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2.
Proc Natl Acad Sci U S A ; 117(13): 7263-7270, 2020 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-32165545

RESUMEN

Spatial heterogeneity in composition and function enables ecosystems to supply diverse services. For soil microbes and the ecosystem functions they catalyze, whether such heterogeneity can be maintained in the face of altered resource inputs is uncertain. In a 50-ha northern California grassland with a mosaic of plant communities generated by different soil types, we tested how spatial variability in microbial composition and function changed in response to nutrient and water addition. Fungal composition lost some of its spatial variability in response to nutrient addition, driven by decreases in mutualistic fungi and increases in antagonistic fungi that were strongest on the least fertile soils, where mutualists were initially most frequent and antagonists initially least frequent. Bacterial and archaeal community composition showed little change in their spatial variability with resource addition. Microbial functions related to nitrogen cycling showed increased spatial variability under nutrient, and sometimes water, additions, driven in part by accelerated nitrification on the initially more-fertile soils. Under anthropogenic changes such as eutrophication and altered rainfall, these findings illustrate the potential for significant changes in ecosystem-level spatial heterogeneity of microbial functions and communities.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Microbiota/fisiología , Microbiología del Suelo , Archaea/fisiología , Bacterias , Demografía/métodos , Ecosistema , Hongos/fisiología , Nitrificación , Nitrógeno/análisis , Lluvia , Suelo , Simbiosis , Agua
3.
Biochem Genet ; 61(4): 1401-1417, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36624353

RESUMEN

Philippine native pigs (PhNP) are small black pigs domesticated in rural communities in the Philippines. They are valued locally for their various sociocultural roles. Recently, considerable literature has accumulated in the field of native pig production and marketing. However, there is limited research on the genetic diversity of PhNP. No previous study has investigated the evolutionary relatedness among native pigs from various islands and provinces in Luzon and the Visayas, Philippines. In addition, a much debated question is whether the PhNP were interbreeding with or even domesticated from endemic wild pigs. This study aims to clarify some of the uncertainties surrounding the identity and classification of PhNP based on mitochondrial DNA (mtDNA) signatures. Native pig samples (n = 157) were collected from 10 provinces in Luzon and the Visayas. Approximately 650 base pairs of the mtDNA D-loop region were sequenced and analyzed together with publicly available sequences. Pairwise-distance analysis showed genetic separation of North and South Luzon (SL) and the clustering of SL with Visayan pigs. Phylogenetic analysis showed that the PhNP clustered within 3 recognized Asian pig domestication centers: D2 (East Asia), D7 (Southeast Asia) and the Cordillera clade (sister to the Lanyu). We identified 19 haplotypes (1-38 samples each), forming 4 haplogroups, i.e., North Luzon, South Luzon and Visayas, Asian mix and the Cordillera cluster. No endemic wild pig mtDNA was detected in the native pig population, but evidence of interspecific hybridization was observed. This study showed that the Philippine native pigs have originated from at least 3 Sus scrofa lineage and that they were not domesticated from the endemic wild pigs of the Philippines.


Asunto(s)
ADN Mitocondrial , Variación Genética , Animales , Porcinos/genética , ADN Mitocondrial/genética , Filogenia , Filipinas , Haplotipos , Sus scrofa/genética
4.
Appl Nurs Res ; 74: 151732, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38007244

RESUMEN

BACKGROUND: Early breastfeeding initiation (EBI) within the first hour after birth has the potential to reduce neonatal mortality. However, the prevalence of EBI still falls short of the 70 % target set by the WHO for 2030. Limited research has been conducted on this issue. Therefore, the study aimed to assess the prevalence and factors of EBI in the Philippines. METHODS: This study is a secondary analysis of the data from the Philippine National Demographic and Health Survey (PNDHS) in 2017. Women survey participants aged 15 to 49 (n = 3750) who had given birth within the two years prior to the survey were included in this study. A p-value < 0.05 was used to define statistical significance when identifying the factors associated with EBI using hierarchical logistic regression analysis. RESULTS: Women who were more likely to practice EBI were those from the Cordillera Administrative Region, who read newspaper/magazines, and delivered infants at 2 or later birth order. On the contrary, women from Central Luzon, CALABARZON (Cavite, Laguna, Batangas, Rizal, and Quezon provinces), Central Visayas, Eastern Visayas, and the Autonomous Region of Muslim Mindanao; who listen to the radio at least once a week; and give birth through cesarean section were less likely to practice EBI. CONCLUSION: Channeling breastfeeding messages through printed mass media and provision of specialized breastfeeding support to mothers with cesarean section delivery may help in reducing the barriers to early breastfeeding initiation. Targeted interventions and strategies that promote breastfeeding practices, particularly among primigravida women and in regions with lower rates of EBI contribute to increased rate of optimal breastfeeding.


Asunto(s)
Lactancia Materna , Cesárea , Lactante , Recién Nacido , Femenino , Embarazo , Humanos , Estudios Transversales , Filipinas , Madres
6.
J Virol ; 94(22)2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-32878889

RESUMEN

Oryctes rhinoceros nudivirus (OrNV) is a double-stranded DNA (dsDNA) virus which has been used as a biocontrol agent to suppress the coconut rhinoceros beetle (Oryctes rhinoceros) in Southeast Asia and the Pacific Islands. A new wave of O. rhinoceros incursions in Oceania is thought to be related to the presence of low-virulence isolates of OrNV or virus-tolerant haplotypes of beetles. In this study, chronically infected beetles were collected from Philippines, Fiji, Papua New Guinea (PNG), and the Solomon Islands (SI). RNA sequencing (RNA-seq) was performed to investigate the global viral gene expression profiles and for comparative genomic analysis of structural variations. Maximum likelihood phylogenic analysis indicated that OrNV strains from the SI and Philippines are closely related, while OrNV strains from PNG and Fiji formed a distinct adjacent clade. We detected several polymorphic sites with a frequency higher than 35% in 892 positions of the viral genome. Nonsynonymous mutations were detected in several hypothetical proteins and 15 nudivirus core genes, such as gp034, lef-8, lef-4, and vp91 We found limited evidence of variation in viral gene expression among geographic populations. Only a few genes, such as gp01, gp022, and gp107, were differentially expressed among different strains. Additionally, small RNA sequencing from the SI population suggested that OrNV is targeted by the host RNA interference (RNAi) response with abundant 21-nucleotide small RNAs. Some of these genomic changes are specific to the geographic population and could be related to particular phenotypic characteristics of the strain, such as viral pathogenicity or transmissibility, and this requires further investigation.IMPORTANCE Oryctes rhinoceros nudivirus has been an effective biocontrol agent against the coconut rhinoceros beetle in Southeast Asia and the Pacific Islands for decades. The recent outbreak of these beetles in many South Pacific islands has had a significant impact on livelihoods in the region. It has been suggested that the resurgence and spread of the pest are related to the presence of low-virulence isolates of OrNV or virus-tolerant haplotypes of beetles. We examined viral genomic and transcriptional variations in chronically infected beetles from different geographical populations. A high number of polymorphic sites among several geographical strains of OrNV were identified, but potentially only a few of these variations in the genome are involved in functional changes and can potentially alter the typical function. These findings provide valuable resources for future studies to improve our understanding of the OrNV genetic variations in different geographic regions and their potential link to virus pathogenicity.


Asunto(s)
Escarabajos/virología , Genoma Viral , Genómica , Nudiviridae/genética , Animales , Cocos , ADN , Virus ADN/genética , Femenino , Regulación Viral de la Expresión Génica , Genes Virales/genética , Haplotipos , MicroARNs , Oceanía , Perisodáctilos , Filogenia , Interferencia de ARN , Análisis de Secuencia de ARN
7.
Fish Shellfish Immunol ; 117: 291-298, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34419600

RESUMEN

This study investigated the immunomodulatory effects of Sargassum polycystum extract administration in rainbow trout (Oncorhynchus mykiss). S. polycystum methanolic extract was administered orally using feeding needles to individual rainbow trout at the dose of 0 (control), 1 (S1), 3 (S3) and 5 (S5) mg/100 µl/per fish twice a day for 7 days. On 1st, 5th, 3rd and 7th day, blood and tissues were collected from the fish and changes in humoral immune responses and immune-related gene expressions were determined. The result of oxidative radical production showed no difference during early stage of the experiment and was lately decreased (P < 0.05). Lysozyme activity increased on 3rd and 7th day of the study in S5 fish group and on 5th day in S3 group compared to control (P < 0.05). Myeloperoxidase activity had an increased level on the 1st and 3rd day in S1, S5 and S5 fish groups, respectively. IL-1ß gene was significantly up-regulated in kidney and intestine in all experimental groups (except on the 1st day, in the intestine of S5 fish group) compared to control (P < 0.05). IL-8 gene expression was elevated on 1st and 3rd day in kidney of all experimental fish groups. IL-6 transcript enhanced in a dose-dependent manner on 3rd and 7th day. IL-10 and IL-12 genes were also up-regulated. Survival in all treated fish groups challenged with Aeromonas hydrophila was significantly increased compared to that of control. The highest survival rate was recorded in S5 fish group (83.65%) followed by S3 fish group (82.62%). Our results suggest that S. polycystum aqueous methanolic extract is an effective immunostimulant and provide protection against A. hydrophila infection in rainbow trout at a dose of 3-10 mg/20 g body weight/day.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Aeromonas hydrophila , Mezclas Complejas/farmacología , Enfermedades de los Peces/inmunología , Infecciones por Bacterias Gramnegativas/inmunología , Oncorhynchus mykiss/inmunología , Sargassum , Administración Oral , Animales , Citocinas/genética , Citocinas/inmunología , Enfermedades de los Peces/mortalidad , Infecciones por Bacterias Gramnegativas/mortalidad , Infecciones por Bacterias Gramnegativas/veterinaria , Muramidasa/inmunología , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/microbiología , Peroxidasa/inmunología
8.
J Environ Manage ; 231: 1270-1276, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30602252

RESUMEN

The Storm Water Management Model (SWMM), with its recently released low impact development (LID) module, is among several models used for the performance evaluation of LID facilities in reducing runoff and pollutants. Modeling is often difficult because of the variety of factors affecting the LID system. Among these factors, the effect of groundwater can be important in the LID modeling results due to the possibility of its interaction with LID. In this study, the performance of the SWMM-LID controls in predicting runoff from bioretention cells was evaluated for a site under groundwater influence. In addition, for considering the groundwater effect in the model, this study explores the utility of the SWMM groundwater model in predicting runoff under groundwater influence. Runoff from the considered watershed draining into the bioretention cells was well-simulated with very favorable performance statistic values (r2 = 0.96, NSE = 0.94, % difference = 2.76). However, comparison of simulated with observed runoff from bioretention cells produced weaker statistical values (r2 = 0.69, NSE = 0.65, % difference = 18.22), which is thought to be due to the presence of events affected by groundwater interference. Removal of these events and recalibration were able to improve the overall results, suggesting that the influence of groundwater should be taken into account for better LID modeling of the study site. In order to consider the groundwater influence, the SWMM groundwater model was used in tandem with LID controls to provide an additional influent source to bioretention cells. This resulted in a good fit for two events which were thought to be impacted by groundwater (events in which outflow exceeded inflow) and overall better performance (r2 = 0.95, NSE = 0.95, % difference = 3.49) compared to the results obtained by using only LID controls. In conclusion, the SWMM groundwater model can help deal with groundwater-impacted events. However, for better representation of the phenomenon, the LID module itself needs to be improved to account for direct interaction with groundwater.


Asunto(s)
Agua Subterránea , Movimientos del Agua , Lluvia , Agua
9.
Am Nat ; 192(5): 618-629, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30332582

RESUMEN

Symbiotic nitrogen fixation (SNF) makes atmospheric nitrogen biologically available and regulates carbon storage in many terrestrial ecosystems. Despite its global importance, estimates of SNF rates are highly uncertain, particularly in tropical forests where rates are assumed to be high. Here we provide a framework for evaluating the uncertainty of sample-based SNF estimates and discuss its implications for quantifying SNF and thus understanding of forest function. We apply this framework to field data sets from six lowland tropical rainforests (mature and secondary) in Brazil and Costa Rica. We use this data set to estimate parameters influencing SNF estimation error, notably the root nodule abundance and variation in SNF rates among soil cores containing root nodules. We then use simulations to gauge the relationship between sampling effort and SNF estimation accuracy for a combination of parameters. Field data illuminate a highly right-skewed lognormal distribution of SNF rates among soil cores containing root nodules that were rare and spanned five orders of magnitude. Consequently, simulations demonstrated that sample sizes of hundreds to even thousands of soil cores are needed to obtain estimates of SNF that are within, for example, a factor of 2 of the actual rate with 75% probability. This represents sample sizes that are larger than most studies to date. As a result of this previously undescribed uncertainty, we suggest that current estimates of SNF in tropical forests are not sufficiently constrained to elucidate forest stand-level controls of SNF, which hinders our understanding of the impact of SNF on tropical forest ecosystem processes.


Asunto(s)
Fijación del Nitrógeno , Bosque Lluvioso , Nódulos de las Raíces de las Plantas/metabolismo , Bacterias , Brasil , Simulación por Computador , Costa Rica , Suelo/química , Simbiosis/fisiología , Clima Tropical
10.
Ecology ; 99(11): 2496-2505, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30076606

RESUMEN

Free-living heterotrophic nitrogen fixation (FNF) is a widespread nitrogen input pathway in terrestrial ecosystems. However, questions remain over the relative influence of co-occurring controls on patterns of heterotrophic FNF activity, especially across generalized stages of primary succession, from biomass accumulation to retrogressive phases. Here, we experimentally test two alternative hypotheses regarding FNF rates during ecosystem development: (H1) site (i.e., changes in soil fertility during succession) is the primary driver of leaf-litter FNF rates, vs. (H2) leaf-litter chemistry is the primary determinant of FNF activity across a broad range of ecosystem conditions. We evaluated these hypotheses across a well-studied soil chronosequence in California (i.e., the Ecological Staircase), which spans ~1 million years of ecosystem development and displays extreme ranges in plant-soil nutrient conditions, culminating in the nutrient depleted and stunted Pygmy forest. Across this successional gradient, we implemented a reciprocal leaf-litter transplant and a common garden litter bag decomposition experiment with senesced needles of Pinus muricata. Our results support H1: rates of FNF were similar for all leaf-litter types decomposed at the same site regardless of initial leaf-litter C and nutrient contents. FNF rates sharply declined from the maximal to retrogressive stage of succession. Trends in P dynamics during decomposition suggest an important role of P in regulating FNF. For example, P. muricata litter collected from the infertile Pygmy site displayed substantially higher FNF rates when decomposed at the fertile site, in part by immobilizing significant quantities of P from the soil at the fertile site. Conversely, P. muricata litter collected from the fertile site decomposed more slowly at the Pygmy site, with concomitant declines in FNF rates that matched those of Pygmy site litter decomposed in situ. These results are consistent with the idea that, over millennia, long-term declines in P availability feedback to constrain FNF rates, in part explaining the emergence of extremely nutrient-poor and retrograded ecosystems.


Asunto(s)
Fijación del Nitrógeno , Suelo/química , California , Ecosistema , Nitrógeno , Hojas de la Planta/química
12.
Proc Natl Acad Sci U S A ; 112(52): E7249-56, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26668372

RESUMEN

Whereas several mammalian proteins can restrict the replication of HIV-1 and other viruses, these are often not expressed in relevant target cells. A potential method to inhibit viral replication might therefore be to use synthetic transcription factors to induce restriction factor expression. In particular, mutants of the RNA-guided DNA binding protein Cas9 that have lost their DNA cleavage activity could be used to recruit transcription activation domains to specific promoters. However, initial experiments revealed only weak activation unless multiple promoter-specific single guide RNAs (sgRNAs) were used. Recently, the recruitment of multiple transcription activation domains by a single sgRNA, modified to contain MS2-derived stem loops that recruit fusion proteins consisting of the MS2 coat protein linked to transcription activation domains, was reported to induce otherwise silent cellular genes. Here, we demonstrate that such "synergistic activation mediators" can induce the expression of two restriction factors, APOBEC3G (A3G) and APOBEC3B (A3B), in human cells that normally lack these proteins. We observed modest activation of endogenous A3G or A3B expression using single sgRNAs but high expression when two sgRNAs were used. Whereas the induced A3G and A3B proteins both blocked infection by an HIV-1 variant lacking a functional vif gene by inducing extensive dC-to-dU editing, only the induced A3B protein inhibited wild-type HIV-1. These data demonstrate that Cas9-derived transcriptional activators have the potential to be used for screens for endogenous genes that affect virus replication and raise the possibility that synthetic transcription factors might prove clinically useful if efficient delivery mechanisms could be developed.


Asunto(s)
Sistemas CRISPR-Cas/genética , Citidina Desaminasa/genética , Activación Transcripcional , Desaminasa APOBEC-3G , Secuencia de Bases , Western Blotting , Línea Celular , Citidina Desaminasa/metabolismo , Expresión Génica , Células HEK293 , Células HeLa , Humanos , Antígenos de Histocompatibilidad Menor , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Productos del Gen vif del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen vif del Virus de la Inmunodeficiencia Humana/metabolismo
13.
Proc Natl Acad Sci U S A ; 112(50): E6945-54, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26621737

RESUMEN

Although RNA interference (RNAi) functions as a potent antiviral innate-immune response in plants and invertebrates, mammalian somatic cells appear incapable of mounting an RNAi response and few, if any, small interfering RNAs (siRNAs) can be detected. To examine why siRNA production is inefficient, we have generated double-knockout human cells lacking both Dicer and protein kinase RNA-activated. Using these cells, which tolerate double-stranded RNA expression, we show that a mutant form of human Dicer lacking the amino-terminal helicase domain can process double-stranded RNAs to produce high levels of siRNAs that are readily detectable by Northern blot, are loaded into RNA-induced silencing complexes, and can effectively and specifically inhibit the expression of cognate mRNAs. Remarkably, overexpression of this mutant Dicer, but not wild-type Dicer, also resulted in a partial inhibition of Influenza A virus-but not poliovirus-replication in human cells.


Asunto(s)
ARN Interferente Pequeño/fisiología , Ribonucleasa III/genética , Eliminación de Secuencia , Células HEK293 , Humanos , ARN Viral/genética , Ribonucleasa III/química
14.
Ecology ; 98(3): 773-781, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27987310

RESUMEN

Limestone tropical forests represent a meaningful fraction of the land area in Central America (25%) and Southeast Asia (40%). These ecosystems are marked by high biological diversity, CO2 uptake capacity, and high pH soils, the latter making them fundamentally different from the majority of lowland tropical forest areas in the Amazon and Congo basins. Here, we examine the role of bedrock geology in determining biological nitrogen fixation (BNF) rates in volcanic (low pH) vs. limestone (high pH) tropical forests located in the Maya Mountains of Belize. We experimentally test how BNF in the leaf-litter responds to nitrogen, phosphorus, molybdenum, and iron additions across different parent materials. We find evidence for iron limitation of BNF rates in limestone forests during the wet but not dry season (response ratio 3.2 ± 0.2; P = 0.03). In contrast, BNF in low pH volcanic forest soil was stimulated by the trace-metal molybdenum during the dry season. The parent-material induced patterns of limitation track changes in siderophore activity and iron bioavailability among parent materials. These findings point to a new role for iron in regulating BNF in karst tropical soils, consistent with observations for other high pH systems such as the open ocean and calcareous agricultural ecosystems.


Asunto(s)
Bosques , Hierro/metabolismo , Fijación del Nitrógeno/fisiología , Clima Tropical , Belice , América Central , Ecosistema , Nitrógeno , Suelo , Árboles
15.
Ann Allergy Asthma Immunol ; 117(1): 38-42, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27221063

RESUMEN

BACKGROUND: Increased body mass index (BMI) may be a risk factor for the development and severity of asthma. However, the effect of obesity on asthma exacerbations is unclear. OBJECTIVE: To examine the association of obesity and the severity of acute asthma exacerbations. METHODS: A retrospective cohort of children aged 5 to 18 years who were seen in the emergency department and admitted for acute asthma exacerbation from 2009 to 2011 was reviewed. Weight and height data to compute the BMI were taken from the medical record review. The Centers for Disease Control and Prevention BMI-for-age growth charts for boys and girls aged 2 to 20 years were used to classify underweight, normal, overweight, and obese. Severity of asthma exacerbations into mild, moderate, or severe was determined using criteria by the Global Initiative for Asthma 2010. The χ(2) test of association or the Fisher exact probability test for small samples was used to determine the association between nutritional status and severity of asthma exacerbations. RESULTS: Of the 303 cases reviewed, most were boys with a mean (SD) age of 10 (3.8) years. The prevalence of overweight and obese children admitted for acute asthma exacerbation was 21% and 28%, respectively. No significant difference was found in the severity of asthma exacerbations, with 82.9% of the nonobese group and 86.8% of the overweight-obese group having moderate-to-severe exacerbation (likelihood ratio, 0.879; 95% CI, 0.42-0.41; P = .88). CONCLUSION: Our findings suggest that the severity of acute asthma exacerbations was not affected by increased BMI.


Asunto(s)
Asma/complicaciones , Asma/diagnóstico , Obesidad/complicaciones , Adolescente , Asma/epidemiología , Índice de Masa Corporal , Canadá , Niño , Preescolar , Comorbilidad , Progresión de la Enfermedad , Servicio de Urgencia en Hospital , Femenino , Humanos , Masculino , Estado Nutricional , Obesidad/epidemiología , Fenotipo , Filipinas/epidemiología , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Estados Unidos
16.
Methods ; 91: 82-86, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26291065

RESUMEN

RNA-guided endonucleases or CRISPR/Cas systems have been widely employed for gene engineering/DNA editing applications, and have recently been used against a variety of dsDNA viruses as a potential therapeutic. However, in vivo delivery to specific tissue reservoirs using adeno-associated virus (AAV) vectors is problematic due to the large coding requirement for the principal effector commonly used in these applications, Streptococcus pyogenes (Spy) Cas9. Here we describe design of a minimal CRISPR/Cas system that is capable of multiplexing and can be packaged into a single AAV vector. This system consists of the small Type II Cas9 protein from Staphylococcus aureus (Sau) driven by a truncated CMV promoter/enhancer, and flanked 3' by a poly(A) addition signal, as well as two sgRNA expression cassettes driven by either U6 or ∼70-bp tRNA-derived Pol III promoters. Specific protocols for construction of these AAV vector scaffolds, shuttle cloning of their contents into AAV and lentiviral backbones, and a quantitative luciferase assay capable of screening for optimal sgRNAs, are detailed. These protocols can facilitate construction of AAV vectors that have optimal multiplexed sgRNA expression and function. These will have potential utility in multiplex applications, including in antiviral therapy in tissues chronically infected with a pathogenic DNA virus.


Asunto(s)
Antivirales/uso terapéutico , Sistemas CRISPR-Cas , Terapia Genética/métodos , Vectores Genéticos , Virosis/terapia , Animales , Dependovirus/genética , Humanos , Regiones Promotoras Genéticas , Staphylococcus aureus/genética , Virosis/genética
17.
Water Sci Technol ; 73(7): 1583-90, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27054729

RESUMEN

Construction of hydraulic structures often leads to alteration of river dynamics and water quality. Suspended solids entering the upstream of the weir cause adverse effects to the hydroecological system and, therefore, it is necessary to build a modelling system to predict the changes in the river characteristics for proper water quality management. In this study, the discharges and total suspended solids upstream and downstream of the Baekje Weir installed in Geum River, Korea, was modelled using the environmental fluid dynamics code (EFDC) model. The resulting trend of four rainfall events shows that as rainfall increases, the total suspended solids (TSS) concentration increases as well. For the two larger events, at the upstream of the weir, TSS was observed to decrease or remain constant after the rainfall event depending on the lowering of the open gate. At the downstream, TSS supply was controlled by the weir during and after the rainfall event resulting in decline in the TSS concentration. The modelling produced good results for discharge based on %Diff. (4.37-6.35), Nash-Sutcliffe efficiency (NSE) (0.94-0.99) and correlation coefficient (r) (0.97-0.99) values as well as for TSS with acceptable values for %Diff. (12.08-14.11), NSE (0.75-0.81) and r (0.88-0.91), suggesting good applicability of the model for the weir reach of the river in the study site.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Ríos/química , Calidad del Agua , Hidrodinámica , Modelos Químicos , República de Corea , Factores de Tiempo , Movimientos del Agua
18.
Can J Diabetes ; 48(4): 233-243.e10, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38295879

RESUMEN

OBJECTIVES: Current medications for diabetic neuropathy (DN) recommended by the American Diabetes Association and American Academy of Neurology do not address the pathologic process of denervation among patients with DN, because ancillary treatments, such as reactive oxygen scavengers, may be needed. The purpose of this work was to summarize the available evidence about the efficacy and safety of alpha lipoic acid (ALA) and gamma linolenic acid (GLA) in the management of DN. METHODS: Using the search terms [(alpha lipoic acid or ALA or thioctic acid or thioctacid) or (gamma linolenic acid or GLA)] AND [(diabetes or diabetes mellitus) AND (polyneuropathy or neuropathy or sensorimotor polyneuropathy or radiculopathy)], 11 studies were included in this review and combined meta-analysis. RESULTS: Eight of the 11 articles (73%) reported significant benefit of ALA vs placebo. In the meta-analysis, the Total Symptom Score (TSS) for ALA 600 mg/day (ALA600) was 1.05 points lower (standard mean difference [SMD] -1.05, 95% confidence interval [CI] -2.07 to -0.04, p=0.04, I2=98.18%) compared with control at the end of the study. In the network meta-analysis, ALA600 (SMD -1.68, 95% CI -2.8 to -0.6) and GLA (SMD -2.39, 95% CI -4.3 to -0.5) had significantly lower TSSs compared with placebo. Moreover, GLA had the highest probability of being the best (52.7%) for improving DN symptoms. In all studies, most adverse events include gastrointestinal disturbances. In terms of tolerability, no differences were detected between ALA and control groups. CONCLUSION: ALA and GLA appear to be safe and efficacious biofactors for improvement of DN symptoms.


Asunto(s)
Neuropatías Diabéticas , Ácido Tióctico , Ácido gammalinolénico , Humanos , Ácido Tióctico/uso terapéutico , Neuropatías Diabéticas/tratamiento farmacológico , Ácido gammalinolénico/uso terapéutico , Ácido gammalinolénico/administración & dosificación , Metaanálisis en Red , Adulto , Resultado del Tratamiento , Antioxidantes/uso terapéutico , Antioxidantes/administración & dosificación
19.
Acta Neurol Belg ; 124(4): 1237-1250, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38553651

RESUMEN

INTRODUCTION: Small cross-sectional studies and case reports observed improvement after administration of second IVIG dose (SID) amongst Guillain-Barré Syndrome (GBS) patients not responsive to initial IVIG cycle. Nevertheless, recent clinical trial and larger observational studies did not find any positive effects of SID. Instead, an increased risk of thromboembolism and mortality was noted. The conclusions of these studies however were not robust as confounding and selection bias were present. METHODOLOGY: Two neurologists conducted the search process (KBA and MBP) using the following terms in Medline: [(" Guillain-Barré Syndrome"[MeSH Terms] or GBS or Acute Motor Axonal Neuropathy or Acute Motor Axonal Neuropathy or Acute Inflammatory Demyelinating Polyneuropathy) AND (Poorly Responsive or Poor Prognosis or Progressive)] AND [("Intravenous Immunoglobulin"[MeSH Terms] or IVIG or IGIV) AND (second dose or retreatment or SID)]. RESULTS: Only 7 articles were included in this review. In terms of primary outcomes, although the cross-sectional study found improvement in GBS DS score at 4 weeks (Median GBS DS: 3 vs 5, p = 0.033) and the 2 case series observed improvement after SID, no significant differences between the control and intervention groups were found in the cohort [Early SIV OR: 0.7 (95% CI 0.16-3.04), Late SIV OR: 0.66 (CI: 0.18-2.5)] and clinical trial studies (Adjusted OR: 1.4 (95% CI:0.6-3.3, p = 0.45). Moreover, 4 patients who died in the clinical trial were from the intervention group. CONCLUSION: Based on studies with research designs of higher quality, SID is not effective in the management of GBS patients who poorly responded to initial IVIG. Nevertheless, an adequately powered, randomized, double-blinded, placebo-controlled clinical trial, using GBS-DS of 3 and above after first IVIG dose should be done to effectively establish the efficacy and safety of SID as intervention for this cohort of patients.


Asunto(s)
Síndrome de Guillain-Barré , Inmunoglobulinas Intravenosas , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunoglobulinas Intravenosas/administración & dosificación , Síndrome de Guillain-Barré/tratamiento farmacológico , Factores Inmunológicos/uso terapéutico , Factores Inmunológicos/administración & dosificación , Retratamiento , Resultado del Tratamiento
20.
Toxicol Res (Camb) ; 13(3): tfae088, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38863797

RESUMEN

Introduction: There is a significant shortage of observational studies on neurotoxic snakebite envenomation in the Philippines. This lack of data, especially concerning treatment using Purified Cobra Antivenom (PCAV), has prompted the initiation of this foundational study. Methods: The target population included snakebite patients admitted to the Eastern Visayas Medical Center and treated with PCAV between 2016 and 2020. A retrospective chart review was conducted for data collection. The investigation analyzed the hospital stay and patient features of individuals who were administered either lower or higher doses of PCAV. Results: Eighty-two patients were identified during the study. Of these, 27 (33%) were under 20 years of age and 50 (61%) were male. Most patients, totalling 75 (92%) were hailed from rural areas. Of the 82 patients, 59 (72%) received one or two ampoules of PCAV during the course. However, patients who received more than two ampoules had a longer median hospital stay than those who received less than three ampoules [96 h (interquartile range, IQR 66-122) vs. 125 h (IQR 96-218), P = 0.038]. The study reported five in-hospital mortalities (6.1%). Conclusions: The individuals who needed a high dosage of PCAV tended to have more extended hospital stays, yet over 70% of the patient population required a lower dosage. To gain a clearer understanding of the burden of neurotoxic snakebites and determine the optimal PCAV dosage based on disease severity in the area, a more comprehensive, prospective study is recommended.

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