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1.
J Endocrinol Invest ; 46(3): 567-576, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36242744

ABSTRACT

OBJECTIVE: Human brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut microbiota might be an efficient stimulus to activate BAT metabolism remains to be ascertained. We aimed to investigate the association of fecal microbiota composition with BAT volume and activity and mean radiodensity in young adults. METHODS: 82 young adults (58 women, 21.8 ± 2.2 years old) participated in this cross-sectional study. DNA was extracted from fecal samples and 16S rRNA sequencing was performed to analyse the fecal microbiota composition. BAT was determined via a static 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography scan (PET/CT) after a 2 h personalized cooling protocol. 18F-FDG uptake was also quantified in white adipose tissue (WAT) and skeletal muscles. RESULTS: The relative abundance of Akkermansia, Lachnospiraceae sp. and Ruminococcus genera was negatively correlated with BAT volume, BAT SUVmean and BAT SUVpeak (all rho ≤ - 0.232, P ≤ 0.027), whereas the relative abundance of Bifidobacterium genus was positively correlated with BAT SUVmean and BAT SUVpeak (all rho ≥ 0.262, P ≤ 0.012). On the other hand, the relative abundance of Sutterellaceae and Bifidobacteriaceae families was positively correlated with 18F-FDG uptake by WAT and skeletal muscles (all rho ≥ 0.213, P ≤ 0.042). All the analyses were adjusted for the PET/CT scan date as a proxy of seasonality. CONCLUSION: Our results suggest that fecal microbiota composition is involved in the regulation of BAT and glucose uptake by other tissues in young adults. Further studies are needed to confirm these findings. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov no. NCT02365129 (registered 18 February 2015).


Subject(s)
Microbiota , Positron Emission Tomography Computed Tomography , Adult , Female , Humans , Young Adult , Adipose Tissue, Brown/diagnostic imaging , Adipose Tissue, Brown/metabolism , Cross-Sectional Studies , Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography/methods , Positron-Emission Tomography , RNA, Ribosomal, 16S/genetics
2.
Rev Med Chil ; 151(6): 677-686, 2023 Jun.
Article in Spanish | MEDLINE | ID: mdl-38801375

ABSTRACT

BACKGROUND AND PURPOSE: Functional tests are a fundamental axis in assessing the risk of falls in older adults. However, many of them lack associative value with the actual functional status of the older adults, medical history, and comorbidities. METHODS: Analytical study with cross-sectional design. Three functional tests were performed (Timed Up & Go, Five Times Sit to Stand Test, and Unipodal Station Test) in 148 independent older adults (mean = 74.8 SD = 7.2), 83 non-fallers, and 58 with self-reported accidental falls in the last year. Other factors, such as grip strength and abdominal circumference, were considered. RESULTS AND DISCUSSION: The functional tests presented associative value in older adults with a history of falls (p < 0.05). The grip strength has a statistically significant correlation between both groups. Functional tests can discriminate the risk of falls in independent older adults and those with similar comorbidities. CONCLUSION: The three functional tests applied show associative values in falling older adults. The grip strength presented associative value with the functional tests.


Subject(s)
Accidental Falls , Geriatric Assessment , Hand Strength , Humans , Accidental Falls/statistics & numerical data , Cross-Sectional Studies , Aged , Male , Female , Hand Strength/physiology , Geriatric Assessment/methods , Aged, 80 and over , Risk Factors , Risk Assessment , Reference Values
3.
Rev Med Chil ; 149(9): 1302-1310, 2021 Sep.
Article in Spanish | MEDLINE | ID: mdl-35319683

ABSTRACT

BACKGROUND: Timed Up and Go (TUG) is used to assess the risk of falling of older people. AIM: To evaluate the sensitivity and specificity of TUG as a predictor of falls in older adults. MATERIAL AND METHODS: TUG was measured in 148 independent community-dwelling older adults aged 75 ± 7 years (85% women). Of these, 58 reported having a fall in the previous year. Analysis of the ROC (Receiver Operating Characteristic) curve was performed to assess the sensitivity and specificity of common cut-off times used in clinical practice. The times required to perform the TUG as quickly as possible (best fitted time) and at the usual pace (common time) were registered. RESULTS: Participants with a history of falls had higher TUG times than their counterparts who did not fall (10.9 ± 3.9 and 9.2 ± 2.6 s, respectively). By age groups, only in the 60-69 age group the differences between those who fell and those who did not, were statistically significant (p < 0.05). A cut-off of 9s generates the better sensitivity and specificity for the test (0.60 and 0.57, respectively). For 60-69 age group the best cut-off time is 8.2s, with an increase in sensitivity and specificity to 0.73 and 0.68, respectively. CONCLUSIONS: There were differences in TUG values between participants with and without a history of falls. Determining TUG cut-off values by age groups improves the sensitivity and specificity of the test, especially in the 60-69 age range.


Subject(s)
Accidental Falls , Aged , Aged, 80 and over , Female , Humans , Male , ROC Curve , Sensitivity and Specificity
4.
J Biol Chem ; 294(41): 15182-15192, 2019 10 11.
Article in English | MEDLINE | ID: mdl-31341016

ABSTRACT

Neurogenin-3 (NEUROG3) is a helix-loop-helix (HLH) transcription factor involved in the production of endocrine cells in the intestine and pancreas of humans and mice. However, the human NEUROG3 loss-of-function phenotype differs subtly from that in mice, but the reason for this difference remains poorly understood. Because NEUROG3 expression precedes exit of the cell cycle and the expression of endocrine cell markers during differentiation, we investigated the effect of lentivirus-mediated overexpression of the human NEUROG3 gene on the cell cycle of BON4 cells and various human nonendocrine cell lines. NEUROG3 overexpression induced a reversible cell cycle exit, whereas expression of a neuronal lineage homolog, NEUROG1, had no such effect. In endocrine lineage cells, the cellular quiescence induced by short-term NEUROG3 expression required cyclin-dependent kinase inhibitor 1A (CDKN1A)/p21CIP1 expression. Expression of endocrine differentiation markers required sustained NEUROG3 expression in the quiescent, but not in the senescent, state. Inhibition of the phosphatase and tensin homolog (PTEN) pathway reversed quiescence by inducing cyclin-dependent kinase 2 (CDK2) and reducing p21CIP1 and NEUROG3 protein levels in BON4 cells and human enteroids. We discovered that NEUROG3 expression stimulates expression of CDKN2a/p16INK4a and BMI1 proto-oncogene polycomb ring finger (BMI1), with the latter limiting expression of the former, delaying the onset of CDKN2a/p16INK4a -driven cellular senescence. Furthermore, NEUROG3 bound to the promoters of both CDKN1a/p21CIP1 and BMI1 genes, and BMI1 attenuated NEUROG3 binding to the CDKN1a/p21CIP1 promoter. Our findings reveal how human NEUROG3 integrates inputs from multiple signaling pathways and thereby mediates cell cycle exit at the onset of differentiation.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Cell Cycle Checkpoints , Mitogen-Activated Protein Kinase 7/metabolism , Nerve Tissue Proteins/metabolism , PTEN Phosphohydrolase/metabolism , Cell Line , Cellular Senescence , Gene Expression Regulation , Genes, p16 , Humans , Proto-Oncogene Mas
5.
Med Oral Patol Oral Cir Bucal ; 25(6): e791-e798, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-33037810

ABSTRACT

BACKGROUND: Oropharyngeal mucositis (OM) is one of the main side-effects of oncological therapy. There is no treatment to prevent its occurrence, but some zinc-based therapies have been proven to help in decreasing its intensity. The objective of this study was to determine the effect of zinc in OM in children with acute leukemia in the early stages of oncological treatment. MATERIAL AND METHODS: This quasi-experimental study evaluated OM in 2 groups (control group: conventional hospital management, and experimental group: administration of 50 mg of zinc gluconate daily plus conventional hospital management). OM severity was recorded at a two-month follow-up. RESULTS: Forty-nine patients (26 in the control group and 23 in the experimental group) were included. The mean age of the patients was 11.1 ± 2.7 years; 65.3% had a diagnosis of pre-B acute lymphoblastic leukemia. The incidences of OM in the control group and the experimental group were 46.2% and 26.1%, respectively, but the difference was not significant. Based on a negative binomial regression model, females had, on average, 1.5 more days with OM (p = 0.002), and patients assigned to the experimental group had, on average, 2 less days with OM than the control group (p = 0.001). The pain score was higher in the control group (p = 0.0009), as was the mean score on the WHO scale (p = 0.0012). CONCLUSIONS: Zinc facilitated a reduction in the severity and duration of OM; further studies focusing on children are needed to confirm the effects of this trace element.


Subject(s)
Antineoplastic Agents , Leukemia , Mucositis , Stomatitis , Adolescent , Antineoplastic Agents/adverse effects , Child , Female , Humans , Leukemia/drug therapy , Stomatitis/chemically induced , Stomatitis/drug therapy , Stomatitis/prevention & control , Zinc
6.
J Environ Manage ; 236: 309-316, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30738301

ABSTRACT

The aims of this work were to characterize the sorption and evaluate the inhibitory effect of octylphenol ethoxylate Triton X-100 (OPEOTx) on methanogenic and denitrifying sludges. According to Langmuir isotherm, maximums OPEOTx sorption values on methanogenic and denitrifying sludges were 60.70 mg (gVSS)-1 and 87.47 mg (gVSS)-1 respectively. The specific removal rate of chemical oxygen demand (rCOD) and the accumulated volume biogas (VBG) were used to evaluate the OPEOTx inhibitory effect on sludges. Experimental inhibition data were fitted to the models of non-competitive inhibition and modified Gompertz. Methanogenic sludges reached higher levels inhibition in the rCOD and biogas production potential Pmax (84.0 and 88.5%) comparing with denitrifying sludges (24.3 and 21.9%). Furthermore, in all OPEOTx concentrations, carbohydrates-proteins quotient value of the extracellular polymeric substances for the denitrifying sludges remained below respect to the same quotient in methanogenic sludges. The above contributes in part to explain the greater sorption capacity of the denitrifying sludges by OPEOTx and their granules resistance to be damaged by OPEOTx amphiphilic nature. The study gives insights to understand OPEOs interactions and their effects on methanogenic and denitrifying granular sludges.


Subject(s)
Phenols , Sewage , Bioreactors , Octoxynol
7.
Rev Med Chil ; 147(5): 668-672, 2019 May.
Article in Spanish | MEDLINE | ID: mdl-31859901

ABSTRACT

Autoimmune pancreatitis is uncommon, responds to steroids and is usually associated with diabetes mellitus. We report a 73 year-old male who, two months after a diagnosis of diabetes mellitus, presented with obstructive jaundice and weight loss. Abdominal magnetic resonance imaging was suggestive of an autoimmune pancreatitis and serum IgG4 was 339 mg/dl (normal range 3-201). The patient was treated with prednisone 40 mg/day with a good clinical and laboratory response. During outpatient care, the dose of prednisone was tapered.


Subject(s)
Autoimmune Pancreatitis/complications , Autoimmune Pancreatitis/drug therapy , Diabetes Complications , Diabetes Mellitus , Glucocorticoids/therapeutic use , Prednisone/therapeutic use , Aged , Autoimmune Pancreatitis/diagnostic imaging , Diabetes Complications/complications , Diabetes Complications/drug therapy , Diabetes Mellitus/drug therapy , Humans , Hypoglycemic Agents/therapeutic use , Immunoglobulin G/blood , Insulin/therapeutic use , Magnetic Resonance Imaging , Male , Treatment Outcome
8.
J Environ Manage ; 223: 1-8, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29883777

ABSTRACT

The abundance of fungi in a full-scale membrane bioreactor (MBR) treating urban wastewater and experiencing seasonal foaming was assessed by quantitative PCR (qPCR), comparing three different sets of widely used universal fungal primers targeting the gene encoding the small ribosomal subunit RNA, 18S-rDNA, (primers NS1-Fung and FungiQuant) or the internal transcribed spacer ITS2 (primers ITS3-ITS4). Fungi were a numerically important fraction of the MBR microbiota (≥106 18S-rDNA copies/L activated sludge), and occurred both in the aerated and anoxic bioreactors. The numbers of copies of fungal markers/L activated sludge calculated using the NS1-Fung or ITS3-ITS4 primer sets were up to 2 orders of magnitude higher than the quantifications based on the FungiQuant primers. Fungal 18S-rDNA counts derived from the FungiQuant primers decreased significantly during cold seasons, concurring with foaming episodes in the MBR. Redundancy analysis corroborated that temperature was the main factor driving fungi abundance, which was also favored by longer solid retention time (SRT), lower chemical oxygen demand/biochemical oxygen demand at 5 days (COD/BOD5) of influent water, and lower biomass accumulation in the MBR.


Subject(s)
Bioreactors , Wastewater , Membranes, Artificial , Polymerase Chain Reaction , Sewage , Waste Disposal, Fluid
9.
Appl Environ Microbiol ; 81(18): 6241-52, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26150458

ABSTRACT

In the present study, microbial toluene degradation in controlled constructed wetland model systems, planted fixed-bed reactors (PFRs), was queried with DNA-based methods in combination with stable isotope fractionation analysis and characterization of toluene-degrading microbial isolates. Two PFR replicates were operated with toluene as the sole external carbon and electron source for 2 years. The bulk redox conditions in these systems were hypoxic to anoxic. The autochthonous bacterial communities, as analyzed by Illumina sequencing of 16S rRNA gene amplicons, were mainly comprised of the families Xanthomonadaceae, Comamonadaceae, and Burkholderiaceae, plus Rhodospirillaceae in one of the PFR replicates. DNA microarray analyses of the catabolic potentials for aromatic compound degradation suggested the presence of the ring monooxygenation pathway in both systems, as well as the anaerobic toluene pathway in the PFR replicate with a high abundance of Rhodospirillaceae. The presence of catabolic genes encoding the ring monooxygenation pathway was verified by quantitative PCR analysis, utilizing the obtained toluene-degrading isolates as references. Stable isotope fractionation analysis showed low-level of carbon fractionation and only minimal hydrogen fractionation in both PFRs, which matches the fractionation signatures of monooxygenation and dioxygenation. In combination with the results of the DNA-based analyses, this suggests that toluene degradation occurs predominantly via ring monooxygenation in the PFRs.


Subject(s)
Environmental Microbiology , Environmental Pollutants/metabolism , Metabolic Networks and Pathways , Mixed Function Oxygenases/metabolism , Toluene/metabolism , Anaerobiosis , Bacteria/classification , Bacteria/genetics , Biota , Biotransformation , Carbon/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen/metabolism , Microarray Analysis , Molecular Sequence Data , Oxidation-Reduction , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Wetlands
10.
Gastroenterology ; 145(1): 138-148, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23562752

ABSTRACT

BACKGROUND & AIMS: Proprotein convertase 1/3 (PC1/3) deficiency, an autosomal-recessive disorder caused by rare mutations in the proprotein convertase subtilisin/kexin type 1 (PCSK1) gene, has been associated with obesity, severe malabsorptive diarrhea, and certain endocrine abnormalities. Common variants in PCSK1 also have been associated with obesity in heterozygotes in several population-based studies. PC1/3 is an endoprotease that processes many prohormones expressed in endocrine and neuronal cells. We investigated clinical and molecular features of PC1/3 deficiency. METHODS: We studied the clinical features of 13 children with PC1/3 deficiency and performed sequence analysis of PCSK1. We measured enzymatic activity of recombinant PC1/3 proteins. RESULTS: We identified a pattern of endocrinopathies that develop in an age-dependent manner. Eight of the mutations had severe biochemical consequences in vitro. Neonates had severe malabsorptive diarrhea and failure to thrive, required prolonged parenteral nutrition support, and had high mortality. Additional endocrine abnormalities developed as the disease progressed, including diabetes insipidus, growth hormone deficiency, primary hypogonadism, adrenal insufficiency, and hypothyroidism. We identified growth hormone deficiency, central diabetes insipidus, and male hypogonadism as new features of PCSK1 insufficiency. Interestingly, despite early growth abnormalities, moderate obesity, associated with severe polyphagia, generally appears. CONCLUSIONS: In a study of 13 children with PC1/3 deficiency caused by disruption of PCSK1, failure of enteroendocrine cells to produce functional hormones resulted in generalized malabsorption. These findings indicate that PC1/3 is involved in the processing of one or more enteric hormones that are required for nutrient absorption.


Subject(s)
Diarrhea/etiology , Endocrine System Diseases/etiology , Malabsorption Syndromes/etiology , Obesity/complications , Proprotein Convertase 1/deficiency , Adolescent , Adrenocorticotropic Hormone/blood , Child , Child, Preschool , Cohort Studies , Endocrine System Diseases/complications , Endocrine System Diseases/congenital , Female , Humans , Infant , Male , Mutation , Obesity/congenital , Proprotein Convertase 1/genetics
11.
Clin Exp Rheumatol ; 32(3): 424-31, 2014.
Article in English | MEDLINE | ID: mdl-24387974

ABSTRACT

OBJECTIVES: A significant proportion of patients with juvenile spondyloarthritis (JSpA) are refractory to treatment with established medications. The objective of this study was to assess long-term efficacy of treatment with anti-TNF agents in patients with JSpA. METHODS: An observational study of 16 patients with JSpA from 3 centres treated with infliximab (n=10) and etanercept (n=6) was performed, with a median follow-up period of 7.2 years. Prospective data was collected according to a standardized protocol. Outcomes examined were TEC, TAJC, markers of inflammation (ESR, CRP), functional assessments (C-HAQ, BASDAI, BASFI), and ongoing requirement for anti-TNF treatment. RESULTS: 13/16 patients (83%) had achieved clinical remission 6 months into the treatment. Improvement was sustained over time, with a median TAJC and TEC of 0 at any time point after 6 weeks. 6/16 patients (38%) showed a flare of arthritis after a median of 3.5 years. Two patients with hip disease prior to treatment required an arthroplasty 3 and 8 years post anti-TNF initiation. Patients showed progression of sacroiliitis with median modified New York score of 1 (range 0-3) at time of diagnosis and 3 (range 0-4) at last follow-up (p=0.002). Median BASDAI at last follow up was 1.6, median BASFI 3.1. Two patients developed transient reactions (one generalised, one local); no patient developed other adverse effects during the study. CONCLUSIONS: Anti-TNF treatment in JSpA refractory to standard treatment results in good long-term disease control except for pre-existing hip disease. However, radiographic evidence suggests inferior efficacy for control of sacroiliac joint disease.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antirheumatic Agents/therapeutic use , Immunoglobulin G/therapeutic use , Receptors, Tumor Necrosis Factor/therapeutic use , Spondylarthritis/drug therapy , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adolescent , Arthritis, Juvenile/drug therapy , Child , Etanercept , Female , Follow-Up Studies , Humans , Infliximab , Longitudinal Studies , Male , Sacroiliitis/drug therapy , Treatment Outcome
12.
Environ Technol ; 35(5-8): 727-34, 2014.
Article in English | MEDLINE | ID: mdl-24645453

ABSTRACT

Waste stabilization ponds (WSPs) are a cost-efficient method to treat municipal and non-toxic industrial effluents. Numerous studies have shown that WSPs are a source of greenhouse gas (GHG). However, most reports concerned anaerobic ponds (AP) and few have addressed GHG emissions from facultative (FP) and aerobic/maturation ponds (MPs). In this paper, GHG emissions from three WSP in series are presented. These WSPs were designed as anaerobic, facultative and aerobic/maturation and were treating agricultural wastewater. CH4 fluxes from 0.6 +/- 0.4 g CH4 m(-2) d(-1) in the MP, to 7.0 +/- 1.0 g CH4 m(-2) d(-1) in the (AP), were measured. A linear correlation was found between the loading rates of the ponds and CH4 emissions. Relatively low CO2 fluxes (0.2 +/- 0.1 to 1.0 +/- 0.8 g CO2 m(-2) d(-1)) were found, which suggest that carbonate/bicarbonate formation is caused by alkaline pH. A mass balance performed showed that 30% of the total chemical oxygen demand removed was converted to CH4. It has been concluded that the WSP system studied emits at least three times more GHG than aerobic activated sludge systems and that the surface loading rate is the most important design parameter for CH4 emissions.


Subject(s)
Gases , Greenhouse Effect , Refuse Disposal/methods , Waste Disposal, Fluid/methods , Water Purification/methods , Agriculture , Anaerobiosis , Biological Oxygen Demand Analysis , Carbon Dioxide/chemistry , Climate , Environmental Monitoring , Geography , Methane/chemistry , Mexico , Nitrogen/chemistry , Phosphorus/chemistry , Sewage , Sulfur/chemistry , Wastewater , Water Pollutants, Chemical
13.
Chemosphere ; 366: 143455, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39366489

ABSTRACT

This study presents the effect of natural zeolite (NZ) on a nitrifying sequencing batch reactor for removing ibuprofen (IBP) and diclofenac (DFC) in the long term, including kinetics and microbial community. The research was conducted in two 2 L liquid-volume bioreactors, one with 5 g/L of NZ. Nitrogen load rates ranging between 5.8 and 8.5 mg N/L h were studied. Bioreactors were operated for 217 days, with IBP and DFC concentrations ranging between 20 and 2000 µg/L. The results showed that using NZ in a nitrifying SBR only improves IBP removal at low concentrations (40 µg/L). IBP and DFC do not affect the nitrification efficiency or kinetic of ammonia removal. In the presence of IBP and DFC, NZ also favored a higher relative abundance in the genus Nitrosomonas and the Bradyrhizobiaceae family (responsible for nitrite-oxidizing activity), allowing higher IBP degradations at low IBP concentrations. Finally, IBP and DFC stimulated heterotrophic nitrification.

14.
Article in English | MEDLINE | ID: mdl-39044860

ABSTRACT

Introduction: Severe forms of short bowel syndrome (SBS) resulting in chronic intestinal failure (IF) have limited therapeutic options, all of which are associated with significant morbidities. Spring-mediated distraction enterogenesis (SMDE) uses an intraluminal self-expanding spring to generate mechanical force to induce intestinal stretching and sustained axial growth, providing a promising novel approach for patients with SBS. Previous studies have established this method to be safe and effective in small and large animal models. However, SMDE has previously not been implemented in a large, clinically relevant animal model. Methods: Juvenile mini-Yucatan pigs with 75% of their small intestine resected had intraluminal springs placed after an initial adaptive period. Morphological and histological assessments were performed on SMDE segments compared to the control region of the intestine undergoing normal adaptive responses to resection. Results: While the initial histologic adaptive response observed following resection was attenuated after a month, the SMDE segments instead augmented these adaptive changes. Specifically, intestinal length increased 2-fold in SMDE segments, and the widths of the epithelial, muscularis, and serosal layers were enhanced in SMDE compared with control segments of the same animal. This data suggests that morphologic intestinal adaptation may be enhanced with SMDE in the setting of SBS. Discussion: Here we demonstrate the successful and reproducible implementation of SMDE in a large animal model in the setting of prior intestinal resection, making SMDE a viable and novel approach for SBS to be explored further.

15.
Sci Total Environ ; 951: 175503, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39147045

ABSTRACT

Soil salinization is a gradual degradation process that begins as a minor problem and grows to become a significant economic loss if no control action is taken. It progressively alters the soil environment which eventually negatively affects plants and organism that were not originally adapted for saline conditions. Soil salinization arises from diverse sources such as side-effects of long-term use of agro-chemicals, saline parent rocks, periodic inundation of soil with saline water, etc. In Africa, soil salinization has not been adequately documented particularly in the croplands. The objective of this study was to identify trends of cropland salinization in Africa and how its relationship with long-term land use practices affected the soil environment. The study analysed soil salinization between 1965 and 2020 using measured electrical conductivity (EC), spatial modelling with environmental covariates, and national statistics on cropland expansion and application of mineral fertilizers, herbicides, and pesticides. The results showed increasing trends of EC in Africa due to climatic and land use drivers. Increasing trends of EC, which evidenced salinization, was found in 31 million hectares of topsoils and 18 million hectares of subsoils. About 2 million hectares of croplands were depicted with salinization and >25 million hectares at the risk of salinization in the arid and semi-arid areas. The study also found statistical relationships between semi-arid cropland salinization and trends of agro-chemical use and cropland sizes. There were significant (p < 0.001) positive correlations between semi-arid cropland salinization and trends of cropland expansion and applied nitrogenous fertilizers. It found that increasing trend of applied mineral nitrogenous fertilizers could double the odds of salinization in semi-arid croplands while cropland expansion could increase the odds of semi-arid cropland salinization by >10 %. These findings present ground-breaking baseline information for future works on sustainable land-use practices that can control cropland soil salinization in Africa.

16.
Mol Ecol ; 22(24): 6100-15, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24118534

ABSTRACT

Resolving phenotype variation within a population in response to environmental perturbation is central to understanding biological adaptation. Relating meaningful adaptive changes at the level of the transcriptome requires the identification of processes that have a functional significance for the individual. This remains a major objective towards understanding the complex interactions between environmental demand and an individual's capacity to respond to such demands. The interpretation of such interactions and the significance of biological variation between individuals from the same or different populations remain a difficult and under-addressed question. Here, we provide evidence that variation in gene expression between individuals in a zebrafish population can be partially resolved by a priori screening for animal personality and accounts for >9% of observed variation in the brain transcriptome. Proactive and reactive individuals within a wild-type population exhibit consistent behavioural responses over time and context that relates to underlying differences in regulated gene networks and predicted protein-protein interactions. These differences can be mapped to distinct regions of the brain and provide a foundation towards understanding the coordination of underpinning adaptive molecular events within populations.


Subject(s)
Behavior, Animal , Brain/physiology , Personality/genetics , Zebrafish/genetics , Analysis of Variance , Animals , Cluster Analysis , Female , Gene Expression , Gene Ontology , Male , Oligonucleotide Array Sequence Analysis , Principal Component Analysis , Protein Interaction Maps , Transcriptome , Zebrafish/physiology
17.
J Exp Biol ; 216(Pt 11): 2017-30, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23430990

ABSTRACT

An experimental investigation of near field aerodynamics of wind dispersed rotary seeds has been performed using stereoscopic digital particle image velocimetry (DPIV). The detailed three-dimensional flow structure of the leading-edge vortex (LEV) of autorotating mahogany seeds (Swietenia macrophylla) in a low-speed vertical wind tunnel is revealed for the first time. The results confirm that the presence of strong spanwise flow and strain produced by centrifugal forces through a spiral vortex are responsible for the attachment and stability of the LEV, with its core forming a cone pattern with a gradual increase in vortex size. The LEV appears at 25% of the wingspan, increases in size and strength outboard along the wing, and reaches its maximum stability and spanwise velocity at 75% of the wingspan. At a region between 90 and 100% of the wingspan, the strength and stability of the vortex core decreases and the LEV re-orientation/inflection with the tip vortex takes place. In this study, the instantaneous flow structure and the instantaneous velocity and vorticity fields measured in planes parallel to the free stream direction are presented as contour plots using an inertial and a non-inertial frame of reference. Results for the mean aerodynamic thrust coefficients as a function of the Reynolds number are presented to supplement the DPIV data.


Subject(s)
Meliaceae/anatomy & histology , Seeds/anatomy & histology , Biomechanical Phenomena , Models, Biological , Rheology , Wind
18.
Scand J Rheumatol ; 42(2): 102-7, 2013.
Article in English | MEDLINE | ID: mdl-23244209

ABSTRACT

BACKGROUND: Several studies have confirmed that galectin-1 (Gal-1) plays a role in controlling the immune response because of its pro-apoptotic effect. Although studies based on a rheumatoid arthritis (RA) mouse model have suggested a crucial role for Gal-1 in inflammation, clinical data are lacking. We have detected the presence of autoantibodies against galectins in blood, but their physiological meaning remains unknown. OBJECTIVES: To compare plasma and synovial levels of Gal-1 in RA patients and in healthy controls, and correlate them with clinical parameters. METHODS: Plasma and synovial (non-arthritic knee effusion) samples were collected from RA patients and healthy donors. All patients were receiving treatment with steroids and/or disease-modifying anti-rheumatic drugs (DMARDs). A blood sample was taken at a baseline visit to determine plasma anti-cyclic citrullinated peptide (anti-CCP) antibodies, tumour necrosis factor alpha (TNF-α), Gal-1, and anti-Gal-1 autoantibodies. RESULTS: Although plasma levels of Gal-1 were similar in patients and controls, the concentration of Gal-1 was significantly reduced in the synovial fluid of patients with RA. This reduction was not correlated with TNF-α or C-reactive protein (CRP) levels. However, the decrease in synovial Gal-1 correlated with a significant increase in anti-Gal-1 autoantibodies and anti-CCP antibody titres, suggesting a physiological effect of autoantibodies limiting the amount Gal-1 and potentially blocking its biological effect in RA patients. CONCLUSION: Gal-1 levels were significant reduced at the synovial level in RA patients, possibly as a consequence of the increase in anti-Gal-1 autoantibodies.


Subject(s)
Arthritis, Rheumatoid/blood , Autoantibodies/blood , Galectin 1/blood , Synovial Fluid/metabolism , Adult , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Peptides, Cyclic/immunology , Tumor Necrosis Factor-alpha/immunology , Young Adult
19.
J Biol Regul Homeost Agents ; 27(4): 989-99, 2013.
Article in English | MEDLINE | ID: mdl-24382180

ABSTRACT

AMP-activated protein kinase (AMPK) is a sensor of energy status supporting cellular energy homeostasis that may represent the metabolic basis for 3,3,,5-triiodo-L-thyronine (T3) liver preconditioning. Functionally transient hyperthyroid state induced by T3 (single dose of 0.1 mg/kg) in fed rats led to upregulation of mRNA expression (RT-PCR) and protein phosphorylation (Western blot) of hepatic AMPK at 8 to 36 h after treatment. AMPK Thr 172 phosphorylation induced by T3 is associated with enhanced mRNA expression of the upstream kinases Ca2+ -calmodulin-dependent protein kinase kinase-beta (CaMKKbeta) and transforming growth-factor-beta-activated kinase-1 (TAK1), with increased protein levels of CaMKKbeta and higher TAK1 phosphorylation, without changes in those of the liver kinase B1 (LKB1) signaling pathway. Liver contents of AMP and ADP were augmented by 291 percent and 44 percent by T3 compared to control values (p less than 0.05), respectively, whereas those of ATP decreased by 64% (p less than 0.05), with no significant changes in the total content of adenine nucleotides (AMP + ADP + ATP) at 24 h after T3 administration. Consequently, hepatic ATP/ADP content ratios exhibited 64 percent diminution (p less than 0.05) and those of AMP/ATP increased by 425 percent (p less than 0.05) in T3-treated rats over controls. It is concluded that in vivoT3 administration triggers liver AMPK upregulation in association with significant enhancements in AMPK mRNA expression, AMPK phosphorylation coupled to CaMKKbeta and TAK1 activation, and in AMP/ATP ratios, which may promote enhanced AMPK activity to support T3-induced energy consuming processes such as those of liver preconditioning.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Kinase/genetics , Liver/metabolism , MAP Kinase Kinase Kinases/genetics , Protein Serine-Threonine Kinases/genetics , Triiodothyronine/pharmacology , AMP-Activated Protein Kinase Kinases , Animals , Energy Metabolism , Male , Phosphorylation , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley
20.
J Pediatr Gastroenterol Nutr ; 57(6): 759-67, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24280991

ABSTRACT

OBJECTIVES: Congenital diarrhea disorders are a group of genetically diverse and typically autosomal recessive disorders that have yet to be well characterized phenotypically or molecularly. Diagnostic assessments are generally limited to nutritional challenges and histologic evaluation, and many subjects eventually require a prolonged course of intravenous nutrition. Here we describe next-generation sequencing techniques to investigate a child with perplexing congenital malabsorptive diarrhea and other presumably unrelated clinical problems; this method provides an alternative approach to molecular diagnosis. METHODS: We screened the diploid genome of an affected individual, using exome sequencing, for uncommon variants that have observed protein-coding consequences. We assessed the functional activity of the mutant protein, as well as its lack of expression using immunohistochemistry. RESULTS: Among several rare variants detected was a homozygous nonsense mutation in the catalytic domain of the proprotein convertase subtilisin/kexin type 1 gene. The mutation abolishes prohormone convertase 1/3 endoprotease activity as well as expression in the intestine. These primary genetic findings prompted a careful endocrine reevaluation of the child at 4.5 years of age, and multiple significant problems were subsequently identified consistent with the known phenotypic consequences of proprotein convertase subtilisin/kexin type 1 (PCSK1) gene mutations. Based on the molecular diagnosis, alternate medical and dietary management was implemented for diabetes insipidus, polyphagia, and micropenis. CONCLUSIONS: Whole-exome sequencing provides a powerful diagnostic tool to clinicians managing rare genetic disorders with multiple perplexing clinical manifestations.


Subject(s)
Codon, Nonsense , Diabetes Insipidus/complications , Diarrhea/genetics , Exome , Malabsorption Syndromes/genetics , Proprotein Convertase 1/genetics , Diarrhea/congenital , Diarrhea/diagnosis , Homozygote , Humans , Infant, Newborn , Malabsorption Syndromes/congenital , Malabsorption Syndromes/diagnosis , Male , Proprotein Convertase 1/metabolism , Sequence Analysis, DNA
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