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The study is to evaluate the total sediment transport (suspended and bed load) in a Mediterranean river (Bellah, Tipaza, Algeria). To understand this study, we based our analysis on hydrometric data related to the instantaneous discharge and to the concentration of suspended sediment, over a period of 33 years (from 1974/75 to 2006/07). The results show that a good correlation between the suspended sediments and water discharge. The exponent b of our model is equal to 1.38, a value close to those found by researchers who worked in semi-arid region. The suspended sediment transport is about 610 t km-2 year-1. This value is comparable to those found in other regions with similar hydrologic regimes. The bed load is about 170 t km-2 year-1 for τ0 = γ × I × Rh t km-2 year-1 and it is about 115 t km-2 year-1 for τ0 = 0.7×γ × I × Rh. The total sediment transport is estimated at 725 t km-2 year-1 if we take into account the corrective coefficient of roughness in the bed of the wadi and equal to 780 t km-2 year-1 in other direction. To better judge our results, we compared them with those obtained by the relationship Tixeront which remains the most used for estimating the specific degradation in the basins of the Maghreb. The value obtained by the relation of Tixeront is slightly below our own values, but it is permissible to say that the results are of the same order of magnitude. This slight difference can be explained by the introduction of the amount of sediments carried in the determination of the specific erosion of the watershed rates. [ABSTRACT FROM AUTHOR]

The Seklafa catchment, with an area of 787 km², which is part of the Jebel Amour region (Algeria), is characterized by a spatio-temporal irregularity of the rains, a gap fairly high thermal, a deteriorated marly lithology and weak and unsuitable vegetation cover, which makes it subject to severe erosion in all its forms. It was therefore the subject of an assessment of erosive states and of the various causal factors of the soil risk erosion by the adaptation of crossed matrices on the basis of the PAP / RAC directives. The three constituent approaches (predictive, descriptive and interactive) are analyzed and mapped by GIS and remote sensing. The predictive approach shows that 28.1% of interest region area has high and very high erodibility. The PCA shows a linear and positive correlation with their causal factors such as; the erodibility (r = 0.799), the slope (r = 0.663), the protection of soil (r = 0.487) and the rocks hardness (r = 0.414). This may mean that these variables better explain erosive states. The descriptive approach showed that, sheet erosion and gully erosion are the most apparent processes in the study area, covering 45.2% and 19.7% respectively. The interactive phase highlighted the overall trends in the surface evolution of the watershed. In view of these results, the use of PAP / RAC in a GIS environment has many advantages, notably those linked to the large number of results. [ABSTRACT FROM AUTHOR]

Due to their efficiency, revitalized traditional techniques for irrigation management of scarce water resources have been suggested as a way to at least partially cope with the present water crises in the Middle East. A better irrigation management includes re-using treated wastewater in agriculture. Treated wastewater should also be used in industrial processes, thus contributing to a more efficient overall water management. However, the most important change leading to better water management is improving water efficiency in agricultural irrigation. Traditional water management techniques have an important role in many Middle East and North African (MENA) countries. Besides bringing more water to a thirsty population, they can also contribute to the societal awareness, and recognition of the great diversity of cultural and social values water has to human civilization.EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR P. Hubert [ABSTRACT FROM PUBLISHER]

We report on the use of Laser Induced Breakdown Spectroscopy (LIBS) for determining presence of metals in landfill leachate samples from the Delaware Solid Waste Authority's (DSWA) Sandtown, Delaware landfill. A Q switched Nd:YAG laser along with spectrometer, detector and fiber optics cables were used for analyzing the leachate samples. Presence of each metal in the leachate samples has been uniquely identified from the LIBS emission lines associated with each element. The metals detected in the leachate samples include Al, Ba, Ca, Co, Cr, Fe, Li, Mg, Mn, K, Na, Sr, and Zn. The LIBS results were also compared to results obtained by Induc-tively Coupled Plasma Mass Spectroscopy (Method SW846 6010C). The results show that LIBS can be an inexpensive and attractive analytical technique for environmental monitoring and analysis. [ABSTRACT FROM AUTHOR]

Type 2 Diabetes Mellitus (T2DM), one of the most common metabolic disorders, is caused by a combination of two primary factors: defective insulin secretion by pancreatic β-cells and the inability of insulin-sensitive tissues to respond appropriately to insulin. Because insulin release and activity are essential processes for glucose homeostasis, the molecular mechanisms involved in the synthesis and release of insulin, as well as in its detection are tightly regulated. Defects in any of the mechanisms involved in these processes can lead to a metabolic imbalance responsible for the development of the disease. This review analyzes the key aspects of T2DM, as well as the molecular mechanisms and pathways implicated in insulin metabolism leading to T2DM and insulin resistance. For that purpose, we summarize the data gathered up until now, focusing especially on insulin synthesis, insulin release, insulin sensing and on the downstream effects on individual insulin-sensitive organs. The review also covers the pathological conditions perpetuating T2DM such as nutritional factors, physical activity, gut dysbiosis and metabolic memory. Additionally, because T2DM is associated with accelerated atherosclerosis development, we review here some of the molecular mechanisms that link T2DM and insulin resistance (IR) as well as cardiovascular risk as one of the most important complications in T2DM.

Peptide hormones and neuropeptides encompass a large class of bioactive peptides that regulate physiological processes like anxiety, blood glucose, appetite, inflammation and blood pressure. Here, we execute a focused discovery strategy to provide an extensive map of O-glycans on peptide hormones. We find that almost one third of the 279 classified peptide hormones carry O-glycans. Many of the identified O-glycosites are conserved and are predicted to serve roles in proprotein processing, receptor interaction, biodistribution and biostability. We demonstrate that O-glycans positioned within the receptor binding motifs of members of the neuropeptide Y and glucagon families modulate receptor activation properties and substantially extend peptide half-lives. Our study highlights the importance of O-glycosylation in the biology of peptide hormones, and our map of O-glycosites in this large class of biomolecules serves as a discovery platform for an important class of molecules with potential opportunities for drug designs.

Statins are the gold-standard treatment for the prevention of primary and secondary cardiovascular disease, which is the leading cause of mortality worldwide. Despite the safety and relative tolerability of statins, observational studies, clinical trials and meta-analyses indicate an increased risk of developing new-onset type 2 diabetes mellitus (T2DM) after long-term statin treatment. It has been shown that statins can impair insulin sensitivity and secretion by pancreatic β-cells and increase insulin resistance in peripheral tissues. The mechanisms involved in these processes include, among others, impaired Ca 2+ signaling in pancreatic β-cells, down-regulation of GLUT-4 in adipocytes and compromised insulin signaling. In addition, it has also been described that statins' impact on epigenetics may also contribute to statin-induced T2DM via differential expression of microRNAs. This review focuses on the evidence and mechanisms by which statin therapy is associated with the development of T2DM. This review describes the multifactorial combination of effects that most likely contributes to the diabetogenic effects of statins. Clinically, these findings should encourage clinicians to consider diabetes monitoring in patients receiving statin therapy in order to ensure early diagnosis and appropriate management.

The primary genetic cause of familial hypercholesterolemia (FH) is related to mutations in the LDLR gene encoding the Low-density Lipoprotein Receptor. LDLR structure is organized in 5 different domains, including an EGF-precursor homology domain that plays a pivotal role in lipoprotein release and receptor recycling. Mutations in this domain constitute 51.7% of the total missense variants described in LDLR. The aim of the present work was to analyse how clinically significant variants in the EGF-precursor homology domain impact LDLR. The activity of sixteen LDLR variants was functionally characterized by determining LDLR expression by Western blot and LDLR expression, LDL binding capacity and uptake, and LDLR recycling activity by flow cytometry in transfected CHO-ldlA7 cells. Of the analysed variants, we found six non-pathogenic LDLR variants and ten pathogenic variants distributed as follow: three class 3 variants; four class 2 variants; and three class 5 variants. These results can be incorporated into clinical management of patients by helping guide the appropriate level of treatment intensity depending on the extent of loss of LDLR activity. This data can also contribute to cascade-screening for pathogenic FH variants.

Background and Aims: Familial hypercholesterolemia (FH) is a monogenic disease characterized by high levels of low-density lipoprotein cholesterol and premature atherosclerotic cardiovascular disease. FH is caused by loss of function mutations in genes encoding LDL receptor (LDLR), and Apolipoprotein B (APOB) or gain of function (GOF) mutations in proprotein convertase subtilisin/kexin type 9 (PCSK9). In this study, we identified a novel variant in PCSK9, p.(Arg499His), located in the C-terminal domain, in two unrelated FH patients from Spain and Italy., Methods: We studied familial segregation and determined variant activity in vitro., Results: We determined PCSK9 expression, secretion and activity of the variant in transfected HEK293 cells; extracellular activity of the recombinant p.(Arg499His) PCSK9 variant in HEK 293 and HepG2 cells; PCSK9 affinity to the LDL receptor at neutral and acidic pH; the mechanism of action of the p.(Arg499His) PCSK9 variant by co-transfection with a soluble construct of the LDL receptor and by determining total PCSK9 intracellular accumulation when endosomal acidification is impaired and when an excess of soluble LDLr is present in the culture medium. Our results show high LDL-C concentrations and FH phenotype in p.(Arg499His) carriers. In vitro functional characterization shows that p.(Arg499His) PCSK9 variant causes a reduction in LDLr expression and LDL uptake. An intracellular activity for this variant is also shown when blocking the activity of secreted PCSK9 and by inhibiting endosomal acidification., Conclusions: We demonstrated that p.(Arg499His) PCSK9 variant causes a direct intracellular degradation of LDLr therefore causing FH by reducing LDLr availability., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Cholesterol is an essential component of cell barrier formation and signaling transduction involved in many essential physiologic processes. For this reason, cholesterol metabolism must be tightly controlled. Cell cholesterol is mainly acquired from two sources: Dietary cholesterol, which is absorbed in the intestine and, intracellularly synthesized cholesterol that is mainly synthesized in the liver. Once acquired, both are delivered to peripheral tissues in a lipoprotein dependent mechanism. Malfunctioning of cholesterol metabolism is caused by multiple hereditary diseases, including Familial Hypercholesterolemia, Sitosterolemia Type C and Niemann-Pick Type C1. Of these, familial hypercholesterolemia (FH) is a common inherited autosomal co-dominant disorder characterized by high plasma cholesterol levels. Its frequency is estimated to be 1:200 and, if untreated, increases the risk of premature cardiovascular disease. This review aims to summarize the current knowledge on cholesterol metabolism and the relation of FH to cholesterol homeostasis with special focus on the genetics, diagnosis and treatment.

Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by high blood-cholesterol levels mostly caused by mutations in the low-density lipoprotein receptor (LDLr). With a prevalence as high as 1/200 in some populations, genetic screening for pathogenic LDLr mutations is a cost-effective approach in families classified as 'definite' or 'probable' FH and can help to early diagnosis. However, with over 2000 LDLr variants identified, distinguishing pathogenic mutations from benign mutations is a long-standing challenge in the field. In 1998, the World Health Organization (WHO) highlighted the importance of improving the diagnosis and prognosis of FH patients thus, identifying LDLr pathogenic variants is a longstanding challenge to provide an accurate genetic diagnosis and personalized treatments. In recent years, accessible methodologies have been developed to assess LDLr activity in vitro, providing experimental reproducibility between laboratories all over the world that ensures rigorous analysis of all functional studies. In this review we present a broad spectrum of functionally characterized missense LDLr variants identified in patients with FH, which is mandatory for a definite diagnosis of FH., Competing Interests: The authors declare no conflict of interest.