Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Mymensingh Med J ; 33(2): 516-525, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38557535

RESUMEN

Coronary artery bypass graft surgery (CABG) is a proven treatment for coronary artery disease. History of a ST-elevation myocardial infarction (STEMI) is considered an independent risk factor for CABG irrespective of timing for an emergency or elective surgery. Patients with STEMI are candidates for both On-pump and Off-pump CABG procedures. This paper discusses the possible best option for elective surgical revascularization in patients with prior STEMI. This prospective clinical trial of 60 eligible patients with prior STEMI was conducted in a Tertiary Care Hospital from April 2018 to March 2019. Among them, 30 patients underwent off-pump (Group A) and 30 patients underwent on-pump (Group B) CABG procedures. Outcomes between both groups were observed from surgery to 1 month postoperatively. Data was analysed by the software statistical program for social science (SPSS 25.0 Inc). The surgery was successful in both groups of patients. Differences were observed by mean number of grafts per patient (2.77±0.43 vs. 3.10±0.71) and duration of operation (4.41±0.35 hours vs. 5.71±0.48 hours). An improvement in Left Ventricular Ejection Fraction (LVEF %) was observed in both groups postoperatively (17.98% vs. 10.98%) and the postoperative LVEF% at different time points were found statistically significant (p<0.05) over preoperative LVEF%. Multivariable stepwise logistic regression analysis correlated on-pump CABG with prolonged need for ionotropic support, need for blood transfusion, longer hospital stay and less improvement in LVEF%. The study supports the Off-pump CABG as a better surgical option over on-pump CABG in patients with prior STEMI.


Asunto(s)
Enfermedad de la Arteria Coronaria , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/cirugía , Volumen Sistólico , Función Ventricular Izquierda , Puente de Arteria Coronaria/métodos , Enfermedad de la Arteria Coronaria/cirugía , Resultado del Tratamiento
3.
Mar Pollut Bull ; 201: 116185, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38412798

RESUMEN

Microplastics (MPs) were analyzed in seven shrimp species Tiger shrimp (Penaeus monodon), Red tiger shrimp (Caridina cantonensis), Indian shrimp (Penaeus indicus), Red shrimp (Metapenaeus dobsoni), White shrimp (Penaeus merguiensis), Brown shrimp (Metapenaeus monoceros), and Roshna shrimp (Palaemon styliferus) collected from the Bay of Bengal. The abundance and characteristics of MPs were assessed in the gastrointestinal tract (GIT), which certainly translocated to the muscle of shrimp species. The highest MP abundance was found in C. cantonensis with 7.2 items/individual (25.3 items/g in the GIT and 6.3 items/g in muscle). The prominent types of MPs in shrimp samples were fibers (30 %) and fragments (29 %). The ingestion rate of MPs of black and transparent color was comparatively higher, with 64 % of the ingested MPs were < 100 µm. The primary polymer types detected based on Fourier Transform Infrared (FTIR) analysis were Low-Density Polyethylene (LDPE), High-Density Polyethylene (HDPE), Polymethyl Methacrylate (PMMA), Polyvinyl Chloride (PVC), Polypropylene (PP), and Ethylene Vinyl Acetate (EVA). Results from Scanning Electron Microscopy (SEM) showed rough surface textures and adhered particles on the MPs isolated from shrimps. The margin of exposure for females was 71.42, and for males, it was 80.64, indicating that women in Bangladesh are more likely to be exposed to MPs and face a higher risk than men. Sensitivity analysis revealed that MPs particle size was the most sensitive parameter. These findings provide a comprehensive understanding of MP ingestion, human exposure, and contamination in shrimps of Bangladesh, which can help future monitoring efforts.


Asunto(s)
Decápodos , Penaeidae , Contaminantes Químicos del Agua , Masculino , Animales , Humanos , Femenino , Plásticos , Microplásticos , Bahías , Polietileno , Monitoreo del Ambiente
4.
Front Big Data ; 6: 1296469, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38107765

RESUMEN

Introduction: Big graphs like social network user interactions and customer rating matrices require significant computing resources to maintain. Data owners are now using public cloud resources for storage and computing elasticity. However, existing solutions do not fully address the privacy and ownership protection needs of the key involved parties: data contributors and the data owner who collects data from contributors. Methods: We propose a Trusted Execution Environment (TEE) based solution: TEE-Graph for graph spectral analysis of outsourced graphs in the cloud. TEEs are new CPU features that can enable much more efficient confidential computing solutions than traditional software-based cryptographic ones. Our approach has several unique contributions compared to existing confidential graph analysis approaches. (1) It utilizes the unique TEE properties to ensure contributors' new privacy needs, e.g., the right of revocation for shared data. (2) It implements efficient access-pattern protection with a differentially private data encoding method. And (3) it implements TEE-based special analysis algorithms: the Lanczos method and the Nystrom method for efficiently handling big graphs and protecting confidentiality from compromised cloud providers. Results: The TEE-Graph approach is much more efficient than software crypto approaches and also immune to access-pattern-based attacks. Compared with the best-known software crypto approach for graph spectral analysis, PrivateGraph, we have seen that TEE-Graph has 103-105 times lower computation, storage, and communication costs. Furthermore, the proposed access-pattern protection method incurs only about 10%-25% of the overall computation cost. Discussion: Our experimentation showed that TEE-Graph performs significantly better and has lower costs than typical software approaches. It also addresses the unique ownership and access-pattern issues that other TEE-related graph analytics approaches have not sufficiently studied. The proposed approach can be extended to other graph analytics problems with strong ownership and access-pattern protection.

5.
Plants (Basel) ; 12(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37653901

RESUMEN

Mungbean [Vigna radiata (L.) Wilczek] is an important food, feed, and cash crop in rice-based agricultural ecosystems in Southeast Asia and other continents. It has the potential to enhance livelihoods due to its palatability, nutritional content, and digestibility. We evaluated 166 diverse mungbean genotypes in two seasons using multivariate and multi-traits index approaches to identify superior genotypes. The total Shannon diversity index (SDI) for qualitative traits ranged from moderate for terminal leaflet shape (0.592) to high for seed colour (1.279). The analysis of variances (ANOVA) indicated a highly significant difference across the genotypes for most of the studied traits. Descriptive analyses showed high diversity among genotypes for all morphological traits. Six components with eigen values larger than one contributed 76.50% of the variability in the principal component analysis (PCA). The first three PCs accounted for the maximum 29.90%, 15.70%, and 11.20% of the total variances, respectively. Yield per plant, pod weight, hundred seed weight, pod length, days to maturity, pods per plant, harvest index, biological yield per plant, and pod per cluster contributed more to PC1 and PC2 and showed a positive association and positive direct effect on seed yield. The genotypes were grouped into seven clusters with the maximum in cluster II (34) and the minimum in cluster VII (10) along with a range of intra-cluster and inter-cluster distances of 5.15 (cluster II) to 3.60 (cluster VII) and 9.53 (between clusters II and VI) to 4.88 (clusters I and VII), suggesting extreme divergence and the possibility for use in hybridization and selection. Cluster III showed the highest yield and yield-related traits. Yield per plant positively and significantly correlated with pod traits and hundred seed weight. Depending on the multi-trait stability index (MTSI), clusters I, III, and VII might be utilized as parents in the hybridization program to generate high-yielding, disease-resistant, and small-seeded mungbean. Based on all multivariate-approaches, G45, G5, G22, G55, G143, G144, G87, G138, G110, G133, and G120 may be considered as the best parents for further breeding programs.

7.
Heliyon ; 9(4): e14587, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37035360

RESUMEN

Microplastics (MPs) are prevalent in nature due to the proliferation of plastic in the environment. However, the presence of microplastics in lakes is largely unknown in comparison to other aquatic bodies. This study was performed to evaluate the abundance and characteristics of MPs in water, sediment, and fish from three major urban lakes in Dhaka, Bangladesh, namely Dhanmondi, Gulshan, and Hatir Jheel lake. The highest concentrations of microplastics in surface water (36 items/L), sediment (67 items/kg), fish (17 items/individual), and the gastrointestinal tract (4.88 items/gm) were observed. Highest abundance of microplastic in an individual fish was observed in Oreochromis mossambicus from Dhanmondi Lake. The samples were visually examined using stereomicroscope and SEM, which revealed that films were the most prevalent kind of microplastics in both the water and the sediment samples, whereas pellets and foams predominated in the fish samples. Visual observation also revealed MPs dominated by <100 µm in size and transparent in color. According to the Fourier Transform Infrared (FTIR) analysis, the dominant polymers in the analyzed samples were high-density polyethylene, low-density polyethylene, ethylene vinyl acetate, polyvinyl chloride, polycarbonate, cellulose acetate, and polypropylene. MPs were relatively higher in the water and sediment samples of Gulshan Lake, and fish samples of Dhanmondi Lake. The results of this study indicate that microplastic contamination has occurred not only in the water and sediment but also in the inhabitant fishes of the lakes. However, it is discovered that the microplastic intake of fish was significantly related to body weight and length. The implication of the finding suggests that the presence of MPs in urban lakes has raised concerns about the potential human health impact.

8.
Heliyon ; 9(3): e14559, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36967872

RESUMEN

Quantification of streamflow chatacteristics is considered crucial for designing effective management practices in a watershed. Sangu and Matamuhuri are two major rivers of Chittagong Hill Tracts (CHT's) and main sources of upland freshwater inflows to the south-eastern part of Bangladesh. This study was performed to evaluate the streamflow characteristics of Sangu-Matamuhuri watershed based on 25 years historical observed streamflow and rainfall records. Mean daily discharge data recorded by Bangladesh Water Development Board were collected and analyzed for the period of 1995-2019. Stream flow characteristics were determined in terms of different parameters including mean annual runoff discharge, specific water yield, run-off ratio, peak flow, seasonal flow and flow duration. Various statistical measures including mean, standard deviation, co-efficient of variation, lag-1 serial correlation, Mann Kendall test and Sen's slope estimator were applied to justify these parameters. The mean annual runoff discharges of 2167.77 and 1490.61 million cubic meters (mcm) were measured at the gaging stations at Sangu and Matamuhuri watershed, respectively. Matamuhuri basin showed higher value of specific water yield (1.52 mcm/sq. km) compared to the Sangu basin (1.02 mcm/sq. km). The average annual runoff coefficient value of Sangu watershed was found 0.36 while in case of Matamuhuri watershed it was about 0.49. The mean annual peak discharges of 25 years were found 607.63 m3s-1 and 628.42 m3 s-1 at Sangu and Matamuhuri watershed, respectively. Mann-Kendall Test (MK) and Sen's Slope Estimator method were applied for temporal trend analysis. An increasing trend in runoff observed during wet season which may cause flash floods and a decreasing trend observed during dry season that may cause water scarcity in Sangu-Matamuhuri watershed area. Flow duration curves based on 25 years' hydrological data were developed which showed progressive reduction in flows over time in both the watersheds for three periods 1995-2002, 2003-2010 and 2011-2019 with major changes occurred in Matamuhuri watershed during 2011-2020 which might be due to the impact of land use and land cover changes as well as changes in precipitation pattern. Implications of these findings indicate baseline information that can be used to evaluate the impacts of land use changes and climate change, and thereby may facilitate the planning and local management of water resources in the long term.

9.
Biol Trace Elem Res ; 201(6): 3031-3049, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35931926

RESUMEN

Aquatic ecosystems are exceedingly contrived due to industrial dispenses, as a huge amount of toxicants especially heavy metals are released, causing drastic effects on aquatic lives and the human body. This study was performed to assess the quality of point-source industrial wastewater at varying percentage levels and their subsequent hazardous effect on fish (Anabas cobojius) and human health. The perceived value revealed that water quality parameters declined with the increase of wastewater concentration and trace metal evaluation index (TEI) ascertained a high level of water pollution due to Cr, Mn, Fe, Co, Ni, Cu, Zn, and As content for all percentages of wastewater. Concentration of wastewater and culture treatment duration largely impacted on fish mortality rate, body dis-pigmentation, mucus secretion rate, coagulation of mucus all over the body, and accumulation of heavy metals by fish samples. Metal pollution index (MPI) indicated low contamination of fish by the measured elements. Zn and Hg exceeded the threshold limit of target hazard quotient (THQ > 1) and contributed significantly to non-carcinogenic health implications for both the population group. Maximum hazard index in adults and children was observed to be 10.638 and 16.548 for 100% effluent at 96-h exposure period and the overall HI value manifested a very high to medium significant health effects regardless of age. Carcinogen Pb showed insignificant risk but Cr and Ni showed extremely high to medium-high risk for both the population group, and children were found more vulnerable receptors than adults. However, source of heavy metals in wastewater and fish samples stipulated anthropogenic sources.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Adulto , Niño , Animales , Humanos , Aguas Residuales/toxicidad , Ecosistema , Monitoreo del Ambiente , Medición de Riesgo , Metales Pesados/toxicidad , Metales Pesados/análisis , Calidad del Agua , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
10.
Sci Rep ; 12(1): 14800, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042276

RESUMEN

It is essential to predict the mining-induced subsidence for sustainable mine management. The maximum observed subsidence having a noticeable areal extent due to Northern Upper Panels (NUP) and Southern Lower Panels (SLP) at the Barapukuria longwall coal mine is 5.8 m and 4.2 m, respectively, after the extraction of a 10 m thick coal seam. The mining-induced subsidence was simulated by the Displacement Discontinuity Method. The numerical model considered the effects of the ground surface, mining panels, faults, and the dyke. The predicted and the observed subsidence due to the mining of NUP and SLP were compared by varying Young's modulus, and the 0.10 GPa Young's modulus was found to be the best match in the geo-environmental condition. The effects of the faults and the dyke in the calculation were negligible. Future subsidence was predicted by considering 30 m extraction of the thick coal seam as 15.7-17.5 m in NUP and 8.7-10.5 m in SLP. The vulnerable areas demarcated considering the tilt angle and extensile strain might extend up to the coal mine office area and some villages.


Asunto(s)
Minas de Carbón , Bangladesh , Carbón Mineral , Minas de Carbón/métodos
11.
Int J Surg Case Rep ; 93: 106946, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35318186

RESUMEN

Synthetic sub-urethral sling has become the most widely used technique for the surgical management of stress urinary incontinence. Despite a higher success rate, complications like migration, encrustation, and stone formation have been reported by a mid-urethral sling (MUS). Among mid-urethral sling procedures, mini vaginal tape (MVT) is very popular. As periurethral stone formation and urethrovaginal fistula are very uncommon after MVT, case report on this issue is sparse. The current case report features a 55-year female presented with lower abdominal pain and continuous urinary incontinence, 10 years after the MVT. She was diagnosed as a case of periurethral stone with urinary incontinence due to urethro-vaginal fistula. Our surgical team successfully removed the stone formed by the encrustation of the displaced tape and repaired the fistula. Following the MVT, a high degree of suspicion and long-term follow-up is mandatory for the diagnosis and management of these rare complications.

12.
Nanomaterials (Basel) ; 11(8)2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34443700

RESUMEN

Organophosphate (OP) compounds, a family of highly hazardous chemical compounds included in nerve agents and pesticides, have been linked to more than 250,000 annual deaths connected to various chronic diseases. However, a solid-state sensing system that is able to be integrated into a clothing system is rare in the literature. This study aims to develop a nanofiber-based solid-state polymeric material as a soft sensor to detect OP compounds present in the environment. Esters of polydiacetylene were synthesized and incorporated into a cellulose acetate nanocomposite fibrous assembly developed with an electrospinning technique, which was then hydrolyzed to generate more hydroxyl groups for OP binding. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), Instron® tensile tester, contact angle analyzer, and UV-Vis spectroscopy were employed for characterizations. Upon hydrolysis, polydiacetylene esters in the cellulosic fiber matrix were found unaffected by hydrolysis treatment, which made the composites suitable for OP sensing. Furthermore, the nanofibrous (NF) composites exhibited tensile properties suitable to be used as a textile material. Finally, the NF composites exhibited colorimetric sensing of OP, which is visible to the naked eye. This research is a landmark study toward the development of OP sensing in a protective clothing system.

13.
Heliyon ; 7(7): e07487, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34307938

RESUMEN

Proper assessment of reference evapotranspiration (ET 0 ) is necessary for pastoral activity and water management. The Penman-Monteith FAO56 (ET pmf ) method has been recommended as the identical ET 0 estimation model; nonetheless, it belongs to a vast climatic data requirement. There is an urgent need to discover an ideal alternate model for evaluating ET 0 in particular places where all climatic data is insufficient. The performances of 15 empirical models were assessed to get the best alternative model by comparing it with the PMF-56 model. These 15 models were evaluated by employing a daily scatter plot and three well known numerical approaches: relative root-mean-square error, mean absolute error and Nash-Sutcliffe coefficient in this study. Furthermore, a linear regression model was implemented to calibrate and validate the empirical models' performances throughout the 1981-2005 and 2006-2018 time intervals, separately. The outcomes displayed that the ET pmf rose primarily and declined later on a monthly period with the topmost amount in April and the lowermost amount in January. Overall, the Abtew model was the best alternate method showing the highest determination coefficient values more than 0.85 from January to December. In contrast, the Penman, WMO, Trabert, Valiantzas1, Valiantzas2, Valiantzas3 and Jensen-Haise models presented moderate performances with fewer inaccuracies. Afterwards, modification, the version of the above-described models every month has been upgraded deliberately related to actual. The Abtew model had simplicity in the computation process, only used maximum temperature and solar radiation data and linearly well connected to the PMF-56 model.

14.
Acta Biomater ; 131: 493-507, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34139367

RESUMEN

This study first reports the development of a smart drug delivery system (DDS) for multimodal synergistic cancer therapy combining chemo-photothermal-starvation approaches. A magnetic photothermal agent was synthesized by preparing iron oxide (IO) nanoparticles (NPs) with covalently attached indocyanine green (ICG) and glucose oxidase (GOx) (ICGOx@IO). Synthesized ICGOx@IO NPs were co-encapsulated with doxorubicin (Dox) and EGCG ((-)-epigallocatechin-3-gallate) inside PLGA (poly(lactic-co-glycolic acid)) NPs using multiple emulsion solvent evaporation method. Such formulation gave the advantage of triggered drug release by near-infrared (NIR) laser irradiation (808 nm at 1 W/cm2). RGD peptide was attached to the surface of PLGA NPs and the final hydrodynamic size was around 210 nm. Dual targeting by peptide and 240 mT external magnet significantly improved cellular uptake. Cellular uptake was observed using FACS, electron and optical microscopy. Dual targeting along with laser irradiation could reduce in vitro cell viability by 90 ± 2% (Dox-equivalent dose: 10 µg/ml) and complete tumor ablation was achieved in vivo due to synergetic therapeutic effect. Another attractive feature of the DDS was the significant reduction of cardiotoxicity of doxorubicin by EGCG. This new platform is thus expected to hold strong promise for future multimodal combination therapy of cancers. STATEMENT OF SIGNIFICANCE: Doxorubicin is one of the most studied and effective chemotherapeutic agents whose application is hindered due to its cardiotoxicity. In this study, we used (-)-Epigallocatechin-3-gallate (EGCG) to overcome that limitation. However, drug delivery to tumor sites with no/minimum accumulation in healthy organs is always challenging. Although peptide-based targeting is very popular, the effectiveness of receptor/ligand binding active targeting is sometimes questioned which motivated us to apply dual targeting approach. Multimodal therapies can exhibit synergistic effects and subsequently reduce the required dose of drug over monotherapy. We aimed to achieve chemo-photothermal-starvation combination therapy in this study and such achievement is yet to be reported. Our developed system also has the advantage of triggered drug release by near-infrared (NIR) laser irradiation.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Neoplasias , Cardiotoxicidad , Línea Celular Tumoral , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Fototerapia
15.
Polymers (Basel) ; 12(9)2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32942521

RESUMEN

This research aims to develop multilayer sandwich-structured electrospun nanofiber (ENF) membranes using biodegradable polymers. Hydrophilic regenerated cellulose (RC) and hydrophobic poly (lactic acid) (PLA)-based novel multilayer sandwich-structures were created by electrospinning on various copper collectors, including copper foil and 30-mesh copper gauzes, to modify the surface roughness for tunable wettability. Different collectors yielded various sizes and morphologies of the fabricated ENFs with different levels of surface roughness. Bead-free thicker fibers were collected on foil collectors. The surface roughness of the fine fibers collected on mesh collectors contributed to an increase in hydrophobicity. An RC-based triple-layered structure showed a contact angle of 48.2°, which is comparable to the contact angle of the single-layer cellulosic fabrics (47.0°). The polar shift of RC membranes on the wetting envelope is indicative of the possibility of tuning the wetting behavior by creating multilayer structures. Wettability can be tuned by creating multilayer sandwich structures consisting of RC and PLA. This study provides an important insight into the manipulation of the wetting behavior of polymeric ENFs in multilayer structures for applications including chemical protective clothing.

16.
Curr Drug Deliv ; 16(4): 272-294, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30674256

RESUMEN

Chitosan is a polycationic natural polymer which is abundant in nature. Chitosan has gained much attention as natural polymer in the biomedical field. The up to date drug delivery as well as the nanotechnology in controlled release of drugs from chitosan nanofibers are focused in this review. Electrospinning is one of the most established and widely used techniques for preparing nanofibers. This method is versatile and efficient for the production of continuous nanofibers. The chitosan-based nanofibers are emerging materials in the arena of biomaterials. Recent studies revealed that various drugs such as antibiotics, chemotherapeutic agents, proteins and anti-inflammatory analgesic drugs were successfully loaded onto electrospun nanofibers. Chitosan nanofibers have several outstanding properties for different significant pharmaceutical applications such as wound dressing, tissue engineering, enzyme immobilization, and drug delivery systems. This review highlights different issues of chitosan nanofibers in drug delivery applications, starting from the preparation of chitosan nanofibers, followed by giving an idea about the biocompatibility and degradation of chitosan nanofibers, then describing how to load the drug into the nanofibers. Finally, the major applications of chitosan nanofibers in drug delivery systems.


Asunto(s)
Analgésicos/química , Antibacterianos/química , Antineoplásicos/química , Quitosano/química , Sistemas de Liberación de Medicamentos , Nanofibras/química , Animales , Humanos , Nanomedicina
17.
Chemosphere ; 195: 702-712, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29289015

RESUMEN

Formalin can be added as preservative to fresh foods to prevent spoilage and extend shelf life. Formalin contains 37-40% formaldehyde, which is classified as carcinogenic to humans. To assess the public health risk associated with formaldehyde exposure in freshwater fish in Southern Bangladesh, formaldehyde concentrations (mg/kg) were determined in tilapia, Indian major carp rui, Chinese carp and a minor carp from local market and in laboratory simulations (0.5, 1.0, 2.0 and 4.0% formaldehyde solution for 5, 15, 30 and 60 min) with spectrophotometric and high performance liquid chromatography (HPLC) methods. A food frequency questionnaire was used to collect fish consumption (kg/kg BW. d) data from 400 respondents. A probabilistic exposure assessment was conducted using @Risk®7.0 software. Fish treated with formalin at increasing concentrations and exposure time showed increased trends of formaldehyde acquisition irrespective of fish species and analytical methods used (p < .05). Compared to spectrophotometry, the HPLC method was shown to be more sensitive and is therefore the preferred method for formalin quantification. Maximum exposure to formaldehyde (0.28 mg/kg BW. d) was calculated for tilapia using HPLC analysis. Margin of exposure (MoE) provides high priority (<10,000) for tilapia and Indian major carp rui at P99 under spectrophotometric analysis whereas as determined using HPLC, tilapia had MoE values much lower than 10,000 at P99, P95 and P90 (both total population and consumers). Exposure to formaldehyde associated with freshwater fish consumption is a public health concern in Southern Bangladesh and needs further assessment and risk management strategies.


Asunto(s)
Carcinógenos/análisis , Contaminación de Alimentos/análisis , Formaldehído/efectos adversos , Formaldehído/análisis , Hipersensibilidad Respiratoria/prevención & control , Alimentos Marinos/análisis , Animales , Bangladesh , Carpas , Cromatografía Líquida de Alta Presión , Peces , Conservación de Alimentos/métodos , Formaldehído/toxicidad , Humanos , Encuestas y Cuestionarios , Tilapia
19.
Carbohydr Polym ; 162: 115-120, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28224888

RESUMEN

Nanocrystalline cellulose (NCC) was isolated from oil palm empty fruit bunch pulp (EFBP) using ultrasound assisted acid hydrolysis. The obtained NCC was analysed using FESEM, XRD, FTIR, and TGA, and compared with raw empty fruit bunch fibre (REFB), empty fruit bunch pulp (EFBP), and treated empty fruit bunch pulp (TEFBP). Based on FESEM analysis, it was found that NCC has a spherical shaped after acid hydrolysis with the assistance of ultrasound. This situation was different compared to previous studies that obtained rod-like shaped of NCC. Furthermore, the crystallinity of NCC is higher compared to REFB and EFBP. According to thermal stability, the NCC obtained shows remarkable sign of high thermal stability compared to REFB and EFBP.


Asunto(s)
Arecaceae/química , Celulosa/química , Frutas/química , Hidrólisis
20.
ACS Omega ; 2(10): 7334-7342, 2017 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30023547

RESUMEN

Polydiacetylenes (PDAs) are conjugative polymers that demonstrate color changes as a response to an external stimulus. In this study, 10,12-pentacosadiynoic acid (PCDA) was mixed with a supporting polymer including poly(ethylene oxide) (PEO) and polyurethane (PU), and the mixture solution was electrospun to construct fiber composites. The electrospun fibers were then photopolymerized using UV irradiation to produce PEO-PDA and PU-PDA nanofiber mats with a fiber diameter ranging from 130 nm to 2.5 µm. The morphologies of both PEO-PDA and PU-PDA nanofibers were dependent on electrospinning parameters such as the ratio of PCDA to PEO or PCDA to PU and the total polymer concentrations. Scanning electron microscopy images showed beaded fibers of PEO-PDA and PU-PDA at 2 and 18 w/v % concentrations, respectively. Smooth fibers were found when the solvent concentration was increased to 3.75 w/v % in PEO-PDA and 25 w/v % in PU-PDA fibers. Both PEO-PDA and PU-PDA nanofiber composites demonstrated excellent colorimetric responses to the presence of Escherichia coli ATCC25922 bacterial cells and the changes in pH as external stimuli. The nanofibers underwent a rapid colorimetric response when exposed directly to E. coli ATCC25922 grown on Luria-Bertani agar. The comparison between the PEO-PDA and PU-PDA suggested that the combination of PEO and PDA is favorable because it provides a sensitive response to the presence of E. coli. The results were compared with samples of a PDA polymer in the absence of a matrix polymer. The colorimetric response was similar when the PDA polymer and the PDA nanofiber composites were exposed to pH changes, and the color change was found to occur at pH 10 and enhanced at pH 11-13. The PDA-containing nanofiber composites showed stronger colorimetric responses than those of the PDA polymer only, suggesting their potential as biosensors and chemosensors.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...