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1.
bioRxiv ; 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38586051

ABSTRACT

We have combined MR histology and light sheet microscopy (LSM) of five postmortem C57BL/6J mouse brains in a stereotaxic space based on micro-CT yielding a multimodal 3D atlas with the highest spatial and contrast resolution yet reported. Brains were imaged in situ with multi gradient echo (mGRE) and diffusion tensor imaging (DTI) at 15 µm resolution (∼ 2.4 million times that of clinical MRI). Scalar images derived from the average DTI and mGRE provide unprecedented contrast in 14 complementary 3D volumes, each highlighting distinct histologic features. The same tissues scanned with LSM and registered into the stereotaxic space provide 17 different molecular cell type stains. The common coordinate framework labels (CCFv3) complete the multimodal atlas. The atlas has been used to correct distortions in the Allen Brain Atlas and harmonize it with Franklin Paxinos. It provides a unique resource for stereotaxic labeling of mouse brain images from many sources.

2.
Bioorg Chem ; 146: 107289, 2024 May.
Article in English | MEDLINE | ID: mdl-38493636

ABSTRACT

Structurally diverse cyclopenta[4,5]pyrrolo[1,2-a]indoles heterocycles were smoothly constructed in good to excellent yields (up to 99 %) with excellent diastereoselectivities (>19:1 dr) through a novel and facile strategy based on BF3-catalyzed Friedel-Crafts alkylation/Aldol/Dehydrative cyclization cascade reaction. The anti-proliferative activity of these newly synthesized polycyclic indoles was screened, and all the functionalized reductive derivatives exhibited favorable anti-tumor activity. Notably, compound 4ae displayed the remarkable inhibitory activity against MCF-7 and HeLa cells with IC50 values of 4.62 µM and 7.71 µM, respectively. Mechanistically, the representative compound 4ae could effectively induce apoptosis of MCF-7 cells in crediting to up-regulate the relative expression of apoptotic protein BAX/Bcl-2, subsequently activate Pro-caspase 9 and cleave PARP, simultaneously block the cell cycle through down- and up-regulate the expression of cyclin B1 and p53, respectively. Moreover, compound 4ae also exhibited promising antineoplastic efficacy in subcutaneous MCF-7 xenograft mice which manifest significant shrunken tumors conspicuous nuclear apoptotic signal and minimal systemic toxicity. This strategy not only established a novel and efficient method for the assembly of structurally complex indole heterocycles, but also provided a series of compounds possessing attractive anti-cancer activity, which holds immense potential for future biomedical applications.


Subject(s)
Antineoplastic Agents , Animals , Humans , Mice , Antineoplastic Agents/pharmacology , Apoptosis , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Drug Screening Assays, Antitumor , HeLa Cells , Indoles/pharmacology , MCF-7 Cells , Molecular Structure , Polycyclic Compounds/chemical synthesis , Polycyclic Compounds/chemistry , Polycyclic Compounds/pharmacology
3.
J Cell Physiol ; 239(1): 3-19, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38032002

ABSTRACT

Meiosis is a specialized cell division that occurs in sexually reproducing organisms, generating haploid gametes containing half the chromosome number through two rounds of cell division. Homologous chromosomes pair and prepare for their proper segregation in subsequent divisions. How homologous chromosomes recognize each other and achieve pairing is an important question. Early studies showed that in most organisms, homologous pairing relies on homologous recombination. However, pairing mechanisms differ across species. Evidence indicates that chromosomes are dynamic and move during early meiotic stages, facilitating pairing. Recent studies in various model organisms suggest conserved mechanisms and key regulators of homologous chromosome pairing. This review summarizes these findings and compare similarities and differences in homologous chromosome pairing mechanisms across species.


Subject(s)
Chromosome Pairing , Chromosome Segregation , Meiosis , Chromosome Pairing/genetics , Chromosome Segregation/genetics , Chromosomes , Homologous Recombination , Meiosis/genetics
4.
J Cell Biol ; 223(2)2024 02 05.
Article in English | MEDLINE | ID: mdl-38010234

ABSTRACT

During meiosis, cohesin and meiosis-specific proteins organize chromatin into an axis-loop architecture, coordinating homologous synapsis, recombination, and ordered chromosome segregation. However, how the meiotic chromosome axis is assembled and differentiated with meiotic progression remains elusive. Here, we explore the dynamic recruitment of two long arms of the bivalent proteins, LAB-1 and LAB-2, in Caenorhabditis elegans. LAB proteins directly interact with the axis core HORMA complexes and weak interactions contribute to their recruitment. LAB proteins phase separate in vitro, and this capacity is promoted by HORMA complexes. During early prophase, synapsis oppositely regulates the axis enrichment of LAB proteins. After the pachytene exit, LAB proteins switch from a reciprocal localization pattern to a colocalization pattern, and the normal dynamic pattern of LAB proteins is altered in meiotic mutants. We propose that LAB recruitment senses axis differentiation, and phase separation of meiotic structures helps subdomain establishment and accurate segregation of the chromosomes.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Chromosomal Proteins, Non-Histone , Meiosis , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Chromosome Pairing/genetics , Chromosome Segregation , Chromosomes/genetics , Chromosomes/metabolism , Chromosomal Proteins, Non-Histone/genetics , Chromosomal Proteins, Non-Histone/metabolism
5.
Front Neurosci ; 17: 1223226, 2023.
Article in English | MEDLINE | ID: mdl-37841684

ABSTRACT

Information on regional variation in cell numbers and densities in the CNS provides critical insight into structure, function, and the progression of CNS diseases. However, variability can be real or a consequence of methods that do not account for technical biases, including morphologic deformations, errors in the application of cell type labels and boundaries of regions, errors of counting rules and sampling sites. We address these issues in a mouse model by introducing a workflow that consists of the following steps: 1. Magnetic resonance histology (MRH) to establish the size, shape, and regional morphology of the mouse brain in situ. 2. Light-sheet microscopy (LSM) to selectively label neurons or other cells in the entire brain without sectioning artifacts. 3. Register LSM volumes to MRH volumes to correct for dissection errors and both global and regional deformations. 4. Implement stereological protocols for automated sampling and counting of cells in 3D LSM volumes. This workflow can analyze the cell densities of one brain region in less than 1 min and is highly replicable in cortical and subcortical gray matter regions and structures throughout the brain. This method demonstrates the advantage of not requiring an extensive amount of training data, achieving a F1 score of approximately 0.9 with just 20 training nuclei. We report deformation-corrected neuron (NeuN) counts and neuronal density in 13 representative regions in 5 C57BL/6J cases and 2 BXD strains. The data represent the variability among specimens for the same brain region and across regions within the specimen. Neuronal densities estimated with our workflow are within the range of values in previous classical stereological studies. We demonstrate the application of our workflow to a mouse model of aging. This workflow improves the accuracy of neuron counting and the assessment of neuronal density on a region-by-region basis, with broad applications for studies of how genetics, environment, and development across the lifespan impact cell numbers in the CNS.

7.
Biometrics ; 79(4): 3764-3777, 2023 12.
Article in English | MEDLINE | ID: mdl-37459181

ABSTRACT

Continuous response data are regularly transformed to meet regression modeling assumptions. However, approaches taken to identify the appropriate transformation can be ad hoc and can increase model uncertainty. Further, the resulting transformations often vary across studies leading to difficulties with synthesizing and interpreting results. When a continuous response variable is measured repeatedly within individuals or when continuous responses arise from clusters, analyses have the additional challenge caused by within-individual or within-cluster correlations. We extend a widely used ordinal regression model, the cumulative probability model (CPM), to fit clustered, continuous response data using generalized estimating equations for ordinal responses. With the proposed approach, estimates of marginal model parameters, cumulative distribution functions , expectations, and quantiles conditional on covariates can be obtained without pretransformation of the response data. While computational challenges arise with large numbers of distinct values of the continuous response variable, we propose feasible and computationally efficient approaches to fit CPMs under commonly used working correlation structures. We study finite sample operating characteristics of the estimators via simulation and illustrate their implementation with two data examples. One studies predictors of CD4:CD8 ratios in a cohort living with HIV, and the other investigates the association of a single nucleotide polymorphism and lung function decline in a cohort with early chronic obstructive pulmonary disease.


Subject(s)
Models, Statistical , Humans , Computer Simulation , Probability , Uncertainty
8.
bioRxiv ; 2023 May 17.
Article in English | MEDLINE | ID: mdl-37292796

ABSTRACT

Information on regional variation in cell numbers and densities in the CNS provides critical insight into structure, function, and the progression of CNS diseases. However, variability can be real or can be a consequence of methods that do not account for technical biases, including morphologic deformations, errors in the application of cell type labels and boundaries of regions, errors of counting rules and sampling sites. We address these issues of by introducing a workflow that consists of the following steps: 1. Magnetic resonance histology (MRH) to establish the size, shape, and regional morphology of the mouse brain in situ. 2. Light-sheet microscopy (LSM) to selectively label all neurons or other cells in the entire brain without sectioning artifacts. 3. Register LSM volumes to MRH volumes to correct for dissection errors and morphological deformations. 4. Implement novel protocol for automated sampling and counting of cells in 3D LSM volumes. This workflow can analyze the cells density of one brain region in less than 1 min and is highly replicable to cortical and subcortical gray matter regions and structures throughout the brain. We report deformation-corrected neuron (NeuN) counts and neuronal density in 13 representative regions in 5 C57B6/6J and 2 BXD strains. The data represent the variability among cases for the same brain region and across regions within case. Our data are consistent with previous studies. We demonstrate the application of our workflow to a mouse model of aging. This workflow improves the accuracy of neuron counting and the assessment of neuronal density on a region-by-region basis, with broad applications in how genetics, environment, and development across the lifespan impact brain structure.

9.
Biol Res Nurs ; 25(4): 635-646, 2023 10.
Article in English | MEDLINE | ID: mdl-37210672

ABSTRACT

Objectives: To explore whether tai chi can improve lung function, exercise capacity, and health-related outcomes in patients with chronic obstructive pulmonary disease (COPD). Methods: The PubMed, Embase, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure (CNKI), Wanfang, and China Science and Technology Journal Database (VIP) databases were searched from inception to January 5, 2023. The methodological quality of the included studies was evaluated according to the Cochrane Handbook for Systematic Reviews of Interventions criteria. Results: A total of 1430 participants from 20 randomized controlled trials were included in this review. The results indicated significant effects of tai chi on FEV1, 6WMD, anxiety, and quality of life (p < 0.01), but not on FEV1%, FEVI/FVC, depression, and social support. Conclusions: Tai chi might be a potential alternative therapy to improve FEV1, 6WMD, anxiety, and quality of life for patients with COPD.


Subject(s)
Pulmonary Disease, Chronic Obstructive , Tai Ji , Humans , Exercise Tolerance , Quality of Life , Randomized Controlled Trials as Topic , Pulmonary Disease, Chronic Obstructive/therapy , Lung
10.
Proc Natl Acad Sci U S A ; 120(17): e2218617120, 2023 04 25.
Article in English | MEDLINE | ID: mdl-37068254

ABSTRACT

We have developed workflows to align 3D magnetic resonance histology (MRH) of the mouse brain with light sheet microscopy (LSM) and 3D delineations of the same specimen. We start with MRH of the brain in the skull with gradient echo and diffusion tensor imaging (DTI) at 15 µm isotropic resolution which is ~ 1,000 times higher than that of most preclinical MRI. Connectomes are generated with superresolution tract density images of ~5 µm. Brains are cleared, stained for selected proteins, and imaged by LSM at 1.8 µm/pixel. LSM data are registered into the reference MRH space with labels derived from the ABA common coordinate framework. The result is a high-dimensional integrated volume with registration (HiDiver) with alignment precision better than 50 µm. Throughput is sufficiently high that HiDiver is being used in quantitative studies of the impact of gene variants and aging on mouse brain cytoarchitecture and connectomics.


Subject(s)
Diffusion Tensor Imaging , Microscopy , Mice , Animals , Diffusion Tensor Imaging/methods , Magnetic Resonance Imaging/methods , Brain/diagnostic imaging , Magnetic Resonance Spectroscopy , Diffusion Magnetic Resonance Imaging/methods
11.
Food Microbiol ; 113: 104277, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37098434

ABSTRACT

Vibrio parahaemolyticus is an increasingly important foodborne pathogen that cause acute gastroenteritis in humans. However, the prevalence and transmission of this pathogen in freshwater food remains unclear. This study aimed to determine the molecular characteristics and genetic relatedness of V. parahaemolyticus isolates obtained from freshwater food, seafood, environmental, and clinical samples. A total of 138 (46.6%) isolates were detected from 296 food and environmental samples, and 68 clinical isolates from patients. Notably, V. parahaemolyticus was more prevalent in freshwater food (56.7%, 85/150) than in seafood (38.8%, 49/137). Virulence phenotype analyses revealed that the high motility of isolates from freshwater food (40.0%) and clinical isolates (42.0%) was higher than that of isolates from seafood (12.2%), whereas the biofilm-forming capacity of freshwater food isolates (9.4%) was lower than that of seafood (22.4%) and clinical isolates (15.9%). Virulence genes analysis showed that 46.4% of the clinical isolates contained the tdh gene encoding thermostable direct hemolysin (TDH) and only two freshwater food isolates contained the trh gene encoding TDH-related hemolysin (TRH). Multilocus sequence typing (MLST) analysis divided the 206 isolates into 105 sequence types (STs), including 56 (53.3%) novel STs. ST2583, ST469, and ST453 have been isolated from freshwater food and clinical samples. Whole-genome sequence (WGS) analyses revealed that the 206 isolates were divided into five clusters. Cluster II contained isolates from freshwater food and clinical samples, whereas the other clusters contained isolates from seafood, freshwater food, and clinical samples. In addition, we observed that ST2516 had the same virulence pattern, with a close phylogenetic relationship to ST3. The increased prevalence and adaption of V. parahaemolyticus in freshwater food is a potential cause of clinical cases closely related to the consumption of V. parahaemolyticus contaminated freshwater food.


Subject(s)
Vibrio Infections , Vibrio parahaemolyticus , Humans , Multilocus Sequence Typing , Phylogeny , Seafood , Genomics
12.
Mathematics (Basel) ; 11(24)2023 Dec 02.
Article in English | MEDLINE | ID: mdl-38374966

ABSTRACT

Regression models for continuous outcomes frequently require a transformation of the outcome, which is often specified a priori or estimated from a parametric family. Cumulative probability models (CPMs) nonparametrically estimate the transformation by treating the continuous outcome as if it is ordered categorically. They thus represent a flexible analysis approach for continuous outcomes. However, it is difficult to establish asymptotic properties for CPMs due to the potentially unbounded range of the transformation. Here we show asymptotic properties for CPMs when applied to slightly modified data where bounds, one lower and one upper, are chosen and the outcomes outside the bounds are set as two ordinal categories. We prove the uniform consistency of the estimated regression coefficients and of the estimated transformation function between the bounds. We also describe their joint asymptotic distribution, and show that the estimated regression coefficients attain the semiparametric efficiency bound. We show with simulations that results from this approach and those from using the CPM on the original data are very similar when a small fraction of the data are modified. We reanalyze a dataset of HIV-positive patients with CPMs to illustrate and compare the approaches.

13.
Opt Express ; 30(26): 46722-46733, 2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36558617

ABSTRACT

With the developments of the tunable laser source (TLS), there are increasing demands for high-resolution dynamic wavelength calibration in recent years. Considering mutual constraints between wide measurement range and high calibration resolution, we propose a dynamic wavelength calibration method based on an auxiliary Mach-Zehnder interferometer (MZI) and the synchrosqueezed wavelet transform (SSWT). Our proposed method can achieve a calibration resolution of 5 fm and a tuning range of 10 nm. Moreover, the measurement range and spatial resolution of the optical frequency domain reflectometer (OFDR) system are improved to ∼80 m and ∼mm, respectively. Our proposed approach can substantially reduce the subtle spectrum distortion (tens of fm) in coherent optical spectrum analyzer (COSA) systems.

14.
Front Psychol ; 13: 986800, 2022.
Article in English | MEDLINE | ID: mdl-36051203

ABSTRACT

As the autonomous vehicles technology gradually enters the public eye, understanding consumers' psychological motivations for accepting autonomous vehicles is critical for the development of autonomous vehicles and society. Previously, researchers have explored the determinants of fully autonomous vehicles but the relevant research is far from enough. Moreover, the relationship between anthropomorphism and users' behavior has been ignored to a large extent. Therefore, this study aim to fill the gap by using anthropomorphism and the unified theory of acceptance and use of technology (UTAUT) to explore how system attributes (i.e., perceived anthropomorphism, perceived intelligence) and UTAUT attributes influence consumers' acceptance behavior. The data were collected via questionnaire survey conducted in Beijing, China, which can be a promising early adopter of AVs. Structural equation modeling was used to analyze the data. The results reveal that perceived anthropomorphism and perceived intelligence have a direct positive influence on the adoption of AVs; performance expectancy, effort expectancy, and facilitating conditions have an indirect positive influence on intention to adopt AVs. Also, this research contributes to the literature by enriching studies on psychological determinants of autonomous vehicles' adoption by taking an initial step to highlight anthropomorphism perceptions. This can provide managerial implications for policy-makers and businesses on how to effectively allocate resources to enhance autonomous vehicle adoption.

15.
Sensors (Basel) ; 22(14)2022 Jul 19.
Article in English | MEDLINE | ID: mdl-35891063

ABSTRACT

Optical fiber measurement technology is widely used in the strength testing of buildings, the health testing of industrial equipment, and the minimally invasive surgery of modern medical treatment due to its characteristics of free calibration, high precision, and small size. This paper presents an algorithm that can improve the range and stability of strain measurements in order to solve the problems of the small range and measurement failure of optical fiber strain sensors based on optical frequency-domain reflectometry (OFDR). Firstly, a Rayleigh scattering model based on the refractive index perturbation of an optical fiber is proposed to study the characteristics of Rayleigh scattering and to guide the strain demodulation algorithm based on the spectral shift. Secondly, a local similar scanning method that can maintain a high similarity by monitoring local Rayleigh scattering signals (LSs) before and after strain is proposed. Thirdly, a generalized cross-correlation algorithm is proposed to detect spectral offset, solving the problem of demodulation failure in the case of a Rayleigh scattering signal with a low signal-to-noise ratio. Experiments show that the proposed method still has high stability when the spatial resolution is 3 mm. The measurement precision is 6.2 µÎµ, which proves that the multi-peaks or pseudo-peaks of the traditional algorithm in the case of a large strain, the high spatial resolution, and the poor signal-to-noise ratio are solved, and the stability of the strain measurement process is improved.


Subject(s)
Optical Fibers , Refractometry
16.
PLoS One ; 17(6): e0270565, 2022.
Article in English | MEDLINE | ID: mdl-35763519

ABSTRACT

Across rural sub-Saharan Africa, people living with HIV (PLHIV) commonly seek out treatment from traditional healers. We report on the clinical outcomes of a community health worker intervention adapted for traditional healers with insight into our results from qualitative interviews. We employed a pre-post intervention study design and used sequential mixed methods to assess the impact of a traditional healer support worker intervention in Zambézia province, Mozambique. After receiving a positive test result, 276 participants who were newly enrolled in HIV treatment and were interested in receiving home-based support from a traditional healer were recruited into the study. Those who enrolled from February 2016 to August 2016 received standard of care services, while those who enrolled from June 2017 to May 2018 received support from a traditional healer. We conducted interviews among healers and participants to gain insight into fidelity of study activities, barriers to support, and program improvement. Medication possession ratio at home (based on pharmacy pick-up dates) was not significantly different between pre- and post-intervention participants (0.80 in the pre-intervention group compared to 0.79 in the post-intervention group; p = 0.96). Participants reported receiving educational and psychosocial support from healers. Healers adapted their support protocol to initiate directly observed therapy among participants with poor adherence. Traditional healers can provide community-based psychosocial support, education, directly observed therapy, and disclosure assistance for PLHIV. Multiple factors may hinder patients' desire and ability to remain adherent to treatment, including poverty, confusion about medication side effects, and frustration with wait times at the health facility.


Subject(s)
HIV Infections , Medicine, African Traditional , HIV Infections/drug therapy , HIV Infections/psychology , Health Facilities , Humans , Medicine, African Traditional/methods , Mozambique , Rural Population
17.
Sci Rep ; 12(1): 5940, 2022 04 08.
Article in English | MEDLINE | ID: mdl-35396532

ABSTRACT

Recently developed descanned versions of the oblique light-sheet microscope promise to enable high-frame rate volumetric imaging in a variety of convenient preparations. The efficiency of these microscopes depends on the implementation of the objective coupling that turns the intermediate imaging plane. In this work, we developed a fully immersed coupling strategy between the middle and end objectives of the oblique light-sheet microscope to enable facile alignment and high efficiency coupling. Our design outperformed conventional designs that used only air objectives in resolution and light-collection power. We further demonstrated our design's ability to capture large fields-of-view when paired with a camera with built-in electronic binning. We simultaneously imaged the forebrain and hindbrain of larval zebrafish and found clusters of activity localized to each region of the brain.


Subject(s)
Water , Zebrafish , Animals , Brain/diagnostic imaging , Larva , Microscopy/methods
18.
Appl Opt ; 61(4): 1030-1034, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-35201075

ABSTRACT

The laser scanning interferometry system has been successfully applied to many measurement fields because of its efficient measurement ability. However, the practical application ability of this measurement method is restricted due to the laser tuning nonlinearity. In this paper, the fiber ring resonator is equidistant in the frequency domain, which is used as the external clock signal to resample the main interference signal so as to realize the equifrequency sampling of the laser scanning interference system and correct the tuning nonlinearity. The final experimental result shows that this method can effectively reduce the phase noise caused by tuning nonlinearity and improve the performance of the system.

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