Toxicity is the totality of adverse effects, which can be functional and morphological lesions in a living organism, caused by a substance introduced in relatively high single doses or in small, repeated doses. The ai...Toxicity is the totality of adverse effects, which can be functional and morphological lesions in a living organism, caused by a substance introduced in relatively high single doses or in small, repeated doses. The aim of this study was to assess the OECD-recommended acute oral toxicity and anti-inflammatory activity of ethanolic extract of Ficus umbellata leaves. Animals were given a single oral dose of 1000, 3000 and 5000 mg/Kg body weight (BW) of the extract. For the anti-inflammatory activity test, rats were given the ethanolic extract of F. umbellata leaves at doses of 100, 300 and 500 mg/Kg or aspirin® at a concentration of 100 mg/Kg PC orally, one hour before injection of 0.05 ml of 1% formalin under the plantar fascia of the rat’s right hind paw. Paw volume measurements were taken one, two and three hours after formalin injection, using an electronic caliper. After 14 days of observation, no deaths were observed in treated rats. The LD50 of ethanolic extract of Ficus umbellata leaf powder is greater than 5000 mg/Kg body weight. This extract has no significant effects on hematological parameters and on the main markers of nephrotoxicity and hepatotoxicity for a single dose of less than 5000 mg/Kg PC. It reduces formalin-induced edema. Evaluation of the percentage inhibition showed that the extract had greater anti-inflammatory activity at 3 hours after the start of the experiment. However, better inhibition of inflammatory oedema of the paw of rats treated with 500 mg/Kg was observed at 5 hours after the start of the experiment, with a percentage inhibition of 69.23 ± 1.02, compared with the reference group treated with aspirin® 100 mg/Kg, which showed an inhibition of 63.50 ± 0.98. These results show that F. umbellata leaves possess anti-inflammatory activity, which would justify their use in traditional African medicine to prevent or treat inflammation.展开更多
Haptoglobin(HP)is a liver glycoprotein that is actively synthesized during in-flammatory and hemolytic processes.It also has pro-oxidant and proinflam-matory properties,which are a function of its genotype.The genetic...Haptoglobin(HP)is a liver glycoprotein that is actively synthesized during in-flammatory and hemolytic processes.It also has pro-oxidant and proinflam-matory properties,which are a function of its genotype.The genetic polymorp-hism of the chains leads to synthesis of three phenotypes/proteins,which are related to the number and type of chains and their molecular weight,namely HP1-1,HP1-2 and HP2-2.Patients with HP2-2 have more vascular complications,while those with HP1-1 have fewer.HP is involved in the worsening of diseases,such as HP2-2 in aggravation of vaso-occlusive crises in sickle cell disease,and worsening of the pathophysiology of other diseases.In contrast,HP1-1 confers better protection against diseases.All of this suggests that further studies should be conducted,including experimental and analytical studies focused on de-monstrating the influence of different HP genotypes on individual clinical and hematological data.This would help in understanding the role played by this genetic polymorphism in the pathophysiology of diseases.展开更多
Introduction: Moringa oleifera was a medicinal plant generally used by populations in the food and therapeutic fields. It’s used to treat anemia has been observed in the Djougou Zone in northern Benin. To our knowled...Introduction: Moringa oleifera was a medicinal plant generally used by populations in the food and therapeutic fields. It’s used to treat anemia has been observed in the Djougou Zone in northern Benin. To our knowledge, there were no scientific data available that have evaluated its efficacy in the treatment of haemolytic anemia. This was what justifies this research work in which the phytochemical analysis, extraction and evaluation of the anti-anemic effect were carried out. Methods: Five groups of five Wistar rats each were formed. All the rats were rendered anemic by injection of phenylhydrazine hydrochloride on the first two days D0 and D1 except those in the negative control group. From the second day, the anemic groups were force-fed either with the aqueous extract of Moringa oleifera leaves at 200 or 300 mg/kg body weight/day, or with vitafer, the reference drug against anemia. The positive control group (anemia) was not treated. Blood samples were taken from all the rats on different days: D0, D2, D7, D10 and D15 to evaluate the data of the hemogram and the osmotic resistance of the red blood cells. Results: Phytochemical analysis revealed the presence of tannins, flavonoids, leucoanthocyanins, saponosides, triterpenes and mucilages. A good yield was obtained at the extraction. Both the extract and the reference drug vitafer completely corrected anemia within two weeks after stimulating hemoglobin synthesis and early release of immature red blood cells into the bloodstream. Its effect seemed dose-dependent and specific. Conclusion: Moringa oleifera leaves showed good therapeutic efficacy and can be considered and exploited for transformation into improved traditional medicines (ITM) in the treatment of anemia.展开更多
AIM: To investigate the impact of agitation speed on pectinase production and morphological changing of Aspergillus niger(A. niger) HFD5A-1 in submerged fermentation. METHODS: A. niger HFM5A-1 was isolated from a rott...AIM: To investigate the impact of agitation speed on pectinase production and morphological changing of Aspergillus niger(A. niger) HFD5A-1 in submerged fermentation. METHODS: A. niger HFM5A-1 was isolated from a rotted pomelo. The inoculum preparation was performed by adding 5.0 m L of sterile distilled water containing 0.1% Tween 80 to a sporulated culture. Cultivation was carried out with inoculated 1 × 107 spores/m L suspension and incubated at 30 ℃ with different agitation speed for 6 d. The samples were withdrawn after 6 d cultivation time and were assayed for pectinase activity and fungal growth determination. The culture broth was filtered through filter paper(Whatman No. 1, London) to separate the fungal mycelium. The cell-free culture filtrate containing the crude enzyme was then assayed for pectinase activity. The biomass was dried at 80 ℃ until constant weight. The fungal cell dry weight was then expressed as g/L. The 6 d old fungal mycelia were harvested from various agitation speed, 0, 50, 100, 150, 200 and 250 rpm. The morphological changing of samples was then viewed under the light microscope and scanning electron microscope.RESULTS: In the present study, agitation speed was found to influence pectinase production in a batch cultivation system. However, higher agitation speeds than the optimal speed(150 rpm) reduced pectinase production which due to shear forces and also collision among the suspended fungal cells in the cultivation medium. Enzyme activity increased with the increasing of agitation speed up to 150 rpm, where it achieved its maximal pectinase activity of 1.559 U/m L. There were significant different(Duncan, P < 0.05) of the pectinase production with the agitation speed at static, 50, 100, 200 and 250 rpm. At the static condition, a well growth mycelial mat was observed on the surface of the cultivation medium and sporulation occurred all over the fungal mycelial mat. However with the increased in agitation speed, the mycelial mat turned slowly to become a single circular pellet. Thus, it was found that agitation speed affected the morphological characteristics of the fungal hyphae/mycelia of A. niger HFD5A-1 by altering their external as well as internal cell structures.CONCLUSION: Exposure to higher shear stress with an increasing agitation speed could result in lower biomass yields as well as pectinase production by A. niger HFD5A-1.展开更多
The objective of this study was designed to evaluate the effects of biostimulation and bioaugmentation amendment agents (NPK fertilizer, Tween 80 and mixed culture) on the bioremediation of tropical soil samples artif...The objective of this study was designed to evaluate the effects of biostimulation and bioaugmentation amendment agents (NPK fertilizer, Tween 80 and mixed culture) on the bioremediation of tropical soil samples artificially contaminated with Weathered Bonny Light Crude Oil (WBLCO). Response Surface Methodology (RSM) with Box Behnken Design (BBD) was used with three levels and three factors of NPK fertilizer (2 - 6 g), Tween 80 (5 - 15 mg/l) and mixed culture (0.5 - 1.5 g/l) as independent variables and WBLCO removal as dependent variable (response) in a six weeks remediation period. The results showed that the rate of WBLCO removal generally increased with increase in the amount of NPK fertilizer, Tween 80 and mixed culture (biomass), respectively. A statistically significant (P < 0.0001) second-order quadratic regression model for WBLCO removal (using design-expert statistical program (v. 6.0.8)) with a coefficient of determination, R (=0.9996) was obtained. Numerical optimization technique based on desirability function was carried out to optimize the bioremediation process. The optimum values for biostimulation and bioaugmentation amendment agents to achieve a predicted maximum WBLCO removal of 84.88 percent were found to be: NPK fertilizer, 4.25 g;Tween 80, 10.22 mg/l and mixed culture, 0.46 g/l. At this optimum point, the observed WBLCO removal was found to be 83.79 percent. The statistical analyses and the closeness of the experimental results and model predictions show the reliability of the regression model and thus, biostimulation and bioaugmentation of indigenous microbial density and activity can reduce remediation period of petroleum hydrocarbon contaminated environment and subsequently the cost of remediation.展开更多
The depletion of world petroleum reserves and the increased environmental concerns have stimulated the search for alternative sources for petroleum based fuel. The possibility of using vegetable oils as fuel has been ...The depletion of world petroleum reserves and the increased environmental concerns have stimulated the search for alternative sources for petroleum based fuel. The possibility of using vegetable oils as fuel has been recognized, however, due to its high viscosities and low volatilities makes it inefficient for most combustion engines and thus the need to get them chemically altered or transesterified to obtain fatty alkyl esters of the oil (biodiesel). In this study, binary and ternary blends of biodiesel were produced and the effect of temperature on their viscosity and density was investigated. Biodiesel was produced from soybean oil by transesterification of the oil with methanol using potassium hydroxide as a catalyst at a temperature of 60℃ in a batch reactor. Binary and ternary blends of the soy-biodiesel were prepared with soy bean oil and petroleum diesel fuel, respectively. Viscosities and densities of the binary and ternary blends were measured at different temperatures of 20℃ to 90℃ as to determine the effect of temperature on viscosities and densities of the blends. The properties of the soy-biodiesel produced were compared with ASTM standard and found to be within the limits. The results show that the viscosities and densities of both the binary and ternary blends are temperature dependent. The viscosities of binary and ternary blends decreased nonlinearly with temperature, while their densities decreased linearly with temperature. The variation of temperature with viscosity and density of the blends was correlated and the polynomial equation offered the best correlation between temperature and viscosity, while linear equation gave the best correlation between temperature and density. In conclusion, the efficiency of binary and ternary blends of biodiesel in combustion engines is dependent on the viscosity and density of the blends which are invariably temperature dependent.展开更多
Hepatitis C virus(HCV) is a major health problem worldwide. Early detection of the infection will help better management of the infected cases. The monoclonal antibodies(m Ab) of mice are predominantly used for the im...Hepatitis C virus(HCV) is a major health problem worldwide. Early detection of the infection will help better management of the infected cases. The monoclonal antibodies(m Ab) of mice are predominantly used for the immunodiagnosis of several viral,bacterial,and parasitic antigens. Serological detection of HCV antigens and antibodies provide simple and rapid methods of detection but lack sensitivity specially in the window phase between the infection and antibody development. Human mA b are used in the immunotherapy of several blood malignancies,such as lymphoma and leukemia,as well as for autoimmune diseases. In this review article,we will discuss methods of mouse and human monoclonal antibody production. We will demonstrate the role of mouse mA b in the detection of HCV antigens as rapid and sensitive immunodiagnostic assays for the detection of HCV,which is a major health problem throughout the world,particularly in Egypt. We will discuss the value of HCV-neutralizing antibodies and their roles in the immunotherapy of HCV infections and in HCV vaccine development. We will also discuss the different mechanisms by which the virus escape the effect of neutralizing mA b. Finally,we will discuss available and new trends to produce antibodies,such as egg yolk-based antibodies(Ig Y),production in transgenic plants,and the synthetic antibody mimics approach.展开更多
Objective:To extract the bioactive compound from Enteromorpha intestinalis(E. intestinalis) and determine its in vitro antimicrobial activity. Methods: E. intestinalis was extracted by methanol and subjected to antimi...Objective:To extract the bioactive compound from Enteromorpha intestinalis(E. intestinalis) and determine its in vitro antimicrobial activity. Methods: E. intestinalis was extracted by methanol and subjected to antimicrobial screening. The antimicrobial activity was studied by using disc diffusion and broth dilution method. The effect of the extract on the growth profile of the bacterial was also examined via time-kill assay. Microscopy observations using SEM was done to determine the major alterations in the microstructure of methicillin-resistant Staphylococcus aureus(MRSA). Results: The results showed methanolic extract of E. intestinalis exhibited a favourable antimicrobial activity against tested bacteria with produced inhibition zone ranging from 8.0-19.0 mm. However, all the tested fungi and yeast were resistant to the extract treatment. Time kill assay suggested that methanolic extract of E. intestinalis had completely inhibited MRSA growth and also exhibited prolonged antibacterial activity. The main abnormalities noted from the microscopic observations were the structural deterioration in the normal morphology and complete collapsed of the bacteria cells after 36 h of treatment. Conclusions: The significant antibacterial activity shown by crude extract suggested its potential against MRSA infection. The extract may have potential to develop as antibacterial agent in pharmaceutical use.展开更多
OBJECTIVE To observe anti-tumor effects of PVAX-PSMA gene vaccine. METHODS The PSMA gene was inserted into a mammalian expression vector, PVAX-1, to construct the DNA vaccine candidate, and was then used to vaccinate ...OBJECTIVE To observe anti-tumor effects of PVAX-PSMA gene vaccine. METHODS The PSMA gene was inserted into a mammalian expression vector, PVAX-1, to construct the DNA vaccine candidate, and was then used to vaccinate C57BL/6 mice. Animals vaccinated with PVAX-1 and NaC1 were used as controls. Anti-PSMA antibody was detected in sera of the animals. The proliferation and cytotoxicity of the spleen cells were observed. The immunized mice were inoculated with RM-1 cells. The mice were inoculated with RM-1 cells, and then the mice were immunized. The anti-tumor efficacy of the gene vaccine was evaluated by the ratio of tumor formation, tumor volume, tumor mass before and after gene vaccination and evaluated by survival rate of the immunized mice. RESULTS High level of anti-PSMA antibody was induced in the PVAX-PSMA group. The splenocytes from PVAX-PSMA group were stimulated to produce strong proliferation responses and significant cytotoxic T-cells (CTL) activity. After the mice were immunized with PVAX-PSMA gene, tumor occurrence was decreased, and the growth velocity of tumor was markedly reduced, resulting in prolonged tumor-free time (P 〈 0.05). CONCLUSION PVAX-PSMA gene vaccine has significant anti- tumor effects and provides an experimental basis for primary prevention and immunotherapy of prostate cancer.展开更多
The H9N2 subtype avian influenza virus(AIV)inactivated vaccine has been used extensively in poultry farms,but it often fails to stimulate a sufficiently high immune response in poultry in the field,although it works w...The H9N2 subtype avian influenza virus(AIV)inactivated vaccine has been used extensively in poultry farms,but it often fails to stimulate a sufficiently high immune response in poultry in the field,although it works well in laboratory experiments;hence,the virus still causes economic damage every year and poses a potential threat to public health.Based on surveillance data collected in the field,we found that broilers with high levels of maternal-derived antibodies(MDAs)against H9N2 virus did not produce high levels of antibodies after vaccination with a commercial H9N2 inactivated vaccine.In contrast,specific pathogen-free(SPF)chickens without MDAs responded efficiently to that vaccination.When MDAs were mimicked by administering passively transferred antibodies(PTAs)into SPF chickens in the laboratory,similar results were observed:H9N2-specific PTAs inhibited humoral immunity against the H9N2 inactivated vaccine,suggesting that H9N2-specific MDAs might hinder the generation of antibodies when H9N2 inactivated vaccine was used.After challenge with homologous H9N2 virus,the virus was detected in oropharyngeal swabs of the vaccinated and unvaccinated chickens with PTAs but not in the vaccinated chickens without PTAs,indicating that H9N2-specific MDAs were indeed one of the reasons for H9N2 inactivated vaccine failure in the field.When different titers of PTAs were used to mimic MDAs in SPF chickens,high(HI=12 log2)and medium(HI=log 9 log2)titers of PTAs reduced the generation of H9N2-specific antibodies after the first vaccination,but a booster dose would induce a high and faster humoral immune response even of PTA interference.This study strongly suggested that high or medium titers of MDAs might explain H9N2 inactivated vaccine failure in the field.展开更多
The use of natural hydrogels in agriculture provides solutions to many problems without threatening the environment. This study aims to evaluate the potential impact of environmentally friendly hydrogels (pectin, star...The use of natural hydrogels in agriculture provides solutions to many problems without threatening the environment. This study aims to evaluate the potential impact of environmentally friendly hydrogels (pectin, starch and pectin + starch) in reducing the negative effects of drought stress on tomato yield and quality. Two different peels (orange peel and banana peel) are used to prepare environmentally friendly hydrogels. The water retention efficiency of hydrogels has been studied. Greenhouse experiment for tomato under drought stress was conducted during 2019. These hydrogels were used under several level of irrigation (100%, 75%, and 50% FC), soil without hydrogel was used as a control. The results showed that the eco-friendly hydrogels (starch, pectin, and pectin + starch) had capacity retention of water for a long time. The obtained data from the greenhouse experiment showed that the eco-friendly hydrogel showed a positive effect on retention of water and increase the soil moisture content compared to control. The highest increase was observed at pectin + starch treatment. This increase reached to 2.8-, 2.4- and 2.0-fold for 100%, 75% and 50% FC compared to the control. Eco-</span></span></span></span><span><span><span><span><span style="font-family:""> </span></span></span></span></span><span><span><span><span><span style="font-family:"">friendly hydrogel application under different drought conditions led to improve yield and quality of tomato fruits. Moreover, conversion of agricultural wastes to hydrogels and the use of these eco-friendly materials instead of synthetic hydrogels are necessary to utilize the limited natural resources and decrease the harmful impact of agricultural wastes on the environment and pave the way for the transition to a sustainable agriculture system.展开更多
The precise detection of lysozyme plays a crucial role in early diagnosis of kidney failure in leukemia patients.Herein,we designed an electrochemical aptasensor to detect lysozyme using a glassy carbon electrode(GCE)...The precise detection of lysozyme plays a crucial role in early diagnosis of kidney failure in leukemia patients.Herein,we designed an electrochemical aptasensor to detect lysozyme using a glassy carbon electrode(GCE)modified with molybdenum disulfide(MoS_(2))nanosheets decorated with chitosan(Ch)and gold nanoparticles(Au).In the next steps of aptasensor preparation,aptamer(Apt)strands were immobilized on MoS_(2)-Au-Ch/GCE surface via electrostatic interactions,and bovine serum albumin(BSA)solution was applied to cover unbonded areas on Apt/MoS_(2)-Au-Ch/GCE.The MoS_(2)-Au-Ch nanocomposite can warrant enhanced immobilization of aptamers and strong signals because of wrinkle-like structure and base planes in MoS nanosheets,presence of abundant amino and carboxyl functional groups in chitosan and Au nanoparticles.Differential pulse voltammetry(DPV)was used to evaluate the electrochemical behavior of the aptasensor at each preparation step and its detection performance.The developed electrochemical aptasensor based on MoS nanosheets showed remarkable performance for lysozyme detection in the range from 1 pmol/L to 10 nmol/L with a limit of detection of 2.2 fmol/L.The proposed aptasensor provided excellent selectivity against BSA,uric acid,cytochrome C,lysozyme and their mixture.In addition,it displayed great stability of about 99.58%of the initial signal upon 21-day storage.Tests on human serum and urine samples yielded promising recoveries ranging from 98 to 105%.Hence,MoS_(2)-Au-Ch nanocomposite-based aptasensor could be an outstanding candidate for medical device applications and protein quantification.展开更多
文摘Toxicity is the totality of adverse effects, which can be functional and morphological lesions in a living organism, caused by a substance introduced in relatively high single doses or in small, repeated doses. The aim of this study was to assess the OECD-recommended acute oral toxicity and anti-inflammatory activity of ethanolic extract of Ficus umbellata leaves. Animals were given a single oral dose of 1000, 3000 and 5000 mg/Kg body weight (BW) of the extract. For the anti-inflammatory activity test, rats were given the ethanolic extract of F. umbellata leaves at doses of 100, 300 and 500 mg/Kg or aspirin® at a concentration of 100 mg/Kg PC orally, one hour before injection of 0.05 ml of 1% formalin under the plantar fascia of the rat’s right hind paw. Paw volume measurements were taken one, two and three hours after formalin injection, using an electronic caliper. After 14 days of observation, no deaths were observed in treated rats. The LD50 of ethanolic extract of Ficus umbellata leaf powder is greater than 5000 mg/Kg body weight. This extract has no significant effects on hematological parameters and on the main markers of nephrotoxicity and hepatotoxicity for a single dose of less than 5000 mg/Kg PC. It reduces formalin-induced edema. Evaluation of the percentage inhibition showed that the extract had greater anti-inflammatory activity at 3 hours after the start of the experiment. However, better inhibition of inflammatory oedema of the paw of rats treated with 500 mg/Kg was observed at 5 hours after the start of the experiment, with a percentage inhibition of 69.23 ± 1.02, compared with the reference group treated with aspirin® 100 mg/Kg, which showed an inhibition of 63.50 ± 0.98. These results show that F. umbellata leaves possess anti-inflammatory activity, which would justify their use in traditional African medicine to prevent or treat inflammation.
文摘Haptoglobin(HP)is a liver glycoprotein that is actively synthesized during in-flammatory and hemolytic processes.It also has pro-oxidant and proinflam-matory properties,which are a function of its genotype.The genetic polymorp-hism of the chains leads to synthesis of three phenotypes/proteins,which are related to the number and type of chains and their molecular weight,namely HP1-1,HP1-2 and HP2-2.Patients with HP2-2 have more vascular complications,while those with HP1-1 have fewer.HP is involved in the worsening of diseases,such as HP2-2 in aggravation of vaso-occlusive crises in sickle cell disease,and worsening of the pathophysiology of other diseases.In contrast,HP1-1 confers better protection against diseases.All of this suggests that further studies should be conducted,including experimental and analytical studies focused on de-monstrating the influence of different HP genotypes on individual clinical and hematological data.This would help in understanding the role played by this genetic polymorphism in the pathophysiology of diseases.
文摘Introduction: Moringa oleifera was a medicinal plant generally used by populations in the food and therapeutic fields. It’s used to treat anemia has been observed in the Djougou Zone in northern Benin. To our knowledge, there were no scientific data available that have evaluated its efficacy in the treatment of haemolytic anemia. This was what justifies this research work in which the phytochemical analysis, extraction and evaluation of the anti-anemic effect were carried out. Methods: Five groups of five Wistar rats each were formed. All the rats were rendered anemic by injection of phenylhydrazine hydrochloride on the first two days D0 and D1 except those in the negative control group. From the second day, the anemic groups were force-fed either with the aqueous extract of Moringa oleifera leaves at 200 or 300 mg/kg body weight/day, or with vitafer, the reference drug against anemia. The positive control group (anemia) was not treated. Blood samples were taken from all the rats on different days: D0, D2, D7, D10 and D15 to evaluate the data of the hemogram and the osmotic resistance of the red blood cells. Results: Phytochemical analysis revealed the presence of tannins, flavonoids, leucoanthocyanins, saponosides, triterpenes and mucilages. A good yield was obtained at the extraction. Both the extract and the reference drug vitafer completely corrected anemia within two weeks after stimulating hemoglobin synthesis and early release of immature red blood cells into the bloodstream. Its effect seemed dose-dependent and specific. Conclusion: Moringa oleifera leaves showed good therapeutic efficacy and can be considered and exploited for transformation into improved traditional medicines (ITM) in the treatment of anemia.
基金Supported by Universiti Sains Malaysia Scientific Research Fund
文摘AIM: To investigate the impact of agitation speed on pectinase production and morphological changing of Aspergillus niger(A. niger) HFD5A-1 in submerged fermentation. METHODS: A. niger HFM5A-1 was isolated from a rotted pomelo. The inoculum preparation was performed by adding 5.0 m L of sterile distilled water containing 0.1% Tween 80 to a sporulated culture. Cultivation was carried out with inoculated 1 × 107 spores/m L suspension and incubated at 30 ℃ with different agitation speed for 6 d. The samples were withdrawn after 6 d cultivation time and were assayed for pectinase activity and fungal growth determination. The culture broth was filtered through filter paper(Whatman No. 1, London) to separate the fungal mycelium. The cell-free culture filtrate containing the crude enzyme was then assayed for pectinase activity. The biomass was dried at 80 ℃ until constant weight. The fungal cell dry weight was then expressed as g/L. The 6 d old fungal mycelia were harvested from various agitation speed, 0, 50, 100, 150, 200 and 250 rpm. The morphological changing of samples was then viewed under the light microscope and scanning electron microscope.RESULTS: In the present study, agitation speed was found to influence pectinase production in a batch cultivation system. However, higher agitation speeds than the optimal speed(150 rpm) reduced pectinase production which due to shear forces and also collision among the suspended fungal cells in the cultivation medium. Enzyme activity increased with the increasing of agitation speed up to 150 rpm, where it achieved its maximal pectinase activity of 1.559 U/m L. There were significant different(Duncan, P < 0.05) of the pectinase production with the agitation speed at static, 50, 100, 200 and 250 rpm. At the static condition, a well growth mycelial mat was observed on the surface of the cultivation medium and sporulation occurred all over the fungal mycelial mat. However with the increased in agitation speed, the mycelial mat turned slowly to become a single circular pellet. Thus, it was found that agitation speed affected the morphological characteristics of the fungal hyphae/mycelia of A. niger HFD5A-1 by altering their external as well as internal cell structures.CONCLUSION: Exposure to higher shear stress with an increasing agitation speed could result in lower biomass yields as well as pectinase production by A. niger HFD5A-1.
文摘The objective of this study was designed to evaluate the effects of biostimulation and bioaugmentation amendment agents (NPK fertilizer, Tween 80 and mixed culture) on the bioremediation of tropical soil samples artificially contaminated with Weathered Bonny Light Crude Oil (WBLCO). Response Surface Methodology (RSM) with Box Behnken Design (BBD) was used with three levels and three factors of NPK fertilizer (2 - 6 g), Tween 80 (5 - 15 mg/l) and mixed culture (0.5 - 1.5 g/l) as independent variables and WBLCO removal as dependent variable (response) in a six weeks remediation period. The results showed that the rate of WBLCO removal generally increased with increase in the amount of NPK fertilizer, Tween 80 and mixed culture (biomass), respectively. A statistically significant (P < 0.0001) second-order quadratic regression model for WBLCO removal (using design-expert statistical program (v. 6.0.8)) with a coefficient of determination, R (=0.9996) was obtained. Numerical optimization technique based on desirability function was carried out to optimize the bioremediation process. The optimum values for biostimulation and bioaugmentation amendment agents to achieve a predicted maximum WBLCO removal of 84.88 percent were found to be: NPK fertilizer, 4.25 g;Tween 80, 10.22 mg/l and mixed culture, 0.46 g/l. At this optimum point, the observed WBLCO removal was found to be 83.79 percent. The statistical analyses and the closeness of the experimental results and model predictions show the reliability of the regression model and thus, biostimulation and bioaugmentation of indigenous microbial density and activity can reduce remediation period of petroleum hydrocarbon contaminated environment and subsequently the cost of remediation.
文摘The depletion of world petroleum reserves and the increased environmental concerns have stimulated the search for alternative sources for petroleum based fuel. The possibility of using vegetable oils as fuel has been recognized, however, due to its high viscosities and low volatilities makes it inefficient for most combustion engines and thus the need to get them chemically altered or transesterified to obtain fatty alkyl esters of the oil (biodiesel). In this study, binary and ternary blends of biodiesel were produced and the effect of temperature on their viscosity and density was investigated. Biodiesel was produced from soybean oil by transesterification of the oil with methanol using potassium hydroxide as a catalyst at a temperature of 60℃ in a batch reactor. Binary and ternary blends of the soy-biodiesel were prepared with soy bean oil and petroleum diesel fuel, respectively. Viscosities and densities of the binary and ternary blends were measured at different temperatures of 20℃ to 90℃ as to determine the effect of temperature on viscosities and densities of the blends. The properties of the soy-biodiesel produced were compared with ASTM standard and found to be within the limits. The results show that the viscosities and densities of both the binary and ternary blends are temperature dependent. The viscosities of binary and ternary blends decreased nonlinearly with temperature, while their densities decreased linearly with temperature. The variation of temperature with viscosity and density of the blends was correlated and the polynomial equation offered the best correlation between temperature and viscosity, while linear equation gave the best correlation between temperature and density. In conclusion, the efficiency of binary and ternary blends of biodiesel in combustion engines is dependent on the viscosity and density of the blends which are invariably temperature dependent.
文摘Hepatitis C virus(HCV) is a major health problem worldwide. Early detection of the infection will help better management of the infected cases. The monoclonal antibodies(m Ab) of mice are predominantly used for the immunodiagnosis of several viral,bacterial,and parasitic antigens. Serological detection of HCV antigens and antibodies provide simple and rapid methods of detection but lack sensitivity specially in the window phase between the infection and antibody development. Human mA b are used in the immunotherapy of several blood malignancies,such as lymphoma and leukemia,as well as for autoimmune diseases. In this review article,we will discuss methods of mouse and human monoclonal antibody production. We will demonstrate the role of mouse mA b in the detection of HCV antigens as rapid and sensitive immunodiagnostic assays for the detection of HCV,which is a major health problem throughout the world,particularly in Egypt. We will discuss the value of HCV-neutralizing antibodies and their roles in the immunotherapy of HCV infections and in HCV vaccine development. We will also discuss the different mechanisms by which the virus escape the effect of neutralizing mA b. Finally,we will discuss available and new trends to produce antibodies,such as egg yolk-based antibodies(Ig Y),production in transgenic plants,and the synthetic antibody mimics approach.
基金The Ministry of Science, Technology and Innovation and Universiti Sains Malaysia for awarding the RUI research grant ( RUT1001 /pkimia/ 855006 ) to support this study
文摘Objective:To extract the bioactive compound from Enteromorpha intestinalis(E. intestinalis) and determine its in vitro antimicrobial activity. Methods: E. intestinalis was extracted by methanol and subjected to antimicrobial screening. The antimicrobial activity was studied by using disc diffusion and broth dilution method. The effect of the extract on the growth profile of the bacterial was also examined via time-kill assay. Microscopy observations using SEM was done to determine the major alterations in the microstructure of methicillin-resistant Staphylococcus aureus(MRSA). Results: The results showed methanolic extract of E. intestinalis exhibited a favourable antimicrobial activity against tested bacteria with produced inhibition zone ranging from 8.0-19.0 mm. However, all the tested fungi and yeast were resistant to the extract treatment. Time kill assay suggested that methanolic extract of E. intestinalis had completely inhibited MRSA growth and also exhibited prolonged antibacterial activity. The main abnormalities noted from the microscopic observations were the structural deterioration in the normal morphology and complete collapsed of the bacteria cells after 36 h of treatment. Conclusions: The significant antibacterial activity shown by crude extract suggested its potential against MRSA infection. The extract may have potential to develop as antibacterial agent in pharmaceutical use.
文摘OBJECTIVE To observe anti-tumor effects of PVAX-PSMA gene vaccine. METHODS The PSMA gene was inserted into a mammalian expression vector, PVAX-1, to construct the DNA vaccine candidate, and was then used to vaccinate C57BL/6 mice. Animals vaccinated with PVAX-1 and NaC1 were used as controls. Anti-PSMA antibody was detected in sera of the animals. The proliferation and cytotoxicity of the spleen cells were observed. The immunized mice were inoculated with RM-1 cells. The mice were inoculated with RM-1 cells, and then the mice were immunized. The anti-tumor efficacy of the gene vaccine was evaluated by the ratio of tumor formation, tumor volume, tumor mass before and after gene vaccination and evaluated by survival rate of the immunized mice. RESULTS High level of anti-PSMA antibody was induced in the PVAX-PSMA group. The splenocytes from PVAX-PSMA group were stimulated to produce strong proliferation responses and significant cytotoxic T-cells (CTL) activity. After the mice were immunized with PVAX-PSMA gene, tumor occurrence was decreased, and the growth velocity of tumor was markedly reduced, resulting in prolonged tumor-free time (P 〈 0.05). CONCLUSION PVAX-PSMA gene vaccine has significant anti- tumor effects and provides an experimental basis for primary prevention and immunotherapy of prostate cancer.
基金This study was supported by grants from the National Key Research and Development Plan(Nos.2016YFD0500204 and 2017YFD0500800)National Natural Science Foundation of China(Nos.31772753,31572543,31700136 and 31702237)+1 种基金Shanghai Municipal Natural Science Foundation(No.17ZR1437400)the Project of the Shanghai Science and Technology Commission(No.17391901700).
文摘The H9N2 subtype avian influenza virus(AIV)inactivated vaccine has been used extensively in poultry farms,but it often fails to stimulate a sufficiently high immune response in poultry in the field,although it works well in laboratory experiments;hence,the virus still causes economic damage every year and poses a potential threat to public health.Based on surveillance data collected in the field,we found that broilers with high levels of maternal-derived antibodies(MDAs)against H9N2 virus did not produce high levels of antibodies after vaccination with a commercial H9N2 inactivated vaccine.In contrast,specific pathogen-free(SPF)chickens without MDAs responded efficiently to that vaccination.When MDAs were mimicked by administering passively transferred antibodies(PTAs)into SPF chickens in the laboratory,similar results were observed:H9N2-specific PTAs inhibited humoral immunity against the H9N2 inactivated vaccine,suggesting that H9N2-specific MDAs might hinder the generation of antibodies when H9N2 inactivated vaccine was used.After challenge with homologous H9N2 virus,the virus was detected in oropharyngeal swabs of the vaccinated and unvaccinated chickens with PTAs but not in the vaccinated chickens without PTAs,indicating that H9N2-specific MDAs were indeed one of the reasons for H9N2 inactivated vaccine failure in the field.When different titers of PTAs were used to mimic MDAs in SPF chickens,high(HI=12 log2)and medium(HI=log 9 log2)titers of PTAs reduced the generation of H9N2-specific antibodies after the first vaccination,but a booster dose would induce a high and faster humoral immune response even of PTA interference.This study strongly suggested that high or medium titers of MDAs might explain H9N2 inactivated vaccine failure in the field.
文摘The use of natural hydrogels in agriculture provides solutions to many problems without threatening the environment. This study aims to evaluate the potential impact of environmentally friendly hydrogels (pectin, starch and pectin + starch) in reducing the negative effects of drought stress on tomato yield and quality. Two different peels (orange peel and banana peel) are used to prepare environmentally friendly hydrogels. The water retention efficiency of hydrogels has been studied. Greenhouse experiment for tomato under drought stress was conducted during 2019. These hydrogels were used under several level of irrigation (100%, 75%, and 50% FC), soil without hydrogel was used as a control. The results showed that the eco-friendly hydrogels (starch, pectin, and pectin + starch) had capacity retention of water for a long time. The obtained data from the greenhouse experiment showed that the eco-friendly hydrogel showed a positive effect on retention of water and increase the soil moisture content compared to control. The highest increase was observed at pectin + starch treatment. This increase reached to 2.8-, 2.4- and 2.0-fold for 100%, 75% and 50% FC compared to the control. Eco-</span></span></span></span><span><span><span><span><span style="font-family:""> </span></span></span></span></span><span><span><span><span><span style="font-family:"">friendly hydrogel application under different drought conditions led to improve yield and quality of tomato fruits. Moreover, conversion of agricultural wastes to hydrogels and the use of these eco-friendly materials instead of synthetic hydrogels are necessary to utilize the limited natural resources and decrease the harmful impact of agricultural wastes on the environment and pave the way for the transition to a sustainable agriculture system.
基金supported by Babol Noshirvani University of Technology[grant number BNUT/965115004/1402]Iran National Science Foundation(INSF)under grant number 98020065.
文摘The precise detection of lysozyme plays a crucial role in early diagnosis of kidney failure in leukemia patients.Herein,we designed an electrochemical aptasensor to detect lysozyme using a glassy carbon electrode(GCE)modified with molybdenum disulfide(MoS_(2))nanosheets decorated with chitosan(Ch)and gold nanoparticles(Au).In the next steps of aptasensor preparation,aptamer(Apt)strands were immobilized on MoS_(2)-Au-Ch/GCE surface via electrostatic interactions,and bovine serum albumin(BSA)solution was applied to cover unbonded areas on Apt/MoS_(2)-Au-Ch/GCE.The MoS_(2)-Au-Ch nanocomposite can warrant enhanced immobilization of aptamers and strong signals because of wrinkle-like structure and base planes in MoS nanosheets,presence of abundant amino and carboxyl functional groups in chitosan and Au nanoparticles.Differential pulse voltammetry(DPV)was used to evaluate the electrochemical behavior of the aptasensor at each preparation step and its detection performance.The developed electrochemical aptasensor based on MoS nanosheets showed remarkable performance for lysozyme detection in the range from 1 pmol/L to 10 nmol/L with a limit of detection of 2.2 fmol/L.The proposed aptasensor provided excellent selectivity against BSA,uric acid,cytochrome C,lysozyme and their mixture.In addition,it displayed great stability of about 99.58%of the initial signal upon 21-day storage.Tests on human serum and urine samples yielded promising recoveries ranging from 98 to 105%.Hence,MoS_(2)-Au-Ch nanocomposite-based aptasensor could be an outstanding candidate for medical device applications and protein quantification.