhibition, and increased intracortical facilitation of right M1. These results lead to better understand the effects of tbTUS and can help the development of tbTUS for the treatment of neurological and psychiatric disorders and in neuroscience research.


Asunto(s)
Potenciales Evocados Motores , Corteza Motora , Estimulación Magnética Transcraneal , Humanos , Corteza Motora/fisiología , Masculino , Femenino , Adulto , Estimulación Magnética Transcraneal/métodos , Adulto Joven , Ritmo Teta
2.
Neurobiol Dis ; 199: 106557, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38852752

RESUMEN

BACKGROUND: Freezing of gait (FOG) is a debilitating symptom of Parkinson's disease (PD) characterized by paroxysmal episodes in which patients are unable to step forward. A research priority is identifying cortical changes before freezing in PD-FOG. METHODS: We tested 19 patients with PD who had been assessed for FOG (n=14 with FOG and 5 without FOG). While seated, patients stepped bilaterally on pedals to progress forward through a virtual hallway while 64-channel EEG was recorded. We assessed cortical activities before and during lower limb motor blocks (LLMB), defined as a break in rhythmic pedaling, and stops, defined as movement cessation following an auditory stop cue. This task was selected because LLMB correlates with FOG severity in PD and allows recording of high-quality EEG. Patients were tested after overnight withdrawal from dopaminergic medications ("off" state) and in the "on" medications state. EEG source activities were evaluated using individual MRI and standardized low resolution brain electromagnetic tomography (sLORETA). Functional connectivity was evaluated by phase lag index between seeds and pre-defined cortical regions of interest. RESULTS: EEG source activities for LLMB vs. cued stops localized to right posterior parietal area (Brodmann area 39), lateral premotor area (Brodmann area 6), and inferior frontal gyrus (Brodmann area 47). In these areas, PD-FOG (n=14) increased alpha rhythms (8-12 Hz) before LLMB vs. typical stepping, whereas PD without FOG (n=5) decreased alpha power. Alpha rhythms were linearly correlated with LLMB severity, and the relationship became an inverted U-shape when assessing alpha rhythms as a function of percent time in LLMB in the "off" medication state. Right inferior frontal gyrus and supplementary motor area connectivity was observed before LLMB in the beta band (13-30 Hz). This same pattern of connectivity was seen before stops. Dopaminergic medication improved FOG and led to less alpha synchronization and increased functional connections between frontal and parietal areas. CONCLUSIONS: Right inferior parietofrontal structures are implicated in PD-FOG. The predominant changes were in the alpha rhythm, which increased before LLMB and with LLMB severity. Similar connectivity was observed for LLMB and stops between the right inferior frontal gyrus and supplementary motor area, suggesting that FOG may be a form of "unintended stopping." These findings may inform approaches to neurorehabilitation of PD-FOG.

3.
J Evol Biol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38766701

RESUMEN

Intraspecific variation in vertebrate eye size is well known. Ecological factors such as light availability are often correlated with shifts in relative eye size. However, experimental tests of selection on eye size are lacking. Trinidadian killifish (Anablepsoides hartii) are found in sites that differ in predation intensity. Sites that lack predators are characterized by lower light, high killifish densities, low resource availability, and intense competition for food. We previously found that killifish in sites that lack predators have evolved a larger 'relative' eye size (eye size corrected for body size) than fish from sites with predators. Here we used transplant experiments to test how selection operates on eye size when fish that are adapted to sites with predators are translocated into sites where predators are absent. We observed a significant 'population × relative eye size' interaction; the relationship between relative eye size and a proxy for fitness (rates of individual growth) was positive in the transplanted fish. The trend was opposite for resident fish. Such results provide experimental support that larger eyes enhance fitness and are favoured in environments characterized by low light and high competition.

4.
Mol Cell Proteomics ; 23(5): 100767, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615877

RESUMEN

DNA replication is a fundamental cellular process that ensures the transfer of genetic information during cell division. Genome duplication takes place in S phase and requires a dynamic and highly coordinated recruitment of multiple proteins at replication forks. Various genotoxic stressors lead to fork instability and collapse, hence the need for DNA repair pathways. By identifying the multitude of protein interactions implicated in those events, we can better grasp the complex and dynamic molecular mechanisms that facilitate DNA replication and repair. Proximity-dependent biotin identification was used to identify associations with 17 proteins within four core replication components, namely the CDC45/MCM2-7/GINS helicase that unwinds DNA, the DNA polymerases, replication protein A subunits, and histone chaperones needed to disassemble and reassemble chromatin. We further investigated the impact of genotoxic stress on these interactions. This analysis revealed a vast proximity association network with 108 nuclear proteins further modulated in the presence of hydroxyurea; 45 being enriched and 63 depleted. Interestingly, hydroxyurea treatment also caused a redistribution of associations with 11 interactors, meaning that the replisome is dynamically reorganized when stressed. The analysis identified several poorly characterized proteins, thereby uncovering new putative players in the cellular response to DNA replication arrest. It also provides a new comprehensive proteomic framework to understand how cells respond to obstacles during DNA replication.


Asunto(s)
Replicación del ADN , Hidroxiurea , Proteómica , Hidroxiurea/farmacología , Proteómica/métodos , Humanos , Daño del ADN , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteoma/metabolismo
5.
Cureus ; 16(3): e56408, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38638790

RESUMEN

Introduction Residual neuromuscular block, defined as a quantitatively measured train-of-four ratio (TOFr) <0.9, is common postoperatively. Using a pragmatic trial design, we hypothesized that qualitative and/or clinical assessment of neuromuscular block would inadequately detect residual block following antagonism with neostigmine or sugammadex. Method After IRB approval and written informed consent, 74 children (aged 2-17 years), undergoing elective surgery and receiving rocuronium, were prospectively enrolled in the study at Children's Hospital Colorado and Children's Healthcare of Atlanta. Routine clinical practice at both institutions consisted of clinical signs and/or qualitative assessment with peripheral nerve stimulators. Children at the Colorado hospital routinely received sugammadex antagonism; whereas children at the Atlanta hospital received neostigmine. Residual neuromuscular block was assessed postoperatively using quantitative electromyography. If TOFr was <0.9, patients received sugammadex until TOFr ≥0.9. Result Qualitative and clinical assessment failed to detect residual block in 29.7% of patients in the neostigmine reversal cohort (adjusted odds ratio (aOR) 29.8, 95% confidence interval (CI): 2.7 to 5,559.5, p-value = 0.002). No residual block was detected in the sugammadex reversal cohort. A correlation between increasing patient weight and incidence of postoperative residual block was observed in the neostigmine cohort (aOR 1.05, 95% CI: 1.02 to 1.10, p-value = 0.002). Conclusion Qualitative and/or clinical assessment of neuromuscular block inadequately detects residual block following neostigmine antagonism.

6.
Mol Neurobiol ; 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240991

RESUMEN

The pleomorphic adenoma gene 1 (Plag1) is a transcription factor involved in the regulation of growth and cellular proliferation. Here, we report the spatial distribution and functional implications of PLAG1 expression in the adult mouse brain. We identified Plag1 promoter-dependent ß-galactosidase expression in various brain structures, including the hippocampus, cortex, choroid plexus, subcommisural organ, ependymal cells lining the third ventricle, medial and lateral habenulae and amygdala. We noted striking spatial-restriction of PLAG1 within the cornu ammonis (CA1) region of the hippocampus and layer-specific cortical expression, with abundant expression noted in all layers except layer 5. Furthermore, our study delved into the role of PLAG1 in neurodevelopment, focusing on its impact on neural stem/progenitor cell proliferation. Loss of Plag1 resulted in reduced proliferation and decreased production of neocortical progenitors in vivo, although ex vivo neurosphere experiments revealed no cell-intrinsic defects in the proliferative or neurogenic capacity of Plag1-deficient neural progenitors. Lastly, we explored potential target genes of PLAG1 in the cortex, identifying that Neurogenin 2 (Ngn2) was significantly downregulated in Plag1-deficient mice. In summary, our study provides novel insights into the spatial distribution of PLAG1 expression in the adult mouse brain and its potential role in neurodevelopment. These findings expand our understanding of the functional significance of PLAG1 within the brain, with potential implications for neurodevelopmental disorders and therapeutic interventions.

7.
Trends Ecol Evol ; 39(3): 225-228, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38267287

RESUMEN

Positive frequency-dependent selection should theoretically lead to monomorphic warning coloration. Instead, numerous examples of polymorphic warning signals exist. Biases - for example, in human perception - hinder our appreciation and research of understanding warning signal diversity. We propose strategies to counter such biases and objectively move our field forward.

8.
Neurobiol Dis ; 190: 106384, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38135193

RESUMEN

External sensory cues can reduce freezing of gait in people with Parkinson's disease (PD), yet the role of the basal ganglia in these movements is unclear. We used microelectrode recordings to examine modulations in single unit (SU) and oscillatory local field potentials (LFP) during auditory-cued rhythmic pedaling movements of the feet. We tested five blocks of increasing cue frequencies (1 Hz, 1.5 Hz, 2 Hz, 2.5 Hz, and 3 Hz) in 24 people with PD undergoing deep brain stimulation surgery of the subthalamic nucleus (STN) or globus pallidus internus (GPi). Single unit firing and beta band LFPs (13-30 Hz) in response to movement onsets or cue onsets were examined. We found that the timing accuracy of foot pedaling decreased with faster cue frequencies. Increasing cue frequencies also attenuated firing rates in both STN and GPi neurons. Peak beta power in the GPi and STN showed different responses to the task. GPi beta power showed persistent suppression with fast cues and phasic modulation with slow cues. STN beta power showed enhanced beta synchronization following movement. STN beta power also correlated with rate of pedaling. Overall, we showed task-related responses in the GPi and STN during auditory-cued movements with differential roles in sensory and motor control. The results suggest a role for both input and output basal ganglia nuclei in auditory rhythmic pacing of gait-like movements in PD.


Asunto(s)
Estimulación Encefálica Profunda , Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Núcleo Subtalámico , Humanos , Enfermedad de Parkinson/terapia , Globo Pálido/fisiología , Señales (Psicología) , Núcleo Subtalámico/fisiología , Neuronas/fisiología , Estimulación Encefálica Profunda/métodos
9.
Parkinsonism Relat Disord ; 116: 105886, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37866253

RESUMEN

Postural control requires effective sensory integration. People with Parkinson's disease (PD) are reported to have impaired visual and vestibular perception. While self-motion perception is a key aspect of locomotion, visual-vestibular integration has not been directly characterized in people with PD during gait. We compared the ability of people with PD and healthy older adults (OA) to integrate multi-sensory information during straight-line walking in response to visual and vestibular perturbations, using continuous translations of the visual surround and galvanic vestibular stimulation within a virtual reality environment. We measured their endpoint deviations from midline and changes in gait parameters. We found that people with PD deviated more than OA when walking in a dark environment but did not show differences in deviations when walking in a virtual room with visual information. With visual and vestibular perturbations, people with PD did not differ from OA in endpoint deviations nor variabilities. However, people with PD did not adopt a more cautious gait when GVS was applied in a virtual room, unlike OA. Overall, we showed that people with mild PD did not perform worse than OA but did show differences in gait patterns, suggesting that visual-vestibular integration is relatively preserved during gait in PD.


Asunto(s)
Enfermedad de Parkinson , Humanos , Anciano , Enfermedad de Parkinson/complicaciones , Caminata/fisiología , Marcha/fisiología , Locomoción , Equilibrio Postural/fisiología
10.
Cell ; 186(22): 4898-4919.e25, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37827155

RESUMEN

Expansions of repeat DNA tracts cause >70 diseases, and ongoing expansions in brains exacerbate disease. During expansion mutations, single-stranded DNAs (ssDNAs) form slipped-DNAs. We find the ssDNA-binding complexes canonical replication protein A (RPA1, RPA2, and RPA3) and Alternative-RPA (RPA1, RPA3, and primate-specific RPA4) are upregulated in Huntington disease and spinocerebellar ataxia type 1 (SCA1) patient brains. Protein interactomes of RPA and Alt-RPA reveal unique and shared partners, including modifiers of CAG instability and disease presentation. RPA enhances in vitro melting, FAN1 excision, and repair of slipped-CAGs and protects against CAG expansions in human cells. RPA overexpression in SCA1 mouse brains ablates expansions, coincident with decreased ATXN1 aggregation, reduced brain DNA damage, improved neuron morphology, and rescued motor phenotypes. In contrast, Alt-RPA inhibits melting, FAN1 excision, and repair of slipped-CAGs and promotes CAG expansions. These findings suggest a functional interplay between the two RPAs where Alt-RPA may antagonistically offset RPA's suppression of disease-associated repeat expansions, which may extend to other DNA processes.


Asunto(s)
Proteína de Replicación A , Expansión de Repetición de Trinucleótido , Animales , Humanos , Ratones , ADN/genética , Reparación de la Incompatibilidad de ADN , Enfermedad de Huntington/genética , Proteínas/genética , Ataxias Espinocerebelosas/genética , Proteína de Replicación A/metabolismo
11.
J Med Virol ; 95(8): e29029, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37565686

RESUMEN

The impact and frequency of infectious disease outbreaks demonstrate the need for timely genomic surveillance to inform public health responses. In the largest known outbreak of mpox, genomic surveillance efforts have primarily focused on high-incidence nations in Europe and the Americas, with a paucity of data from South-East Asia and the Western Pacific. Here we analyzed 102 monkeypox virus (MPXV) genomes sampled from 56 individuals in Melbourne, Australia. All genomes fell within the 2022 MPXV outbreak lineage (B.1), with likely onward local transmission detected. We observed within-host diversity and instances of co-infection, and highlight further examples of structural variation and apolipoprotein B editing complex-driven micro-evolution in the current MPXV outbreak. Updating our understanding of MPXV emergence and diversification will inform public health measures and enable monitoring of the virus' evolutionary trajectory throughout the mpox outbreak.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Mpox/epidemiología , Genómica , Brotes de Enfermedades , Australia/epidemiología
13.
Vaccine ; 40(50): 7321-7327, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-36344361

RESUMEN

The current worldwide monkepox outbreak has reaffirmed the continued threat monkeypox virus (MPXV) poses to public health. JYNNEOS, a Modified Vaccinia Ankara (MVA)-based live, non-replicating vaccine, was recently approved for monkeypox prevention for adults at high risk of MPXV infection in the United States. Although the safety and immunogenicity of JYNNEOS have been examined previously, the clinical cohorts studied largely derive from regions where MPXV does not typically circulate. In this study, we assess the quality and longevity of serological responses to two doses of JYNNEOS vaccine in a large cohort of healthcare workers from the Democratic Republic of Congo (DRC). We show that JYNNEOS elicits a strong orthopoxvirus (OPXV)-specific antibody response in participants that peaks around day 42, or 2 weeks after the second vaccine dose. Participants with no prior history of smallpox vaccination or exposure have lower baseline antibody levels, but experience a similar fold-rise in antibody titers by day 42 as those with a prior history of vaccination. Both previously naïve and vaccinated participants generate vaccinia virus and MPXV-neutralizing antibody in response to JYNNEOS vaccination. Finally, even though total OPXV-specific IgG titers and neutralizing antibody titers declined from their peak and returned close to baseline levels by the 2-year mark, most participants remain IgG seropositive at the 2-year timepoint. Taken together, our data demonstrates that JYNNEOS vaccination triggers potent OPXV neutralizing antibody responses in a cohort of healthcare workers in DRC, a monkeypox-endemic region. MPXV vaccination with JYNNEOS may help ameliorate the disease and economic burden associated with monkeypox and combat potential outbreaks in areas with active virus circulation.


Asunto(s)
Mpox , Orthopoxvirus , Vacuna contra Viruela , Vaccinia , Humanos , Adulto , Virus Vaccinia , Mpox/epidemiología , Mpox/prevención & control , República Democrática del Congo/epidemiología , Monkeypox virus , Anticuerpos Neutralizantes , Inmunoglobulina G
14.
Eye Contact Lens ; 48(11): 466-470, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36083177

RESUMEN

OBJECTIVES: To assess scleral lens fluid reservoir (FR) change simultaneously in four quadrants with single acquisition using novel ANTERION anterior segment swept-source optical coherence tomography (SS-OCT). METHODS: A prospective, observational, clinical study of 18 subjects (30 eyes) was performed on adults fitted with a scleral lens for ocular surface disease (n=8), irregular cornea/scar (n=7), and corneal ectasia (n=15). ANTERION anterior segment SS-OCT imaging was obtained at the initial visit and at the follow-up to determine pre and post scleral lens settling, measured in microns, centrally and peripherally. Peripheral measurements were grouped into four quadrants. Repeated-measures ANOVA was performed comparing vault post minus pre differences by quadrant, and TTests comparing difference in FR by lens design were performed with a significant threshold at P <0.05. RESULTS: The mean central scleral lens settling was significant at -48.3±41.7 µm. The change in FR by quadrant was superior (S): -47.8±67.3 µm, inferior (I): -68.0±102.2 µm, nasal (N) -46.3±63.4 µm, and temporal (T): -56.7±49.3 µm. There were no significant differences in lens settling between the quadrants. Within the three categories, the irregular cornea group experienced significantly greater lens settling. There was no significant difference in central FR when comparing lens design or lens diameter. CONCLUSIONS: The ANTERION SS-OCT allows for high-resolution central and peripheral assessment of FR in scleral lens wear. With increased technology available for scleral lens customization, this imaging modality can assist in more detailed assessment in quadrant-specific scleral lens designs.


Asunto(s)
Lentes de Contacto , Tomografía de Coherencia Óptica , Adulto , Humanos , Tomografía de Coherencia Óptica/métodos , Estudios Prospectivos , Esclerótica/diagnóstico por imagen , Córnea/diagnóstico por imagen
15.
JCI Insight ; 7(10)2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35603789

RESUMEN

The eukaryotic CDC45/MCM2-7/GINS (CMG) helicase unwinds the DNA double helix during DNA replication. The GINS subcomplex is required for helicase activity and is, therefore, essential for DNA replication and cell viability. Here, we report the identification of 7 individuals from 5 unrelated families presenting with a Meier-Gorlin syndrome-like (MGS-like) phenotype associated with hypomorphic variants of GINS3, a gene not previously associated with this syndrome. We found that MGS-associated GINS3 variants affecting aspartic acid 24 (D24) compromised cell proliferation and caused accumulation of cells in S phase. These variants shortened the protein half-life, altered key protein interactions at the replisome, and negatively influenced DNA replication fork progression. Yeast expressing MGS-associated variants of PSF3 (the yeast GINS3 ortholog) also displayed impaired growth, S phase progression defects, and decreased Psf3 protein stability. We further showed that mouse embryos homozygous for a D24 variant presented intrauterine growth retardation and did not survive to birth, and that fibroblasts derived from these embryos displayed accelerated cellular senescence. Taken together, our findings implicate GINS3 in the pathogenesis of MGS and support the notion that hypomorphic variants identified in this gene impaired cell and organismal growth by compromising DNA replication.


Asunto(s)
Micrognatismo , Saccharomyces cerevisiae , Animales , Proteínas Cromosómicas no Histona , Microtia Congénita , Replicación del ADN/genética , Trastornos del Crecimiento , Humanos , Ratones , Micrognatismo/genética , Proteínas de Mantenimiento de Minicromosoma/genética , Rótula/anomalías
16.
Parkinsonism Relat Disord ; 96: 6-12, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35093853

RESUMEN

BACKGROUND: Deep brain stimulation of the subthalamic nucleus is effective to alleviate motor symptoms in advanced Parkinson's disease. Using a novel conditioning paradigm, it has been shown that deep brain stimulation pulses from electrodes in the subthalamic nucleus modulate corticospinal excitability as determined with transcranial magnetic stimulation applied to the motor cortex. The mechanism of action is unclear. OBJECTIVE: To investigate the effects of subthalamic nucleus and dorsal premotor cortex conditioning on corticospinal excitability as a function of interstimulus intervals between target areas and deep brain stimulation frequencies. METHODS: In 19 patients with Parkinson's disease with subthalamic nucleus deep brain stimulation, the premotor-motor interaction was investigated in four different deep brain stimulation conditions (off, clinically used settings, 3 Hz, 20 Hz). Transcranial magnetic pulses were applied to the premotor and motor cortex and paired at certain intervals with deep brain stimulation pulses. The volume of tissue activated by deep brain stimulation was correlated with neurophysiological findings. RESULTS: There was distinct motor cortex inhibition by premotor cortex conditioning at an interstimulus interval of 1 ms before the motor cortex stimulation. Subthalamic nucleus conditioning with deep brain stimulation frequencies of 3 and 20 Hz at an interstimulus interval of 10 ms between subthalamic nucleus and primary motor cortex reduced premotor-motor inhibition. The volume of tissue activated by deep brain stimulation correlated positively with this effect. Corticospinal excitability was not affected by subthalamic nucleus conditioning as used here. CONCLUSIONS: Premotor-motor inhibition is modulated by subthalamic nucleus conditioning, presumably through the monosynaptic hyperdirect pathway.


Asunto(s)
Estimulación Encefálica Profunda , Corteza Motora , Enfermedad de Parkinson , Núcleo Subtalámico , Humanos , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiología , Estimulación Magnética Transcraneal
17.
Hepatology ; 75(4): 968-982, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34662439

RESUMEN

BACKGROUND AND AIMS: Lipoprotein Z (LP-Z) is an abnormal free cholesterol (FC)-enriched LDL-like particle discovered from patients with cholestatic liver disease. This study aims to define the diagnostic value of LP-Z in alcohol-associated hepatitis (AH) and interrogate the biology behind its formation. APPROACH AND RESULTS: We measured serum levels of LP-Z using nuclear magnetic resonance spectroscopy, a well-established clinical assay. Serum levels of LP-Z were significantly elevated in four AH cohorts compared with control groups, including heavy drinkers and patients with cirrhosis. We defined a Z-index, calculated by the ratio of LP-Z to total apolipoprotein B-containing lipoproteins, representing the degree of deviation from normal VLDL metabolism. A high Z-index was associated with 90-day mortality independent from the Model for End-Stage Liver Disease (MELD) and provided added prognosticative value. Both a Z-index ≤ 0.6 and a decline of Z-index by ≥0.1 in 2 weeks predicted 90-day survival. RNA-sequencing analyses of liver tissues demonstrated an inverse association in the expression of enzymes responsible for the extrahepatic conversion of VLDL to LDL and AH disease severity, which was further confirmed by the measurement of serum enzyme activity. To evaluate whether the FC in LP-Z could contribute to the pathogenesis of AH, we found significantly altered FC levels in liver explant of patients with AH. Furthermore, FC in reconstituted LP-Z particles caused direct toxicity to human hepatocytes in a concentration-dependent manner, supporting a pathogenic role of FC in LP-Z. CONCLUSIONS: Impaired lipoprotein metabolism in AH leads to the accumulation of LP-Z in the circulation, which is hepatotoxic from excessive FC. A Z-index ≤ 0.6 predicts 90-day survival independent from conventional biomarkers for disease prognostication.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Hepatitis Alcohólica , Apolipoproteínas B , Colesterol , Humanos , Lipoproteína(a) , Lipoproteínas , Índice de Severidad de la Enfermedad
18.
Support Care Cancer ; 30(3): 2245-2252, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34714415

RESUMEN

PURPOSE: This study aimed to measure the prevalence of menopausal symptoms in patients attending a multidisciplinary model of care clinic at their initial clinic visit and their subsequent follow-up consultation using a validated patient-reported outcome measure to assess whether menopausal symptoms after cancer had improved. METHODS: A retrospective review was conducted of patients attending the clinic in a 12-month period in 2017 (n = 189). Recorded variables included patient demographics, details of index cancer, previous treatments, and menopausal symptom management strategies. Severity of menopausal symptoms was evaluated using the Greene Climacteric Scale. The extent to which patients were bothered by symptoms was combined into two categories and dichotomized (present/absent). Differences in symptom prevalence between the initial consultation and first follow-up visit were examined using McNemar's test. RESULTS: The majority of patients attending the clinic had a history of breast cancer (72%). Fifty-five percent of patients were prescribed a non-hormonal therapy at their initial visit, most commonly gabapentin. Significantly fewer patients reported being bothered by hot flushes, fatigue, sleep difficulties, and loss of interest in sex, anxiety, or troubles concentrating at the first follow-up visit compared to their initial consultation (p < 0.01). CONCLUSION: In this study, there was an improvement in self-reported menopausal symptoms in a significant proportion of cancer survivors attending a multidisciplinary menopause clinic between their initial and first subsequent follow-up consultations.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Femenino , Sofocos/epidemiología , Sofocos/etiología , Humanos , Menopausia , Estudios Retrospectivos
19.
Ann Neurol ; 91(2): 238-252, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34964172

RESUMEN

OBJECTIVE: Transcranial ultrasound stimulation (TUS) is a promising noninvasive brain stimulation technique with advantages of high spatial precision and ability to target deep brain regions. This study aimed to develop a TUS protocol to effectively induce brain plasticity in human subjects. METHODS: An 80-second train of theta burst patterned TUS (tbTUS), regularly patterned TUS (rTUS) with the same sonication duration, and sham tbTUS was delivered to the motor cortex in healthy subjects. Transcranial magnetic stimulation (TMS) was used to examine changes in corticospinal excitability, intracortical inhibition and facilitation, and the site of plasticity induction. The effects of motor cortical tbTUS on a visuomotor task and the effects of occipital cortex tbTUS on motor cortical excitability were also tested. RESULTS: The tbTUS produced consistent increase in corticospinal excitability for at least 30 minutes, whereas rTUS and sham tbTUS produced no significant change. tbTUS decreased short-interval intracortical inhibition and increased intracortical facilitation. The effects of TMS in different current directions suggested that the site of the plastic changes was within the motor cortex. tbTUS to the occipital cortex did not change motor cortical excitability. Motor cortical tbTUS shortened movement time in a visuomotor task. INTERPRETATION: tbTUS is a novel and efficient paradigm to induce cortical plasticity in humans. It has the potential to be developed for neuromodulation treatment for neurological and psychiatric disorders, and to advance neuroscience research. ANN NEUROL 2022;91:238-252.


Asunto(s)
Corteza Motora/efectos de la radiación , Plasticidad Neuronal/efectos de la radiación , Ritmo Teta , Ultrasonido , Adulto , Mapeo Encefálico , Excitabilidad Cortical , Potenciales Evocados Motores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inhibición Neural , Lóbulo Occipital/fisiología , Desempeño Psicomotor/efectos de la radiación , Tractos Piramidales/efectos de la radiación , Estimulación Magnética Transcraneal , Adulto Joven
20.
Am J Manag Care ; 27(11): e395-e399, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34784148

RESUMEN

OBJECTIVES: To assess the effectiveness of a proactive provider intervention in prompting prior authorization (PA) submissions or provider response prior to PA expiration for medically complex Medicaid patients. STUDY DESIGN: Pre-post outreach study with data from pharmacy claims and provider outreach. METHODS: The intervention and historical comparison (control) groups included expired PAs from December 2019 to February 2020 and from December 2018 to February 2019, respectively. Provider outreach, including telephonic and fax attempts, was conducted over a 2-week period prior to PA expiration. Outcomes were classified as positive or negative based on provider conversation coupled with the result (eg, PA submission) for the intervention group and based solely on pharmacy claims for the control group. The primary end point was the percentage of positive outcomes between the groups, analyzed via χ2 test. The time from PA expiration to the new PA submission was evaluated via t test. RESULTS: A total of 342 outreach attempts were conducted for 270 PAs representing 193 unique patients. Outreach was more likely to result in positive outcomes in the intervention group vs no outreach in the control group (87% vs 25%; P < .00001). On average, PAs were submitted 3.5 days prior to expiration in the intervention group vs 13.0 days after expiration in the control group (t = -7.50; P < .00001). CONCLUSIONS: Proactive outreach resulted in a greater percentage of PA submissions and a significantly reduced time to PA submission. These findings provide important information for payers in guiding clinical programs to enhance continuity of care among at-risk populations.


Asunto(s)
Servicios Farmacéuticos , Farmacias , Humanos , Medicaid , Autorización Previa , Estudios Retrospectivos , Estados Unidos
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