1,408 research outputs found
The effects of cannabis use during pregnancy on low birth weight and preterm birth: A systematic review and meta-analysis
Objective: to summarize literature regarding the effects of cannabis use during pregnancy on low birthweight (LBW), preterm birth (PTB) and small for gestational age (SGA). Study Design: systematic review and meta-analysis. A literature search was conducted in PubMed, Scopus, EBSCO and Web of Science in May 2021 and updated in November 2021. Only studies that assessed the isolated use of cannabis during pregnancy, controlling for cigarette smoking and other illicit drug use, were included. Data was synthesized using a narrative summary and pooled adjusted estimates and 95% confidence intervals (CI) were calculated for each outcome. Data was analyzed using Stata 13.0 with METAN software package, using random effects. Statistical heterogeneity was assessed using the Cochran's Q and Higgins I2 tests. Results: 32 studies were included with data from approximately 5.5 million women for the LBW outcome and 23 million for the PTB and SGA outcomes. Pregnant women using cannabis are at increased risk for LBW (aOR= 1.52; 95%CI= [1.18;1.96]), PTB (aOR= 1.39; 95%CI= [1.28;1.51]), and SGA (aOR= 1.47; 95%CI= [1.38;1.58]). Studies that assessed type of preterm birth and gestational age at birth indicate higher risks of spontaneous PTB and of early or very-early preterm births associated with cannabis use during pregnancy. The few studies that assessed the timing and frequency of consumption suggest a dose-response effect, with higher odds of negative outcomes among women who reported heavy use and with continued use during the second and third trimester of gestation. Conclusion: There is an effect of cannabis irrespectively of other illicit drugs and tobacco, despite high heterogeneity and low quality of evidence. There is a need to discuss public policies regarding cannabis' regulation and how it influences its consumption. Future studies should focus on the effects of cannabis's type (medicinal or recreational), timing and dosage during pregnancy on perinatal outcomes. © 2022 Thieme Medical Publishers, Inc.. All rights reserved.This review was performed within the scope of the project “The Importance of the Right Weight at Birth” funded by the Calouste Gulbenkian Foundation
Endometrial polyps in postmenopausal women
The malignancy risk of endometrial polyps in postmenopausal women was correlated with the presence or absence of abnormal uterine bleeding. Of 481 postmenopausal women who presented with endometrial polyps at diagnostic hysteroscopy between 2004 and 2007, 48.9% were asymptomatic and 51.1% had postmenopausal uterine bleeding. Transvaginal ultrasound revealed abnormal endometrial thickness in 60.0% vs. 57.7%, polyps in 37.9% vs. 32.9%, endometrial tumors in 1.3% vs. 0.8%, and submucosal myomas in 0.9% vs. 2.0% by the absence or presence of bleeding. Around three-fourth of the polyps were removed. Histopathologic diagnoses showed mucous polyps in 93.7 of asymptomatic women compared to 80.7% of those with bleeding, while endometrial tumors were only seen in those bleeding (7.2%). The malignancy risk within endometrial polyps in postmenopausal women varies with the presence of vaginal bleeding, and is minimal in asymptomatic women
An open and parallel multiresolution framework using block-based adaptive grids
A numerical approach for solving evolutionary partial differential equations
in two and three space dimensions on block-based adaptive grids is presented.
The numerical discretization is based on high-order, central finite-differences
and explicit time integration. Grid refinement and coarsening are triggered by
multiresolution analysis, i.e. thresholding of wavelet coefficients, which
allow controlling the precision of the adaptive approximation of the solution
with respect to uniform grid computations. The implementation of the scheme is
fully parallel using MPI with a hybrid data structure. Load balancing relies on
space filling curves techniques. Validation tests for 2D advection equations
allow to assess the precision and performance of the developed code.
Computations of the compressible Navier-Stokes equations for a temporally
developing 2D mixing layer illustrate the properties of the code for nonlinear
multi-scale problems. The code is open source
Revealing new biotechnological potentialities of the riboflavin producer fungus Ashbya gossypii by means of the construction and analysis of its metabolic network
Extensive intracranial involvement with multiple dissections in a case of giant cell arteritis
A 56-year-old man presented with weight loss, articular pain and minor neurological symptoms progressing over 1 month. Neurosonological evaluation suggested occlusion in intracranial segments of the left vertebral artery (VA) and of both internal carotid arteries (ICA) and hypoechoic halo sign in both superficial temporal arteries. The diagnosis of giant cell arteritis was supported by inflammatory markers and confirmed by biopsy. Despite early steroid initiation, he manifested fluctuant vascular deficits and became lethargic. Brain MRI indicated watershed infarcts and intracranial dissections of left VA and both ICA. The patient was stabilised with the association of prednisolone 2 mg/kg, methotrexate and oral anticoagulation. Since then he has been neurologically asymptomatic and control imaging showed only residual intracranial left VA stenosis, with no signs of temporal artery inflammation or new vascular lesions. This is to the best of our knowledge, the first reported clinical case with such an extensive intracranial involvement with multiple dissections
Physiological characterization and promoter engineering of Acetobacterium wieringae for acetone production via gas fermentation
The pressing need to mitigate environmental concerns has driven research into sustainable energy
and chemical production methods that reduce carbon emissions. Gas fermentation offers a promising
avenue for low-carbon fuel and chemical synthesis. Acetobacterium wieringae, particularly strain A.
wieringae JM, has emerged as an attractive host for gas-based biorefineries due to its unique
abilities, including growth in diverse gas compositions and pH ranges, and efficient growth on
carbon monoxide without co-substrates.
This study focuses on enhancing the potential of A. wieringae for acetone production through
genetic modification. A transformation protocol was developed, and the acetone production operon
from Clostridium acetobutylicum was introduced. Novel promoters were explored to widen gene
expression possibilities in A. wieringae. The stability of the plasmid backbone pMTL83151 carrying
replicon pCB102 was assessed. Additionally, the tolerance of A. wieringae to gas synthesis derived
from biogenic residue gasification was evaluated for potential industrial application.
Gas composition significantly influenced acetone production by A. wieringae, with distinct
physiological effects observed between strain A. wieringae DSM 1911 and
A. wieringae JM. Four constitutive promoters from A. wieringae JM and four from C.
autoethanogenum were successfully expressed, exhibiting stronger activity than the reference Pthl
promoter from C. acetobutylicum. Notably, A. wieringae JM demonstrated robust growth in synthesis
gas from biomass gasification, though with physiological variations.
This study unveils the intricate relationship between gas composition, physiological attributes, and
acetone production in A. wieringae. The expanded promoter repertoire enhances genetic
manipulation potential, propelling the strain's capacity for versatile gene expression. Moreover, the
resilience of A. wieringae JM to gasification-derived gas synthesis highlights its viability for
industrial implementation. These findings contribute to advancing the development of gas-based
biorefineries, paving the way for sustainable chemical production with reduced environmental impact.info:eu-repo/semantics/publishedVersio
Reconstruction of a genome-scale metabolic model for the riboflavin producer fungus Ashbya gossypii
Metabolic models are an important tool for in silico simulation of cells’ behavior. Until now, a considerable number of metabolic models have been released for a wide range of microorganisms.
Ashbya gossypii is an industrial-relevant fungus intensively used for riboflavin production with no model reported until now. Despite its high similarity with Saccharomyces cerevisiae genome, A. gossypii contains only 4726 protein-coding genes and, contrarily to S. cerevisiae, has a filamentous growth. Here, we describe the first genome-scale metabolic reconstruction for Ashbya gossypii.
Initially the whole genome was functionally re-annotated and each metabolic gene was assigned to an EC number using several databases such as UniProt, SGD, AGD, ExPASy and BRENDA. A total of 1429 genes were assigned to the different enzymatic families: 35.4 % hydrolases; 35.8 % transferases; 28.8 % other enzymatic families. Of the 1429 genes, 59 were assigned to multiple EC numbers and among these 36 % had EC numbers from different enzymatic families.
The next step of the reconstruction was the elaboration of the reactions set. Re-annotation data was crossed with the curated models iMM904 and iIN800 from S. cerevisiae. Some databases like BRENDA, KEGG or Metacyc were used in the cases where data were not available and an in-house tool was used to predict the transport reactions from A. gossypii genome sequences. At the end of this step, a set with 1755 reactions and 926 metabolites was obtained.
Using the obtained set of reactions the metabolic network was analyzed for possible gaps. All the gaps were filled by adding specific reactions leading to a model able to predict cell growth.
Current efforts aim model’s validation against experimental data in order to allow more accurate predictions of cell’s phenotype. More specifically, it is expected a final model able to provide valuable genetic strategies that could lead to significant improvements on A. gossypii as a cell factory
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