ABSTRACT
Background: Diabetes is one of the fastest-growing health emergencies of the 21st century, placing a severe economic burden on many countries. Current management approaches have improved diabetic care, but several limitations still exist, such as decreased efficacy, adverse effects, and the high cost of treatment, particularly for developing nations. There is, therefore, a need for more cost-effective therapies for diabetes management. The evidence-based application of phytochemicals from plants in the management of diseases is gaining traction. Methodology: Various plants and plant parts have been investigated as antidiabetic agents. This review sought to collate and discuss published data on the cellular and molecular effects of medicinal plants and phytochemicals on insulin signaling pathways to better understand the current trend in using plant products in the management of diabetes. Furthermore, we explored available information on medicinal plants that consistently produced hypoglycemic effects from isolated cells to animal studies and clinical trials. Results: There is substantial literature describing the effects of a range of plant extracts on insulin action and insulin signaling, revealing a depth in knowledge of molecular detail. Our exploration also reveals effective antidiabetic actions in animal studies, and clear translational potential evidenced by clinical trials. Conclusion: We suggest that this area of research should be further exploited in the search for novel therapeutics for diabetes.
Subject(s)
Diabetes Mellitus , Plants, Medicinal , Animals , Diabetes Mellitus/drug therapy , Hypoglycemic Agents/pharmacology , Insulin/therapeutic use , Phytotherapy , Plants, Medicinal/chemistry , HumansABSTRACT
This study investigated the protective effects of carvedilol alone and coadministered with prednisolone and diltiazem on doxorubicin (DOX) and 5-fluorouracil (5-FU)-induced toxicity. Each of 2 pools of 70 female rats were randomly allotted into 10 groups of 7 animals each and treated as follows: Group 1: normal saline (10 mL/kg); Group 2: normal saline and DOX (40 mg/kg)/5-FU (20 mg/kg) alone; Group 3: gallic acid (200 mg/kg) and DOX/5-FU; Group 4: carvedilol (0.075 mg/kg) and DOX/5-FU; Group 5: carvedilol (0.15 mg/kg) and DOX/5-FU; Group 6: carvedilol (0.30 mg/kg) and DOX/5-FU; Group 7: diltiazem (3.43 mg/kg) and DOX/5-FU; Group 8: diltiazem (3.43 mg/kg), carvedilol (0.15 mg/kg), and DOX/5-FU; Group 9: prednisolone (0.57 mg/kg) and DOX/5-FU; and Group 10: prednisolone (0.57 mg/kg), carvedilol (0.15 mg/kg), and DOX/5-FU. Treatments were done p.o. for 16/14 days for the DOX/5-FU models. DOX/5-FU was administered i.p. to the rats in Groups 2-10 on day 14/10-14. On day 17/15 (DOX/5-FU), blood samples were collected, and liver and kidneys of rats were harvested for antioxidant and histopathological assessments. Carvedilol alone and coadministered with prednisolone significantly (P < .05) decreased alanine aminotransferase level compared with administration of DOX alone. Carvedilol alone and coadministered with diltiazem significantly (P < .05) decreased creatinine level compared with administration of DOX/5-FU alone. Carvedilol alone and coadministered with diltiazem and prednisolone significantly (P < .05) increased the level of hepatic superoxide dismutase and catalase, and decreased malondialdehyde compared with DOX administration alone. Histopathological observations correlated with results of biochemical and antioxidant analyses. Carvedilol administered alone and coadministered with diltiazem and prednisolone reduced the effect of DOX/5-FU-induced hepatic and renal toxicities due to enhanced in vivo antioxidant activity. The protective effect was more prominent in the doxorubicin model compared with the 5-fluorouracil test. Coadministration of carvedilol with either diltiazem or prednisolone did not show better protection relative to carvedilol alone.
Subject(s)
Acute Kidney Injury/prevention & control , Antibiotics, Antineoplastic/toxicity , Chemical and Drug Induced Liver Injury/prevention & control , Protective Agents/pharmacology , Acute Kidney Injury/chemically induced , Acute Kidney Injury/pathology , Animals , Carbazoles/pharmacology , Carbazoles/therapeutic use , Carvedilol , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/pathology , Diltiazem/pharmacology , Diltiazem/therapeutic use , Disease Models, Animal , Doxorubicin/toxicity , Drug Therapy, Combination/methods , Female , Fluorouracil/toxicity , Humans , Kidney/drug effects , Kidney/pathology , Lipid Peroxidation/drug effects , Liver/drug effects , Liver/pathology , Oxidative Stress/drug effects , Prednisolone/pharmacology , Prednisolone/therapeutic use , Propanolamines/pharmacology , Propanolamines/therapeutic use , Protective Agents/therapeutic use , Random Allocation , Rats , Rats, Wistar , Treatment OutcomeABSTRACT
Tuberculosis therapy utilizes drugs that while effective cause treatment-related toxicity. Modulation of antitubercular drugs-induced toxicity by methionine and vitamin B-complex in patients was evaluated. 285 treatment-naïve tuberculosis patients at the Chest Clinics of Infectious Diseases Hospital, Yaba and General Hospital, Lagos in Lagos, Nigeria was prospectively recruited and allotted into test (antitubercular medicines, methionine and vitamin B-complex) and control groups (antitubercular medicines). Data on adverse drug reactions and blood samples were collected at initiation, 2 months and 6 months, and then analyzed. Red blood cells and packed cell volume were significantly higher (P < 0.05) in the test group compared to control at 6 months of therapy. At the end of 2 months, results showed a significant decrease (P < 0.001) in aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase, urea, creatinine and total bilirubin in the test group compared to control. Reduced glutathione and superoxide dismutase were significantly increased (P < 0.001) and malondialdehyde significantly decreased (P < 0.001) in the test versus control groups at the end of 2 and 6 months. Adverse drug reactions were significantly lower (P < 0.001) in the test group (32.4%) compared to control group (56.2%), with 1 death. Hepatotoxicity was significantly higher (P = 0.026) in control (6.9%), compared to test group (0%). Alcohol and cigarette smoking were significantly (P = 0.019 and P = 0.027) associated with the occurrence of adverse drug reactions. Methionine and vitamin B-complex modulated hepatic, renal, hematological, antioxidant indices and adverse effects in patients administered antitubercular medicines. Such interventions can enhance compliance and better treatment outcomes in tuberculosis patients.
Subject(s)
Antitubercular Agents/adverse effects , Drug-Related Side Effects and Adverse Reactions/drug therapy , Methionine/administration & dosage , Tuberculosis/drug therapy , Vitamin B Complex/administration & dosage , Adult , Alanine Transaminase/blood , Alkaline Phosphatase/blood , Antitubercular Agents/pharmacology , Aspartate Aminotransferases/blood , Drug Therapy, Combination , Drug-Related Side Effects and Adverse Reactions/blood , Drug-Related Side Effects and Adverse Reactions/metabolism , Female , Humans , Male , Methionine/pharmacology , Middle Aged , Nigeria , Prospective Studies , Tuberculosis/blood , Tuberculosis/metabolism , Vitamin B Complex/pharmacology , Young AdultABSTRACT
BACKGROUND: The UK military runs a comprehensive mental health service ordinarily accessed via primary care referrals. AIMS: To evaluate the feasibility of self-referral to mental health services within a military environment. METHODS: Three pilot sites were identified; one from each service (Royal Navy, Army, Air Force). Socio-demographic information included age, rank, service and career duration. Clinical data included prior contact with general practitioner (GP), provisional diagnosis and assessment outcome. RESULTS: Of the 57 self-referrals, 69% (n = 39) had not previously accessed primary care for their current difficulties. After their mental health assessment, 47 (82%) were found to have a formal mental health problem and 41 (72%) were offered a further mental health clinician appointment. The data compared favourably with a large military mental health department that reported 87% of primary care referrals had a formal mental health condition. CONCLUSIONS: The majority of self-referrals had formal mental health conditions for which they had not previously sought help from primary care; most were offered further clinical input. This supports the view that self-referral may be a useful option to encourage military personnel to seek professional care over and above the usual route of accessing care through their GP.
Subject(s)
Mental Health Services/statistics & numerical data , Military Personnel/psychology , Self Report , Adolescent , Adult , Female , Humans , Male , Mental Disorders/diagnosis , Military Personnel/statistics & numerical data , Pilot Projects , United KingdomABSTRACT
AIMS: Reduced aspirin efficacy has been demonstrated in people with Type 2 diabetes. Because increased platelet reactivity and/or turnover are postulated mechanisms, we examined whether higher and/or more frequent aspirin dosing might reduce platelet reactivity more effectively. METHODS: Participants with Type 2 diabetes (n = 24) but without known cardiovascular disease were randomized in a three-way crossover design to 2-week treatment periods with aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily. The primary outcome was platelet reactivity, assessed using the VerifyNow(™) ASA method. Relationships between platelet reactivity and aspirin dosing were examined using generalized linear mixed models with random subject effects. RESULTS: Platelet reactivity decreased from baseline with all doses of aspirin. Modelled platelet reactivity was more effectively reduced with aspirin 100 mg twice daily vs. 100 mg once daily, but not vs. 200 mg once daily. Aspirin 200 mg once daily did not differ from 100 mg once daily. Aspirin 100 mg twice daily was also more effective than once daily as measured by collagen/epinephrine-stimulated platelet aggregation and urinary thromboxane levels, with a similar trend measured by serum thromboxane levels. No episodes of bleeding occurred. CONCLUSIONS: In Type 2 diabetes, aspirin 100 mg twice daily reduced platelet reactivity more effectively than 100 mg once daily, and numerically more than 200 mg once daily. Clinical outcome trials evaluating primary cardiovascular disease prevention with aspirin in Type 2 diabetes may need to consider using a more frequent dosing schedule.
Subject(s)
Aspirin/administration & dosage , Cardiovascular Diseases/prevention & control , Cyclooxygenase Inhibitors/administration & dosage , Diabetes Mellitus, Type 2/complications , Diabetic Angiopathies/prevention & control , Diabetic Cardiomyopathies/prevention & control , Platelet Aggregation Inhibitors/administration & dosage , Adult , Aspirin/adverse effects , Aspirin/therapeutic use , Cardiovascular Diseases/complications , Cardiovascular Diseases/epidemiology , Cross-Over Studies , Cyclooxygenase Inhibitors/adverse effects , Cyclooxygenase Inhibitors/therapeutic use , Diabetes Mellitus, Type 2/blood , Diabetic Angiopathies/epidemiology , Diabetic Cardiomyopathies/epidemiology , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Drug Resistance , England/epidemiology , Female , Hemorrhage/chemically induced , Hemorrhage/complications , Hemorrhage/epidemiology , Humans , Male , Middle Aged , Platelet Activation/drug effects , Platelet Aggregation Inhibitors/adverse effects , Platelet Aggregation Inhibitors/therapeutic use , Risk , Risk AssessmentABSTRACT
BACKGROUND: National Agency for Food and Drugs Administration and Control (NAFDAC), which is responsible for pharmacovigilance activity in Nigeria, recently withdrew injection gentamicin 280 mg, used in the management of life-threatening and multidrug-resistant infections from circulation, due to reported toxicity. Thus, this study aimed to investigate the toxicity profile of the commonly used strengths (80 mg and 280 mg) of gentamicin on kidney using animal models. METHODS: Animals were divided into five groups of 16 rats each. For rats of groups 1 and 2, gentamicin (1.14 mg/kg each group) was administered intramuscularly twice daily for 7 and 14 days, respectively, after which eight of them were sacrificed by cervical dislocation. Blood was collected via cardiac puncture and the kidneys were carefully removed and weighed immediately. The remaining eight animals were kept for reversibility study for another 7 and 14 days, respectively. For groups 3 and 4, gentamicin (4 mg/kg each group) was administered as a single daily dose for 7 and 14 days, respectively, and eight animals from the groups were subjected to reversibility study for 7 and 14 days, respectively. Group 5, the control group animals, were given 10 ml/kg distilled water for 14 days. Histopathology of the kidneys, serum creatinine levels, and antioxidant enzyme activities were investigated. RESULTS: Significant increase (p ≤ 0.001) in the level of creatinine of rats administered 4.0 mg/kg for 14 days was observed compared with all other groups. Significant (p ≤ 0.001) elevations in the lipid peroxidation in all gentamicin-administered animals and acute tubular necrosis in most of the gentamicin-administered animals were observed. CONCLUSION: Toxicity profile of gentamicin on the kidneys is dependent on both dose and duration of administration. The findings justify the decision made by NAFDAC to ban the use of high-dose inj. gentamicin 280 mg in Nigeria.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/therapeutic use , Gentamicins/pharmacology , Kidney/drug effects , Pharmacovigilance , Animals , Creatinine/metabolism , Lipid Peroxidation/drug effects , Lipid Peroxidation/physiology , RatsABSTRACT
OBJECTIVES: The aim of the study was to examine whether UK HIV testing guidelines which recommend the expansion of HIV testing in high HIV prevalence areas have been implemented in England. METHODS: An online survey tool was used to conduct an audit of sexual health commissioners in 40 high HIV prevalence areas (diagnosed prevalence > 2 per 1000) between May and June 2012. Responders were asked to provide details of expanded HIV testing programmes that they had commissioned in nontraditional settings and perceived barriers and facilitators involved in introducing expanded testing. RESULTS: The response rate was 88% (35 of 40). Against the key audit standards, 31% (11 of 35) of areas had commissioned routine testing of new registrants in general practice, and 14% (five of 35) routine testing of general medical admissions. The majority of responders (80%; 28 of 35) had commissioned some form of expanded testing, often targeted at risk groups. The most common setting for commissioning of testing was the community (51%; 18 of 35), followed by general practice (49%; 17 of 35) and hospital departments (36%; 13 of 35). A minority (11%; four of 35) of responders had commissioned testing in all three settings. Where testing in general practice took place this was typically in a minority of practices (median 10-20%). Most (77%; 27 of 35) expected the rate of HIV testing to increase over the next year, but lack of resources was cited as a barrier to testing by 94% (33 of 35) of responders. CONCLUSIONS: Not all high HIV prevalence areas in England have fully implemented testing guidelines. Scale-up of existing programmes and continued expansion of testing into new settings will be necessary to achieve this.
Subject(s)
HIV Infections/epidemiology , Mass Screening , Clinical Audit , Data Collection , England/epidemiology , Humans , Practice Guidelines as TopicABSTRACT
BACKGROUND: Despite the reported widespread use of herbal medicines globally and their benefits, they are not completely without potential to cause harm. The haphazard, irresponsible or non-regulated use of several herbal medicines may put the health of their users at risk of toxicity. OBJECTIVE: This study aimed to assess the general perception of the safety and occurrence of adverse effects of herbal medicines among residents of Ikorodu in Lagos, Nigeria. METHODS: The study population included 400 randomly selected and consented residents in Ikorodu. Data was collected using a standard closed and open-ended structured questionnaire with three (3) sections on socio-demography, safety and adverse effects of herbal medicines. Associations between the variables were determined using Chi square analysis. RESULTS: The results showed that 333 respondents (82.4%) believed that herbal medicines are safe for use and only 39 (9.7%) held the view that they may not be safe. RESULTS also show that 51 (12.6%) of respondents had experienced adverse effects while 250 (61.9%) said they had never experienced adverse effects from the use of herbal medicines. CONCLUSION: Herbal medicine is popular among the respondents but they appear to be ignorant of its potential toxicities. It may be necessary to educate the consumers of herbal medicines on the potentials for herbs-drugs interaction and adverse effects specially as a result of indiscriminate and unguided use of herbal medicines.
Subject(s)
Herbal Medicine , Phytotherapy/adverse effects , Adult , Female , Humans , Male , Middle Aged , NigeriaABSTRACT
BACKGROUND: The requirements and methods for research and evaluation of the safety and efficacy of herbal medicines are more complex than those for conventional pharmaceuticals. In addition to the aforementioned and contrary to the general belief that herbal medicines are safe and despite the profound therapeutic advantages possessed by medicinal plants, some of their constituents have been shown to be potentially toxic, carcinogenic, mutagenic, and teratogenic. Thus, traditional medicine policy and regulation have been made an integral part of the WHO proposed critical determinants of herbal medicine safety. OBJECTIVE: Therefore, this study is designed to assess the policy and regulation guiding herbal medicine in Nigeria as this information may form a safety index of herbal medicine use in Nigeria. METHODOLOGY: Structured questionnaire adopted from WHO was used to obtain the opinions of relevant stakeholders in the field of herbal medicine on the policy and regulation of herbal medicine in Nigeria. RESULTS: The results show that 68.8% of respondents agreed that there is a national policy on TM with 31.2% disagreeing on this issue. 75% of respondents agreed that implementation of the manufacturing requirements of herbal medicines is ensured by control mechanisms while 25% disagreed. Only 25% said herbal medicines are sold by licensed practitioners, with 75% believing that herbal medicines are sold by non-licensed practitioners. 87.5% said support from the WHO is needed and should be in the form of workshops on national capacity building on safety monitoring of herbal medicines. CONCLUSION: There is need for the Federal Ministry of Health to harmonize the varying opinions on traditional medicine and policy as documented in this study through collaboration and workshops on traditional medicine. These proposed approaches may guarantee the safety and regulation of herbal medicine use in Nigeria.
Subject(s)
Health Policy/trends , Legislation, Medical/trends , Medicine, African Traditional/trends , Algorithms , Attitude of Health Personnel , Drug Prescriptions , Health Knowledge, Attitudes, Practice , Humans , Nigeria , Phytotherapy , Plant Preparations/adverse effects , Plant Preparations/therapeutic use , Plants, Medicinal , Surveys and Questionnaires , World Health OrganizationSubject(s)
Amyloid Neuropathies, Familial/diagnosis , Amyloid/chemistry , Mutation, Missense , Point Mutation , Prealbumin/analysis , Vision Disorders/diagnosis , Vitreous Body/chemistry , Amino Acid Substitution , Amyloid Neuropathies, Familial/complications , Amyloid Neuropathies, Familial/genetics , Amyloid Neuropathies, Familial/surgery , Humans , Male , Middle Aged , Phenotype , Prealbumin/genetics , Sequence Analysis, DNA , Vision Disorders/etiology , Vision Disorders/surgery , Visual Acuity , Vitrectomy , Vitreous Body/surgeryABSTRACT
A metal shell was used in this study to provide significant enhancement of the up-converted emission from cubic NaYF(4) nanoparticles, creating a valuable composite material for labeling in biology and other applications - use of the cubic form of the material obviates the need to undertake a high temperature transformation to the naturally more efficient hexagonal phase. The NaYF(4) matrix contained ytterbium sensitizer and an Erbium (Er) or Thulium (Tm) activator. The particle sizes of the as-synthesized nanoparticles were in the range of 20-40 nm with a gold shell thickness of 4-8 nm. The gold shell was macroscopically amorphous. The synthesis method was based on a citrate chelation. In this approach, we exploited the ability of the citrate ion to act as a reductant and stabilizer. Confining the citrate ion reductant on the nanophosphor surface rather than in the solution was critical to the gold shell formation. The plasmonic shell enhanced the up-conversion emission of Tm from visible and near-infrared regions by up to a factor of 8, in addition to imparting a visible color arising from the plasmon absorption of the gold shell. The up-conversion enhancement observed with Tm and Er were different for similar gold coverages, with local crystal field changes as a possible route to enhance up-conversion emission from high symmetry structural hosts. These novel up-converting nanophosphor particles combine the phosphor and features of a gold shell, providing a unique platform for many biological imaging and labeling applications.
ABSTRACT
Aspergillus flavus and Aspergillus parasiticus cause perennial infection of agriculturally important crops in tropical and subtropical areas. Invasion of crops by these fungi may result in contamination of food and feed by potent carcinogenic aflatoxins. Consumption of aflatoxin contaminated foods is a recognised risk factor for human hepatocellular carcinoma (HCC) and may contribute to the high incidence of HCC in Southeast Asia. This study conducted a survey of Vietnamese crops (peanuts and corn) and soil for the presence of aflatoxigenic fungi and used microsatellite markers to investigate the genetic diversity of Vietnamese Aspergillus strains. From a total of 85 samples comprising peanut (25), corn (45) and soil (15), 106 strains were isolated. Identification of strains by colony morphology and aflatoxin production found all Vietnamese strains to be A. flavus with no A. parasiticus isolated. A. flavus was present in 36.0% of peanut samples, 31.1% of corn samples, 27.3% of farmed soil samples and was not found in virgin soil samples. Twenty-five per cent of the strains produced aflatoxins. Microsatellite analysis revealed a high level of genetic diversity in the Vietnamese A. flavus population. Clustering, based on microsatellite genotype, was unrelated to aflatoxin production, geographic origin or substrate origin.
Subject(s)
Arachis/microbiology , Aspergillus flavus/isolation & purification , Aspergillus flavus/metabolism , Aspergillus/metabolism , Crops, Agricultural/microbiology , Zea mays/microbiology , Aflatoxins/biosynthesis , Aspergillus/classification , Aspergillus/genetics , Aspergillus/isolation & purification , Aspergillus flavus/classification , Aspergillus flavus/genetics , Genetic Variation , Geography , Microsatellite Repeats , Phylogeny , Soil Microbiology , VietnamABSTRACT
Vietnamese coffee beans were investigated for the presence of ochratoxigenic Aspergilli. Ninety-three percent of the coffee samples studied were positive for A. niger. No other ochratoxigenic species were present. HPLC analysis determined that 8.7% of the A. niger strains were positive for ochratoxin A (OA) production. There was no significant difference in the level of contamination or incidence of toxigenic strains in samples that had been rejected by manual sorting and those that were destined for human consumption. No OA-producing fungi were uncovered in a fresh coffee bean sample analysed, suggesting that the OA problem most likely occurs post-harvest.
Subject(s)
Aspergillus/isolation & purification , Aspergillus/metabolism , Coffea/microbiology , Food Microbiology , Ochratoxins/analysis , Seeds/microbiology , Aspergillus/chemistry , VietnamABSTRACT
The application of quantum dots (QDs) as labels in immunoassay microarrays for the multiplex detection of 3-phenoxybenzoic acid (PBA) and atrazine-mercapturate (AM) has been demonstrated. PBA and AM are biomarkers of exposure to the pyrethroid insecticides and to the herbicide atrazine, respectively. Microarrays were fabricated by microcontact printing of the coating antigens in line patterns onto glass substrates. Competitive immunoassays were successfully performed using QDs (QD560 and QD620) as reporters. The multiplexed immunoassays were characterized by fluorescence microscopy and SEM. The application of QD fluorophores facilitates multiplex assays and therefore can contribute to enhanced throughput in biomonitoring.
ABSTRACT
Aim of this study to review information on various aspects of P fertilization in rice i.e., P nutrition of rice, P response of rice plant, P availability in rice soils and P adsorption in rice soils for better understanding of P fertilization in rice culture. A substantial portion of the applied P along with the soil P is lost from rice fields to water bodies causing environmental pollution problems through eutrophication. These pollution problems can be minimized by using proper source of P as fertilizer, proper timing and methods of P fertilizer application, soil P management, transport management, use of plant growth promoting microorganisms which helps in efficient use of P by crops and use of green manure crops which improves soil fertility as well as helps in efficient use of P by crops.
Subject(s)
Crops, Agricultural/growth & development , Environmental Pollutants , Fertilizers , Oryza/growth & development , Phosphorus , Crops, Agricultural/metabolism , Oryza/metabolism , Phosphorus/metabolismABSTRACT
The oxidation state of iron oxide nanoparticles co-generated with soot during a combustion process was studied using electron energy-loss spectroscopy (EELS). Spatially resolved EELS spectra in the scanning transmission electron microscopy mode were collected to detect changes in the oxidation state between the cores and surfaces of the particles. Quantification of the intensity ratio of the white lines of the iron L-ionization edge was used to measure the iron oxidation state. Quantitative results obtained from Pearson's method, which can be directly compared with the literature data, indicated that the L3 /L2-intensity ratio for these particles changes from 5.5 +/- 0.3 in the particles' cores to 4.4 +/- 0.3 at their surfaces. This change can be directly related to the reduction of the iron oxidation state at the surface of the particles. Experimental results indicate that the cores of the particles are composed of gamma-Fe2O3, which seems to be reduced to FeO at their surfaces. These results were also supported by the fine structure of the oxygen K-edge and by the significant chemical shift of the iron L-edge.
ABSTRACT
A bacterium capable of metabolizing endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepine3-oxide) was isolated from cotton-growing soil and effectively shown to degrade endosulfan into endosulfan sulfate. The bacterium degraded 50% of the compound within 3 days of incubation. Endosulfan sulfate was the only terminal product and no other metabolites were formed during the incubation. Endosulfan and its metabolites were analyzed by gas chromatography. The metabolites formed indicated that the organism follows an oxidative pathway for metabolism of this pesticide. Therefore, the present study, microbial degradation of endosulfan by a soil bacterium, may provide a basis for the development of bioremediation strategies to remediate the pollutants in the environment.
Subject(s)
Bacillus/metabolism , Biodegradation, Environmental , Endosulfan/metabolism , Insecticides/metabolism , Soil Microbiology , Bacillus/classification , Bacillus/isolation & purification , Chromatography, Gas/methods , Time FactorsABSTRACT
The methods of analysis for sulphonamide residues in edible animal products are reviewed. Sulphonamides are widely used for therapeutic and prophylactic purposes in both humans and animals, sometimes as growth promoters as additives in animal feed. As a result of their widespread use, there is concern about whether the levels used of these drugs can generate serious problems in human health, e.g., allergic or toxic reactions. Several methods for the determination of sulphonamides have been reported in the literature and this review considers high-performance liquid chromatography (HPLC), liquid chromatography-mass spectrometry (LC/MS), gas chromatography (GC), thin-layer chromatography (TLC), high-performance capillary electrophoresis (HPCE), enzyme-linked immunosorbant assay (ELISA), biosensor immunoassay (BIA) and microbiological methods. Specific aspects of analysing sulphonamides, such as sample handling, chromatographic conditions and detection methods are discussed. Methods for drug residue monitoring should be accurate, simple, economical in both time and cost, and capable of detecting residues below the maximum residue limits (MRL). The current sulphonamide detection technologies are based on chromatographic methods or bacteriological growth inhibition. The instrumental methods such as HPLC and GC are both sensitive and specific, but are laborious and expensive. Because of the labour-intensive processes, only a few cases of GC methods applied to residue analysis have been published. These methods are suitable for confirmation but not for screening of large numbers of samples. Microbiological methods do not require highly specialized and expensive equipment. They also use highly homogeneous cell populations for testing and thus result in better assay precision. Although HPCE has powerful separation ability, the precision is poor and the instrument still needs to be improved. To date, this technique has not been widely applied to routine analysis. Currently, TLC has been almost replaced by other instrumental analysis. A rapid, sensitive and specific assay is required to detect positive samples in routine analysis, which can then be confirmed for the presence of sulphonamides by HPLC. Immunochemical methods such as ELISA can be simple, rapid and cost-effective, with enough sensitivity and specificity to detect small molecules. This review can be considered as a basis for further research aimed at identifying the most efficient approaches.
Subject(s)
Drug Residues/analysis , Food Analysis/methods , Food Contamination/analysis , Sulfonamides/analysis , Animals , Anti-Infective Agents/analysis , Biosensing Techniques/methods , Chromatography, Gas/methods , Chromatography, High Pressure Liquid/methods , Chromatography, Thin Layer/methods , Drug Residues/chemistry , Electrophoresis, Capillary/methods , Enzyme-Linked Immunosorbent Assay/methods , Humans , Microbiological Techniques/methods , Sulfonamides/chemistryABSTRACT
We have demonstrated the use of an optical indium tin oxide (ITO) (quartz) waveguide as a new platform for immunosensors with fluorescent europium(III) chelate nanoparticle labels (Seradyn) in a competitive atrazine immunoassay. ITO as a solid surface facilitated the successful use of particulate labels in a competitive assay format. The limit of detection in the new nanoparticle assay was similar to a conventional ELISA. The effect of particle size on bioconjugate binding kinetics was studied using three sizes of bioconjugated particle labels (107, 304, and 396nm) and a rabbit IgG/anti-IgG system in a 96-well plate. A decrease in particle size resulted in faster binding but did not increase the assay sensitivity. Flux calculations based on the particle diffusivity prove that faster binding of the small particles in this study was primarily due to diffusion kinetics and not necessarily to a higher density of antibodies on the particle surface. The results suggest that ITO could make a good platform for an optical immunosensor using fluorescent nanoparticle labels in a competitive assay format for small molecule detection. However, when used in combination with fluorescent particulate labels, a highly sensitive excitation/detection system needs to be developed to fully utilize the kinetic advantage from small particle size. Different regeneration methods tested in this study showed that repeated washings with 0.1 M glycine-HCl facilitated the reuse of the ITO waveguide.
Subject(s)
Atrazine/analysis , Biosensing Techniques/methods , Europium/chemistry , Fluoroimmunoassay/methods , Herbicides/analysis , Nanotubes/chemistry , Tin Compounds/chemistry , Atrazine/chemistry , Biosensing Techniques/instrumentation , Chelating Agents/chemistry , Coated Materials, Biocompatible/chemistry , Fluorescent Dyes/chemistry , Fluoroimmunoassay/instrumentation , Herbicides/chemistry , Particle SizeABSTRACT
Although the use of endosulfan to control cotton pests has declined, this insecticide still has widespread application in agriculture and can contaminate riverine systems as runoff from soil or by aerial deposition. The degradation of endosulfan in pure water at different pH values of 5, 7 and 9 and in river water from the Namoi and the Hawkesbury rivers of New South Wales (NSW), Australia, was studied in the laboratory. Endosulfan transformation into endosulfan sulfate in river water using artificial mesocosms was also investigated. The results show endosulfan is stable at pH 5, with increasing rates of disappearance at pH 7 and pH 9 by chemical hydrolysis. Incubation of endosulfan with river water at pH 8.3 resulted in the disappearance of endosulfan and the formation of endosulfan diol due to the alkaline pH as well as formation of endosulfan sulfate. Although the degradation of endosulfan by Anabaena, a blue-green alga, did not result in the transformation of endosulfan to endosulfan sulfate, we conclude that other microorganisms catalyzed the formation of the sulfate. Significant conversions of endosulfan into endosulfan sulfate were also reported from associated field studies using artificial mesocoms containing irrigation water from rivers inhabitated by micro-macro fauna. From these results, we conclude that the presence of endosulfan sulfate in river water cannot be used to distinguish contamination by runoff from soil from contamination by aerial drift or redeposition.