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1.
Proc Natl Acad Sci U S A ; 119(20): e2111294119, 2022 05 17.
Article in English | MEDLINE | ID: mdl-35537050

ABSTRACT

To meet the 1.5 °C target, methane (CH4) from ruminants must be reduced by 11 to 30% by 2030 and 24 to 47% by 2050 compared to 2010 levels. A meta-analysis identified strategies to decrease product-based (PB; CH4 per unit meat or milk) and absolute (ABS) enteric CH4 emissions while maintaining or increasing animal productivity (AP; weight gain or milk yield). Next, the potential of different adoption rates of one PB or one ABS strategy to contribute to the 1.5 °C target was estimated. The database included findings from 430 peer-reviewed studies, which reported 98 mitigation strategies that can be classified into three categories: animal and feed management, diet formulation, and rumen manipulation. A random-effects meta-analysis weighted by inverse variance was carried out. Three PB strategies­namely, increasing feeding level, decreasing grass maturity, and decreasing dietary forage-to-concentrate ratio­decreased CH4 per unit meat or milk by on average 12% and increased AP by a median of 17%. Five ABS strategies­namely CH4 inhibitors, tanniferous forages, electron sinks, oils and fats, and oilseeds­decreased daily methane by on average 21%. Globally, only 100% adoption of the most effective PB and ABS strategies can meet the 1.5 °C target by 2030 but not 2050, because mitigation effects are offset by projected increases in CH4 due to increasing milk and meat demand. Notably, by 2030 and 2050, low- and middle-income countries may not meet their contribution to the 1.5 °C target for this same reason, whereas high-income countries could meet their contributions due to only a minor projected increase in enteric CH4 emissions.


Subject(s)
Methane , Ruminants , Africa , Animals , Developing Countries , Europe , Global Warming/prevention & control , Methane/analysis
2.
J Med Genet ; 60(11): 1116-1126, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37308287

ABSTRACT

BACKGROUND: Mirror movements are involuntary movements of one hand that mirror intentional movements of the other hand. Congenital mirror movements (CMM) is a rare genetic disorder with autosomal dominant inheritance, in which mirror movements are the main neurological manifestation. CMM is associated with an abnormal decussation of the corticospinal tract, a major motor tract for voluntary movements. RAD51 is known to play a key role in homologous recombination with a critical function in DNA repair. While RAD51 haploinsufficiency was first proposed to explain CMM, other mechanisms could be involved. METHODS: We performed Sanger sequencing of RAD51 in five newly identified CMM families to identify new pathogenic variants. We further investigated the expression of wild-type and mutant RAD51 in the patients' lymphoblasts at mRNA and protein levels. We then characterised the functions of RAD51 altered by non-truncating variants using biochemical approaches. RESULTS: The level of wild-type RAD51 protein was lower in the cells of all patients with CMM compared with their non-carrier relatives. The reduction was less pronounced in asymptomatic carriers. In vitro, mutant RAD51 proteins showed loss-of-function for polymerisation, DNA binding and strand exchange activity. CONCLUSION: Our study demonstrates that RAD51 haploinsufficiency, including loss-of-function of non-truncating variants, results in CMM. The incomplete penetrance likely results from post-transcriptional compensation. Changes in RAD51 levels and/or polymerisation properties could influence guidance of the corticospinal axons during development. Our findings open up new perspectives to understand the role of RAD51 in neurodevelopment.

3.
Arch Anim Nutr ; : 1-17, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38907616

ABSTRACT

In Africa, a wide variety of diets (forage + crop co-products or other agricultural by-products) is being used by livestock farmers in different production systems to adapt to climate change. This study aimed to assess the performance of various local feeding strategies on Sudanese Fulani zebu cattle. Two experiments were carried out on 10 steers aged initially 33 months (142 kg body weight - BW). The animals were fed eight different diets at an intake level of 3.2% LW in dry matter (DM), including two control diets of 100% rangeland forage (100% RF) and six experimental diets made up of forage and crop co-products (75:25 DM ratio). In the first experiment, the control diet was made up of rangeland forage (RF) and supplements consisted of four cereal co-products (CC), i.e. maize, sorghum, millet, and rice straws. In the second experiment, the control diet consisted of Panicum maximum (Pmax) hay, and the supplements tested were two legume co-products (LC), i.e. cowpea and peanut haulms. Each experiment lasted 3 weeks, including 2 weeks of adaptation to the diet and 1 week of data collection on individual animals (intake, apparent digestibility, and enteric methane). The NDF content of the diets was different within each experiment (p < 0.05). Among diets containing CC, DM intake [g/kg BW] was significantly higher (+31%; p = 0.025) for the diet containing rice straw than for the other diets, which showed similar levels to the RF diet. Among diets containing LC, intake was significantly higher (p = 0.004) than for the Pmax diet. Intake was higher for the peanut haulm diet than for the cowpea haulm diet. The DM digestibility was similar between the different diets in each experiment. Enteric methane (eCH4) yield [g/kg DMI] from the CC and LC-containing diets were reduced by an average of 23% and 20% compared to the RF and Pmax control diets respectively. Raising awareness among agro-pastoralists about the use of crop co-products offers real prospects for eCH4 emissions mitigation in the Sahel region.

4.
Nephrol Dial Transplant ; 38(5): 1192-1203, 2023 05 04.
Article in English | MEDLINE | ID: mdl-36043422

ABSTRACT

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA) kinetic in ANCA-associated vasculitis with glomerulonephritis (AAV-GN) has been suggested to be associated with AAV relapse. Few studies have focused on its association with renal prognosis. Thus we aimed to investigate the relationship between ANCA specificity and the evolutive profile and renal outcomes. METHODS: This multicentric retrospective study included patients diagnosed with ANCA-GN since 1 January 2000. Patients without ANCA at diagnosis and with fewer than three ANCA determinations during follow-up were excluded. We analysed estimated glomerular filtration rate (eGFR) variation, renal-free survival and relapse-free survival according to three ANCA profiles (negative, recurrent and persistent) and to ANCA specificity [myeloperoxidase (MPO) or proteinase 3 (PR3)]. RESULTS: Over a follow-up of 56 months [interquartile range (IQR) 34-101], a median of 19 (IQR 13-25) ANCA determinations were performed for the 134 included patients. Patients with a recurrent/persistent ANCA profile had a lower relapse-free survival (P = .019) and tended to have a lower renal survival (P = .053) compared with those with a negative ANCA profile. Patients with a recurrent/persistent MPO-ANCA profile had the shortest renal survival (P = .015) and those with a recurrent/persistent PR3-ANCA profile had the worst relapse-free survival (P = .013) compared with other profiles. The negative ANCA profile was associated with a greater eGFR recovery. In multivariate regression analysis, it was an independent predictor of a 2-fold increase in eGFR at 2 years [odds ratio 6.79 (95% confidence interval 1.78-31.4), P = .008]). CONCLUSION: ANCA kinetic after an ANCA-GN diagnosis is associated with outcomes. MPO-ANCA recurrence/persistence identifies patients with a lower potential of renal recovery and a higher risk of kidney failure, while PR3-ANCA recurrence/persistence identifies patients with a greater relapse risk. Thus ANCA kinetics may help identify patients with a smouldering disease.


Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis , Glomerulonephritis , Humans , Antibodies, Antineutrophil Cytoplasmic , Retrospective Studies , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/complications , Kidney , Chronic Disease , Myeloblastin , Peroxidase
5.
Blood Purif ; 52(3): 309-318, 2023.
Article in English | MEDLINE | ID: mdl-36215951

ABSTRACT

INTRODUCTION: Online hemodiafiltration (OL-HDF) and hemodialysis (HD) using high-performance membranes such as adsorptive, medium cut-off (MCO), and super high-flux (SHF) dialyzers have been implemented to enhance the removal of middle molecules (MM). The aim of this study was to compare the efficacy of different dialysis strategies and dialyzers on small solutes and MM reduction ratio (RR) and mass removal. METHODS: We performed a prospective study in 8 HD patients. Each patient underwent 9 dialysis sessions: seven sessions on HD using either Theranova 500™, Elisio 21H™, Renak PS-2.0W™, Filtryzer BK-2.1F™, Vie 21X™, TS-2.1UL™ or FDY 210-GW™ dialyzers and two sessions on OL-HDF using Elisio 21H™ or Renak PS-2.0W™ dialyzers. RESULTS: Urea mass removal and RR were similar between all dialysis strategies. The lowest beta2-microglobulin RR was achieved with Filtryzer BK-2.1F™ HD (p < 0.05). Compared to Elisio 21H™ HD, Renak PS-2.0W™ OL-HDF produced higher beta2-microglobulin mass removal (181 ± 46 vs. 317 ± 161 mg, p < 0.05). Theranova 500™ HD, Vie 21X™ HD, FDY 210-GW™ HD, Elisio 21H™ OL-HDF, and Renak PS-2.0W™ OL-HDF induced higher RR for kappa and lambda FLC, as compared to Elisio 21H™ HD and Filtryzer BK-2.1F™ HD (p < 0.05). Renak PS-2.0W™ OL-HDF achieved higher kappa FLC mass removal compared to Elisio 21H™ HD (563 ± 515 vs. 141 ± 47 mg, p < 0.01) and to Renak PS-2.0W™ HD (563 ± 515 vs. 153 ± 25 mg, p < 0.05). Albumin loss varied from 0.02 ± 0.05 to 7.6 ± 3.8 g/session with Elisio 21H™ HD and Renak PS-2.0W™ OL-HDF, respectively. Compared to all other strategies, Renak PS-2.0W™ OL-HDF induced a significantly higher albumin loss (p < 0.05). CONCLUSION: This study confirms that albumin loss and removal of MM are similar using conventional Elisio 21H™ OL-HDF, MCO-HD, and SHF type V dialyzers. Although Renak PS-2.0W™ OL-HDF provides high performance for MM depuration, this protein-permeable dialyzer should not be used in OL-HDF because of excessive albumin loss.


Subject(s)
Hemodiafiltration , Humans , Uremic Toxins , Prospective Studies , Renal Dialysis , Albumins
6.
Methods ; 186: 59-67, 2021 02.
Article in English | MEDLINE | ID: mdl-33253811

ABSTRACT

The aims of this work were to study on dairy farm conditions: i) the repeatability of long-term enteric CH4 emissions measurement from lactating dairy cows using GreenFeed (GF); ii) the ranking of dairy cows according to their CH4 emissions across diets. Forty-five Holstein lactating dairy cows were randomly assigned to 3 equivalent groups at the beginning of their lactation. The experiment was composed of 3 successive periods: i) pre-experimental period (weeks 1 to 5) in which all cows received a common diet; ii) a dietary treatment transition period (weeks 6 to 10); and iii) an experimental period (weeks 11 to 26) in which each group was fed a different diet. Experimental diets were formulated to generate more or less CH4 production: i) a diet based on ryegrass silage and concentrates, low in starch and lipid, designed to induce high CH4 emissions (CH4+); ii) a diet based on maize silage and concentrates, rich in starch, designed to induce intermediate CH4 emissions (CH4int); iii) a diet based on maize silage and concentrates, rich in starch and lipid, designed to induce low CH4 emissions (CH4-). Gas emissions were individually measured using GF systems. Repeatability of gas emissions, dry matter intake (DMI) and dairy performances measurements was calculated from data averaged over 1, 2, 4, and 8 weeks for each animal. Hierarchical cluster analysis was performed to rank individual animals according to their CH4 emissions. No significant differences were observed for daily CH4 emissions (g/day) among diets, because of lower DMI of CH4+ cows. When CH4 emissions were referred to units of DMI or milk, the differences among diets emerged as significant and persistent over the observed period of lactation. Repeatability values of gas emissions measurements were higher than 0.7 averaged over 8 weeks of measurement, but still higher than 0.6 for CH4 g/day, CO2 g/day, CH4 g/kg milk, and CH4/CO2 even averaging only 2 weeks of measurement. The repeatability of CH4 emissions measurement was systematically lower than those of DMI or dairy performance parameters, like milk and FPCM yield, irrespective of the averaged measurement period. The dairy cow ranking was not stable over time between all individuals or within any of the diets. In our experimental conditions, the GF performance in the long term can be considered reliable in differentiating dairy herds by their CH4 emissions according to diets with different methanogenic potential, but did not allow the ranking of individual dairy cows within a same diet. Our data highlight the importance of phenotyping animals across environment in which they will be expected to perform.


Subject(s)
Ecological Parameter Monitoring/methods , Gastrointestinal Microbiome/physiology , Greenhouse Effect/prevention & control , Methane/biosynthesis , Silage , Animals , Biological Variation, Population , Cattle , Ecological Parameter Monitoring/statistics & numerical data , Farms/statistics & numerical data , Female , Lactation/metabolism , Rumen/metabolism , Rumen/microbiology
7.
J Dairy Res ; : 1-10, 2022 Aug 30.
Article in English | MEDLINE | ID: mdl-36039952

ABSTRACT

The experiment reported in this research paper aimed to evaluate the effects of high-starch or starch and oil-supplemented diets on rumen and faecal bacteria, and explore links between the structure of bacterial communities and milk fatty acid (FA) profiles. We used four Holstein dairy cows in a 4 × 4 Latin square design. Cows were fed a diet rich in cereals (high-starch diet with 23% starch content on dry matter (DM) basis), a diet supplemented with saturated FA from Ca salts of palm oil + 18% DM starch, a diet with high content of monounsaturated FA (from extruded rapeseeds) + 18% DM starch or a diet rich in polyunsaturated FA (from extruded sunflower seeds) + 17% DM starch. At the end of each experimental period, cows were sampled for rumen and faecal contents, which were used for DNA extraction and amplicon sequencing. Partial least squares (PLS) regression analysis highlighted diet-related changes in both rumen and faecal bacterial structures. Sparse PLS discriminant analysis was further employed to identify biologically relevant operational taxonomical units (OTUs) driving these differences. Our results show that Butyrivibrio discriminated the high-starch diet and linked positively with higher concentrations of milk odd- and branched-chain FA. YS2-related OTUs were key taxa distinguishing diets supplemented with Ca salts of palm oil or sunflower seeds and correlated positively with linoleic acid in milk. Similarly, diets modulated faecal bacterial composition. However, correlations between changes in faecal and rumen bacteria were poor. With this work, we demonstrated that high-starch or lipid-supplemented diets affect rumen and faecal bacterial community structure, and these changes could have a knock-on effect on milk FA profiles.

8.
Hum Mutat ; 42(4): 408-420, 2021 04.
Article in English | MEDLINE | ID: mdl-33410562

ABSTRACT

ABCC8 encodes the SUR1 subunit of the ß-cell ATP-sensitive potassium channel whose loss of function causes congenital hyperinsulinism (CHI). Molecular diagnosis is critical for optimal management of CHI patients. Unfortunately, assessing the impact of ABCC8 variants on RNA splicing remains very challenging as this gene is poorly expressed in leukocytes. Here, we performed bioinformatics analysis and cell-based minigene assays to assess the impact on splicing of 13 ABCC8 variants identified in 20 CHI patients. Next, channel properties of SUR1 proteins expected to originate from minigene-detected in-frame splicing defects were analyzed after ectopic expression in COSm6 cells. Out of the analyzed variants, seven induced out-of-frame splicing defects and were therefore classified as recessive pathogenic, whereas two led to skipping of in-frame exons. Channel functional analysis of the latter demonstrated their pathogenicity. Interestingly, the common rs757110 SNP increased exon skipping in our system suggesting that it may act as a disease modifier factor. Our strategy allowed determining the pathogenicity of all selected ABCC8 variants, and CHI-inheritance pattern for 16 out of the 20 patients. This study highlights the value of combining RNA and protein functional approaches in variant interpretation and reveals the minigene splicing assay as a new tool for CHI molecular diagnostics.


Subject(s)
Computational Biology , Congenital Hyperinsulinism , Sulfonylurea Receptors , Congenital Hyperinsulinism/diagnosis , Congenital Hyperinsulinism/genetics , Exons/genetics , Humans , RNA Splicing/genetics , Sulfonylurea Receptors/genetics
9.
Acta Neuropathol ; 141(1): 39-65, 2021 01.
Article in English | MEDLINE | ID: mdl-33079262

ABSTRACT

Several lines of recent evidence indicate that the amyloid precursor protein-derived C-terminal fragments (APP-CTFs) could correspond to an etiological trigger of Alzheimer's disease (AD) pathology. Altered mitochondrial homeostasis is considered an early event in AD development. However, the specific contribution of APP-CTFs to mitochondrial structure, function, and mitophagy defects remains to be established. Here, we demonstrate in neuroblastoma SH-SY5Y cells expressing either APP Swedish mutations, or the ß-secretase-derived APP-CTF fragment (C99) combined with ß- and γ-secretase inhibition, that APP-CTFs accumulation independently of Aß triggers excessive mitochondrial morphology alteration (i.e., size alteration and cristae disorganization) associated with enhanced mitochondrial reactive oxygen species production. APP-CTFs accumulation also elicit basal mitophagy failure illustrated by enhanced conversion of LC3, accumulation of LC3-I and/or LC3-II, non-degradation of SQSTM1/p62, inconsistent Parkin and PINK1 recruitment to mitochondria, enhanced levels of membrane and matrix mitochondrial proteins, and deficient fusion of mitochondria with lysosomes. We confirm the contribution of APP-CTFs accumulation to morphological mitochondria alteration and impaired basal mitophagy in vivo in young 3xTgAD transgenic mice treated with γ-secretase inhibitor as well as in adeno-associated-virus-C99 injected mice. Comparison of aged 2xTgAD and 3xTgAD mice indicates that, besides APP-CTFs, an additional contribution of Aß to late-stage mitophagy activation occurs. Importantly, we report on mitochondrial accumulation of APP-CTFs in human post-mortem sporadic AD brains correlating with mitophagy failure molecular signature. Since defective mitochondria homeostasis plays a pivotal role in AD pathogenesis, targeting mitochondrial dysfunctions and/or mitophagy by counteracting early APP-CTFs accumulation may represent relevant therapeutic interventions in AD.


Subject(s)
Alzheimer Disease/pathology , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Brain/pathology , Mitochondria/pathology , Mitochondria/ultrastructure , Mitophagy/genetics , Aged , Aged, 80 and over , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid Precursor Protein Secretases/metabolism , Animals , Aspartic Acid Endopeptidases/antagonists & inhibitors , Aspartic Acid Endopeptidases/metabolism , Autopsy , Cell Line , Female , Humans , Membrane Potential, Mitochondrial , Mice , Mitochondria/metabolism , Peptide Fragments/genetics , Peptide Fragments/metabolism , Reactive Oxygen Species/metabolism
10.
J Sci Food Agric ; 101(8): 3394-3403, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33222175

ABSTRACT

BACKGROUND: A robust proxy for estimating methane (CH4 ) emissions of individual dairy cows would be valuable especially for selective breeding. This study aimed to improve the robustness and accuracy of prediction models that estimate daily CH4 emissions from milk Fourier transform mid-infrared (FT-MIR) spectra by (i) increasing the reference dataset and (ii) adjusting for routinely recorded phenotypic information. Prediction equations for CH4 were developed using a combined dataset including daily CH4 measurements (n = 1089; g d-1 ) collected using the SF6 tracer technique (n = 513) and measurements using respiration chambers (RC, n = 576). Furthermore, in addition to the milk FT-MIR spectra, the variables of milk yield (MY) on the test day, parity (P) and breed (B) of cows were included in the regression analysis as explanatory variables. RESULTS: Models developed based on a combined RC and SF6 dataset predicted the expected pattern in CH4 values (in g d-1 ) during a lactation cycle, namely an increase during the first weeks after calving followed by a gradual decrease until the end of lactation. The model including MY, P and B information provided the best prediction results (cross-validation statistics: R2 = 0.68 and standard error = 57 g CH4 d-1 ). CONCLUSIONS: The models developed accounted for more of the observed variability in CH4 emissions than previously developed models and thus were considered more robust. This approach is suitable for large-scale studies (e.g. animal genetic evaluation) where robustness is paramount for accurate predictions across a range of animal conditions. © 2020 Society of Chemical Industry.


Subject(s)
Cattle/metabolism , Methane/analysis , Milk/chemistry , Spectrophotometry, Infrared/methods , Animals , Female , Lactation , Methane/metabolism , Milk/metabolism , Pregnancy
11.
Hum Mutat ; 41(5): 884-905, 2020 05.
Article in English | MEDLINE | ID: mdl-32027066

ABSTRACT

The most common genetic cause of neonatal diabetes and hyperinsulinism is pathogenic variants in ABCC8 and KCNJ11. These genes encode the subunits of the ß-cell ATP-sensitive potassium channel, a key component of the glucose-stimulated insulin secretion pathway. Mutations in the two genes cause dysregulated insulin secretion; inactivating mutations cause an oversecretion of insulin, leading to congenital hyperinsulinism, whereas activating mutations cause the opposing phenotype, diabetes. This review focuses on variants identified in ABCC8 and KCNJ11, the phenotypic spectrum and the treatment implications for individuals with pathogenic variants.


Subject(s)
Congenital Hyperinsulinism/genetics , Diabetes Mellitus/genetics , Insulin-Secreting Cells/metabolism , Mutation , Potassium Channels, Inwardly Rectifying/genetics , Sulfonylurea Receptors/genetics , Congenital Hyperinsulinism/diagnosis , Diabetes Mellitus/diagnosis , Gain of Function Mutation , Genetic Association Studies , Genetic Predisposition to Disease , Humans , Infant, Newborn , Loss of Function Mutation
12.
BMC Med ; 17(1): 132, 2019 07 11.
Article in English | MEDLINE | ID: mdl-31291970

ABSTRACT

BACKGROUND: Monogenic diabetes (MgD) accounts for 1-2% of all diabetes cases. In adults, MgD is difficult to distinguish from common diabetes causes. We assessed the diagnosis rate and genetic spectrum of MgD using next-generation sequencing in patients with late adolescence/adult-onset diabetes referred for a clinical suspicion of MgD. METHODS: This cross-sectional study was performed in 1564 probands recruited in 116 Endocrinology departments. Inclusion criteria were the absence of diabetes autoantibodies, and at least two of the three following criteria: an age ≤ 40 years and a body mass index (BMI) < 30 kg/m2 at diagnosis in the proband or in at least two relatives with diabetes, and a family history of diabetes in ≥ 2 generations. Seven genes (GCK, HNF1A, HNF4A, HNF1B, ABCC8, KCNJ11, and INS) were analyzed. Variant pathogenicity was assessed using current guidelines. RESULTS: Pathogenic variants were identified in 254 patients (16.2%) and in 23.2% of EuroCaucasian patients. Using more stringent selection criteria (family history of diabetes in ≥ 3 generations, age at diabetes ≤ 40 years and BMI < 30 kg/m2 in the proband, EuroCaucasian origin) increased the diagnosis rate to 43%, but with 70% of the identified cases being missed. GCK (44%), HNF1A (33%), and HNF4A (10%) accounted for the majority of the cases. HNF1B (6%), ABCC8/KCNJ11 (4.4%), and INS (2.8%) variants accounted for 13% of the cases. As compared to non-monogenic cases, a younger age, a lower BMI and the absence of diabetes symptoms at diagnosis, a EuroCaucasian origin, and a family history of diabetes in ≥ 3 generations were associated with MgD, but with wide phenotype overlaps between the two groups. In the total population, two clusters were identified, that mainly differed by the severity of diabetes at onset. MgDs were more prevalent in the milder phenotypic cluster. The phenotypes of the 59 patients (3.8%) with variants of uncertain significance were different from that of patients with pathogenic variants, but not from that of non-monogenic patients. CONCLUSION: Variants of HNF1B and the K-ATP channel genes were more frequently involved in MgD than previously reported. Phenotype overlapping makes the diagnosis of MgD difficult in adolescents/adults and underlies the benefit of NGS in clinically selected patients.


Subject(s)
Diabetes Mellitus, Type 2/diagnosis , Genetic Testing/methods , High-Throughput Nucleotide Sequencing/methods , Adolescent , Adult , Cross-Sectional Studies , Female , Humans , Male , Young Adult
13.
Appl Environ Microbiol ; 85(4)2019 02 15.
Article in English | MEDLINE | ID: mdl-30504215

ABSTRACT

Dietary supplementation with linseed, saponins, and nitrate is a promising methane mitigation strategy in ruminant production. Here, we aimed to assess the effects of these additives on the rumen microbiota in order to understand underlying microbial mechanisms of methane abatement. Two 2-by-2 factorial design studies were conducted simultaneously, which also allowed us to make a broad-based assessment of microbial responses. Eight nonlactating cows were fed diets supplemented with linseed or saponin in order to decrease hydrogen production and nitrate to affect hydrogen consumption; also, combinations of linseed plus nitrate or saponin plus nitrate were used to explore the interaction between dietary treatments. Previous work assessed effects on methane and fermentation patterns. Rumen microbes were studied by sequencing 18S and 16S rRNA genes and ITS1 amplicons. Methanogen activity was monitored by following changes in mcrA transcript abundance. Nitrate fed alone or in combination in both studies dramatically affected the composition and structure of rumen microbiota, although impacts were more evident in one of the studies. Linseed moderately modified only bacterial community structure. Indicator operational taxonomic unit (OTU) analysis revealed that both linseed and nitrate reduced the relative abundance of hydrogen-producing Ruminococcaceae Linseed increased the proportion of bacteria known to reduce succinate to propionate, whereas nitrate supplementation increased nitrate-reducing bacteria and decreased the metabolic activity of rumen methanogens. Saponins had no effect on the microbiota. Inconsistency found between the two studies with nitrate supplementation could be explained by changes in microbial ecosystem functioning rather than changes in microbial community structure.IMPORTANCE This study aimed at identifying the microbial mechanisms of enteric methane mitigation when linseed, nitrate, and saponins were fed to nonlactating cows alone or in a combination. Hydrogen is a limiting factor in rumen methanogenesis. We hypothesized that linseed and saponins would affect hydrogen producers and nitrate would affect hydrogen consumption, leading to reduced methane production in the rumen. Contrary to what was predicted, both linseed and nitrate had a deleterious effect on hydrogen producers; linseed also redirected hydrogen consumption toward propionate production, whereas nitrate stimulated the growth of nitrate-reducing and, hence, hydrogen-consuming bacterial taxa. This novel knowledge of microbial mechanisms involved in rumen methanogenesis provides insights for the development and optimization of methane mitigation strategies.


Subject(s)
Dietary Supplements , Flax/metabolism , Microbiota/drug effects , Nitrates/metabolism , Rumen/microbiology , Saponins/metabolism , Animal Feed , Animals , Archaea/classification , Archaea/genetics , Bacteria/classification , Bacteria/genetics , Cattle , Diet/veterinary , Digestion/drug effects , Drug Combinations , Fermentation , Hydrogen/metabolism , Methane/metabolism , Nitrates/pharmacology , RNA, Ribosomal, 16S/genetics , Saponins/pharmacology
14.
Heart Surg Forum ; 22(1): E057-E062, 2019 02 21.
Article in English | MEDLINE | ID: mdl-30802199

ABSTRACT

INTRODUCTION: Previous studies have shown that statin use before coronary surgery decreases the mortality and morbidity. This benefit was not clearly detected in isolated valve surgery. The aim of this study was to assess the effect of preoperative statin therapy on postoperative complications and mortality in a large group of patients undergoing valve surgery. PATIENTS, MATERIALS, AND METHODS: The data of consecutive patients undergoing isolated valve replacement during an 8-year period were retrospectively reviewed from a prospective database. Mortality was compared between the patients who received preoperative statin (statin group [SG]) and those who did not receive statin (control group [CG]) after adjustment on EuroSCORE. Main postoperative complications and mortality were compared between the 2 groups by using a propensity score analysis. RESULTS: During the study period, 1115 patients were prospectively included, 796 in the CG group and 319 in the SG. The SG patients were significantly older, had more cardiovascular risk factors (hypertension, diabetes, and weight) than the CG patients, and benefited from more elective surgery or aortic valve replacement. No difference in mortality was found between the groups: 4.4% in the SG and 4.5% in the CG, P = .95. Multivariate analysis also revealed no effect of statin on mortality, according to the type of surgery (aortic valve surgery alone or any kind of valve surgery) (P = .93), or the elective or urgent nature of the surgery (P = .67). Statin did not predict mortality after stratification with the EuroSCORE or the Parsonnet score. No difference was found between the 2 groups for postoperative complications (24-hour bleeding, atrial fibrillation, renal failure, length of mechanical ventilation, or hospital stay) and mortality after adjustment with a propensity score. DISCUSSION: This study found no difference in mortality or morbidity associated with preoperative statin therapy after isolated valve surgery.


Subject(s)
Cardiac Surgical Procedures/methods , Heart Valve Diseases/surgery , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Postoperative Complications/prevention & control , Preoperative Care/methods , Propensity Score , Aged , Female , Follow-Up Studies , France/epidemiology , Humans , Male , Morbidity/trends , Postoperative Complications/epidemiology , Retrospective Studies , Survival Rate/trends , Time Factors , Treatment Outcome
15.
J Biol Chem ; 292(24): 10153-10168, 2017 06 16.
Article in English | MEDLINE | ID: mdl-28476886

ABSTRACT

Alteration of ryanodine receptor (RyR)-mediated calcium (Ca2+) signaling has been reported in Alzheimer disease (AD) models. However, the molecular mechanisms underlying altered RyR-mediated intracellular Ca2+ release in AD remain to be fully elucidated. We report here that RyR2 undergoes post-translational modifications (phosphorylation, oxidation, and nitrosylation) in SH-SY5Y neuroblastoma cells expressing the ß-amyloid precursor protein (ßAPP) harboring the familial double Swedish mutations (APPswe). RyR2 macromolecular complex remodeling, characterized by depletion of the regulatory protein calstabin2, resulted in increased cytosolic Ca2+ levels and mitochondrial oxidative stress. We also report a functional interplay between amyloid ß (Aß), ß-adrenergic signaling, and altered Ca2+ signaling via leaky RyR2 channels. Thus, post-translational modifications of RyR occur downstream of Aß through a ß2-adrenergic signaling cascade that activates PKA. RyR2 remodeling in turn enhances ßAPP processing. Importantly, pharmacological stabilization of the binding of calstabin2 to RyR2 channels, which prevents Ca2+ leakage, or blocking the ß2-adrenergic signaling cascade reduced ßAPP processing and the production of Aß in APPswe-expressing SH-SY5Y cells. We conclude that targeting RyR-mediated Ca2+ leakage may be a therapeutic approach to treat AD.


Subject(s)
Amyloid beta-Peptides/metabolism , Calcium Signaling , Neurons/enzymology , Protein Processing, Post-Translational , Receptors, Adrenergic, beta-2/metabolism , Ryanodine Receptor Calcium Release Channel/metabolism , Adrenergic beta-2 Receptor Antagonists/pharmacology , Alzheimer Disease/enzymology , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/genetics , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Calcium Signaling/drug effects , Cell Line, Tumor , Cyclic AMP-Dependent Protein Kinases/chemistry , Cyclic AMP-Dependent Protein Kinases/metabolism , Enzyme Activation/drug effects , Humans , Mutation , Nerve Tissue Proteins/agonists , Nerve Tissue Proteins/chemistry , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neurons/drug effects , Neurons/metabolism , Neurons/pathology , Oxidation-Reduction , Oxidative Stress/drug effects , Phosphorylation/drug effects , Protein Multimerization/drug effects , Protein Processing, Post-Translational/drug effects , Proteolysis/drug effects , Receptors, Adrenergic, beta-2/chemistry , Receptors, Adrenergic, beta-2/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Ryanodine Receptor Calcium Release Channel/chemistry , Tacrolimus Binding Proteins/antagonists & inhibitors , Tacrolimus Binding Proteins/metabolism
16.
Glob Chang Biol ; 24(8): 3368-3389, 2018 08.
Article in English | MEDLINE | ID: mdl-29450980

ABSTRACT

Enteric methane (CH4 ) production from cattle contributes to global greenhouse gas emissions. Measurement of enteric CH4 is complex, expensive, and impractical at large scales; therefore, models are commonly used to predict CH4 production. However, building robust prediction models requires extensive data from animals under different management systems worldwide. The objectives of this study were to (1) collate a global database of enteric CH4 production from individual lactating dairy cattle; (2) determine the availability of key variables for predicting enteric CH4 production (g/day per cow), yield [g/kg dry matter intake (DMI)], and intensity (g/kg energy corrected milk) and their respective relationships; (3) develop intercontinental and regional models and cross-validate their performance; and (4) assess the trade-off between availability of on-farm inputs and CH4 prediction accuracy. The intercontinental database covered Europe (EU), the United States (US), and Australia (AU). A sequential approach was taken by incrementally adding key variables to develop models with increasing complexity. Methane emissions were predicted by fitting linear mixed models. Within model categories, an intercontinental model with the most available independent variables performed best with root mean square prediction error (RMSPE) as a percentage of mean observed value of 16.6%, 14.7%, and 19.8% for intercontinental, EU, and United States regions, respectively. Less complex models requiring only DMI had predictive ability comparable to complex models. Enteric CH4 production, yield, and intensity prediction models developed on an intercontinental basis had similar performance across regions, however, intercepts and slopes were different with implications for prediction. Revised CH4 emission conversion factors for specific regions are required to improve CH4 production estimates in national inventories. In conclusion, information on DMI is required for good prediction, and other factors such as dietary neutral detergent fiber (NDF) concentration, improve the prediction. For enteric CH4 yield and intensity prediction, information on milk yield and composition is required for better estimation.


Subject(s)
Agriculture/methods , Cattle/physiology , Methane/analysis , Milk/statistics & numerical data , Animals , Australia , Databases, Factual , Eating , Europe , European Union , Female , Lactation , Methane/metabolism , Milk/metabolism , Models, Theoretical , United States
17.
Blood ; 123(9): 1372-83, 2014 Feb 27.
Article in English | MEDLINE | ID: mdl-24398328

ABSTRACT

The main molecular basis of essential thrombocythemia and hereditary thrombocytosis is acquired, and germ-line-activating mutations affect the thrombopoietin signaling axis. We have identified 2 families with hereditary thrombocytosis presenting novel heterozygous germ-line mutations of JAK2. One family carries the JAK2 R867Q mutation located in the kinase domain, whereas the other presents 2 JAK2 mutations, S755R/R938Q, located in cis in both the pseudokinase and kinase domains. Expression of Janus kinase 2 (JAK2) R867Q and S755R/R938Q induced spontaneous growth of Ba/F3-thrombopoietin receptor (MPL) but not of Ba/F3-human receptor of erythropoietin cells. Interestingly, both Ba/F3-MPL cells expressing the mutants and platelets from patients displayed thrombopoietin-independent phosphorylation of signal transducer and activator of transcription 1. The JAK2 R867Q and S755R/R938Q proteins had significantly longer half-lives compared with JAK2 V617F. The longer half-lives correlated with increased binding to the heat shock protein 90 (HSP90) chaperone and with higher MPL cell-surface expression. Moreover, these mutants were less sensitive to JAK2 and HSP90 inhibitors than JAK2 V617F. Our results suggest that the mutations in the kinase domain of JAK2 may confer a weak activation of signaling specifically dependent on MPL while inducing a decreased sensitivity to clinically available JAK2 inhibitors.


Subject(s)
Drug Resistance/genetics , Germ-Line Mutation , Janus Kinase 2/genetics , Protein Kinase Inhibitors/therapeutic use , Thrombocytosis/drug therapy , Thrombocytosis/genetics , Adolescent , Adult , Aged , Animals , Cells, Cultured , Female , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Humans , Janus Kinase 2/antagonists & inhibitors , Janus Kinase 2/chemistry , Male , Mice , Middle Aged , Pedigree , Protein Structure, Tertiary/genetics , Young Adult
18.
JCI Insight ; 9(11)2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38855865

ABSTRACT

Monogenic diabetes is a gateway to precision medicine through molecular mechanistic insight. Hepatocyte nuclear factor 1A (HNF-1A) and HNF-4A are transcription factors that engage in crossregulatory gene transcription networks to maintain glucose-stimulated insulin secretion in pancreatic ß cells. Variants in the HNF1A and HNF4A genes are associated with maturity-onset diabetes of the young (MODY). Here, we explored 4 variants in the P2-HNF4A promoter region: 3 in the HNF-1A binding site and 1 close to the site, which were identified in 63 individuals from 21 families of different MODY disease registries across Europe. Our goal was to study the disease causality for these variants and to investigate diabetes mechanisms on the molecular level. We solved a crystal structure of HNF-1A bound to the P2-HNF4A promoter and established a set of techniques to probe HNF-1A binding and transcriptional activity toward different promoter variants. We used isothermal titration calorimetry, biolayer interferometry, x-ray crystallography, and transactivation assays, which revealed changes in HNF-1A binding or transcriptional activities for all 4 P2-HNF4A variants. Our results suggest distinct disease mechanisms of the promoter variants, which can be correlated with clinical phenotype, such as age of diagnosis of diabetes, and be important tools for clinical utility in precision medicine.


Subject(s)
Diabetes Mellitus, Type 2 , Hepatocyte Nuclear Factor 1-alpha , Hepatocyte Nuclear Factor 4 , Promoter Regions, Genetic , Hepatocyte Nuclear Factor 4/genetics , Hepatocyte Nuclear Factor 4/metabolism , Humans , Hepatocyte Nuclear Factor 1-alpha/genetics , Hepatocyte Nuclear Factor 1-alpha/metabolism , Promoter Regions, Genetic/genetics , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Gene Expression Regulation , Binding Sites , Crystallography, X-Ray , Male , Female , Protein Binding
19.
Hum Mutat ; 34(5): 669-85, 2013 May.
Article in English | MEDLINE | ID: mdl-23348805

ABSTRACT

Maturity-onset diabetes of the young (MODY) is a monogenic disorder characterized by autosomal dominant inheritance of young-onset (typically <25 years), noninsulin-dependent diabetes due to defective insulin secretion. MODY is both clinically and genetically heterogeneous with mutations in at least 10 genes. Mutations in the HNF1A gene encoding hepatocyte nuclear factor-1 alpha are the most common cause of MODY in most adult populations studied. The number of different pathogenic HNF1A mutations totals 414 in 1,247 families. Mutations in the HNF4A gene encoding hepatocyte nuclear factor-4 alpha are a rarer cause of MODY with 103 different mutations reported in 173 families to date. Sensitivity to treatment with sulfonylurea tablets is a feature of both HNF1A and HNF4A mutations. The HNF4A MODY phenotype has been expanded by the reports of macrosomia in ∼50% of babies, and more rarely, neonatal hyperinsulinemic hypoglycemia. The identification of an HNF1A or HNF4A gene mutation has important implications for clinical management in diabetes and pregnancy, but MODY is significantly underdiagnosed. Current research is focused on identifying biomarkers and developing probability models to identify those patients most likely to have MODY, until next generation sequencing technology enables cost-effective gene analysis for all patients with young onset diabetes.


Subject(s)
Diabetes Mellitus, Type 2/genetics , Hepatocyte Nuclear Factor 1-alpha/genetics , Hepatocyte Nuclear Factor 4/genetics , Hyperinsulinism/genetics , Hypoglycemia/genetics , Mutation , Animals , Base Sequence , Chromosome Aberrations , CpG Islands , DNA Primers , Disease Models, Animal , Humans , Polymorphism, Genetic
20.
J Minim Invasive Gynecol ; 20(5): 573-82, 2013.
Article in English | MEDLINE | ID: mdl-23759693

ABSTRACT

STUDY OBJECTIVE: To assess recurrence and pregnancy rates in women with ovarian endometrioma treated via ablation using plasma energy. DESIGN: Retrospective non-comparative pilot study including 55 patients treated during 28 months, with prospective recording of data (Canadian Task Force classification II-2). SETTING: Tertiary referral center. PATIENTS: Fifty-five consecutive women with pelvic endometriosis in whom ovarian endometriomas were managed solely via ablation using plasma energy. The minimum follow-up was 1 year. INTERVENTION: Endometrioma ablation using plasma energy. MEASUREMENTS AND MAIN RESULTS: Information was obtained from the database of the North-West Inter Regional Female Cohort for Patients with Endometriosis, based on self-questionnaires completed before surgery, surgical and histologic data, and systematic recording of recurrences, pregnancy, and symptoms. Recurrences were assessed using pelvic ultrasound examination. Mean (SD) follow-up was 20.6 (7.2) months (range, 12-39 months). In 75% of patients, deep infiltrating endometriosis was treated, and 40% had colorectal involvement. Preoperative infertility was recorded in 42% of patients. The rate of postoperative recurrence was 10.9% for the entire series. Of 33 women who wished to conceive, 67% became pregnant, spontaneously in 59%. Time from surgery to the first pregnancy was 7.6 (4.3) months. After discontinuation of postoperative hormone therapy, the probability of not conceiving at 12 months was 0.36 (95% confidence interval, 0.19-0.53), and at 24 months was 0.27 (95% confidence interval, 0.12-0.44). CONCLUSIONS: Recurrence and pregnancy rates are encouraging in that they seem comparable to the best reported results after endometrioma cystectomy. Plasma energy may have an important role in the management of ovarian endometrioma in women seeking to conceive. Patients most in need of surgical procedures that can spare ovarian parenchyma, such as those with bilateral endometriomas or a history of ovarian surgery, may particularly benefit from ablation using plasma energy.


Subject(s)
Endometrial Ablation Techniques/methods , Endometriosis/surgery , Fertility/physiology , Ovarian Diseases/surgery , Ovary/surgery , Adult , Female , Humans , Pilot Projects , Postoperative Period , Pregnancy , Pregnancy Rate , Retrospective Studies , Treatment Outcome
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