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1.
Evolution ; 78(2): 355-363, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37952174

ABSTRACT

Although sex determination is ubiquitous in vertebrates, mechanisms of sex determination vary from environmentally to genetically influenced. In vertebrates, genetic sex determination is typically accomplished with sex chromosomes. Groups like mammals maintain conserved sex chromosome systems, while sex chromosomes in most vertebrate clades are not conserved across similar evolutionary timescales. One group inferred to have an evolutionarily stable mode of sex determination is Anguimorpha, a clade of charismatic taxa including monitor lizards, Gila monsters, and crocodile lizards. The common ancestor of extant anguimorphs possessed a ZW system that has been retained across the clade. However, the sex chromosome system in the endangered, monotypic family of crocodile lizards (Shinisauridae) has remained elusive. Here, we analyze genomic data to demonstrate that Shinisaurus has replaced the ancestral anguimorph ZW system on LG7 with a novel ZW system on LG3. The linkage group, LG3, corresponds to chromosome 9 in chicken, and this is the first documented use of this syntenic block as a sex chromosome in amniotes. Additionally, this ~1 Mb region harbors approximately 10 genes, including a duplication of the sex-determining transcription factor, Foxl2, critical for the determination and maintenance of sexual differentiation in vertebrates, and thus a putative primary sex-determining gene for Shinisaurus.


Subject(s)
Lizards , Animals , Lizards/genetics , Sex Chromosomes , Snakes/genetics , Genome , Genomics , Sex Determination Processes , Mammals/genetics
2.
Clin Immunol ; 257: 109842, 2023 12.
Article in English | MEDLINE | ID: mdl-37981105

ABSTRACT

Cardinal features of lupus include elevated B cell activation and autoantibody production with a female sex preponderance. We quantified interactions of sex and genetic variation on the development of autoimmune B-cell phenotypes and autoantibodies in the BXD2 murine model of lupus using a cohort of backcrossed progeny (BXD2 x C57BL/6J) x BXD2. Sex was the key factor leading to increased total IgG, IgG2b, and autoantibodies. The percentage of T-bet+CD11c+ IgD+ activated naive B cells (aNAV) was higher in females and was associated with increased T-bet+CD11c+ IgD- age-related B cells, Fas+GL7+ germinal center B cells, Cxcr5-Icos+ peripheral T-helper cells, and Cxcr5+Icos+ follicular T-helper cells. IFN-ß was elevated in females. Variation in aNAV cells was mapped to Chr 7 in a locus that shows significant interactions between the female sex and heterozygous B/D variant. Our results suggest that activation of naive B cells forms the basis for the female-predominant development of autoantibodies in lupus-susceptible BXD2 mice.


Subject(s)
B-Lymphocytes , Lupus Erythematosus, Systemic , Animals , Female , Humans , Male , Mice , Autoantibodies , Crosses, Genetic , Germinal Center , Lupus Erythematosus, Systemic/genetics , Mice, Inbred C57BL , T-Lymphocytes, Helper-Inducer , Sex Characteristics
3.
JACC Clin Electrophysiol ; 9(9): 2024-2033, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37480874

ABSTRACT

Myocarditis is frequently associated with viral infections. Increasing evidence points to an association between myocarditis and inherited cardiomyopathies, though it is unclear whether myocarditis is a driver or an accessory. We present a primary vignette and case series highlighting recurrent myocarditis in patients later found to harbor pathogenic desmosomal variants and provide clinical and basic science context, exploring 2 potentially overlapping hypotheses: that stress induces cellular injury and death in structurally abnormal myocytes and that recurrent viral myocardial and truncated desomosomal protein byproducts as 2 hits could lead to loss of immune tolerance and subsequent autoreactivity.

4.
bioRxiv ; 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37461522

ABSTRACT

Although sex determination is ubiquitous in vertebrates, mechanisms of sex determination vary from environmentally- to genetically-influenced. In vertebrates, genetic sex determination is typically accomplished with sex chromosomes. Groups like mammals maintain conserved sex chromosome systems, while sex chromosomes in most vertebrate clades aren't conserved across similar evolutionary timescales. One group inferred to have an evolutionarily stable mode of sex determination is Anguimorpha, a clade of charismatic taxa including: monitor lizards, Gila monsters, and crocodile lizards. The common ancestor of extant anguimorphs possessed a ZW system that has been retained across the clade. However, the sex chromosome system in the endangered, monotypic family of crocodile lizards (Shinisauridae) has remained elusive. Here, we analyze genomic data to demonstrate that Shinisaurus has replaced the ancestral anguimorph ZW system on LG7 chromosome with a novel ZW system on LG3. The linkage group LG3 corresponds to chromosome 9 in chicken, and this is the first documented use of this syntenic block as a sex chromosome in amniotes. Additionally, this ~1Mb region harbors approximately 10 genes, including a duplication of the sex-determining transcription factor, Foxl2-critical for the determination and maintenance of sexual differentiation in vertebrates, and thus a putative primary sex determining gene for Shinisaurus.

5.
Crit Care ; 27(1): 234, 2023 06 13.
Article in English | MEDLINE | ID: mdl-37312169

ABSTRACT

Angiopoietin-2 (Ang-2) is associated with vascular endothelial injury and permeability in the acute respiratory distress syndrome (ARDS) and sepsis. Elevated circulating Ang-2 levels may identify critically ill patients with distinct pathobiology amenable to targeted therapy. We hypothesized that plasma Ang-2 measured shortly after hospitalization among patients with sepsis would be associated with the development of ARDS and poor clinical outcomes. To test this hypothesis, we measured plasma Ang-2 in a cohort of 757 patients with sepsis, including 267 with ARDS, enrolled in the emergency department or early in their ICU course before the COVID-19 pandemic. Multivariable models were used to test the association of Ang-2 with the development of ARDS and 30-day morality. We found that early plasma Ang-2 in sepsis was associated with higher baseline severity of illness, the development of ARDS, and mortality risk. The association between Ang-2 and mortality was strongest among patients with ARDS and sepsis as compared to those with sepsis alone (OR 1.81 vs. 1.52 per log Ang-2 increase). These findings might inform models testing patient risk prediction and strengthen the evidence for Ang-2 as an appealing biomarker for patient selection for novel therapeutic agents to target vascular injury in sepsis and ARDS.


Subject(s)
COVID-19 , Respiratory Distress Syndrome , Sepsis , Humans , Angiopoietin-2 , Critical Illness , Pandemics , Prognosis
6.
Nat Photonics ; 17(3): 250-258, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37143962

ABSTRACT

Widefield microscopy of optically thick specimens typically features reduced contrast due to "spatial crosstalk", in which the signal at each point in the field of view is the result of a superposition from neighbouring points that are simultaneously illuminated. In 1955, Marvin Minsky proposed confocal microscopy as a solution to this problem. Today, laser scanning confocal fluorescence microscopy is broadly used due to its high depth resolution and sensitivity, but comes at the price of photobleaching, chemical, and photo-toxicity. Here, we present artificial confocal microscopy (ACM) to achieve confocal-level depth sectioning, sensitivity, and chemical specificity, on unlabeled specimens, nondestructively. We equipped a commercial laser scanning confocal instrument with a quantitative phase imaging module, which provides optical path-length maps of the specimen in the same field of view as the fluorescence channel. Using pairs of phase and fluorescence images, we trained a convolution neural network to translate the former into the latter. The training to infer a new tag is very practical as the input and ground truth data are intrinsically registered, and the data acquisition is automated. The ACM images present significantly stronger depth sectioning than the input (phase) images, enabling us to recover confocal-like tomographic volumes of microspheres, hippocampal neurons in culture, and 3D liver cancer spheroids. By training on nucleus-specific tags, ACM allows for segmenting individual nuclei within dense spheroids for both cell counting and volume measurements. In summary, ACM can provide quantitative, dynamic data, nondestructively from thick samples, while chemical specificity is recovered computationally.

7.
Clin Immunol ; 247: 109239, 2023 02.
Article in English | MEDLINE | ID: mdl-36682593

ABSTRACT

T-helper cytokines interferon gamma (IFNÉ£), interleukin 17 (IL-17) and IL-10 impact systemic lupus erythematosus (SLE) directly and indirectly via modulation of autoAb production. We determined the separate and combined effects on clinical manifestations of SLE (N = 62). IFNÉ£, IL-17 but not IL-10 were significantly elevated in patients with SLE. IFNÉ£ positively correlated with anti-DNA and anti-SSA. IL-17 positively correlated with anti-SSA and was significantly higher in patients with discoid rash and class V LN. IL-10 did not correlate with circulating autoantibodies but was significantly elevated in patients with LN. Patients with LN had elevated plasma levels of anti-DNA and anti-Sm/ribonuclear protein (RNP). Anti-Sm/RNP levels were decreased in patients with acute mucocutaneous manifestations, including photosensitivity and/or malar rash. The study provides critical insights into pathological mechanisms of LN, which could help guide future diagnoses and therapies.


Subject(s)
Lupus Erythematosus, Systemic , Lupus Nephritis , Humans , Cytokines , Interleukin-17 , Cross-Sectional Studies , Autoantibodies , T-Lymphocytes , Interferon-gamma , Antibodies, Antinuclear
9.
Clin Immunol ; 244: 109130, 2022 11.
Article in English | MEDLINE | ID: mdl-36189576

ABSTRACT

Here, we report a case of atopic dermatitis (AD) in a patient who received biweekly doses of dupilumab, an antibody against the IL-4 receptor α chain (IL-4Rα). Single cell RNA-sequencing showed that naïve B cells expressed the highest levels of IL4R compared to other B cell subpopulations. Compared to controls, the dupilumab-treated patient exhibited diminished percentages of IL4R+IGHD+ naïve B cells and down-regulation of IL4R, FCER2 (CD23), and IGHD. Dupilumab treatment resulted in upregulation of genes associated with apoptosis and inhibition of B cell receptor signaling and down-regulation of class-switch and memory B cell development genes. The dupilumab-treated patient exhibited a rapid decline in COVID-19 anti-spike and anti-receptor binding domain antibodies between 4 and 8 and 11 months post COVID-19 vaccination. Our data suggest that intact and persistent IL-4 signaling is necessary for maintaining robust survival and development of naïve B cells, and maintaining a long term vaccine response.


Subject(s)
COVID-19 Drug Treatment , Receptors, Interleukin-4 , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , COVID-19 Vaccines , Humans , Interleukin-4 , RNA , Receptors, Antigen, B-Cell
10.
Tissue Eng Part B Rev ; 28(6): 1209-1222, 2022 12.
Article in English | MEDLINE | ID: mdl-35451330

ABSTRACT

Organoids, which are multicellular clusters with similar physiological functions to living organs, have gained increasing attention in bioengineering. As organoids become more advanced, methods to form complex structures continue to develop. There is evidence that the extracellular microenvironment can regulate organoid quality. The extracellular microenvironment consists of soluble bioactive molecules, extracellular matrix, and biofluid flow. However, few efforts have been made to discuss the microenvironment optimal to engineer specific organoids. Therefore, this review article examines the extent to which engineered extracellular microenvironments regulate organoid quality. First, we summarize the natural tissue and organ's unique chemical and mechanical properties, guiding researchers to design an extracellular microenvironment used for organoid engineering. Then, we summarize how the microenvironments contribute to the formation and growth of the brain, lung, intestine, liver, retinal, and kidney organoids. The approaches to forming and evaluating the resulting organoids are also discussed in detail. Impact statement Organoids, which are multicellular clusters with similar physiological function to living organs, have been gaining increasing attention in bioengineering. As organoids become more advanced, methods to form complex structures continue to develop. This review article focuses on recent efforts to engineer the extracellular microenvironment in organoid research. We summarized the natural organ's microenvironment, which informs researchers of key factors that can influence organoid formation. Then, we summarize how these microenvironmental controls significantly contribute to the formation and growth of the corresponding brain, lung, intestine, liver, retinal, and kidney organoids. The approaches to forming and evaluating the resulting organoids are discussed in detail, including extracellular matrix choice and properties, culture methods, and the evaluation of the morphology and functionality through imaging and biochemical analysis.


Subject(s)
Extracellular Matrix , Organoids , Humans , Organoids/physiology , Extracellular Matrix/chemistry , Bioengineering/methods , Liver
11.
Int J Infect Dis ; 117: 222-229, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35121126

ABSTRACT

OBJECTIVES: We aimed to determine if offering a 12-dose once-weekly treatment (3HP) as an additional treatment option would result in an increase in the overall proportion of patients completing TB preventive treatment (TPT) above the baseline rate. METHODS: We analyzed outcomes in consecutive adults referred to a TB clinic from January 2010 to May 2019. Starting December 2016, 3HP was offered as an alternative to standard clinic regimens which included 9 months of daily isoniazid or 4 months of daily rifampin. The primary outcome was the proportion of patients who completed TPT among all patients who started treatment. Using segmented autoregression analysis, we compared completion at the end of the study with projected completion had the intervention not been introduced. RESULTS: A total of 2803 adults were referred for assessment over the study period. There was an absolute increase in completions among those who started a treatment of 19.0% at the end of the study between the observed intervention completion rate and the projected completion rate from the baseline study period (the completion rate had the 3HP intervention not been introduced) (76% observed vs 57% projected; 95% CI 6.6 to 31.4%; p = 0.004) and an absolute increase among those who were offered treatment (17.3%; 95% CI, 2.3 to 32.3%; p = 0.025). CONCLUSIONS: The introduction of 3HP for TPT as an alternative to the regular regimens offered resulted in a significant increase in the proportion of patients completing treatment. Our study provides evidence to support accelerated use of 3HP in Canada.


Subject(s)
Antitubercular Agents , Latent Tuberculosis , Adult , Antitubercular Agents/therapeutic use , Drug Therapy, Combination , Humans , Interrupted Time Series Analysis , Isoniazid/therapeutic use , Latent Tuberculosis/drug therapy , Rifampin/therapeutic use
12.
Clin Infect Dis ; 72(12): 2187-2195, 2021 06 15.
Article in English | MEDLINE | ID: mdl-32293676

ABSTRACT

BACKGROUND: In the last decade, tuberculosis (TB) incidence among Inuit in the Canadian Arctic has been rising. Our aim was to better understand the transmission dynamics of TB in this remote region of Canada using whole-genome sequencing. METHODS: Isolates from patients who had culture-positive pulmonary TB in Iqaluit, Nunavut, between 2009 and 2015 underwent whole-genome sequencing (WGS). The number of transmission events between cases within clusters was calculated using a threshold of a ≤3 single nucleotide polymorphism (SNP) difference between isolates and then combined with detailed epidemiological data using a reproducible novel algorithm. Social network analysis of epidemiological data was used to support the WGS data analysis. RESULTS: During the study period, 140 Mycobacterium tuberculosis isolates from 135 cases were sequenced. Four clusters were identified, all from Euro-American lineage. One cluster represented 62% of all cases that were sequenced over the entire study period. In this cluster, 2 large chains of transmission were associated with 3 superspreading events in a homeless shelter. One of the superspreading events was linked to a nonsanctioned gambling house that resulted in further transmission. Shelter to nonshelter transmission was also confirmed. An algorithm developed for the determination of transmission events demonstrated very good reproducibility (κ score .98, 95% confidence interval, .97-1.0). CONCLUSIONS: Our study suggests that socioeconomic factors, namely residing in a homeless shelter and spending time in a gambling house, combined with the superspreading event effect may have been significant factors explaining the rise in cases in this predominantly Inuit Arctic community.


Subject(s)
Mycobacterium tuberculosis , Canada/epidemiology , Genome, Bacterial , Humans , Inuit , Molecular Epidemiology , Mycobacterium tuberculosis/genetics , Nunavut/epidemiology , Polymorphism, Single Nucleotide , Reproducibility of Results
14.
Menopause ; 28(4): 439-443, 2020 12 14.
Article in English | MEDLINE | ID: mdl-33323762

ABSTRACT

OBJECTIVE: Dysregulated responses to experimental stress paradigms may indicate exposure to chronic stress. Vasomotor symptoms (VMS) are linked with diminished quality of life and psychological stress, but induced stress responsivity has received limited investigation. We examined whether women with and without VMS differ in their evoked hypothalamic-pituitary-adrenal axis, subjective, hemodynamic, and thermal stress responses. METHODS: A total of 37 midlife women (27 VMS+; 10 VMS-) completed 2 experimental stress paradigms: (1) Montreal Imaging Stress Task (MIST; computerized social-evaluative stressor) and (2) Quantitative Sensory Testing (QST; thermal stress task). Responses on a five-domain (range 0-50) Visual Analog Scale, salivary cortisol (hypothalamic-pituitary-adrenal axis), and hemodynamic indices (blood pressure, heart rate) were measured before and after each task to compare within-person change between groups. Thermal sensitivity was assessed on the QST. RESULTS: On the MIST, the VMS+ group showed a smaller cortisol release (0.01 vs 0.07 µg/dL; P = 0.046; corresponding to 54% vs 83% increases), and subjective stress response (21.2- vs 31.1-point Visual Analog Scale increase, P = 0.05; corresponding to 2427% vs 2863% increases) but no hemodynamic difference, compared to the VMS- group. The QST did not provoke stress responses via cortisol release or subjective report, but the VMS+ group tended to perceive heat at a higher temperature (38.5°C vs 36.4°C, P = 0.08). CONCLUSIONS: Women with VMS exhibited both diminished cortisol and subjective stress responses to the MIST, and reduced thermal sensitivity on QST compared to women without VMS. Dysregulated stress responsivity provides preliminary evidence suggesting that VMS may represent a chronic stress condition.


Subject(s)
Hypothalamo-Hypophyseal System , Quality of Life , Female , Humans , Hydrocortisone , Pituitary-Adrenal System , Saliva , Stress, Psychological
15.
Nat Commun ; 11(1): 6256, 2020 12 07.
Article in English | MEDLINE | ID: mdl-33288761

ABSTRACT

Due to its specificity, fluorescence microscopy has become a quintessential imaging tool in cell biology. However, photobleaching, phototoxicity, and related artifacts continue to limit fluorescence microscopy's utility. Recently, it has been shown that artificial intelligence (AI) can transform one form of contrast into another. We present phase imaging with computational specificity (PICS), a combination of quantitative phase imaging and AI, which provides information about unlabeled live cells with high specificity. Our imaging system allows for automatic training, while inference is built into the acquisition software and runs in real-time. Applying the computed fluorescence maps back to the quantitative phase imaging (QPI) data, we measured the growth of both nuclei and cytoplasm independently, over many days, without loss of viability. Using a QPI method that suppresses multiple scattering, we measured the dry mass content of individual cell nuclei within spheroids. In its current implementation, PICS offers a versatile quantitative technique for continuous simultaneous monitoring of individual cellular components in biological applications where long-term label-free imaging is desirable.


Subject(s)
Artificial Intelligence , Cell Nucleus/metabolism , Cytoplasm/metabolism , Microscopy, Fluorescence/methods , Time-Lapse Imaging/methods , Algorithms , Animals , CHO Cells , Cell Compartmentation , Cell Line, Tumor , Cricetinae , Cricetulus , Hep G2 Cells , Humans , Intracellular Space/metabolism , Microscopy, Interference/methods , Microscopy, Phase-Contrast/methods , Reproducibility of Results
16.
Environ Sci Technol ; 54(21): 13797-13806, 2020 11 03.
Article in English | MEDLINE | ID: mdl-32975940

ABSTRACT

Endocrine disrupting chemicals (EDC) include synthetic compounds that mimic the structure or function of natural hormones. While most studies utilize live embryos or primary cells from adult fish, these cells rapidly lose functionality when cultured on plastic or glass substrates coated with extracellular matrix proteins. This study hypothesizes that the softness of a matrix with adhered fish cells can regulate the intercellular organization and physiological function of engineered hepatoids during EDC exposure. We scrutinized this hypothesis by culturing zebrafish hepatocytes (ZF-L) on collagen-based hydrogels with controlled elastic moduli by examining morphology, urea production, and intracellular oxidative stress of hepatoids exposed to 17ß-estradiol. Interestingly, the softer gel drove cells to form a cell sheet with a canaliculi-like structure compared to its stiffer gel counterpart. The hepatoids cultured on the softer gel exhibited more active urea production upon exposure to 17ß-estradiol and displayed faster recovery of intracellular reactive oxygen species level confirmed by gradient light interference microscopy (GLIM), a live-cell imaging technique. These results are broadly useful to improve screening and understanding of potential EDC impacts on aquatic organisms and human health.


Subject(s)
Endocrine Disruptors , Water Pollutants, Chemical , Animals , Endocrine Disruptors/toxicity , Estradiol/pharmacology , Hepatocytes , Humans , Reactive Oxygen Species/pharmacology , Water Pollutants, Chemical/pharmacology , Zebrafish
17.
Curr Allergy Asthma Rep ; 20(2): 5, 2020 02 06.
Article in English | MEDLINE | ID: mdl-32030507

ABSTRACT

PURPOSE OF REVIEW: Using the WHO Conceptual Framework for Action on the Social Determinants of Health, this review provides a discussion of recent epidemiologic, mechanistic, and intervention studies of structural and social determinants of health and asthma outcomes covering the period from 2014 to 2019. RECENT FINDINGS: A majority of studies and interventions to date focus on the intermediary determinants of health (e.g., housing), which as the name suggests, exist between the patient and the upstream structural determinants of health (e.g., housing policy). Race/ethnicity remains a profound social driver of asthma disparities with cumulative risk from many overlapping determinants. A growing number of studies on asthma are beginning to elucidate the underlying mechanisms that connect social determinants to human disease. Several effective interventions have been developed, though a need for large-scale policy research and innovation remains. Strong evidence supports the key role of the structural determinants, which generate social stratification and inequity, in the development and progression of asthma; yet, interventions in this realm are challenging to develop and therefore infrequent. Proximal, intermediary determinants have provided a natural starting point for interventions, though structural interventions have the most potential for major impact on asthma outcomes. Further research to investigate the interactive effect of multiple determinants, as well as intervention studies, specifically those that are cross-sector and propose innovative strategies to target structural determinants, are needed to address asthma morbidities, and more importantly, close the asthma disparity gap.


Subject(s)
Asthma/epidemiology , Developed Countries/economics , Social Determinants of Health/economics , Ethnicity , Health Status Disparities , Housing , Humans , World Health Organization
18.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Article in English | MEDLINE | ID: mdl-31693131

ABSTRACT

CONTEXT: Women are at increased risk for depressive symptoms during the menopause transition. Changes in estradiol secretion and presence of vasomotor symptoms (VMS) contribute to perimenopausal depressive symptoms, but links with progesterone have not been investigated. OBJECTIVE: To determine whether estradiol variability, ovulatory levels of progesterone, and VMS burden are independently associated with perimenopausal depressive symptomatology. DESIGN AND INTERVENTION: Depressive symptoms, serum levels of estradiol and progesterone, and VMS frequency were assessed weekly in an 8-week observational study. Association of mood with estradiol variability, ovulatory levels of progesterone, and VMS frequency were estimated using generalized estimating equation models. SETTING: Academic medical center. PATIENTS: Fifty unmedicated perimenopausal women with mild-to-moderate depressive symptoms (mean Montgomery-Åsberg Depression Rating Scale [MADRS] score 15.5 ± 5.3). MAIN OUTCOME MEASURE: Depressive symptoms (MADRS score). RESULTS: During the study, 90.0% of participants had varying estradiol levels, 51.1% had ovulatory progesterone levels, and 90% had VMS. Greater estradiol variability and absence of progesterone levels consistent with ovulation, but not VMS frequency, are associated with higher levels of depressive symptoms (ß = 0.11 [95% confidence interval (95% CI), 0.04 to 0.18; P = 0.001]; ß = -2.62 [95% CI, -4.52 to -0.71; P = 0.007], respectively), after accounting for higher body mass index, lifetime history of depression, and stressful life events. CONCLUSIONS: Increasing dysregulation of ovarian hormones, but not VMS, associates with more depressive symptom burden during perimenopause. These results suggest that perimenopausal mood instability is driven by the underlying hormonal dysregulation of the menopause transition involving changes in both estradiol and progesterone.


Subject(s)
Depression/etiology , Estradiol/blood , Perimenopause/blood , Perimenopause/psychology , Progesterone/blood , Adult , Affect , Depression/epidemiology , Female , Hot Flashes , Humans , Middle Aged , Ovulation/blood , Vasomotor System
19.
Nat Commun ; 10(1): 4691, 2019 10 16.
Article in English | MEDLINE | ID: mdl-31619681

ABSTRACT

Multiple scattering and absorption limit the depth at which biological tissues can be imaged with light. In thick unlabeled specimens, multiple scattering randomizes the phase of the field and absorption attenuates light that travels long optical paths. These obstacles limit the performance of transmission imaging. To mitigate these challenges, we developed an epi-illumination gradient light interference microscope (epi-GLIM) as a label-free phase imaging modality applicable to bulk or opaque samples. Epi-GLIM enables studying turbid structures that are hundreds of microns thick and otherwise opaque to transmitted light. We demonstrate this approach with a variety of man-made and biological samples that are incompatible with imaging in a transmission geometry: semiconductors wafers, specimens on opaque and birefringent substrates, cells in microplates, and bulk tissues. We demonstrate that the epi-GLIM data can be used to solve the inverse scattering problem and reconstruct the tomography of single cells and model organisms.


Subject(s)
Microscopy, Interference/instrumentation , Animals , Brain , HeLa Cells , Hep G2 Cells , Humans , Imaging, Three-Dimensional , Larva , Mice , Microscopy, Interference/methods , Neurons , Optical Imaging , Quartz , Rats , Semiconductors , Tendons , Zebrafish
20.
Sch Psychol ; 34(2): 222-232, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30589313

ABSTRACT

Middle school is a risky period, marked by increased peer victimization, and the onset of several mental disorders, including suicidal thoughts and behaviors (STBs). Parental involvement is critical to students' well-being; however, few studies have examined the role of parental involvement among middle school students or its effect on their mental health. This study examined the effects of perceived parental involvement and victimization on adolescents' mental health difficulties (MHDs) and STBs. We also investigated whether these effects varied across demographic groups, and whether perceived parental involvement buffers the relationship between victimization and students' mental health outcomes. The sample consisted of 301,628 students (50.7% female) from 615 middle schools (Grades 6 to 8) in Georgia (United States). Hierarchical linear modeling showed that higher student-level perceived parental involvement was related to fewer MHDs (b = -0.20) and STBs (b = -0.10), and higher school-level perceived parental involvement was related to fewer STBs (b = -0.11). However, higher student-level (b = 0.25, 0.08) and school-level (b = 0.37, 0.10) traditional victimization were associated with more MHDs and STBs. Student-level perceived parental involvement was also more positively related to MHDs and STBs for 6th (b = 0.06, 0.04) and 7th graders (b = 0.03, 0.02) than for 8th graders, and it was more negatively related to MHDs (b = -0.24) and STBs (b = -0.13) for girls than for boys. Perceived parental involvement also moderated the relationships among traditional victimization, cyber victimization MHDs, and STBs. Implications are discussed relating to how schools can promote parental involvement and student mental health. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Subject(s)
Adolescent Behavior/psychology , Behavioral Symptoms/psychology , Bullying/psychology , Crime Victims/psychology , Parent-Child Relations , Parenting/psychology , Students/psychology , Suicide/psychology , Adolescent , Female , Humans , Male , Schools , Suicidal Ideation
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