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1.
Curr Biol ; 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39067449

ABSTRACT

Selfish genetic elements drive in meiosis to distort their transmission ratio and increase their representation in gametes, violating Mendel's law of segregation. The two established paradigms for meiotic drive, gamete killing and biased segregation, are fundamentally different. In gamete killing, typically observed with male meiosis, selfish elements sabotage gametes that do not contain them. By contrast, killing is predetermined in female meiosis, and selfish elements bias their segregation to the single surviving gamete (i.e., the egg in animal meiosis). Here, we show that a selfish element on mouse chromosome 2, Responder to drive 2 (R2d2), drives using a hybrid mechanism in female meiosis, incorporating elements of both killing and biased segregation. We propose that if R2d2 is destined for the polar body, it manipulates segregation to sabotage the egg by causing aneuploidy, which is subsequently lethal in the embryo, ensuring that surviving progeny preferentially contain R2d2. In heterozygous females, R2d2 orients randomly on the metaphase spindle but lags during anaphase and preferentially remains in the egg, regardless of its initial orientation. Thus, the egg genotype is either euploid with R2d2 or aneuploid with both homologs of chromosome 2, with only the former generating viable embryos. Consistent with this model, R2d2 heterozygous females produce eggs with increased aneuploidy for chromosome 2, increased embryonic lethality, and increased transmission of R2d2. In contrast to typical gamete killing of sisters produced as daughter cells in a single meiosis, R2d2 prevents production of any viable gametes from meiotic divisions in which it should have been excluded from the egg.

2.
bioRxiv ; 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38903120

ABSTRACT

During meiosis, homologous chromosomes segregate so that alleles are transmitted equally to haploid gametes, following Mendel's Law of Segregation. However, some selfish genetic elements drive in meiosis to distort the transmission ratio and increase their representation in gametes. The established paradigms for drive are fundamentally different for female vs male meiosis. In male meiosis, selfish elements typically kill gametes that do not contain them. In female meiosis, killing is predetermined, and selfish elements bias their segregation to the single surviving gamete (i.e., the egg in animal meiosis). Here we show that a selfish element on mouse chromosome 2, R2d2, drives using a hybrid mechanism in female meiosis, incorporating elements of both male and female drivers. If R2d2 is destined for the polar body, it manipulates segregation to sabotage the egg by causing aneuploidy that is subsequently lethal in the embryo, so that surviving progeny preferentially contain R2d2. In heterozygous females, R2d2 orients randomly on the metaphase spindle but lags during anaphase and preferentially remains in the egg, regardless of its initial orientation. Thus, the egg genotype is either euploid with R2d2 or aneuploid with both homologs of chromosome 2, with only the former generating viable embryos. Consistent with this model, R2d2 heterozygous females produce eggs with increased aneuploidy for chromosome 2, increased embryonic lethality, and increased transmission of R2d2. In contrast to a male meiotic driver, which kills its sister gametes produced as daughter cells in the same meiosis, R2d2 eliminates "cousins" produced from meioses in which it should have been excluded from the egg.

3.
Nanoscale Adv ; 4(24): 5343-5354, 2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36540114

ABSTRACT

Titanium dioxide, or titania, is perhaps the most well-known and widely studied photocatalytic material, with myriad applications, due to a high degree of tunability achievable through the incorporation of dopants and control of phase composition and particle size. Many of the applications of titanium dioxide require particular forms, such as gels, coatings, or thin films, making the development of hybrid solution processable nanoparticles increasingly attractive. Here we report a simple solvothermal route to highly dispersible anatase phase titanium dioxide hybrid nanoparticles from amorphous titania. Solvothermal treatment of the amorphous titania in trifluoroacetic acid leads to the formation of anatase phase nanoparticles with a high degree of size control and near complete surface functionalisation. This renders the particles highly dispersible in simple organic solvents such as acetone. Dopant ions may be readily incorporated into the amorphous precursor by co-precipitation, with no adverse effect on subsequent crystallisation and surface modification.

4.
Environ Microbiol ; 24(12): 6112-6127, 2022 12.
Article in English | MEDLINE | ID: mdl-36222141

ABSTRACT

Saline springs within the Illinois Basin result from the discharge of deep-seated evaporated seawater (brine) and likely contain diverse and complex microbial communities that are poorly understood. In this study, seven saline/mineral springs with different geochemical characteristics and salinity origins were investigated using geochemical and molecular microbiological analyses to reveal the composition of microbial communities inhabiting springs and their key controlling factors. The 16S rRNA sequencing results demonstrated that each spring harbours a unique microbial community influenced by its geochemical properties and subsurface conditions. The microbial communities in springs that originated from Cambrian/Ordovician strata, which are deep confined units that have limited recharge from overlying formations, share a greater similarity in community composition and have a higher species richness and more overlapped taxa than those that originated from shallower Pennsylvanian strata, which are subject to extensive regional surface and groundwater recharge. The microbial distribution along the spring flow paths at the surface indicates that 59.8%-94.2% of total sequences in sedimentary samples originated from spring water, highlighting the role of springs in influencing microbiota in the immediate terrestrial environment. The results indicate that the springs introduce microbiota with a high biodiversity into surface terrestrial or aquatic ecosystems, potentially affecting microbial reservoirs in downstream ecosystems.


Subject(s)
Groundwater , Microbiota , RNA, Ribosomal, 16S/genetics , Salinity , Microbiota/genetics , Groundwater/microbiology , Seawater/microbiology
5.
FASEB J ; 36(2): e22155, 2022 02.
Article in English | MEDLINE | ID: mdl-35044708

ABSTRACT

The extracellular matrix (ECM) in skeletal muscle plays an integral role in tissue development, structural support, and force transmission. For successful adaptation to mechanical loading, remodeling processes must occur. In a large cohort of older adults, transcriptomics revealed that genes involved in ECM remodeling, including matrix metalloproteinase 14 (MMP14), were the most upregulated following 14 weeks of progressive resistance exercise training (PRT). Using single-cell RNA-seq, we identified macrophages as a source of Mmp14 in muscle following a hypertrophic exercise stimulus in mice. In vitro contractile activity in myotubes revealed that the gene encoding cytokine leukemia inhibitory factor (LIF) is robustly upregulated and can stimulate Mmp14 expression in macrophages. Functional experiments confirmed that modulation of this muscle cell-macrophage axis facilitated Type I collagen turnover. Finally, changes in LIF expression were significantly correlated with MMP14 expression in humans following 14 weeks of PRT. Our experiments reveal a mechanism whereby muscle fibers influence macrophage behavior to promote ECM remodeling in response to mechanical loading.


Subject(s)
Extracellular Matrix/metabolism , Leukocytes, Mononuclear/metabolism , Matrix Metalloproteinase 14/metabolism , Muscle Fibers, Skeletal/metabolism , Adult , Aged , Animals , Cells, Cultured , Collagen Type I/metabolism , Female , Humans , Leukemia Inhibitory Factor/metabolism , Macrophages/metabolism , Male , Mice , Muscle Contraction/physiology , Muscle, Skeletal/metabolism , Resistance Training/methods
6.
FASEB J ; 35(6): e21644, 2021 06.
Article in English | MEDLINE | ID: mdl-34033143

ABSTRACT

How regular physical activity is able to improve health remains poorly understood. The release of factors from skeletal muscle following exercise has been proposed as a possible mechanism mediating such systemic benefits. We describe a mechanism wherein skeletal muscle, in response to a hypertrophic stimulus induced by mechanical overload (MOV), released extracellular vesicles (EVs) containing muscle-specific miR-1 that were preferentially taken up by epidydimal white adipose tissue (eWAT). In eWAT, miR-1 promoted adrenergic signaling and lipolysis by targeting Tfap2α, a known repressor of Adrß3 expression. Inhibiting EV release prevented the MOV-induced increase in eWAT miR-1 abundance and expression of lipolytic genes. Resistance exercise decreased skeletal muscle miR-1 expression with a concomitant increase in plasma EV miR-1 abundance, suggesting a similar mechanism may be operative in humans. Altogether, these findings demonstrate that skeletal muscle promotes metabolic adaptations in adipose tissue in response to MOV via EV-mediated delivery of miR-1.


Subject(s)
Adipose Tissue, White/physiopathology , Exercise , Extracellular Vesicles/physiology , Lipolysis , MicroRNAs/genetics , Muscle, Skeletal/physiopathology , Stress, Mechanical , Transcription Factor AP-2/metabolism , Adolescent , Adult , Animals , Female , Gene Expression Regulation , Humans , Male , Mice , Mice, Inbred C57BL , Middle Aged , Transcription Factor AP-2/genetics , Young Adult
7.
Physiol Genomics ; 53(5): 206-221, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33870722

ABSTRACT

The skeletal muscle hypertrophic response to resistance exercise training (RT) is highly variable across individuals. The molecular underpinnings of this heterogeneity are unclear. This study investigated transcriptional networks linked to RT-induced muscle hypertrophy, classified as 1) predictive of hypertrophy, 2) responsive to RT independent of muscle hypertrophy, or 3) plastic with hypertrophy. Older adults (n = 31, 18 F/13 M, 70 ± 4 yr) underwent 14-wk RT (3 days/wk, alternating high-low-high intensity). Muscle hypertrophy was assessed by pre- to post-RT change in mid-thigh muscle cross-sectional area (CSA) [computed tomography (CT), primary outcome] and thigh lean mass [dual-energy X-ray absorptiometry (DXA), secondary outcome]. Transcriptome-wide poly-A RNA-seq was performed on vastus lateralis tissue collected pre- (n = 31) and post-RT (n = 22). Prediction networks (using only baseline RNA-seq) were identified by weighted gene correlation network analysis (WGCNA). To identify Plasticity networks, WGCNA change indices for paired samples were calculated and correlated to changes in muscle size outcomes. Pathway-level information extractor (PLIER) was applied to identify Response networks and link genes to biological annotation. Prediction networks (n = 6) confirmed transcripts previously connected to resistance/aerobic training adaptations in the MetaMEx database while revealing novel member genes that should fuel future research to understand the influence of baseline muscle gene expression on hypertrophy. Response networks (n = 6) indicated RT-induced increase in aerobic metabolism and reduced expression of genes associated with spliceosome biology and type-I myofibers. A single exploratory Plasticity network was identified. Findings support that interindividual differences in baseline gene expression may contribute more than RT-induced changes in gene networks to muscle hypertrophic response heterogeneity. Code/Data: https://github.com/kallavin/MASTERS_manuscript/tree/master.


Subject(s)
Gene Regulatory Networks , Resistance Training , Skeletal Muscle Enlargement/genetics , Absorptiometry, Photon , Aged , Female , Humans , Male , Muscle, Skeletal/physiology
8.
Sci Rep ; 11(1): 9266, 2021 04 29.
Article in English | MEDLINE | ID: mdl-33927217

ABSTRACT

Modifications of the myocardial architecture can cause abnormal electrical activity of the heart. Fibro-fatty infiltrations have been implicated in various cardiac pathologies associated with arrhythmias and sudden cardiac death, such as arrhythmogenic right ventricular cardiomyopathy (ARVC). Here, we report the development of an MRI protocol to observe these modifications at 9.4 T. Two fixed ex vivo human hearts, one healthy and one ARVC, were imaged with an Iterative decomposition with echo asymmetry and least-square estimations (IDEAL) and a magnetization transfer (MT) 3D sequences. The resulting fat fraction and MT ratio (MTR) were analyzed and compared to histological analysis of the three regions ("ARVC triangle") primarily involved in ARVC structural remodeling. In the ARVC heart, high fat content was observed in the "ARVC triangle" and the superimposition of the MTR and fat fraction allowed the identification of fibrotic regions in areas without the presence of fat. The healthy heart exhibited twice less fat than the ARVC heart (31.9%, 28.7% and 1.3% of fat in the same regions, respectively). Localization of fat and fibrosis were confirmed by means of histology. This non-destructive approach allows the investigation of structural remodeling in human pathologies where fibrosis and/or fatty tissue infiltrations are expected to occur.


Subject(s)
Adipose Tissue/diagnostic imaging , Arrhythmogenic Right Ventricular Dysplasia/diagnostic imaging , Heart/diagnostic imaging , Adipose Tissue/pathology , Adult , Arrhythmogenic Right Ventricular Dysplasia/pathology , Fibrosis , Humans , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Male
9.
Curr Oncol ; 27(5): e459-e466, 2020 10.
Article in English | MEDLINE | ID: mdl-33173385

ABSTRACT

Methods: A retrospective cohort study considered patients 18 or more years of age diagnosed between January 2007 and May 2018 with unresectable stage iii non-small-cell lung cancer (nsclc) who received combined chemoradiation (crt). Survival was analyzed using the Kaplan-Meier method to determine median overall (os) and progression-free survival (pfs) and the associated 95% confidence intervals (cis). Cox regression analysis was performed to identify factors prognostic for survival, including age, sex, smoking status, Eastern Cooperative Oncology Group performance status (ecog ps), histology, treatment type, tumour size, and nodal status. Results: Of 226 patients diagnosed with unresectable stage iii disease, 134 (59%) received combined crt. Mean age was 63 years; most patients were white, were current smokers, had an ecog ps of 0 or 1, and had nonsquamous histology. Median pfs was 7.03 months (95% ci: 5.6 months to 8.5 months), and os for the cohort was 18.7 months (95% ci: 12.4 months to 24.8 months). Of those patients, 78% would have been eligible for durvalumab consolidation therapy. Univariate analysis demonstrated a significant os benefit (p = 0.010) for concurrent crt (ccrt) compared with sequential crt (scrt). Disease-specific survival remained significantly better in the ccrt group (p = 0.004). No difference in pfs was found between the ccrt and scrt groups. In addition, tumour size and nodal involvement were significant discriminating factors for survival (p < 0.05). In this patient cohort, 64% of patients progressed and received subsequent therapy. Based on multivariate analysis, tumour size and nodal station were the only factors predictive of survival in patients with unresectable stage iii nsclc treated with crt. Conclusions: Combined crt has been the standard treatment for unresectable stage iii nsclc. In our study, a trend of better survival was seen for ccrt compared with scrt. Factors predictive of survival in patients with stage iii disease treated with crt were tumour size and nodal station. Most patients with stage iii disease would potentially be eligible for durvalumab maintenance therapy based on the eligibility criteria from the pacific trial. The use and effectiveness of novel treatments will have to be further studied in our real-world patient population and similar populations elsewhere.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/therapy , Female , Humans , Lung Neoplasms/pathology , Lung Neoplasms/therapy , Male , Middle Aged , Neoplasm Staging , Practice Patterns, Physicians' , Quebec , Retrospective Studies
10.
Aging (Albany NY) ; 12(20): 19852-19866, 2020 10 18.
Article in English | MEDLINE | ID: mdl-33071237

ABSTRACT

Evidence from clinical trials and observational studies suggests that both progressive resistance exercise training (PRT) and metformin delay a variety of age-related morbidities. Previously, we completed a clinical trial testing the effects of 14 weeks of PRT + metformin (metPRT) compared to PRT with placebo (plaPRT) on muscle hypertrophy in older adults. We found that metformin blunted PRT-induced muscle hypertrophic response. To understand potential mechanisms underlying the inhibitory effect of metformin on PRT, we analyzed the muscle transcriptome in 23 metPRT and 24 plaPRT participants. PRT significantly increased expression of genes involved in extracellular matrix remodeling pathways, and downregulated RNA processing pathways in both groups, however, metformin attenuated the number of differentially expressed genes within these pathways compared to plaPRT. Pathway analysis showed that genes unique to metPRT modulated aging-relevant pathways, such as cellular senescence and autophagy. Differentially expressed genes from baseline biopsies in older adults compared to resting muscle from young volunteers were reduced following PRT in plaPRT and were further reduced in metPRT. We suggest that although metformin may blunt pathways induced by PRT to promote muscle hypertrophy, adjunctive metformin during PRT may have beneficial effects on aging-associated pathways in muscle from older adults.


Subject(s)
Hypoglycemic Agents/therapeutic use , Metformin/therapeutic use , Quadriceps Muscle/drug effects , Resistance Training , Skeletal Muscle Enlargement/drug effects , Transcriptome/drug effects , Adaptation, Physiological , Aged , Alabama , Double-Blind Method , Female , Gene Expression Profiling , Gene Expression Regulation , Gene Regulatory Networks , Humans , Kentucky , Male , Quadriceps Muscle/growth & development , Quadriceps Muscle/metabolism , Time Factors , Treatment Outcome
11.
Curr Oncol ; 27(4): e354-e360, 2020 08.
Article in English | MEDLINE | ID: mdl-32905267

ABSTRACT

Background: The management of unresectable stage iii non-small-cell lung cancer (nsclc) is complex and best determined through multidisciplinary consultation. A longitudinal, population-level study was carried out to describe the management approach and outcomes of treatment in the real-world setting in Ontario. Methods: Individuals diagnosed with nsclc between 1 April 2010 and 31 March 2015 were identified in the Ontario Cancer Registry. Unresectable disease was defined as no surgery reported within 3 months of diagnosis. Initial treatments included radiotherapy (rt, curative or palliative), chemotherapy, targeted therapy, and chemoradiation [crt, concurrent (ccrt) or sequential (scrt)]. Survival was calculated from diagnosis with stage iii disease to death or last follow-up. Results: Of the 24,729 individuals diagnosed with nsclc, 5243 (21.2%) had stage iii disease, with most of the latter group (4542, 86.6%) having unresectable disease. Median age was 70 years, and 54.2% were men. The frequency of first-line treatment was ccrt, 22.1%; palliative rt, 21.0%; curative rt, 19.6%; no treatment, 19.6%; chemotherapy alone, 11.6%; scrt, 5.4%; and targeted therapy, 0.7%. Median overall survival (mos) was 14.2 months [95% confidence interval (ci): 13.6 months to 14.7 months], with the longest survival observed in patients who received targeted therapy (mos: 34.7 months; 95% ci: 21.4 months to 51.2 months), and the poorest, in those receiving no cancer treatment (mos: 5.9 months; 95% ci: 5.0 months to 6.4 months). The mos in patients receiving ccrt was 23.6 months (95% ci: 21.4 months to 25.6 months). Conclusions: Guideline-recommended ccrt is undertaken in only a small proportion of patients with unresectable nsclc in Ontario. The reasons for low uptake of that recommendation are only partly understood.


Subject(s)
Carcinoma, Non-Small-Cell Lung/therapy , Lung Neoplasms/therapy , Aged , Canada , Carcinoma, Non-Small-Cell Lung/pathology , Female , Humans , Lung Neoplasms/pathology , Male , Neoplasm Staging , Retrospective Studies
12.
Curr Oncol ; 27(4): e361-e367, 2020 08.
Article in English | MEDLINE | ID: mdl-32905294

ABSTRACT

Background: Almost half of all patients with non-small-cell lung cancer (nsclc) present with stage iv disease. The objective of the present study was to characterize treatment patterns and survival outcomes in patients with advanced nsclc. Methods: We conducted a longitudinal population-level study in patients diagnosed with stage iv nsclc in Ontario between 1 April 2010 and 31 March 2015, with follow-up to 31 March 2017 for overall survival and treatment sequence. Patients were stratified as nonsquamous or squamous histology. A sub-analysis was conducted for patients with nonsquamous histology who received targeted therapies, on the assumption that their tumours were EGFR mutation-positive (EGFRm+). Treatment patterns were determined, and survival was calculated from date of diagnosis to death or censoring. Results: Of 24,729 nsclc cases identified, stage iv disease was diagnosed in 49.2%, histology was nonsquamous in 10,103, and EGFRm+ was assumed in 508. Median patient age ranged from 69 to 72 years for the three cohorts. For patients with nonsquamous histology, palliative radiotherapy was the most frequently used first-line treatment (44.4%), followed by no treatment (26.7%) and chemotherapy (14.9%). In the EGFRm+ cohort, 75.6% received gefitinib as first- or second-line therapy, and almost half (47.4%) the 473 patients with squamous histology treated with first-line chemotherapy received cisplatin or carboplatin with gemcitabine. Median overall survival in the nonsquamous and squamous cohorts was 4.9 and 4.6 months respectively; it was 17.6 months for patients who were EGFRm+. Conclusions: Survival of patients with stage iv nsclc remains poor, with the exception of patients who are EGFRm+. Only 14.9% of patients received first-line chemotherapy; the mainstay of treatment was palliative radiotherapy.


Subject(s)
Carcinoma, Non-Small-Cell Lung/therapy , Lung Neoplasms/therapy , Pragmatic Clinical Trials as Topic/methods , Aged , Canada , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Female , Humans , Longitudinal Studies , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Retrospective Studies , Survival Analysis
13.
J Am Heart Assoc ; 9(10): e015929, 2020 05 18.
Article in English | MEDLINE | ID: mdl-32390569

ABSTRACT

Background Peripheral artery disease (PAD) is a manifestation of atherosclerosis characterized by reduced blood flow to the lower extremities and mobility loss. Preliminary evidence suggests PAD damages skeletal muscle, resulting in muscle impairments that contribute to functional decline. We sought to determine whether PAD is associated with an altered macrophage profile in gastrocnemius muscles and whether muscle macrophage populations are associated with impaired muscle phenotype and walking performance in patients with PAD. Methods and Results Macrophages, satellite cells, and extracellular matrix in gastrocnemius muscles from 25 patients with PAD and 7 patients without PAD were quantified using immunohistochemistry. Among patients with PAD, both the absolute number and percentage of cluster of differentiation (CD) 11b+CD206+ M2-like macrophages positively correlated to satellite cell number (r=0.461 [P=0.023] and r=0.416 [P=0.042], respectively) but not capillary density or extracellular matrix. The number of CD11b+CD206- macrophages negatively correlated to 4-meter walk tests at normal (r=-0.447, P=0.036) and fast pace (r=-0.510, P=0.014). Extracellular matrix occupied more muscle area in PAD compared with non-PAD (8.72±2.19% versus 5.30±1.03%, P<0.001) and positively correlated with capillary density (r=0.656, P<0.001). Conclusions Among people with PAD, higher CD206+ M2-like macrophage abundance was associated with greater satellite cell numbers and muscle fiber size. Lower CD206- macrophage abundance was associated with better walking performance. Further study is needed to determine whether CD206+ macrophages are associated with ongoing reparative processes enabling skeletal muscle adaptation to damage with PAD. Registration URL: https://www.clini​caltr​ials.gov; Unique identifiers: NCT00693940, NCT01408901, NCT0224660.


Subject(s)
Macrophages/pathology , Muscle, Skeletal/pathology , Peripheral Arterial Disease/pathology , Walking , Adaptation, Physiological , Aged , Biomarkers/analysis , CD11b Antigen/analysis , Case-Control Studies , Cross-Sectional Studies , Extracellular Matrix/pathology , Female , Humans , Macrophages/immunology , Male , Membrane Glycoproteins/analysis , Microvascular Density , Middle Aged , Muscle, Skeletal/physiopathology , Observational Studies as Topic , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/physiopathology , Phenotype , Randomized Controlled Trials as Topic , Receptors, Immunologic/analysis , Satellite Cells, Skeletal Muscle/pathology
14.
FASEB J ; 34(5): 7018-7035, 2020 05.
Article in English | MEDLINE | ID: mdl-32246795

ABSTRACT

Over the past 20 years, various identifiers of cellular senescence have been used to quantify the abundance of these cells in different tissues. These include classic markers such as p16, senescence-associated ß-gal, and γH2AX, in addition to more recent markers (Sudan Black B and HMGB1). In vivo data on the usefulness of these markers in skeletal muscle are very limited and inconsistent. In the present study, we attempted to identify senescent cells in frozen human skeletal muscle biopsies using these markers to determine the effects of age and obesity on senescent cell burden; however, we were only able to assess the abundance of DNA-damaged nuclei using γH2AX immunohistochemistry. The abundance of γH2AX+ cells, including satellite cells, was not higher in muscle from old compared to young individuals; however, γH2AX+ cells were higher with obesity. Additionally, terminally differentiated, postmitotic myofiber nuclei from obese individuals had elevated γH2AX abundance compared to muscle from lean individuals. Analyses of gene expression support the conclusion that the elevated DNA damage and the senescence-associated secretory phenotype are preferentially associated with obesity in skeletal muscle. These data implicate obesity as a larger contributor to DNA damage in skeletal muscle than aging; however, more sensitive senescence markers for human skeletal muscle are needed to determine if these cells are in fact senescent.


Subject(s)
Aging/metabolism , Histones/metabolism , Muscle, Skeletal/metabolism , Obesity/metabolism , Adult , Aged , Aged, 80 and over , Aging/pathology , Biomarkers/metabolism , Cell Differentiation , Cellular Senescence , DNA Damage , DNA Repair/genetics , Female , Humans , Immunohistochemistry , Male , Muscle Fibers, Skeletal/cytology , Muscle Fibers, Skeletal/metabolism , Myoblasts, Skeletal/cytology , Myoblasts, Skeletal/metabolism , Obesity/pathology , Satellite Cells, Skeletal Muscle/cytology , Satellite Cells, Skeletal Muscle/metabolism , Young Adult
15.
Curr Oncol ; 27(1): 27-33, 2020 02.
Article in English | MEDLINE | ID: mdl-32218657

ABSTRACT

Background: Epidermal growth factor receptor (egfr) tyrosine kinase inhibitors (tkis) are standard therapy for patients with advanced or metastatic non-small-cell lung cancer harbouring an EGFR mutation. Upon progression, 50%-60% develop a secondary T790M mutation. Recent trials demonstrated outcome improvement with osimertinib compared with standard platinum-based chemotherapy as second-line therapy for patients with secondary T790M mutation. To identify T790M, a biopsy of the tumour or, more recently, plasma is necessary. This retrospective study aimed to evaluate biopsy procedures and mutational analysis at 2 Canadian cancer centres. Methods: In a retrospective review of patients who were approached to enrol in the aura2, aura3, or astris studies, demographics, eligibility for rebiopsy upon progression after an egfr tki, rebiopsy methods and complications, number of rebiopsies, and incidence of the T790M mutation were collected. Results: Of 84 patients considered for trial enrolment, 80 signed a consent. In 78 patients who underwent rebiopsy, computed tomography or ultrasonography guidance were the most common methods used. The most common biopsy sites were lung and lymph nodes. The median number of rebiopsies performed to find a T790M mutation was 2. Only 9% of patients experienced complications. Of samples obtained, 74% were adequate for testing after initial rebiopsy. A T790M mutation was found in 47 patients, of whom 44 were enrolled on a trial. After multiple rebiopsies, only 5% of samples were inadequate for molecular analysis. Conclusions: In the Canadian setting, the acceptance of rebiopsy on progression was high. Multiple rebiopsies were clinically feasible and could increase the yield for T790M mutation. The incidence of complications was low despite the most common site for rebiopsy being lung.


Subject(s)
Biopsy/methods , Carcinoma, Non-Small-Cell Lung/surgery , Lung Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Canada , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Disease Progression , ErbB Receptors/metabolism , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Middle Aged , Mutation , Retrospective Studies
16.
Am J Ophthalmol ; 213: 153-160, 2020 05.
Article in English | MEDLINE | ID: mdl-32006482

ABSTRACT

PURPOSE: To determine the ocular complications in school-age children and adolescents surviving at least 1 year following allogeneic bone marrow transplantation. DESIGN: Retrospective cohort study. METHODS: In this institutional study, 162 patients (7-18 years old) met our inclusion criteria with a mean age of 13.4 years at bone marrow transplantation. Follow-up ranged from 13 months to 12 years (mean 4 years; median 3.2 years). Patient charts were screened for cataract formation, dry eye, and other anterior and posterior segment diseases. RESULTS: Cataract formation was noted in 57 patients. Univariate analysis showed that fractionated total body irradiation, race, and use of cytarabine significantly increased the incidence of cataract formation (P < 0.05). Multivariate analysis of significant variables showed that total body irradiation was a risk factor for cataract formation. Of the 57 patients (97 eyes) who developed cataracts after bone marrow transplantation, 4 patients (6 eyes) required cataract surgery. After surgery, all patients had visual acuities of 20/20 to 20/25. Of the 162 patients, 51 developed dry eyes. Univariate analysis showed that age at transplantation; steroid use, chronic graft-versus-host disease; use of fludarabine, melphalan, and thiotepa; and receiving no pre-transplantation conditioning regimen prior to bone marrow transplant significantly increased the risk of dry eye syndrome (P < 0.05). In multivariate analysis, chronic graft-versus-host disease was a significant risk factor for dry eye syndrome. CONCLUSIONS: Due to the high incidence of cataract formation and dry eye disease in this population, this study proposes these patients be screened using examinations by a pediatric or general ophthalmologist at least every year.


Subject(s)
Bone Marrow Transplantation/adverse effects , Eye Diseases/etiology , Adolescent , Anterior Eye Segment/pathology , Cataract/diagnosis , Cataract/etiology , Child , Dry Eye Syndromes/diagnosis , Dry Eye Syndromes/etiology , Female , Follow-Up Studies , Graft vs Host Disease/etiology , Hematologic Diseases/therapy , Humans , Male , Posterior Eye Segment/pathology , Retrospective Studies , Risk Factors , Transplantation, Homologous , Visual Acuity , Whole-Body Irradiation/adverse effects
17.
Cochrane Database Syst Rev ; 12: CD011207, 2019 12 06.
Article in English | MEDLINE | ID: mdl-31808563

ABSTRACT

BACKGROUND: Community pharmacies are an easily accessible and cost-effective platform for delivering health care worldwide, and the range of services provided has undergone rapid expansion in recent years. Thus, in addition to dispensing medication, pharmacy workers within community pharmacies now give advice on a range of health-promoting behaviours that aim to improve health and to optimise the management of long-term conditions. However, it remains uncertain whether these health-promotion interventions can change the professional practice of pharmacy workers, improve health behaviours and outcomes for pharmacy users and have the potential to address health inequalities. OBJECTIVES: To assess the effectiveness and safety of health-promotion interventions to change community pharmacy workers' professional practice and improve outcomes for users of community pharmacies. SEARCH METHODS: We searched MEDLINE, Embase, CENTRAL, six other databases and two trials registers to 6 February 2018. We also conducted reference checking, citation searches and contacted study authors to identify any additional studies. SELECTION CRITERIA: We included randomised trials of health-promotion interventions in community pharmacies targeted at, or delivered by, pharmacy workers that aimed to improve the health-related behaviour of people attending the pharmacy compared to no treatment, or usual treatment received in the community pharmacy. We excluded interventions where there was no interaction between pharmacy workers and pharmacy users, and those that focused on medication use only. DATA COLLECTION AND ANALYSIS: We used standard procedures recommended by Cochrane and the Effective Practice and Organisation of Care review group for both data collection and analysis. We compared intervention to no intervention or to usual treatment using standardised mean differences (SMD) and 95% confidence intervals (95% CI) (higher scores represent better outcomes for pharmacy user health-related behaviour and quality of life, and lower scores represent better outcomes for clinical outcomes, costs and adverse events). Interpretation of effect sizes (SMD) was in line with Cochrane recommendations. MAIN RESULTS: We included 57 randomised trials with 16,220 participants, described in 83 reports. Forty-nine studies were conducted in high-income countries, and eight in middle-income countries. We found no studies that had been conducted in low-income countries. Most interventions were educational, or incorporated skills training. Interventions were directed at pharmacy workers (n = 8), pharmacy users (n = 13), or both (n = 36). The clinical areas most frequently studied were diabetes, hypertension, asthma, and modification of cardiovascular risk. Duration of follow-up of interventions was often unclear. Only five studies gave details about the theoretical basis for the intervention, and studies did not provide sufficient data to comment on health inequalities. The most common sources of bias were lack of protection against contamination - mainly in individually randomised studies - and inadequate blinding of participants. The certainty of the evidence for all outcomes was moderate. We downgraded the certainty because of the heterogeneity across studies and evidence of potential publication bias. Professional practice outcomes We conducted a narrative analysis for pharmacy worker behaviour due to high heterogeneity in the results. Health-promotion interventions probably improve pharmacy workers' behaviour (2944 participants; 9 studies; moderate-certainty evidence) when compared to no intervention. These studies typically assessed behaviour using a simulated patient (mystery shopper) methodology. Pharmacy user outcomes Health-promotion interventions probably lead to a slight improvement in health-related behaviours of pharmacy users when compared to usual treatment (SMD 0.43, 95% CI 0.14 to 0.72; I2 = 89%; 10 trials; 2138 participants; moderate-certainty evidence). These interventions probably also lead to a slight improvement in intermediate clinical outcomes, such as levels of cholesterol or glycated haemoglobin, for pharmacy users (SMD -0.43, 95% CI -0.65 to -0.21; I2 = 90%; 20 trials; 3971 participants; moderate-certainty evidence). We identified no studies that evaluated the impact of health-promotion interventions on event-based clinical outcomes, such as stroke or myocardial infarction, or the psychological well-being of pharmacy users. Health-promotion interventions probably lead to a slight improvement in quality of life for pharmacy users (SMD 0.29, 95% CI 0.08 to 0.50; I2= 82%; 10 trials, 2687 participants; moderate-certainty evidence). Adverse events No studies reported adverse events for either pharmacy workers or pharmacy users. Costs We found that health-promotion interventions are likely to be cost-effective, based on moderate-certainty evidence from five of seven studies that reported an economic evaluation. AUTHORS' CONCLUSIONS: Health-promotion interventions in the community pharmacy context probably improve pharmacy workers' behaviour and probably have a slight beneficial effect on health-related behaviour, intermediate clinical outcomes, and quality of life for pharmacy users. Such interventions are likely to be cost-effective and the effects are seen across a range of clinical conditions and health-related behaviours. Nevertheless the magnitude of the effects varies between conditions, and more effective interventions might be developed if greater consideration were given to the theoretical basis of the intervention and mechanisms for effecting behaviour change.


Subject(s)
Community Health Services , Delivery of Health Care/methods , Health Promotion , Pharmaceutical Services , Chronic Disease/therapy , Communication , Community Health Services/organization & administration , Disease Management , Health Behavior , Humans , Outcome and Process Assessment, Health Care , Pharmaceutical Services/organization & administration , Randomized Controlled Trials as Topic
18.
Sci Rep ; 9(1): 13484, 2019 09 17.
Article in English | MEDLINE | ID: mdl-31530884

ABSTRACT

Natural microbial communities consist of a limited number of abundant species and an extraordinarily diverse population of rare species referred to as the rare biosphere. Recent studies have revealed that the rare biosphere is not merely an inactive dormant population but may play substantial functional roles in the ecosystem. However, structure, activity and community assembly processes of the rare biosphere are poorly understood. In this study, we evaluated the present and living microbial community structures including rare populations in an aquifer ecosystem, the Mahomet Aquifer, USA, by both 16S rDNA and rRNA amplicon deep sequencing. The 13 groundwater samples formed three distinct groups based on the "entire" community structure, and the same grouping was obtained when focusing on the "rare" subcommunities (<0.1% of total abundance), while the "abundant" subcommunities (>1.0%) gave a different grouping. In the correlation analyses, the observed grouping pattern is associated with several geochemical factors, and structures of not only the entire community but also the rare subcommunity are correlated with geochemical profiles in the aquifer ecosystem. Our findings first indicate that the living rare biosphere in the aquifer system has the metabolic potential to adapt to local geochemical factors which dictate the community assembly processes.

19.
Aging Cell ; 18(6): e13039, 2019 12.
Article in English | MEDLINE | ID: mdl-31557380

ABSTRACT

Progressive resistance exercise training (PRT) is the most effective known intervention for combating aging skeletal muscle atrophy. However, the hypertrophic response to PRT is variable, and this may be due to muscle inflammation susceptibility. Metformin reduces inflammation, so we hypothesized that metformin would augment the muscle response to PRT in healthy women and men aged 65 and older. In a randomized, double-blind trial, participants received 1,700 mg/day metformin (N = 46) or placebo (N = 48) throughout the study, and all subjects performed 14 weeks of supervised PRT. Although responses to PRT varied, placebo gained more lean body mass (p = .003) and thigh muscle mass (p < .001) than metformin. CT scan showed that increases in thigh muscle area (p = .005) and density (p = .020) were greater in placebo versus metformin. There was a trend for blunted strength gains in metformin that did not reach statistical significance. Analyses of vastus lateralis muscle biopsies showed that metformin did not affect fiber hypertrophy, or increases in satellite cell or macrophage abundance with PRT. However, placebo had decreased type I fiber percentage while metformin did not (p = .007). Metformin led to an increase in AMPK signaling, and a trend for blunted increases in mTORC1 signaling in response to PRT. These results underscore the benefits of PRT in older adults, but metformin negatively impacts the hypertrophic response to resistance training in healthy older individuals. ClinicalTrials.gov Identifier: NCT02308228.


Subject(s)
Exercise , Hypoglycemic Agents/pharmacology , Metformin/pharmacology , Muscle Strength/drug effects , Muscle, Skeletal/drug effects , Resistance Training , Aged , Aged, 80 and over , Body Composition/drug effects , Body Weight/drug effects , Cells, Cultured , Double-Blind Method , Female , Glucose/metabolism , Humans , Male , Middle Aged , Tomography, X-Ray Computed
20.
J Vet Cardiol ; 25: 7-13, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31437785

ABSTRACT

A six-year-old Brussels griffon was presented for cervical swelling three months after implantation of a transvenous pacemaker. Transthoracic echocardiography demonstrated a thrombus associated with the pacemaker lead, partially obstructing right atrial inflow. The laboratory findings were consistent with protein-losing nephropathy. Initial medical therapy consisted of rivaroxaban (0.68 mg/kg orally every 24 hours), clopidogrel (2.5 mg/kg orally every 24 hours), and enalapril (0.5 mg/kg orally every 12 hours). Resolution of cervical and thoracic edema was noted within two weeks of initiating therapy. Recheck echocardiography two months and one year later revealed decreasing thrombus size despite worsening proteinuria. To the authors' knowledge, this is the first documented use of rivaroxaban for successful medical treatment of cranial vena cava syndrome caused by intracardiac pacemaker lead thrombosis in a hypercoagulable patient.


Subject(s)
Dog Diseases/drug therapy , Echocardiography/veterinary , Pacemaker, Artificial/veterinary , Rivaroxaban/therapeutic use , Superior Vena Cava Syndrome/veterinary , Animals , Dog Diseases/etiology , Dogs , Female , Pacemaker, Artificial/adverse effects , Superior Vena Cava Syndrome/drug therapy , Superior Vena Cava Syndrome/etiology
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