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result(s) for
"Cabrera, Claudia"
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Signatures of inflammation and impending multiple organ dysfunction in the hyperacute phase of trauma: A prospective cohort study
by
O’Dwyer, Michael
,
Pennington, Daniel J.
,
Watson, David
in
Acute Disease
,
Adult
,
Bioinformatics
2017
Severe trauma induces a widespread response of the immune system. This \"genomic storm\" can lead to poor outcomes, including Multiple Organ Dysfunction Syndrome (MODS). MODS carries a high mortality and morbidity rate and adversely affects long-term health outcomes. Contemporary management of MODS is entirely supportive, and no specific therapeutics have been shown to be effective in reducing incidence or severity. The pathogenesis of MODS remains unclear, and several models are proposed, such as excessive inflammation, a second-hit insult, or an imbalance between pro- and anti-inflammatory pathways. We postulated that the hyperacute window after trauma may hold the key to understanding how the genomic storm is initiated and may lead to a new understanding of the pathogenesis of MODS.
We performed whole blood transcriptome and flow cytometry analyses on a total of 70 critically injured patients (Injury Severity Score [ISS] ≥ 25) at The Royal London Hospital in the hyperacute time period within 2 hours of injury. We compared transcriptome findings in 36 critically injured patients with those of 6 patients with minor injuries (ISS ≤ 4). We then performed flow cytometry analyses in 34 critically injured patients and compared findings with those of 9 healthy volunteers. Immediately after injury, only 1,239 gene transcripts (4%) were differentially expressed in critically injured patients. By 24 hours after injury, 6,294 transcripts (21%) were differentially expressed compared to the hyperacute window. Only 202 (16%) genes differentially expressed in the hyperacute window were still expressed in the same direction at 24 hours postinjury. Pathway analysis showed principally up-regulation of pattern recognition and innate inflammatory pathways, with down-regulation of adaptive responses. Immune deconvolution, flow cytometry, and modular analysis suggested a central role for neutrophils and Natural Killer (NK) cells, with underexpression of T- and B cell responses. In the transcriptome cohort, 20 critically injured patients later developed MODS. Compared with the 16 patients who did not develop MODS (NoMODS), maximal differential expression was seen within the hyperacute window. In MODS versus NoMODS, 363 genes were differentially expressed on admission, compared to only 33 at 24 hours postinjury. MODS transcripts differentially expressed in the hyperacute window showed enrichment among diseases and biological functions associated with cell survival and organismal death rather than inflammatory pathways. There was differential up-regulation of NK cell signalling pathways and markers in patients who would later develop MODS, with down-regulation of neutrophil deconvolution markers. This study is limited by its sample size, precluding more detailed analyses of drivers of the hyperacute response and different MODS phenotypes, and requires validation in other critically injured cohorts.
In this study, we showed how the hyperacute postinjury time window contained a focused, specific signature of the response to critical injury that led to widespread genomic activation. A transcriptomic signature for later development of MODS was present in this hyperacute window; it showed a strong signal for cell death and survival pathways and implicated NK cells and neutrophil populations in this differential response.
Journal Article
Caffeine metabolism during cultivation of oyster mushroom (Pleurotus ostreatus) with spent coffee grounds
by
Kertesz, Michael A.
,
Bell, Tina L.
,
Carrasco-Cabrera, Claudia P.
in
agar
,
Applied Microbial and Cell Physiology
,
Biomedical and Life Sciences
2019
In coffee-producing countries, waste products from coffee production are useful substrates for cultivation of
Pleurotus ostreatus
. This species is relatively easy to grow, coffee waste substrates are readily available and the mushroom fruiting bodies are a valuable source of nutrition and income. In developed countries, cultivation of
P. ostreatus
on spent coffee grounds (SCG) from coffee consumption is a novel way to recycle this urban waste product. Here, we studied the effect of SCG and caffeine on growth of a commercial strain of
P. ostreatus
in liquid and solid cultures, and on a commercial scale. The presence of caffeine inhibited mycelial growth on agar and in liquid culture in the laboratory. Increased levels of SCG in an SCG/sawdust substrate also delayed mycelial growth and delayed or prevented fruiting during commercial cultivation. Despite growth inhibition, partial degradation of caffeine to xanthine by
P. ostreatus
mycelium was observed in all SCG-containing substrate mixtures. Degradation of caffeine proceeded mainly via sequential
N-
demethylation to theophylline (1,3-dimethylxanthine) and 3-methylxanthine, although both paraxanthine and theobromine also accumulated in the substrate. Caffeine and its demethylated metabolites were also detected in fruiting bodies, but it was not clear whether caffeine metabolism occurred in the fruiting bodies themselves or whether caffeine metabolites were translocated there from the mycelium. Based on the caffeine concentrations measured in fruiting bodies after growth with SCG, it would be necessary to consume ~ 250 kg of fresh oyster mushrooms to obtain the amount of caffeine equivalent to one cup of espresso coffee, suggesting that the health impact of caffeine in these mushrooms is low. However, the ability of
P. ostreatus
to degrade caffeine indicates that this and other species in this genus may have potential applications in detoxification of coffee production wastes.
Journal Article
Somatic mutations of GNA11 and GNAQ in CTNNB1-mutant aldosterone-producing adenomas presenting in puberty, pregnancy or menopause
by
Jordan, Suzanne
,
Kuan, Jyn Ling
,
Berney, Daniel M.
in
631/208/514/1948
,
692/699/2743/1279
,
Adenoma
2021
Most aldosterone-producing adenomas (APAs) have gain-of-function somatic mutations of ion channels or transporters. However, their frequency in aldosterone-producing cell clusters of normal adrenal gland suggests a requirement for codriver mutations in APAs. Here we identified gain-of-function mutations in both
CTNNB1
and
GNA11
by whole-exome sequencing of 3/41 APAs. Further sequencing of known
CTNNB1
-mutant APAs led to a total of 16 of 27 (59%) with a somatic p.Gln209His, p.Gln209Pro or p.Gln209Leu mutation of
GNA11
or
GNAQ
. Solitary
GNA11
mutations were found in hyperplastic zona glomerulosa adjacent to double-mutant APAs. Nine of ten patients in our UK/Irish cohort presented in puberty, pregnancy or menopause. Among multiple transcripts upregulated more than tenfold in double-mutant APAs was
LHCGR
, the receptor for luteinizing or pregnancy hormone (human chorionic gonadotropin). Transfections of adrenocortical cells demonstrated additive effects of
GNA11
and
CTNNB1
mutations on aldosterone secretion and expression of genes upregulated in double-mutant APAs. In adrenal cortex,
GNA11/Q
mutations appear clinically silent without a codriver mutation of
CTNNB1
.
Sequence analysis identifies gain-of-function somatic mutations in
GNA11
or
GNAQ
in
CTNNB1
-mutant aldosterone-producing adenomas. Most patients with these mutations presented during puberty, pregnancy or menopause, with elevated LHCGR expression.
Journal Article
Bilirubin levels and kidney function decline: An analysis of clinical trial and real world data
2022
To evaluate if previously found associations between low serum bilirubin concentration and kidney function decline is independent of hemoglobin and other key confounders. Clinical trial data from the SAVOR-TIMI 53 trial as well as the UK primary care electronic healthcare records, Clinical Practice Research Datalink (CPRD), were used to construct three cohorts of patients at risk of chronic kidney disease (CKD). The randomized clinical trial (RCT) cohort from the subset of SAVOR-TIMI 53 trial consisted of 10,555 type-2 diabetic patients with increased risk of cardiovascular disease. The two observational data cohorts from CPRD consisted of 71,104 newly diagnosed type-2 diabetes (CPRD-DM2) and 82,065 newly diagnosed hypertensive (CPRD-HT) patients without diabetes. Cohorts were stratified according to baseline circulating total bilirubin levels to determine association on the primary end point of a 30% reduction from baseline in estimated glomerular filtration rate (eGFR) and the secondary end point of albuminuria. The confounder adjusted hazard ratios of the subpopulation with lower than median bilirubin levels compared to above median bilirubin levels for the primary end point were 1.18 (1.02-1.37), 1.12 (1.05-1.19) and 1.09 (1.01-1.17), for the secondary end point were 1.26 (1.06-1.52), 1.11 (1.01-1.21) and 1.18 (1.01-1.39) for SAVOR-TIMI 53, CPRD-DM2, CPRD-HT, respectively. Our findings are consistent across all cohorts and endpoints: lower serum bilirubin levels are associated with a greater kidney function decline independent of hemoglobin and other key confounders. This suggests that increased monitoring of kidney health in patients with lower bilirubin levels may be considered, especially for diabetic patients.
Journal Article
Does high sugar intake really alter the oral microbiota?: A systematic review
by
Angarita‐Díaz, María del Pilar
,
Cabrera‐Arango, Claudia L.
,
Bedoya‐Correa, Claudia M.
in
Bacteria
,
Bacteria - genetics
,
Child
2022
Objectives
Diet is one of the main factors influencing the diversity and interactions of the oral microbiota. The purpose of this study is to determine the impact of sugar intake on the microbial diversity and bacteria that predominate under these conditions.
Material and Methods
A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guide, using the PubMed, Scopus, and Science Direct databases and combinations of the words “microbiota,” “microbiology,” “bacteria,” “sugars,” “dysbiosis,” “caries,” “microbiome,” “oral microbial,” and “oral microbiota profile pattern.” The selection criteria included year, language, type of publication, comparison of microbiota during low and high sugar intake, and bacterial identification by molecular sequencing of the 16S subunit of ribosomal RNA.
Results
Out of a total of 374 papers that came up after the initial search, 8 met the criteria for this review. The papers included research on populations comprising children, young adults, and adults, with most of the studies reporting selection criteria for the participants and using validated instruments to determine sugar intake. Apart from one study, all others reported for high sugar intake conditions a significant decrease in microbial diversity of the oral microbiome and the predominance of several bacterial genera or species, including Streptococcus, Scardovia, Veillonella, Rothia, Actinomyces, and Lactobacillus.
Conclusions
Sugar‐rich diets have a significantly unfavorable effect on the diversity and balance of oral microbiota; however, further studies are required to determine the exact role of sugar in microbial interactions.
Journal Article
Heteroplasmic mitochondrial DNA variants in cardiovascular diseases
by
Griffin, Helen
,
Coxhead, Jonathan
,
Little, Louis
in
Amino acid sequence
,
Biology and life sciences
,
Cardiovascular disease
2022
Mitochondria are implicated in the pathogenesis of cardiovascular diseases (CVDs) but the reasons for this are not well understood. Maternally-inherited population variants of mitochondrial DNA (mtDNA) which affect all mtDNA molecules (homoplasmic) are associated with cardiometabolic traits and the risk of developing cardiovascular disease. However, it is not known whether mtDNA mutations only affecting a proportion of mtDNA molecules (heteroplasmic) also play a role. To address this question, we performed a high-depth (~1000-fold) mtDNA sequencing of blood DNA in 1,399 individuals with hypertension (HTN), 1,946 with ischemic heart disease (IHD), 2,146 with ischemic stroke (IS), and 723 healthy controls. We show that the
per
individual burden of heteroplasmic single nucleotide variants (mtSNVs) increases with age. The age-effect was stronger for low-level heteroplasmies (heteroplasmic fraction, HF, 5–10%), likely reflecting acquired somatic events based on trinucleotide mutational signatures. After correcting for age and other confounders, intermediate heteroplasmies (HF 10–95%) were more common in hypertension, particularly involving non-synonymous variants altering the amino acid sequence of essential respiratory chain proteins. These findings raise the possibility that heteroplasmic mtSNVs play a role in the pathophysiology of hypertension.
Journal Article
Association between COPD exacerbations and lung function decline during maintenance therapy
by
Cabrera, Claudia
,
Darken, Patrick
,
Voorham, Jaco
in
Administration, Inhalation
,
Adrenal Cortex Hormones - administration & dosage
,
Adrenal Cortex Hormones - therapeutic use
2020
BackgroundLittle is known about the impact of exacerbations on COPD progression or whether inhaled corticosteroid (ICS) use and blood eosinophil count (BEC) affect progression. We aimed to assess this in a prospective observational study.MethodsThe study population included patients with mild to moderate COPD, aged ≥35 years, with a smoking history, who were followed up for ≥3 years from first to last spirometry recording using two large UK electronic medical record databases: Clinical Practice Research Datalink (CPRD) and Optimum Patient Care Research Database (OPCRD). Multilevel mixed-effects linear regression models were used to determine the relationship between annual exacerbation rate following initiation of therapy (ICS vs non-ICS) and FEV1 decline. Effect modification by blood eosinophils was studied through interaction terms.ResultsOf 12178 patients included (mean age 66 years; 48% female), 8981 (74%) received ICS. In patients with BEC ≥350 cells/µL not on ICS, each exacerbation was associated with subsequent acceleration of FEV1 decline of 19.4 mL/year (95% CI 12.0 to 26.7, p<0.0001). This excess decline was reduced by 15.1 mL/year (6.6 to 23.6) to 4.3 mL/year (1.9 to 6.7, p<0.0001) in those with BEC ≥350 cells/µL treated with ICS.ConclusionExacerbations are associated with a more rapid loss of lung function among COPD patients with elevated blood eosinophils, defined as ≥350 cells/µL, not treated with ICS. More aggressive prevention of exacerbations using ICS in such patients may prevent excess loss of lung function.
Journal Article
Contemporary rates and predictors of fast progression of chronic kidney disease in adults with and without diabetes mellitus
2018
Background
Chronic kidney disease (CKD) is highly prevalent but identification of patients at high risk for fast CKD progression before reaching end-stage renal disease in the short-term has been challenging. Whether factors associated with fast progression vary by diabetes status is also not well understood. We examined a large community-based cohort of adults with CKD to identify predictors of fast progression during the first 2 years of follow-up in the presence or absence of diabetes mellitus.
Methods
Within a large integrated healthcare delivery system in northern California, we identified adults with estimated glomerular filtration rate (eGFR) 30–59 ml/min/1.73 m
2
by CKD-EPI equation between 2008 and 2010 who had no previous dialysis or renal transplant, who had outpatient serum creatinine values spaced 10–14 months apart and who did not initiate renal replacement therapy, die or disenroll during the first 2 years of follow-up. Through 2012, we calculated the annual rate of change in eGFR and classified patients as fast progressors if they lost > 4 ml/min/1.73 m
2
per year. We used multivariable logistic regression to identify patient characteristics that were independently associated with fast CKD progression stratified by diabetes status.
Results
We identified 36,195 eligible adults with eGFR 30–59 ml/min/1.73 m
2
and mean age 73 years, 55% women, 11% black, 12% Asian/Pacific Islander and 36% with diabetes mellitus. During 24-month follow-up, fast progression of CKD occurred in 23.0% of patients with diabetes vs. 15.3% of patients without diabetes. Multivariable predictors of fast CKD progression that were similar by diabetes status included proteinuria, age ≥ 80 years, heart failure, anemia and higher systolic blood pressure. Age 70–79 years, prior ischemic stroke, current or former smoking and lower HDL cholesterol level were also predictive in patients without diabetes, while age 18–49 years was additionally predictive in those with diabetes.
Conclusions
In a large, contemporary population of adults with eGFR 30–59 ml/min/1.73 m
2
, accelerated progression of kidney dysfunction within 2 years affected ~ 1 in 4 patients with diabetes and ~ 1 in 7 without diabetes. Regardless of diabetes status, the strongest independent predictors of fast CKD progression included proteinuria, elevated systolic blood pressure, heart failure and anemia.
Journal Article
Somatic mutations of CADM1 in aldosterone-producing adenomas and gap junction-dependent regulation of aldosterone production
2023
Aldosterone-producing adenomas (APAs) are the commonest curable cause of hypertension. Most have gain-of-function somatic mutations of ion channels or transporters. Herein we report the discovery, replication and phenotype of mutations in the neuronal cell adhesion gene
CADM1
. Independent whole exome sequencing of 40 and 81 APAs found intramembranous p.Val380Asp or p.Gly379Asp variants in two patients whose hypertension and periodic primary aldosteronism were cured by adrenalectomy. Replication identified two more APAs with each variant (total,
n
= 6). The most upregulated gene (10- to 25-fold) in human adrenocortical H295R cells transduced with the mutations (compared to wildtype) was
CYP11B2
(aldosterone synthase), and biological rhythms were the most differentially expressed process.
CADM1
knockdown or mutation inhibited gap junction (GJ)-permeable dye transfer. GJ blockade by Gap27 increased
CYP11B2
similarly to
CADM1
mutation. Human adrenal zona glomerulosa (ZG) expression of GJA1 (the main GJ protein) was patchy, and annular GJs (sequelae of GJ communication) were less prominent in CYP11B2-positive micronodules than adjacent ZG. Somatic mutations of
CADM1
cause reversible hypertension and reveal a role for GJ communication in suppressing physiological aldosterone production.
Recurrent somatic mutations altering residues in the transmembrane domain of
CADM1
are identified in aldosterone-producing adenomas. Follow-up studies implicate a role of gap junction communication in regulating aldosterone production.
Journal Article
IGSF10 mutations dysregulate gonadotropin‐releasing hormone neuronal migration resulting in delayed puberty
2016
Early or late pubertal onset affects up to 5% of adolescents and is associated with adverse health and psychosocial outcomes. Self‐limited delayed puberty (DP) segregates predominantly in an autosomal dominant pattern, but the underlying genetic background is unknown. Using exome and candidate gene sequencing, we have identified rare mutations in
IGSF10
in 6 unrelated families, which resulted in intracellular retention with failure in the secretion of mutant proteins.
IGSF10
mRNA was strongly expressed in embryonic nasal mesenchyme, during gonadotropin‐releasing hormone (GnRH) neuronal migration to the hypothalamus.
IGSF10
knockdown caused a reduced migration of immature GnRH neurons
in vitro
, and perturbed migration and extension of GnRH neurons in a gnrh3:EGFP zebrafish model. Additionally, loss‐of‐function mutations in
IGSF10
were identified in hypothalamic amenorrhea patients. Our evidence strongly suggests that mutations in
IGSF10
cause DP in humans, and points to a common genetic basis for conditions of functional hypogonadotropic hypogonadism (HH). While dysregulation of GnRH neuronal migration is known to cause permanent HH, this is the first time that this has been demonstrated as a causal mechanism in DP.
‡
Synopsis
Self‐limited delayed puberty (DP) has strong familial inheritance, but the underlying genetic determinants are unknown. IGSF10 deficiency is found to affect embryonic GnRH neuronal migration and results in DP in humans.
Pathogenic mutations in IGSF10 are found in patients with self‐limited delayed puberty.
IGSF10 is a gene of previously unclear function with no known human mutations.
IGSF10 is expressed within the nasal mesenchyme during fetal development, in a pattern similar to known chemokines that direct migrational GnRH neurons to the hypothalamus.
Knockdown of IGSF10 led to a reduced migration of GnRH neurons
in vitro
and in a transgenic zebrafish model.
IGSF10 loss‐of‐function mutations were also identified in patients with hypothalamic amenorrhea, suggesting an overlapping genetic and mechanistic basis between different types of functional hypogonadotropic hypogonadism, including DP and hypothalamic amenorrhea.
Graphical Abstract
Self‐limited delayed puberty (DP) has strong familial inheritance, but the underlying genetic determinants are unknown. IGSF10 deficiency is found to affect embryonic GnRH neuronal migration and results in DP in humans.
Journal Article