Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 523
Filter
1.
Microsc Microanal ; 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39298134

ABSTRACT

We describe the development, operation, and application of the 4D Camera-a 576 by 576 pixel active pixel sensor for scanning/transmission electron microscopy which operates at 87,000 Hz. The detector generates data at ∼480 Gbit/s which is captured by dedicated receiver computers with a parallelized software infrastructure that has been implemented to process the resulting 10-700 Gigabyte-sized raw datasets. The back illuminated detector provides the ability to detect single electron events at accelerating voltages from 30 to 300 kV. Through electron counting, the resulting sparse data sets are reduced in size by 10--300× compared to the raw data, and open-source sparsity-based processing algorithms offer rapid data analysis. The high frame rate allows for large and complex scanning diffraction experiments to be accomplished with typical scanning transmission electron microscopy scanning parameters.

2.
Mult Scler Relat Disord ; 91: 105882, 2024 Sep 07.
Article in English | MEDLINE | ID: mdl-39276598

ABSTRACT

BACKGROUND: Vascular risk factors seem to contribute to disease progression in Multiple Sclerosis (MS), but the mechanistic connection between vascular risk and MS is unknown. Understanding cerebrovascular hemodynamics (CVH) in MS may help advance our understanding of the link between vascular risk and MS. OBJECTIVES: Examine the relationship between CVH [dynamic cerebral autoregulation (dCA) and vasoreactivity (VR)] and brain structure (MRI) and function (cognition, and gait) in individuals with MS. METHODS: Transcranial Doppler ultrasound (TCD) was utilized to assess two key markers of CVH: dCA and VR. dCA (reported as phase and gain) is calculated from the spontaneous blood pressure and flow velocity oscillations. VR is calculated as the slope of change in cerebral blood flow velocity in response to end-tidal CO2. Global gray matter (GM), white matter (WM), WM hyperintensity (WMH) volumes and WM lesion counts were measured from brain MRI. All participants underwent detailed cognitive and gait assessments. RESULTS: Eighty participants were included (age 44 ± 11, 26 % male); 75 had relapsing-remitting MS (94 %), with disease duration of 8 (11) years [median (IQR)] since MS diagnosis and an Expanded Disability Status Scale (EDSS) of 2.0 (4.0). Higher phase (better dCA) was associated with greater GM volume, lower WHM burden and higher cognitive scores in the memory and global cognitive domains (all P values <0.05). There was no relationship between CVH and gait speed in our study participants. There was no relationship between VR and any measures of brain structure and function. CONCLUSIONS: More efficient cerebral autoregulation is associated with better brain structure (larger GM and lower WMH volumes) and function (cognition, but not gait) in patients with MS.

3.
JAMA Netw Open ; 7(7): e2421485, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38990570

ABSTRACT

Importance: Patients from racial and ethnic minority groups (eg, Asian, Hispanic, and non-Hispanic Black patients) have low representation in clinical trials, especially in phase 1 trials in cancer. These trials represent valuable options for patients with advanced cancer who experience disease progression with standard therapy. Objective: To determine whether the benefit of enrollment to phase 1 cancer trials extends to Asian, Hispanic, and non-Hispanic Black patients as much as it does for non-Hispanic White patients. Data Sources: Patient records at a single institution from January 1999 to December 2016 were reviewed. Treatment-related responses, toxic effects, and deaths were recorded. Study Selection: All phase 1 studies were included. Data Extraction and Synthesis: Data underwent independent extraction by multiple observers following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Main Outcomes and Measures: The primary outcome was overall survival (OS), assessed using univariate and multivariable time-to-event analyses. Results: A total of 738 patients (median [range], 60 [22-93] years; 467 [63.3] female) including 197 Hispanic patients (26.7%), 238 non-Hispanic Black patients (32.2%), and 282 non-Hispanic White patients (38.2%), were enrolled in 64 phase 1 trials, including 33 cytotoxic trials (51.5%), 21 biologic trials (32.8%), and 10 combined therapy trials (15.6%). The primary cancer diagnoses were colorectal (187 patients [25.3%]), ovarian (141 patients [19.1%]), lung (58 patients [7.9%]), uterine (49 patients [6.6%]), and breast (41 patients [5.6%]). Patients underwent a median (range) of 3 (0-13) therapies prior to trial enrollment. Among 558 patients evaluated for response, the clinical benefit rate (ie, stable disease plus response rates) was 49.1%, and the overall response rate was 6.5%. Grade 3 or 4 nonhematological toxic effects were observed in 27.8% (95% CI, 24.6%-31.3%) of patients and grade 3 or 4 hematological toxic effects were observed in 19.7% (95% CI, 17.0%-22.8%) of patients. The treatment-related mortality rate was 0.9% (95% CI, 0.4%-1.9%). Median OS was 9.6 (95% CI, 8.2-11.0) months among Hispanic patients, 8.3 (95% CI, 6.7-10.4) months among non-Hispanic Black patients, and 9.8 (95% CI, 8.5-11.4) months among non-Hispanic White patients (P = .13). In a multivariable analysis, age older than 60 years, Eastern Cooperative Oncology Group performance status score of 2 or greater, more than 2 metastatic sites, lactate dehydrogenase grade 1 or 2, grade 2 or greater low albumin, grade 1 or greater total bilirubin, and grade 2 or greater anemia were associated with worse prognosis, whereas leukocytosis greater than grade 1 was associated with better OS. Conclusions and Relevance: In this meta-analysis assessing outcomes in phase 1 cancer trials among patients from racial and ethnic minority groups, Hispanic and non-Hispanic Black patients had benefits similar to those of non-Hispanic White patients.


Subject(s)
Clinical Trials, Phase I as Topic , Ethnic and Racial Minorities , Neoplasms , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Black or African American , Hispanic or Latino , Neoplasms/ethnology , Neoplasms/mortality , Neoplasms/therapy , Treatment Outcome , Asian , White
4.
EBioMedicine ; 106: 105238, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39002387

ABSTRACT

Most cases of Alzheimer's disease (AD) are late-onset dementias (LOAD). However, research on AD is predominantly of early-onset disease (EOAD). The determinants of EOAD, gene variants of APP and presenilin proteins, are not the basic precursors of LOAD. Rather, multiple other genes and associated cellular processes underlie risk for LOAD. These determinants could be modified in individuals at risk for LOAD well before signs and symptoms appear. Studying brain cells produced from patient-derived induced-pluripotent-stem-cells (iPSC), in culture, will be instrumental in developing such interventions. This paper summarises evidence accrued from iPSC culture models identifying the earliest occurring clinically targetable determinants of LOAD. Results obtained and replicated, thus far, suggest that abnormalities of bioenergetics, lipid metabolism, digestive organelle function and inflammatory activity are primary processes underlying LOAD. The application of cell culture platforms will become increasingly important in research and also on LOAD detection, assessment, and treatment in the years ahead.


Subject(s)
Alzheimer Disease , Induced Pluripotent Stem Cells , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/etiology , Alzheimer Disease/genetics , Humans , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/cytology , Age of Onset , Amyloid beta-Protein Precursor/metabolism , Amyloid beta-Protein Precursor/genetics , Brain/metabolism , Brain/pathology
5.
Foot Ankle Int ; 45(7): 690-697, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38850062

ABSTRACT

BACKGROUND: Primary arthrodesis of Lisfranc fracture-dislocations is a reliable treatment option, yet concerns remain about nonunion. Nitinol staple use has recently proliferated in midfoot arthrodesis. The purpose of this study is to examine the union rate of primary arthrodesis of acute Lisfranc fracture-dislocations treated with nitinol staples compared with traditional plate-and-screw fixation. The secondary objective is to assess the difference in operative times and reoperation rates. METHODS: Midfoot fracture-dislocations treated with primary arthrodesis by 7 foot and ankle orthopaedic surgeons were reviewed. Of 160 eligible patients, 121 patients (305 joints) met the required 4-month minimum radiographic follow-up. Radiographic outcomes were analyzed at the individual joint level. Each joint was classified as either staples alone (45 patients, 154 joints), staples plus plates and screws (hybrid) (45 patients, 40 joints), or plates and screws alone (31 patients, 111 joints). The primary outcome was arthrodesis union at each joint fused. RESULTS: Nonunion was more common (9.0%, 10/111) among joints fixed with plate and screws than with hybrid (2.5%, 1/40) or staples only (1.3%, 2/154) (P = .0085). Multivariable regression demonstrated that autograft use was independent associated with union (P = .0035) and plate-and-screw only fixation was an independent risk factor for nonunion (P = .0407). Median operating room and tourniquet times were shorter for hybrid (92 and 83 minutes) and staple only (67 and 63 minutes) constructs compared to plate-and-screw only fixation (105 and 95 minutes) (P ≤ .0001 and .0003). There was no difference in reoperation rates among patients with different fixation types. CONCLUSION: We found that use of nitinol compression staple and bone autograft in primary arthrodesis of Lisfranc and midfoot fracture-dislocations was associated with both improved union rates and shorter tourniquet and operative times compared to traditional plate-and-screw fixation techniques. LEVEL OF EVIDENCE: Level III, therapeutic.


Subject(s)
Alloys , Arthrodesis , Fracture Fixation, Internal , Arthrodesis/methods , Humans , Female , Male , Middle Aged , Fracture Fixation, Internal/methods , Adult , Retrospective Studies , Bone Screws , Reoperation , Bone Plates , Fracture Dislocation/surgery , Surgical Stapling , Radiography , Sutures , Operative Time
6.
Am J Psychiatry ; 181(7): 591-607, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38685859

ABSTRACT

OBJECTIVE: In this review, the authors update the 2018 position statement of the American Psychiatric Association Council of Research Workgroup on Biomarkers and Novel Treatments on pharmacogenomic (PGx) tools for treatment selection in depression. METHODS: The literature was reviewed for new clinical trials and meta-analyses, published from 2017 to 2022, of studies using PGx tools for treatment selection in depression. The blinding and control conditions, as well as primary and secondary outcomes and post hoc analyses, were summarized. RESULTS: Eleven new clinical trials and five meta-analyses were identified; all studies had primary outcome measures related to speed or efficacy of treatment response. Three trials (27%) demonstrated efficacy on the primary outcome measure with statistical significance; the three studies used different PGx tools; one study was open-label and the other two were small single-blind trials. Five trials (45%) did not detect efficacy with statistical significance on either primary or secondary outcome measures. Only one trial (9%) used adverse events as a primary outcome measure. All studies had significant limitations; for example, none adopted a fully blinded study design, only two studies attempted to blind the treating clinician, and none incorporated measures to estimate the effectiveness of the blinds or the influence of lack of blinding on the study results. CONCLUSIONS: The addition of these new data do not alter the recommendations of the 2018 report, or the advice of the U.S. Food and Drug Administration, that the evidence does not support the use of currently available combinatorial PGx tools for treatment selection in major depressive disorder. Priority efforts for future studies and the development and testing of effective tools include fully blinded study designs, inclusion of promising genetic variants not currently included in any commercially available tests, and investigation of other uses of pharmacogenomics, such as estimating the likelihood of rare adverse drug effects, rather than increasing the speed or magnitude of drug response.


Subject(s)
Pharmacogenetics , Humans , Pharmacogenetics/methods , Antidepressive Agents/therapeutic use , Clinical Trials as Topic , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/genetics , Depressive Disorder/drug therapy , Depressive Disorder/genetics , Pharmacogenomic Testing/methods
7.
J Phys Chem C Nanomater Interfaces ; 128(9): 3632-3640, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38476823

ABSTRACT

Efforts to study intricate, higher-order cellular functions have called for fluorescence imaging under physiologically relevant conditions such as tissue systems in simulated native buffers. This endeavor has presented novel challenges for fluorescent probes initially designed for use in simple buffers and monolayer cell culture. Among current fluorescent probes, semiconductor nanocrystals, or quantum dots (QDs), offer superior photophysical properties that are the products of their nanoscale architectures and chemical formulations. While their high brightness and photostability are ideal for these biological environments, even state of the art QDs can struggle under certain physiological conditions. A recent method correlating electron microscopy ultrastructure with single-QD fluorescence has begun to highlight subtle structural defects in QDs once believed to have no significant impact on photoluminescence (PL). Specific defects, such as exposed core facets, have been shown to quench QD PL in physiologically accurate conditions. For QD-based imaging in complex cellular systems to be fully realized, mechanistic insight and structural optimization of size and PL should be established. Insight from single QD resolution atomic structure and photophysical correlative studies provides a direct course to synthetically tune QDs to match these challenging environments.

8.
J Am Chem Soc ; 146(11): 7487-7497, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38466925

ABSTRACT

Upconverting nanoparticles (UCNPs) exhibit unique nonlinear optical properties that can be harnessed in microscopy, sensing, and photonics. However, forming high-resolution nano- and micropatterns of UCNPs with large packing fractions is still challenging. Additionally, there is limited understanding of how nanoparticle patterning chemistries are affected by the particle size. Here, we explore direct patterning chemistries for 6-18 nm Tm3+-, Yb3+/Tm3+-, and Yb3+/Er3+-based UCNPs using ligands that form either new ionic linkages or covalent bonds between UCNPs under ultraviolet (UV), electron-beam (e-beam), and near-infrared (NIR) exposure. We study the effect of UCNP size on these patterning approaches and find that 6 nm UCNPs can be patterned with compact ionic-based ligands. In contrast, patterning larger UCNPs requires long-chain, cross-linkable ligands that provide sufficient interparticle spacing to prevent irreversible aggregation upon film casting. Compared to approaches that use a cross-linkable liquid monomer, our patterning method limits the cross-linking reaction to the ligands bound on UCNPs deposited as a thin film. This highly localized photo-/electron-initiated chemistry enables the fabrication of densely packed UCNP patterns with high resolutions (∼1 µm with UV and NIR exposure; <100 nm with e-beam). Our upconversion NIR lithography approach demonstrates the potential to use inexpensive continuous-wave lasers for high-resolution 2D and 3D lithography of colloidal materials. The deposited UCNP patterns retain their upconverting, avalanching, and photoswitching behaviors, which can be exploited in patterned optical devices for next-generation UCNP applications.

9.
Ann Clin Transl Neurol ; 11(4): 842-855, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38366285

ABSTRACT

Four sphingosine 1-phosphate (S1P) receptor modulators (fingolimod, ozanimod, ponesimod, and siponimod) are approved by the US Food and Drug Administration for the treatment of multiple sclerosis. This review summarizes efficacy and safety data on these S1P receptor modulators, with an emphasis on similarities and differences. Efficacy data from the pivotal clinical trials are generally similar for the four agents. However, because no head-to-head clinical studies were conducted, direct efficacy comparisons cannot be made. Based on the adverse event profile of S1P receptor modulators, continued and regular monitoring of patients during treatment will be instructive. Notably, the authors recommend paying attention to the cardiac monitoring guidelines for these drugs, and when indicated screening for macular edema and cutaneous malignancies before starting treatment. To obtain the best outcome, clinicians should choose the drug based on disease type, history, and concomitant medications for each patient. Real-world data should help to determine whether there are meaningful differences in efficacy or side effects between these agents.


Subject(s)
Multiple Sclerosis , Sphingosine 1 Phosphate Receptor Modulators , United States , Humans , Multiple Sclerosis/drug therapy , Sphingosine 1 Phosphate Receptor Modulators/adverse effects , Sphingosine-1-Phosphate Receptors/therapeutic use , Fingolimod Hydrochloride/adverse effects , Administration, Oral
10.
Neurol Clin Pract ; 14(1): e200229, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38229875

ABSTRACT

Background and Objectives: Primary mitochondrial myopathies are genetic disorders that primarily affect peripheral skeletal muscles. Patients with primary mitochondrial myopathies often experience muscle weakness, fatigue, and other significant impacts on health-related quality of life. The aim of this noninterventional qualitative study was to collect the most bothersome fatigue-related symptoms and impacts reported by patients with primary mitochondrial myopathies and determine whether the questions included in an existing patient-reported outcome measure, the Modified Fatigue Impact Scale, are relevant and interpretable for this population. Methods: The interviews contained a concept elicitation exercise to understand the most bothersome primary mitochondrial myopathies symptoms and impacts and a cognitive debriefing section to review the questions included in the Modified Fatigue Impact Scale for relevance and interpretability. Transcripts were coded using ATLAS.ti software. Results: Interviews were conducted with 16 patients who were aged 16 years and older with a genetically confirmed and clinical diagnosis of symptomatic primary mitochondrial myopathies. Concept elicitation interviews established that while patients with mitochondrial myopathies reported a wide variety of symptoms and impacts, one of the most impactful symptoms discussed was fatigue. Cognitive debriefing interview results confirmed that the Modified Fatigue Impact Scale items were relevant, were interpretable, and largely captured patients' experience with fatigue. Discussion: Fatigue was one of the most widely discussed experiences discussed by participants and was considered the most important symptom/impact to treat by most of the participants. The Modified Fatigue Impact Scale could be used in future clinical trials to measure treatment benefit in fatigue-related impacts.

11.
Foot Ankle Orthop ; 8(4): 24730114231216985, 2023 Oct.
Article in English | MEDLINE | ID: mdl-38145275

ABSTRACT

Background: The traditional lateral extensile approach to the calcaneus allows for excellent visualization but is associated with high wound complication rates. The sinus tarsi approach has been shown to produce similar radiographic outcomes with much lower rates of wound complications. The purpose of this study is to prospectively determine clinical and radiographic outcomes in calcaneus fractures treated with a sinus tarsi approach. Methods: Twenty-nine patients with 30 calcaneus fractures underwent operative fixation through a sinus tarsi approach and were prospectively evaluated. Routine pre- and postoperative radiographs were obtained, in addition to computed tomography (CT) scans at 6 weeks and 12 months after surgery. Patient-reported outcomes including American Orthopaedic Foot & Ankle Society (AOFAS) score, visual analog scale (VAS) pain score, Veterans Rand 12-Item Health Survey (VR-12), and Foot Functional Index (FFI) were recorded. Patients were followed for a minimum of 1 year postoperation. Results: Twenty-one patients with 22 calcaneus fractures completed 1 year of follow-up. At 12 months postoperation, 20 of 22 patients (91%) had 0 to 2 mm of fracture displacement at the posterior facet on CT scans whereas 2 of 22 patients had 2 to 4 mm of fracture displacement. There was no significant change in posterior facet fracture displacement comparing 6-week and 12-month postoperative CT scans (P > .99). Mean postoperative Bohler angle was 26.1 degrees compared to 13.2 degrees preoperatively. All patients had complete union of fracture site. There were no major wound complications. Four of 22 patients (18.2%) had minor wound complications. AOFAS, FFI, and VAS pain scores improved postoperatively but were not found to correlate with Bohler angle or critical angle of Gissane. Conclusion: We found that in select patients excellent anatomic alignment and good clinical outcomes with low wound complication rates can be achieved when fixing calcaneus fractures through the sinus tarsi approach. Level of Evidence: Level II, prospective cohort study.

12.
Front Psychiatry ; 14: 1218321, 2023.
Article in English | MEDLINE | ID: mdl-38025437

ABSTRACT

Background: The cerebellum contributes to the precise timing of non-motor and motor functions, and cerebellum abnormalities have been implicated in psychosis pathophysiology. In this study, we explored the effects of cerebellar theta burst stimulation (TBS), an efficient transcranial magnetic stimulation protocol, on temporal discrimination and self-reported mood and psychotic symptoms. Methods: We conducted a case-crossover study in which patients with psychosis (schizophrenias, schizoaffective disorders, or bipolar disorders with psychotic features) were assigned to three sessions of TBS to the cerebellar vermis: one session each of intermittent (iTBS), continuous (cTBS), and sham TBS. Of 28 enrolled patients, 26 underwent at least one TBS session, and 20 completed all three. Before and immediately following TBS, participants rated their mood and psychotic symptoms and performed a time interval discrimination task (IDT). We hypothesized that cerebellar iTBS and cTBS would modulate these measures in opposing directions, with iTBS being adaptive and cTBS maladaptive. Results: Reaction time (RT) in the IDT decreased significantly after iTBS vs. Sham (LS-mean difference = -73.3, p = 0.0001, Cohen's d = 1.62), after iTBS vs. cTBS (LS-mean difference = -137.6, p < 0.0001, d = 2.03), and after Sham vs. cTBS (LS-mean difference = -64.4, p < 0.0001, d = 1.33). We found no effect on IDT accuracy. We did not observe any effects on symptom severity after correcting for multiple comparisons. Conclusion: We observed a frequency-dependent dissociation between the effects of iTBS vs. cTBS to the cerebellar midline on the reaction time of interval discrimination in patients with psychosis. iTBS showed improved (adaptive) while cTBS led to worsening (maladaptive) speed of response. These results demonstrate behavioral target engagement in a cognitive dimension of relevance to patients with psychosis and generate testable hypotheses about the potential therapeutic role of cerebellar iTBS in this clinical population. Clinical Trial Registration: clinicaltrials.gov, identifier NCT02642029.

13.
Neurol Clin Pract ; 13(5): e200182, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37664132

ABSTRACT

Purpose of Review: Tumor-like brain lesions are rare and commonly suggest a neoplastic etiology. Failure to rapidly identify non-neoplastic causes can lead to increased morbidity and mortality. In this review, we describe 10 patients who presented with atypical, non-neoplastic tumor-like brain lesions in which brain biopsy was essential for a correct diagnosis and treatment. Recent Findings: There has been increasing recognition of autoimmune conditions affecting the nervous system, and many of those diseases can cause tumor-like brain lesions. Currently available reports of non-neoplastic tumor-like brain lesions are scarce. Most case series focus on tumefactive demyelinating lesions, and a comprehensive review including other neuroimmunological conditions such as CNS vasculitis, neurosarcoidosis, histiocytic and infectious etiologies is lacking. Summary: We review the literature on tumor-like brain lesions intending to increase the awareness and differential diagnosis of non-neoplastic brain tumor mimics. We advocate for earlier brain biopsies, which, in our case series, significantly changed diagnosis, management, and outcomes.

14.
Nanotechnology ; 35(1)2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37703845

ABSTRACT

Scanning transmission electron microscopy is a common tool used to study the atomic structure of materials. It is an inherently multimodal tool allowing for the simultaneous acquisition of multiple information channels. Despite its versatility, however, experimental workflows currently rely heavily on experienced human operators and can only acquire data from small regions of a sample at a time. Here, we demonstrate a flexible pipeline-based system for high-throughput acquisition of atomic-resolution structural data using an all-piezo sample stage applied to large-scale imaging of nanoparticles and multimodal data acquisition. The system is available as part of the user program of the Molecular Foundry at Lawrence Berkeley National Laboratory.

17.
Nano Lett ; 23(15): 7001-7007, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37493432

ABSTRACT

The rapid photobleaching of near-infrared (NIR) dye-sensitized upconversion nanosystems is one of the crucial problems that has blocked their technological applications. Uncovering the photophysical and photochemical pathways of NIR dyes would help to elucidate the photobleaching mechanism and thereby improve the photostability of the system. Here we investigate the triplet dynamics of NIR dyes and their interaction with triplet oxygen in the typically investigated IR806-sensitized upconversion nanoparticle (UCNP) nanosystem. Low-temperature fluorescence at 77 K provides direct proof of the generation of singlet oxygen (1O2) under 808 nm laser irradiation. Mass spectrometry indicates that all three double bonds in the structure of IR806 can be broken in the photochemical process. Coupling IR806 to the surface of UCNPs can accelerate its triplet dynamics, thus producing more 1O2 to photocleave IR806. Importantly, we find that the addition of ß-carotene can scavenge the generated 1O2, thereby providing a simple method to effectively inhibit photobleaching.

18.
Nat Commun ; 14(1): 4283, 2023 07 18.
Article in English | MEDLINE | ID: mdl-37463889

ABSTRACT

The nuclear receptor, Nurr1, is critical for both the development and maintenance of midbrain dopamine neurons, representing a promising molecular target for Parkinson's disease (PD). We previously identified three Nurr1 agonists (amodiaquine, chloroquine and glafenine) that share an identical chemical scaffold, 4-amino-7-chloroquinoline (4A7C), suggesting a structure-activity relationship. Herein we report a systematic medicinal chemistry search in which over 570 4A7C-derivatives were generated and characterized. Multiple compounds enhance Nurr1's transcriptional activity, leading to identification of an optimized, brain-penetrant agonist, 4A7C-301, that exhibits robust neuroprotective effects in vitro. In addition, 4A7C-301 protects midbrain dopamine neurons in the MPTP-induced male mouse model of PD and improves both motor and non-motor olfactory deficits without dyskinesia-like behaviors. Furthermore, 4A7C-301 significantly ameliorates neuropathological abnormalities and improves motor and olfactory dysfunctions in AAV2-mediated α-synuclein-overexpressing male mouse models. These disease-modifying properties of 4A7C-301 may warrant clinical evaluation of this or analogous compounds for the treatment of patients with PD.


Subject(s)
Neuroprotective Agents , Parkinson Disease , Mice , Animals , Male , Parkinson Disease/drug therapy , Parkinson Disease/pathology , Dopaminergic Neurons/metabolism , Mesencephalon/metabolism , Brain/metabolism , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Disease Models, Animal , Nuclear Receptor Subfamily 4, Group A, Member 2/genetics , Nuclear Receptor Subfamily 4, Group A, Member 2/metabolism
19.
Nano Lett ; 23(15): 7100-7106, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37471584

ABSTRACT

Photon avalanching nanoparticles (ANPs) exhibit extremely nonlinear upconverted emission valuable for subdiffraction imaging, nanoscale sensing, and optical computing. Avalanching has been demonstrated with Tm3+-, Pr3+-, or Nd3+-doped nanocrystals, but their emission is limited to a few wavelengths and materials. Here, we utilize Gd3+-assisted energy migration to tune the emission wavelengths of Tm3+-sensitized ANPs and generate highly nonlinear emission from Eu3+, Tb3+, Ho3+, and Er3+ ions. The upconversion intensities of these spectrally discrete ANPs scale with nonlinearity factor s = 10-17 under 1064 nm excitation at power densities as low as 7 kW cm-2. This strategy for imprinting avalanche behavior on remote emitters can be extended to fluorophores adjacent to ANPs, as we demonstrate with CdS/CdSe/CdS core/shell/shell quantum dots. ANPs with rationally designed energy transfer networks provide the means to transform conventional linear emitters into a highly nonlinear ones, expanding the use of photon avalanching in biological, chemical, and photonic applications.

20.
Harv Rev Psychiatry ; 31(4): 208-213, 2023.
Article in English | MEDLINE | ID: mdl-37437253

ABSTRACT

ABSTRACT: Physician medical directors working for health care insurance companies conduct utilization reviews, participate in quality-of-care reviews, and adjudicate appeals. As a result, they have access to substantial and important clinical information. The medical director may have both current and historical information that can assist the treatment team in providing care. Sharing this information with a patient's current health care provider(s) is problematic due to concerns about patient privacy and the insurer's goal of not assuming legal liability for patient care. While this paper considers legal issues, it predominantly addresses the ethical responsibilities of medical directors who have valuable information unavailable to or unrecognized by the treatment team. Although it is important to consider sharing general medical information, this paper emphasizes the sharing of behavioral health information, which can be highly sensitive but also pertinent to psychiatric and other medical treatment choices. We suggest that clinical information should flow from insurer to provider when the insurer has information that will benefit the patient or prove crucial to optimal care rather than just flow from provider to insurer for the purposes of claims payments. To support and secure that flow, the paper outlines procedures for determining the need to share information, the means of providing that information, ways to separate liability, and processes for protecting privacy.


Subject(s)
Insurance , Psychiatry , Humans , Health Personnel
SELECTION OF CITATIONS
SEARCH DETAIL