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1.
Phys Eng Sci Med ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38805105

RESUMO

Electron beam dosimetry is sensitive to the surface contour of the patient. Over 10% difference between Treatment Planning System (TPS) and independent monitor-unit (IMU) calculations have been reported in the literature. Similar results were observed in our clinic between Radformation ClearCalc IMU and Eclipse TPS electron Monte Carlo (eMC) algorithm (v.16.1). This paper presents data measured under 3D printed spherical and cylindrical phantoms to validate the eMC algorithm in the presence of curved geometries. Measurements were performed with multiple detectors and compared to calculations made in Eclipse for the 6, 9 and 12 MeV electron energies. This data is used to create curvature correction factors (CCFs), defined as the ratio of the detector reading with the curved-surface phantom to a flat phantom at the same depth. The mean difference between the TPS calculated and measured CCFs using the NACP, Diode E, microSilicon, and microDiamond detectors were 1.3, 0.9, 0.7 and 0.7% respectively, with maximum differences of 4.5, 2.3, 1.9, and 1.8% respectively. Applying CCFs to previous failing patient IMU calculations improved agreement to the TPS. CCFs were implemented in our clinic for patient-specific IMU calculations with the assistance of a ESAPI script.

2.
Technol Cancer Res Treat ; 23: 15330338241239144, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38515394

RESUMO

Background: This review investigates peripheral dose levels in electron beam treatments, comparing different manufacturers including Varian, Elekta, and Siemens. Accurate measurement of peripheral dose is vital for patient safety and precise radiation delivery in radiation therapy. Methods: This review followed PRISMA standards, conducting a comprehensive literature search from 1978 to July 2023. Emphasis was on identifying studies analyzing peripheral doses related to various electron beam energies, beam angle, field sizes, cutouts, and applicator combinations. Three major databases including PubMed, Web of Science, and Scopus were searched. Results: A total of 7 articles were included in this review. Strategies such as bolus materials, personalized cutouts, and optimal treatment procedures have all been developed to reduce peripheral radiation exposure and enhance patient safety. Ongoing research in this field is focused on further minimizing the risks associated with out-of-field radiation by improving dose delivery systems. Conclusion: The literature emphasizes importance of precision in electron beam radiation therapy, highlighting the critical need for managing peripheral doses and optimizing hardware to ensure patient safety. It advocates for the use of advanced tools and protocols to maintain a balance between effective treatment while protecting healthy tissues. Continuous research, careful treatment planning, and effective management of peripheral doses are essential.


Assuntos
Elétrons , Planejamento da Radioterapia Assistida por Computador , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Imagens de Fantasmas , Aceleradores de Partículas
3.
Front Plant Sci ; 13: 916845, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968099

RESUMO

Cultivated sunflower holds a very narrow genetic base and the efficient utilization of available genetic diversity is very important for a successful breeding program. In the present study, 109 sunflower genotypes were assessed for diversity paneling through a combined approach of morphological and molecular markers analysis. Morphological parameters including days to flower initiation, days to flower completion, plant height, stem curvature, number of leaves per plant, leaf area, head diameter, hundred seed weight, and seed yield per plant were studied. Simple sequence repeats (40 DNA markers) were deployed for diversity profiling. Data were analyzed by both univariate and multivariate statistics. SD and coefficient of variation confirm the presence of significant amounts of genetic variation for all the morphological parameters. Cluster Analysis and Principal Component Analysis further confirm the presence of distinct grouping patterns in the studied material. Cluster analysis of both morphological and molecular analysis revealed that restorer lines tend to group separately from A, B, and open-pollinated lines. Further grouping, at the sub-cluster level, revealed six distinct sub-clusters in each of the two major clusters. In total, 12 genotypes, 6 CMS lines (CMS-HAP-12, CMS-HAP-54, CMS-HAP-56, CMS-HAP-99, CMS-HAP-111, and CMS-HAP-112) and 6 restorer lines (RHP-38, RHP-41, RHP-53, RHP-68, RHP-69, and RHP-71) could be used as potential parents for hybrid development. As genotypes of similar genetic backgrounds tend to group closer, it is deduced that one genotype with the highest seed yield per plant could be used for further hybrid breeding programs in sunflowers.

4.
J Environ Manage ; 319: 115728, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35982553

RESUMO

Pulp and paper mill biomass boilers generate large quantities of ash in Canada with British Columbia (BC) being the highest ash generating province followed closely by Quebec. Generally, the generated ash is landfilled, particularly in BC, with only a small amount being used beneficially. It is anticipated that the difficulty associated with the management of ash will worsen over time as the industry increases its reliance on green fuel. Thus, there is a strong need to identify beneficial uses of pulp and paper boiler ash for the sake of environmental and economic sustainability. The purpose of this report is to provide the first step in this direction, a review of proposed or implemented uses for coal and hog (or wood) ash around the world. Considering both the properties of the ash and local opportunities, this could be the first step toward screening the applications that may apply to individual mills. Several large-scale practices use ash, such as land application (as a nutrient source or as a liming agent), use in the construction industry (as a replacement for cement or as a fill material), and reclamation of mine sites and stabilization of unpaved forest roads. In some cases, relatively small-scale applications have been used which included uses such as a compost component, agent for pH adjustment of liquid streams and slurries, blasting abrasive, and source of quartz for glass manufacturing to name a few. It is important to note that the chemical nature of both fly and bottom ashes can be quite variable due to the type of wood residues combusted as well as combustion equipment used and must be considered in identifying beneficial applications.


Assuntos
Cinza de Carvão , Indústria da Construção , Biomassa , Colúmbia Britânica , Cinza de Carvão/química , Madeira/química
5.
Waste Manag ; 141: 282-289, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35180510

RESUMO

Despite being a wood-derived biomaterial, wood ash generated by Canadian pulp paper mills (PPM) is generally landfilled. This is mainly because of the heterogeneous nature of ash, variations in ash quality and differences in the requirement of ash applications. Unlike limited past work on ash analysis for environmental compliance purposes for specific mills, a comprehensive database of ash quality for the PPM has been developed. Samples of three ash streams, bottom ash (BA), multiclone ash and electrostatic precipitator (ESP) ash, were collected. They were analyzed for physical, chemical and engineering properties of relevance to potential ash uses in areas such as the construction industry, compost production, soil amendment and waste stabilization/ solidification. Results show that the ash quality varied widely from one mill to another. Even within a mill individual ash streams varied substantially in properties. For example, the unburned carbon, a unique parameter for wood ash, in multiclone ash could be over twice the amount in the ESP ash. It is suggested that the traditional definition of fly ash (FA) could be refined to multiclone ash and ESP (or baghouse) ash thereby promoting the source segregation concept for the various ash streams produced at a mill. It is believed that the ash segregation approach, whereby ash sub-streams are kept separate to preserve their quality for specific uses, will minimize heterogeneity and quality variations of ash. This study will not only help divert wood ash away from landfills in favour of beneficial applications but also reduce carbon footprint of a mill.


Assuntos
Cinza de Carvão , Solo , Canadá , Carbono , Cinza de Carvão/química , Rios
6.
Food Sci Nutr ; 9(5): 2605-2611, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34029360

RESUMO

The current investigation was performed to explore the nutritional and functional composition of four landlines of barley denoted as LB1 (Gilgit), LB2 (Nagar), LB3 (Skardu), and LB4 (Shigar) from different regions of Gilgit-Baltistan. The samples were examined for nutritional profile and antioxidant attributes. Total phenolic values and total flavonoid results were in the range of 1.2 to 3.1 mg/g and 0.41 to 0.55 mg/g, respectively. Nutritional profile as crude starch, fiber, protein, ash, and fat ranged from 56.3%-50.80%, 16.50%-11.73%, 16.20%-11.53%, 2.8%-2.1%, and 2.63%-1.63%, respectively. The mineral composition in terms of Mg (527-616 mg/kg) was higher in the landlines followed by Ca (312-368 mg/kg), Na (122.6-146.6 mg/kg), Fe (43.3-65.6 mg/kg), and Zn (22.5-26.6 mg/kg). It was concluded that the indigenous barley landlines had immense nutritional potential and functional attributes. Thus, it can be used for value-added food products and the development of cottage industry in the region.

7.
BJR Open ; 2(1): 20190045, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178966

RESUMO

OBJECTIVE: Preclinical animal models allow testing and refinement of novel therapeutic strategies. The most common preclinical animal irradiators are fixed source cabinet irradiators, which are vastly inferior to clinical linear accelerators capable of delivering highly conformal and precise treatments. The purpose of this study was to design, manufacture and test an irradiation jig (small animal focal irradiation jig, SARJ) that would enable focal irradiation of subcutaneous tumours in a standard fixed source cabinet irradiator. METHODS AND MATERIALS: A lead shielded SARJ was designed to rotate animal holders about the longitudinal axis and slide vertically from the base plate. Radiation dosimetry was undertaken using the built-in ion chamber and GAFChromic RTQA2 and EBT-XD films. Treatment effectiveness was determined by irradiating mice with subcutaneous melanoma lesions using a dose of 36 Gy in three fractions (12 Gy x 3) over three consecutive days. RESULTS: The SARJ was tested for X-ray shielding effectiveness, verification of dose rate, total dose delivered to tumour and dose uniformity. Accurate and uniform delivery of X-ray dose was achieved. X-ray doses were limited to the tumour site when animal holders were rotated around their longitudinal axis to 15o and 195o, allowing sequential dose delivery using parallel-opposed tangential beams. Irradiation of subcutaneous melanoma tumour established on the flanks of mice showed regression. CONCLUSION: SARJ enabled delivery of tangential parallel-opposed radiation beams to subcutaneous tumours in up to five mice simultaneously. SARJ allowed high throughput testing of clinically relevant dose delivery using a standard cabinet-style fixed source irradiator. ADVANCES IN KNOWLEDGE: A custom designed jig has been manufactured to fit into conventional cabinet irradiators and is dosimetrically validated to deliver clinically relevant dose distributions to subcutaneous tumours in mice for preclinical studies.

8.
Food Sci. Technol (SBCTA, Impr.) ; 38(1): 120-125, Jan.-Mar. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-892248

RESUMO

Abstract Flatulence and fullness of stomach is one of the most common problem associated with chickpea primary due to presence of some oligosaccharides and phenols. In this investigation Desi and Kabuli varieties were compared for these oligosaccharides and phenolic compounds. Furthermore, the effect of different processing and cooking methods such as soaking, cooking and germination in the reduction of these antiphysiological factors were are also studies. Maximum tannic acid (0.90 ± 0.20%) was observed in Parbat and C-44 while minimum (0.60 ± 0.04%) in Karak-2. Stachyose contents ranged between 1.10 ± 0.05 (Karak-3) to 1.42 ± 0.02% (Parbat) while raffinose was 0.63 ± 0.05(Karak-3) to 0.81 ± 0.02% (Dasht). The highest tannic acid content was reduced up to 50% in C-44 by cooking of 72 hours germinated seeds. Stachyose and raffinose contents were completely removed after 72 hours germination. Present studies revealed that cooking after germination is the most effective method to reduce the anti-nutritional factors of chickpea. Individually, soaking and cooking also contributed to the loss of the same factors but to a lesser extent.

9.
J Hand Surg Asian Pac Vol ; 21(3): 374-81, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27595957

RESUMO

BACKGROUND: Patients seeking information and advice on treatment of scaphoid fractures unknowingly confront longstanding medical controversies surrounding the management of this condition. However, there are no studies specifically looking into the quality and reliability of online information on scaphoid fractures. METHODS: We identified 44 unique websites for evaluation using the term "scaphoid fractures". The websites were categorized by type and assessed using the DISCERN score, the Journal of the American Medical Association (JAMA) benchmark criteria and the Health on the net (HON) code. RESULTS: The majority of websites were commercial (n = 13) followed by academic (n = 12). Only seven of the websites were HON certified. The mean DISCERN score was 43.8. Only 4 websites scored 63 or above representing excellent quality with minimal shortcomings but 13 websites scored 38 or below representing poor or very poor quality. The mean JAMA benchmark criteria score was 2.2. The Governmental and Non-Profit Organizations category websites had the highest mean JAMA benchmark score. The websites that displayed the HON-code seal had higher mean DISCERN scores and higher mean JAMA benchmark scores compared to websites that did not display the seal. CONCLUSIONS: Good quality health information is certainly available on the Internet. However, it is not possible to predict with certainty which sites are of higher quality. We suggest clinicians should have a responsibility to educate their patients regarding the unregulated nature of medical information on the internet and proactively provide patients with educational resources and thus help them make smart and informed decisions.


Assuntos
Fraturas Ósseas/terapia , Disseminação de Informação/métodos , Comportamento de Busca de Informação , Internet , Osso Escafoide/lesões , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estados Unidos
10.
Bioorg Chem ; 67: 95-104, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27299811

RESUMO

Two new pregnane glycosides named desmiflavasides C (1) and D (2) were isolated from the sap of Desmidorchis flava (N.E.Br.) Meve & Liede and have had their structures confirmed from 1D and 2D NMR spectroscopic techniques and mass spectrometry (ESIMS). Further, the effects of desmiflavasides C (1) and D (2) on the proliferation of breast and ovarian cancer cells as well as normal breast epithelial cells in culture were examined. Interestingly, desmiflavasides C (1) and D (2) were able to cause a substantial decline in the viability of cancer cells in a concentration-dependent manner. Moreover, treatment of normal cells with compound 2 resulted in no significant growth inhibition, indicating that its cytotoxicity was selective towards cancer cells. Furthermore, the activity of compound 2 against cancer as well as normal epithelial cells was found to be similar to that of a previously reported pregnane glycoside, nizwaside (3). Molecular docking studies of desmiflavasides C (1) and D (2) and nizwaside (3) were carried out to ascertain if it was possible to predict any important binding orientations required of small molecule drug candidates with suggested protein target molecules for the purposes of being able to predict the affinity and activity to an acceptable degree by such compounds. Desmiflavaside D (2) showed a relatively good binding affinity (-22.4449kcal/mol) as compared to the other two compounds viz., nizwaside (3) (-20.0319kcal/mol), and desmiflavaside C (1) (-19.4042kcal/mol). Docking results of the three pregnane glycosides viz., 1-3 revealed that these ligand molecules can accurately interact with the target protein.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apocynaceae/química , Glicosídeos/farmacologia , Simulação de Acoplamento Molecular , Pregnanos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Estrutura Molecular , Pregnanos/química , Pregnanos/isolamento & purificação , Relação Estrutura-Atividade
11.
Molecules ; 20(12): 22645-61, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26694344

RESUMO

The influence of carboxy methyl cellulose (CMC) and guargum-based coatings containing silver nanoparticles was studied on the postharvest storage stability of the kinnow mandarin (Citrus reticulata cv. Blanco) for a period of 120 days (85%-90% relative humidity) at 4 °C and 10 °C. Physicochemical and microbiological qualities were monitored after every 15 days of storage. Overall results revealed an increase in total soluble solid (TSS), total sugars, reducing sugars and weight loss but this increase was comparatively less significant in coated fruits stored at 4 °C. Ascorbic acid, total phenolics, and antioxidant activity was significantly enhanced in coated fruits stored at 4 °C. Titratable acidity significantly decreased during storage except for coated kinnow stored at 4 °C. In control samples stored at 10 °C, high intensity of fruit rotting and no chilling injury was observed. Total aerobic psychrotrophic bacteria and yeast and molds were noticed in all treatments during storage but the growth was not significant in coated fruits at 4 °C. Kinnow fruit can be kept in good quality after coating for four months at 4 °C and for 2 months at 10 °C.


Assuntos
Carboximetilcelulose Sódica/química , Conservação de Alimentos , Frutas/química , Galactanos/química , Mananas/química , Nanopartículas Metálicas/química , Gomas Vegetais/química , Prata/química , Ácido Ascórbico/química , Citrus/química , Embalagem de Alimentos , Armazenamento de Alimentos , Fenóis
12.
Arch Pharm Res ; 38(12): 2137-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26335549

RESUMO

The sap from the succulent Desmidorchis flava (N.E.Br) Meve and Liede yielded a new pregnane glycoside, named nizwaside whose structure was established using 1D and 2D NMR techniques as well as mass spectrometry (ESIMS). Nizwaside was tested for anticancer, DPPH antioxidant, urease enzyme inhibition, α-glucosidase enzyme inhibition and acetylcholinesterase inhibition activities. Interestingly, nizwaside showed significant anti-proliferative effects on MDA MB231 breast cancer cells with an IC(50) of 23.5 µg/ml. Moreover, nizwaside was more effective than Doxorubicin, a well-known clinical anticancer drug, in suppressing MDA MB231 cell proliferation even at concentrations lower than that of Doxorubicin (75 µg/ml nizwaside vs. 100 µg/ml Doxorubicin). On the other hand, nizwaside showed relatively weak antioxidant activity with 15 % inhibition.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apocynaceae , Glicosídeos/química , Glicosídeos/isolamento & purificação , Pregnanos/química , Pregnanos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Feminino , Glicosídeos/farmacologia , Humanos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Pregnanos/farmacologia
13.
Pak J Pharm Sci ; 28(2): 561-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25730789

RESUMO

Lactobacillus bulgaricus is one of the predominant lactic acid bacteria of dahi, conferring technological and functional attributes. In the present study thirty dahi samples were investigated for bacteriocin producing L. bulgaricus. Fourteen different isolates were obtained and five were scrutinized for antibacterial activities against food born pathogens. Amongst, a strain TLB06FT was found to have a wide array of antibacterial activities against Gram positive and negative bacteria was selected for further characterization. Growth media optimization for this strain revealed maximum bacteriocin production on MRS media supplemented with glucose (2%), sodium chloride (1%), Tween-80 (0.5%) and yeast extract (1 %). In addition, optimization of growth conditions revealed maximum bacteriocin production at pH 5.5 and temperature of 30-37°C. Bacteriocin showed thermo stability at 90°C and remained highly active in the pH range of 3.5-7.5, inactive by protein catalyzing enzymes and showed no change in activity (800AumL(-1)) when treated with organic solvents and surfactants. The obtained bacteriocin was purified to 1600AU mL(-1) by ammonium sulfate precipitation (80%) by using dialyzing tubing. In the same way, a single peak was obtained by RP-HPLC having antibacterial activity of 6400AU mL(-1). Thus, wild strains of L. bulgaricus have great potential for the production new and novel type of bacteriocins.


Assuntos
Antibacterianos/biossíntese , Bacteriocinas/biossíntese , Lactobacillus/metabolismo , Bacteriocinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Lactobacillus/crescimento & desenvolvimento
14.
Pak J Pharm Sci ; 28(2): 631-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25730794

RESUMO

ß-sitosterol is a naturally occurring plant sterol (phytosterol) present in many fruits and vegetables. Scientific research has proven that ß-sitosterol is helpful in maintaining the proper functioning of our body. Previously we described the complexation of ß-sitosterol with trace metals (Mahmood et al., 2013). Trace metals after the formation of complex unable to absorb in the body and hence eliminated out from the body thus reducing metal toxicity (Marsha, 1996). The present article describes the complexation of µ-sitosterol with Palladium (Pd) metal. Palladium is a toxic metal and due to polluted and hazardous environment traces of this metal can be transferred into the body, which is harmful for human health. Our aim is to make Pd-sterol complex so that this toxic metal (Pd) does not absorb in the body and hence excreted out from the body in the complex form. In order to form this complex µ-sitosterol (Ib) is reacted with Tris (dibenzylideneacetone) dipalladium or [Pd(2) (DBA)(3)] (Ia) in 2:1 ratio in an inert atmosphere and dimethylformamid (DMF) added as a solvent. The resulting complex [Pd(2) (DBA)(3).(ß-sitosterol) (Ic) was identified by various spectroscopic techniques such as IR, Mass and (1)H-NMR. This new organo metallic complex (Ic) also showed significant antibacterial and antifungal activity. The present work revealed that Pd-sterol complex does not only reduce metal toxicity but also helpful in minimizing bacterial and fungal infections present in the body. Our research also concluded that we must take plenty of fruits and vegetables in our diet so that natural plant sterol such as ß-sitosterol can enhance our defense mechanism and maintain other functions of our body.


Assuntos
Anti-Infecciosos/farmacologia , Compostos Organometálicos/química , Sitosteroides/química , Espectroscopia de Ressonância Magnética , Compostos Organometálicos/farmacologia , Sitosteroides/farmacologia , Espectrofotometria Infravermelho
15.
Ann Saudi Med ; 34(2): 103-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24894777

RESUMO

The liver transplantation program at KFSHRC has been active since 2001. More than 450 liver transplants have been performed so far. The program evolved from adult cadaveric transplant to living donor and recently to pediatric and split techniques. The 1-year survival of patients for both pediatric and adult exceeded 90% and the 5-year survival of patients is more than 80%. Associated with this success are challenges that include: organ shortage, quality of organ harvested, inability to meet the growing national need, increased demand of resource to meet the need of the program, and lack of a collaborative national strategy in organ donation and transplantation.


Assuntos
Transplante de Fígado/mortalidade , Adulto , Criança , Hospitais/normas , Hospitais/estatística & dados numéricos , Humanos , Transplante de Fígado/métodos , Doadores Vivos , Avaliação de Resultados da Assistência ao Paciente , Estudos Retrospectivos , Arábia Saudita
16.
Int J Food Sci Nutr ; 65(5): 582-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24689927

RESUMO

In this study, different strains of Lactobacillus acidophilus from dahi were analyzed for certain probiotic and antibacterial properties. Initially, these strains were confirmed by the amplification of 16S rRNA regions and then screened for antibacterial activities against food borne pathogens. The phenotypic relationship between apparent antibacterial activity and cell wall proteins were established by cluster analysis. It was observed that those strains, which have prominent bands having size 22-25 kDa possess antibacterial activity. On the basis of wide spectrum of killing pattern, a strain LA06FT was further characterized that showed no change in its behavior when subjected to the antibiotic protected environment and grow well in acid-bile conditions. The bacteriocin produced by this strain has specific antibacterial activity of 5369.13 AU mg(-1). It remained stable at 60-90 °C and pH range of 4.5-6.5 while proteolytic enzymes inactivate the bacteriocin that confirm its proteinic nature having molecular weight of ≤8.5 kDa.


Assuntos
Antibacterianos/farmacologia , Laticínios/microbiologia , Lactobacillus acidophilus , Probióticos/administração & dosagem , Bacteriocinas/biossíntese , Bacteriocinas/farmacologia , Análise por Conglomerados , Farmacorresistência Bacteriana , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Peso Molecular , RNA Ribossômico 16S/genética
17.
Int J Food Sci Nutr ; 64(4): 494-501, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23216305

RESUMO

For the isolation of probiotic cultures of Streptococcus thermophilus from dahi, we collected 120 samples from the southern regions of Punjab, Pakistan. Eleven isolates were obtained, and six were scrutinized for antibacterial activities against food-borne pathogens. The carbohydrate fermentation profile of these six strains was determined by the API50 CHL system. Additionally, these strains were amplified for their 16S rRNA regions to confirm their genotypic relationship. Furthermore, phenotypic characteristics among these strains were established by S-layer protein analysis of their cell walls by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and by plasmid profiling. The outer cell wall layers of these strains have 6-14 different sizes of protein bands of 27, 34, 37, 40, 45 and 60 kDa molecular weight. Similarly, except S02FT, all strains have a single prominent plasmid of 23 kbp, whereas S02FT has an additional plasmid of 9 kbp. On the basis of this unique feature and a wide spectrum of killing patterns against pathogenic bacteria, S. thermophilus S02FT was further characterized. This culture showed an optimum antibacterial activity of 800 AU/ml at pH 5.0-5.5 and a temperature of 30-37°C. It grows well in in vitro acidic conditions and tolerates bile salt up to 2% concentration. It was resistant to nalidixic acid, ciprofloxacin, gentamicin and sulphamethoxazol, but showed intermediate behaviour to vancomycin and erythromycin.


Assuntos
Adaptação Fisiológica , Antibacterianos/farmacologia , Dieta , Microbiologia de Alimentos , Interações Microbianas , Probióticos/isolamento & purificação , Streptococcus thermophilus/isolamento & purificação , Ácidos , Ácidos e Sais Biliares , Parede Celular/metabolismo , Carboidratos da Dieta/metabolismo , Resistência a Medicamentos , Fermentação , Genótipo , Humanos , Glicoproteínas de Membrana/metabolismo , Peso Molecular , Paquistão , Fenótipo , Plasmídeos , RNA Ribossômico 16S/genética , Streptococcus thermophilus/genética , Streptococcus thermophilus/crescimento & desenvolvimento , Streptococcus thermophilus/metabolismo
18.
Water Environ Res ; 84(6): 497-505, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22866390

RESUMO

The conventional anaerobic digestion process, requiring long solids retention times (SRTs) to digest solids, is currently viewed as impractical for the pulp and paper industry because of high capital costs associated with the construction of new digesters. Recent developments in sludge solubilization technology could be promising in reducing digester size, which also allows for the potential use of decommissioned tanks, both of which can reduce the capital cost. Three pretreatment technologies for use with anaerobic digestion were tested on laboratory-scale to investigate their feasibility. The SRTs in all three digesters systematically decreased from 20 to 3 days. The reference digester was fed waste activated sludge (WAS) to serve as the control at the same SRTs. The other digesters were fed WAS that had been preconditioned using mechanical shearing, sonication, or high-pressure homogenization technology. Anaerobic digestion with high-pressure homogenization produced as much methane at 3-day mean SRT as that from the reference digester operated at 20-day SRT. Therefore, a new digester can theoretically be 85% smaller than a conventional digester. An added benefit of WAS to methane conversion is the recovery of nutrients nitrogen and phosphorus.


Assuntos
Resíduos Industriais/análise , Papel , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Reatores Biológicos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
19.
Water Environ Res ; 82(5): 440-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20480765

RESUMO

Benthal solids accumulated in aerated stabilization basins (ASBs) must be dredged to regain treatment capacity. While dredging restores treatment performance, it has been associated occasionally with the failure to meet regulatory effluent toxicity limits at the time of dredging. A first study of its kind was undertaken to investigate the implications of ASB dredging on potential effluent toxicity to fish. The study showed that benthal solid slurry removed from the quiescent zone of an ASB with a hydraulic dredge was toxic to rainbow trout with a 96-hour median lethal concentration (LC50) of 2.2%. The high ammonia concentration in the sample was the main cause of fish mortality. Hydrogen sulfide and resin and fatty acids also were present in the dredged material at concentrations that could cause fish mortality. These findings have led to best management practices that can be used to mitigate or eliminate fish toxicity issues during dredging operations.


Assuntos
Resíduos Industriais/efeitos adversos , Oncorhynchus mykiss , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade , Amônia/toxicidade , Animais , Bactérias/metabolismo , Ácidos Graxos/toxicidade , Sulfeto de Hidrogênio/toxicidade , Concentração de Íons de Hidrogênio , Oxigênio/química , Oxigênio/metabolismo , Papel , Resinas Vegetais/toxicidade , Poluição Química da Água/legislação & jurisprudência , Poluição Química da Água/prevenção & controle
20.
Water Res ; 42(10-11): 2411-20, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18433826

RESUMO

Aerated stabilization basins (ASB) accumulate benthal solids as they provide biotreatment to wastewaters. The accumulated solids must digest at a rate that matches the rate of settling of fresh solids in order to maintain the water column depth at the design value. In practice, however, the deposited solids digest at rates much slower than the fresh deposition rates, resulting in solids accumulation in the system. Excessive build-up of solids warrants dredging or abandoning the solids-filled cells in favour of opening new ones, often due to prohibitive dredging costs. An investigating study on factors affecting digestion rate was carried out using benthal solids from a pulp and paper ASB. The rate of digestion was not limited by the lack of macronutrients N, P, and S in the system or by toxicity due to ammonia or sulphide. Oxidation-reduction potential and pH were found conducive to anaerobic digestion throughout the 1120-day study. However, the generation of volatile organic acids from liquefaction/fermentation of solid substrate appeared to be a major factor limiting the digestion rate. Based on laboratory data, operating an ASB in the optimal mesophilic temperature range could be a practical way of enhancing the benthal solids digestion rate.


Assuntos
Eliminação de Resíduos , Aerobiose , Anaerobiose , Gases/metabolismo , Compostos Orgânicos/análise , Oxigênio/metabolismo , Porosidade , Solubilidade , Sulfatos/metabolismo , Temperatura , Fatores de Tempo , Volatilização , Água , Difração de Raios X
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