16 research outputs found
Cool, Luminous, and Highly Variable Stars in the Magellanic Clouds. II: Spectroscopic and Environmental Analysis of Thorne-\.Zytkow Object and Super-AGB Star Candidates
In previous work we identified a population of 38 cool and luminous variable
stars in the Magellanic Clouds and examined 11 in detail in order to classify
them as either Thorne-\.Zytkow Objects (T\.ZOs, red supergiants with a neutron
star cores) or super-AGB stars (the most massive stars that will not undergo
core collapse). This population includes HV\,2112, a peculiar star previously
considered in other works to be either a T\.ZO or high-mass AGB star. Here we
continue this investigation, using the kinematic and radio environments and
local star formation history of these stars to place constraints on the age of
the progenitor systems and the presence of past supernovae. These stars are not
associated with regions of recent star formation, and we find no evidence of
past supernovae at their locations. Finally, we also assess the presence of
heavy elements and lithium in their spectra compared to red supergiants. We
find strong absorption in Li and s-process elements compared to RSGs in most of
the sample, consistent with super-AGB nucleosynthesis, while HV\,2112 shows
additional strong lines associated with T\.ZO nucleosynthesis. Coupled with our
previous mass estimates, the results are consistent with the stars being
massive (~4-6.5M) or super-AGB (~6.5-12M) stars in the
thermally pulsing phase, providing crucial observations of the transition
between low- and high-mass stellar populations. HV\,2112 is more ambiguous; it
could either be a maximally massive sAGB star, or a T\.ZO if the minimum mass
for stability extends down to <13 M.Comment: 32 pages, 10 figures, 7 tables, spectroscopic data available at
https://zenodo.org/record/7058608, accepted to The Astrophysical Journa
The Distinct Metabolic Phenotype of Lung Squamous Cell Carcinoma Defines Selective Vulnerability to Glycolytic Inhibition
Adenocarcinoma (ADC) and squamous cell carcinoma (SqCC) are the two predominant subtypes of non-small cell lung cancer (NSCLC) and are distinct in their histological, molecular and clinical presentation. However, metabolic signatures specific to individual NSCLC subtypes remain unknown. Here, we perform an integrative analysis of human NSCLC tumour samples, patient-derived xenografts, murine model of NSCLC, NSCLC cell lines and The Cancer Genome Atlas (TCGA) and reveal a markedly elevated expression of the GLUT1 glucose transporter in lung SqCC, which augments glucose uptake and glycolytic flux. We show that a critical reliance on glycolysis renders lung SqCC vulnerable to glycolytic inhibition, while lung ADC exhibits significant glucose independence. Clinically, elevated GLUT1-mediated glycolysis in lung SqCC strongly correlates with high 18F-FDG uptake and poor prognosis. This previously undescribed metabolic heterogeneity of NSCLC subtypes implicates significant potential for the development of diagnostic, prognostic and targeted therapeutic strategies for lung SqCC, a cancer for which existing therapeutic options are clinically insufficient
Recurrent urinary tract infection and estrogen shape the taxonomic ecology and function of the postmenopausal urogenital microbiome
Article describes how postmenopausal women are severely affected by recurrent urinary tract infection (rUTI). The authors perform shotgun metagenomics and advanced culture on urine from a controlled cohort of postmenopausal women to identify urogenital microbiome compositional and function changes linked to rUTI susceptibility
Lung squamous cell carcinoma exhibits a targetable glucose dependency unique among non-small cell lung cancers
Cancer cells consume high amounts of glucose for their cellular bioenergetic and anabolic requirements, relying on glucose to fuel their growth. We recently reported that lung squamous cell carcinoma, a major subtype of non-small cell lung cancer (NSCLC), exhibits remarkably elevated glucose transporter GLUT1 (encoded by SLC2A1) expression and glucose dependency, while another subtype of NSCLC, lung adenocarcinoma, shows significant glucose independence. Our findings highlight the metabolic heterogeneity of glucose metabolism among lung cancer subtypes, which can be exploited for targeted lung cancer therapies
Detection of Tissue-resident Bacteria in Bladder Biopsies by 16S rRNA Fluorescence In Situ Hybridization
Urinary Glycosaminoglycans Are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women
Glycosaminoglycans (GAGs) are linear, negatively charged
polysaccharides
composed of repeating disaccharide units of uronic acid and amino
sugars. The luminal surface of the bladder epithelium is coated with
a GAG layer. These urothelial GAGs are thought to provide a protective
barrier and serve as a potential interaction site with the urinary
microbiome (urobiome). Previous studies have profiled urinary GAG
composition in mixed cohorts, but the urinary GAG composition in postmenopausal
women remains undefined. To investigate the relationship between GAGs
and recurrent urinary tract infection (rUTI), we profiled urinary
GAGs in a controlled cohort of postmenopausal women. We found that
chondroitin sulfate (CS) is the major urinary GAG in postmenopausal
women and that urinary CS was elevated in women with active rUTI.
We also associated urinary GAGs with urobiome composition and identified
bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas
somerae, and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid,
and bacterial species associated with vaginal dysbiosis were negatively
correlated with urinary CS. Altogether, this work defines changes
in urinary GAG composition associated with rUTI and identifies new
associations between urinary GAGs and the urobiome that may play a
role in rUTI pathobiology
Urinary Glycosaminoglycans Are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women
Glycosaminoglycans (GAGs) are linear, negatively charged
polysaccharides
composed of repeating disaccharide units of uronic acid and amino
sugars. The luminal surface of the bladder epithelium is coated with
a GAG layer. These urothelial GAGs are thought to provide a protective
barrier and serve as a potential interaction site with the urinary
microbiome (urobiome). Previous studies have profiled urinary GAG
composition in mixed cohorts, but the urinary GAG composition in postmenopausal
women remains undefined. To investigate the relationship between GAGs
and recurrent urinary tract infection (rUTI), we profiled urinary
GAGs in a controlled cohort of postmenopausal women. We found that
chondroitin sulfate (CS) is the major urinary GAG in postmenopausal
women and that urinary CS was elevated in women with active rUTI.
We also associated urinary GAGs with urobiome composition and identified
bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas
somerae, and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid,
and bacterial species associated with vaginal dysbiosis were negatively
correlated with urinary CS. Altogether, this work defines changes
in urinary GAG composition associated with rUTI and identifies new
associations between urinary GAGs and the urobiome that may play a
role in rUTI pathobiology
Urinary Glycosaminoglycans Are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women
Glycosaminoglycans (GAGs) are linear, negatively charged
polysaccharides
composed of repeating disaccharide units of uronic acid and amino
sugars. The luminal surface of the bladder epithelium is coated with
a GAG layer. These urothelial GAGs are thought to provide a protective
barrier and serve as a potential interaction site with the urinary
microbiome (urobiome). Previous studies have profiled urinary GAG
composition in mixed cohorts, but the urinary GAG composition in postmenopausal
women remains undefined. To investigate the relationship between GAGs
and recurrent urinary tract infection (rUTI), we profiled urinary
GAGs in a controlled cohort of postmenopausal women. We found that
chondroitin sulfate (CS) is the major urinary GAG in postmenopausal
women and that urinary CS was elevated in women with active rUTI.
We also associated urinary GAGs with urobiome composition and identified
bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas
somerae, and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid,
and bacterial species associated with vaginal dysbiosis were negatively
correlated with urinary CS. Altogether, this work defines changes
in urinary GAG composition associated with rUTI and identifies new
associations between urinary GAGs and the urobiome that may play a
role in rUTI pathobiology