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1.
Heliyon ; 9(10): e20044, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37767512

ABSTRACT

As the construction industry moves towards greater sustainability, the application of more durable and environmentally friendly materials, capable of providing comfort in buildings and infrastructure, is a key element to consider. In this context, the use of alkali-activated binders (AAB) and geopolymers (GP), which have a lower carbon footprint than ordinary Portland cement (OPC), has emerged as an important alternative. Moreover, the addition of waste-based lightweight aggregates (LWA) to AAB and GP matrices produces lightweight composites that offer enhanced mechanical performance and improved comfort as building materials, while offering an alternative use to the increasing number of waste materials from diverse sources. This paper presents a comprehensive review of the literature on the above-mentioned topics (waste LWA in an AAB/GP matrix) published between 2012 and 2023, mainly indexed in the Scopus database. The waste-based LWA reported in the literature were categorized, and their properties and morphology presented. Then, the influence of the size, quantity, and nature of the LWA on the composite's properties and performance was analyzed. Fresh state performance, mechanical performance, density, and thermal and acoustic insulation were considered. This review is complemented by a bibliometric analysis, where keyword correlation and co-authorship networks on this field are established. The review highlights the potential of cementitious composites including waste-based LWA as a sustainable building material for structural and non-structural applications. However, more studies are required to further understand the behaviour of these composites under innovative manufacturing processes, such as extrusion and 3D printing.

2.
BAG, J. basic appl. genet. (Online) ; 31(2): 12-25, Dec. 2020. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1345377

ABSTRACT

ABSTRACT Dynorphin A is an endogenous opioid peptide that is part of the KNDy system in the hypothalamus of mammals. This peptide acts as an inhibitor of the GnRH pulse generation, thus regulating the onset of puberty and reproductive cycles. The PDYN gene encodes the propeptide Prodynorphin, the precursor of Dynorphin A. Despite its physiological relevance, PDYN has not emerged as a candidate gene associated with puberty in genomic association studies conducted in cattle. The present work aimed to search for signatures of selection on the PDYN gene among cattle breeds. To this, the whole genome sequences from 57 samples of ten cattle breeds were used. The samples were grouped based on breed selection history and their productive differences, particularly in terms of sexual precocity. The population structure was analyzed using Principal Component Analyses. To evidence recent selection processes, neutrality tests, such as Tajima's D and Fu & Li's F* and D* were performed in defined functional regions of PDYN. The putative promoter of PDYN showed a population structure that is in agreement with the criteria considered to make the groups. In that region, neutrality tests were consistently negative and resulted in statistically significant for the dairy breeds. Also, these breeds exhibited less variability in the haplotype analyses than the others. The results presented here suggest that regulatory regions of PDYN could be under positive selection, particularly in dairy breeds.


RESUMEN Dinorfina A es un péptido opioide endógeno que forma parte del sistema KNDy en el hipotálamo de mamíferos. Este péptido actúa como inhibidor de la generación de los pulsos de GnRH, regulando así el inicio de la pubertad y los ciclos reproductivos. El gen PDYN codifica el propéptido Prodinorfina, precursor de Dinorfina A. A pesar de su relevancia fisiológica, PDYN no ha surgido como gen candidato asociado a pubertad en estudios de asociación genómicos en bovinos. El presente trabajo tuvo como objetivo buscar huellas de selección en el gen PDYN entre diferentes razas bovinas. Para alcanzarlo se utilizaron secuencias genómicas de 57 muestras de diez razas bovinas. Las muestras fueron agrupadas considerando la historia de selección y las diferencias productivas entre razas, particularmente en términos de precocidad sexual. La estructura poblacional fue analizada usando análisis de componentes principales. Para evidenciar procesos de selección recientes se realizaron pruebas de neutralidad, tales como D de Tajima y F* y D* de Fu & Li, en diferentes regiones funcionales de PDYN. El promotor putativo de PDYN mostró una estructura poblacional que es consistente con los criterios usados para agrupar las razas. En esa región, las pruebas de neutralidad fueron consistentemente negativas y estadísticamente significativas en las razas lecheras. Además, estas razas también exhibieron menor variabilidad en los análisis de haplotipos que las demás razas. Los resultados presentados aquí sugieren que regiones regulatorias de PDYN estarían bajo selección positiva, particularmente en razas bovinas lecheras.

3.
Anim Genet ; 48(4): 377-385, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28568840

ABSTRACT

The 70 kilodalton heat shock proteins (Hsp70) are highly conserved molecular chaperones which have a crucial role in the stress response of the cell. In mammals, the Hsp70 proteins are encoded by a cluster of three genes: HSPA1A, HSPA1B and HSPA1L. In bovines, this cluster is located on chromosome 23 downstream of the major histocompatibility complex (BoLA). We detected inconsistencies in the location of markers on the Hsp70 genes reported in the literature that pointed to a potential deletion in the bovine reference genome UMD 3.1.1. An in silico analysis of the bovine genomic region of the Hsp70 cluster, using available information from public databases, confirmed the existence of a deletion of 11.1-kb spanning the HSPA1B gene and the intergenic region between HSPA1B and HSPA1A. Although we originally considered this an assembly error, it is most likely a particular condition of L1 Dominette 01449, the cow sequenced in the Bovine Genome Project. Moreover, we suggest a new classification of bovine Hsp70 sequences reported in NCBI and a reassignment of the location of SNPs from dbSNP that map to the deletion on BTA23. We also compared the location of selected transcription factor binding sites on the promoters of HSPA1A and HSPA1B. The results generated in the present work could be helpful to refine the reference genome of an important livestock species and also to understand the role and the regulation of the bovine Hsp70 genes.


Subject(s)
Cattle/genetics , HSP70 Heat-Shock Proteins/genetics , Sequence Deletion , Animals , Binding Sites , DNA, Intergenic , Genome , Multigene Family , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Sequence Analysis, DNA
4.
Sex Transm Infect ; 85(2): 82-7, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18987014

ABSTRACT

OBJECTIVE: The potential adverse effects of antiretroviral drugs during pregnancy are discrepant and few studies, mostly from Europe, have provided information about pregnancy outcomes of those already on treatment at conception. The aim of this study was to investigate the impact of antiretrovirals (ARVs) on pregnancy outcome according to the timing of treatment initiation in a cohort of pregnant women from Brazil infected with HIV. METHODS: A prospective cohort of 696 pregnant women followed up in one single centre between 1996 and 2006 was studied. Patients who had ARV treatment before pregnancy were compared with those treated after the first trimester. The outcomes evaluated were preterm delivery (PTD) (<37 weeks), severe PTD (<34 weeks), low birth weight (LBW) (<2500 g) and very LBW (<1500 g). RESULTS: Patients who were using ARVs pre-conception had higher rates of LBW (33.3% vs 16.5%; p<0.001) and a similar trend for PTD (26.3% vs 17.7%; p = 0.09). Stratification by type of therapy (dual vs highly active antiretroviral therapy (HAART)) according to timing of initiation of ARVs showed that patients who use HAART pre-conception have a higher rate of PTD (20.2% vs 10.2%; p = 0.03) and LBW (24.2% vs 10.2%; p = 0.002). After adjusting for several factors, HAART used pre-conception was associated with an increased risk for PTD (AOR 5.0; 95% CI 1.5 to 17.0; p = 0.009) and LBW (OR 3.6; 95% CI 1.7 to 7.7; p = 0.001). CONCLUSIONS: We identified an increased risk for LBW and PTD in patients who had HAART prior to pregnancy.


Subject(s)
Anti-HIV Agents/adverse effects , Antiretroviral Therapy, Highly Active/adverse effects , HIV Infections/drug therapy , HIV-1 , Pregnancy Complications, Infectious/drug therapy , Adult , Brazil , Female , HIV Infections/complications , Humans , Infant, Low Birth Weight , Infant, Newborn , Infant, Premature , Infant, Very Low Birth Weight , Pregnancy , Pregnancy Outcome , Premature Birth/chemically induced , Prospective Studies , Risk Factors , Young Adult
5.
Am J Trop Med Hyg ; 57(3): 309-12, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9311641

ABSTRACT

In Mexico cutaneous leishmaniasis (CL) occurs in 17 of 32 States, and is a serious public health problem. This is a report of treatment of CL patients in the State of Tabasco, Mexico with a localized current field-radio frequency (LCF-RF) device to generate precisely controlled heat as an alternative to prohibitively expensive drug treatment. It was not a controlled clinical trial, but rather an evaluation of the feasibility of this form of treatment for all CL patients encountered in the endemic area. A total of 201 previously diagnosed patients with CL caused by Leishmania mexicana were treated with a portable Thermosurgery LCF-RF generator powered by rechargeable batteries. The ages of the patients ranged from two to 75 years; the sex distribution was 63% males and 37% females. A single device was used in five different municipalities. Lesions were first anesthetized with 1% lidocaine HCl and moistened with normal saline solution. Treatment consisted of a single application that produced 50 degrees C for 30 sec. After four weeks, 122 patients were available for evaluation, of which 95% were totally cured; (even those involving ear cartilage, which respond poorly to antimonials). At eight weeks post-treatment, 191 patients were evaluated, with a total cure rate of 90%. This form of treatment proved to be effective and convenient for use in primary health care facilities in Mexico and has many advantages over traditional forms of therapy.


Subject(s)
Hot Temperature/therapeutic use , Leishmaniasis, Cutaneous/therapy , Radiofrequency Therapy , Adolescent , Adult , Aged , Child , Child, Preschool , Feasibility Studies , Female , Humans , Male , Mexico , Middle Aged , Sex Distribution , Treatment Outcome
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