ABSTRACT
The Astragalus grahamianus (AG) Royle ex. Benth is traditionally used for the treatment of various human disorders. The current research work is aimed to explore the neuroprotective anti-Parkinson effects of various fractions of Astragalus grahamianus (A. grahamianus). Fine powder of Astragalus grahamianus was extracted with 70% methanol and then fractionated with various solvents on the basis of polarity. Standard protocols were used to investigate the bioactive constituents present in the various plant fractions. In-vitro antioxidant potential of various fractions was checked using diverse free radicals. In-vivo rats model was used to determined the neuroprotective effects of methanol fraction of A. grahamianus. The results revealed that various fractions of A. grahamianus contain flavonoids, cardiac glycosides, steroids, gums, terpenes, proteins, and carbohydrates except chloroform fraction lake the presence of steroids, cardiac glycosides, gums and saponins, aqueous fraction of steroids, terpenoids, gums and saponins, n-Hexane fraction steroids, carbohydrates, alkaloids, gums and flavonoids. The highest amount of total phenolic contents was found in AGME (32.67 ± 2.3 mg GAE / g). The AGME also showed enhanced free radicals cations potential against DPPH, ABTS and H2O2, respectively. The correlation between AOA (antioxidant activity) and TPC (total phenolic contents) revealed to be substantial. Relative R2 values for ABTS, H2O2, and DPPH activity are 0.9974, 0.9845, and 0.9678, respectively. The in-vivo neuroprotective activities showed significant results. Our findings highlight significant antioxidant, and neuroprotective possessions of AGME attributed to powerful bioactive compounds.
Subject(s)
Antioxidants , Astragalus Plant , Neuroprotective Agents , Plant Extracts , Animals , Plant Extracts/pharmacology , Plant Extracts/chemistry , Antioxidants/pharmacology , Antioxidants/analysis , Neuroprotective Agents/pharmacology , Astragalus Plant/chemistry , Rats , Male , Rats, WistarABSTRACT
OBJECTIVE: Benzene is one of the major carcinogenic factors that can affect liver, kidneys, and lungs. Chronic inhalation of benzene vapor by petrol stations workers has been shown to have an impact on hematological parameters; thus, the present study aimed to investigate the effect of benzene exposure on petrol station workers. SUBJECTS AND METHODS: The study involved 99 participants, 50 of whom have been exposed to benzene and 49 of whom have not (control). A 5 ml blood sample in an ethylenediaminetetraacetic acid (EDTA) anticoagulant tube was collected from each subject, and a complete blood count test was used to test hematological parameters. RESULTS: The current study showed a significant decrease in red blood cells, packed cell volume, and hemoglobin in the exposed group compared to the control group. However, the amount of white blood cells was significantly increased (p < 0.0001) in the exposed group compared to the control group. Notably, there was no significant difference in platelet counts between the two groups. In terms of exposure time, subjects who have been exposed to benzene for more than a year and fewer than 10 years showed a significant decrease (p < 0.05) in RBCs indices and a significant increase (p < 0.0001) in WBCs compared to those in the control group CONCLUSIONS: Thus, the findings indicated that significant differences in hematological parameters were found in workers who were exposed to benzene compared to those who had not been exposed.
Subject(s)
Benzene , Occupational Exposure , Humans , Occupational Exposure/adverse effects , Benzene/toxicity , Adult , Male , Blood Cell Count , Hemoglobins/analysis , Hemoglobins/metabolism , Middle AgedSubject(s)
Tobacco Use Disorder , Tobacco, Smokeless , Gender Identity , Humans , Perception , Nicotiana , Tobacco Use , Tobacco, Smokeless/adverse effectsABSTRACT
With the COVID-19 outbreak, many challenges are posed before the scientific world to curb this pandemic. The diagnostic testing, treatment, and vaccine development for this infection caught the scientific community's immediate attention. Currently, despite the global proliferation of COVID-19 vaccination, the specific treatment for this disease is yet unknown. Meanwhile, COVID-19 detection or diagnosis using polymerase chain reaction (PCR)-based me hods is expensive and less reliable. Moreover, this technique needs much time to furnish the results. Thus, the elaboration of a highly sensitive and fast method of COVID-19 diagnostics is of great importance. The spectroscopic approach is herein suggested as an efficient detection methodology for COVID-19 diagnosis, particularly Raman spectroscopy, infrared spectroscopy, and mass spectrometry.
ABSTRACT
Coronavirus disease 2019 (COVID-19) is a pandemic caused by the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The spread of the virus was rapid and currently COVID-19 cases are present worldwide in 213 countries, area or territories. Researchers worldwide are working and sharing their contribution regarding epidemiology, prevention, treatment, clinical and diagnostic patterns of the COVID-19. Current review is another contribution to the current knowledge, presenting the data in organized and systematic format about the current pandemic of COVID-19. The epidemiological information presented in the paper is subject to change as new cases are diagnosed and status of active cases is updated on daily basis.
La enfermedad por coronavirus de 2019 (COVID-19) es una pandemia causada por un nuevo coronavirus, el coronavirus causante del síndrome respiratorio agudo severo 2 (SARS-CoV-2). La difusión del virus fue rápida y, actualmente, existen casos de COVID-19 a nivel mundial en 213 países, áreas o territorios. Los investigadores internacionales trabajan y comparten sus contribuciones en cuanto a epidemiología, prevención, tratamiento, patrones clínicos y diagnósticos de COVID-19. La presente revisión es otra contribución al conocimiento actual, que presenta los datos sobre la pandemia de COVID-19 en formato organizado y sistemático. La información epidemiológica presentada en el documento está sujeta a cambios, a medida que se diagnostiquen nuevos datos y se actualice el estatus de los casos activos, de manera diaria.
ABSTRACT
Sodium nitroprusside (SNP) is an antihypertensive drug with proven toxic effects attributed mainly to the production of nitric oxide (NO). Polyunsaturated fatty acids (PUFAs) are widely regarded as functional foods and have been shown to ameliorate the harmful effects of many toxicants. This study examined whether feeding of fish oil (FO)/flaxseed oil (FXO) would have any protective effect against SNP-induced hepatotoxicity and cell death. Male Wistar rats were fed either on normal diet or with 15% FO/FXO for 15 days, following which SNP (1.5 mg/kg body weight) was administered intraperitoneally for 7 days. Animals were killed after treatment, and livers were collected for further analysis. We observed that SNP significantly elevated tissue nitrite levels and lipid peroxidation (LPO) with concomitant perturbation in antioxidant defense systems accompanied with dysregulated glucose metabolism and pronounced cellular death. FO/FXO supplementation to SNP-treated rats caused reversal of tissue injury/cell death and markedly decreased LPO and improved antioxidant defense systems. FO/FXO appear to protect against SNP-induced hepatotoxicity by improving energy metabolism and antioxidant defense mechanism.
Subject(s)
Chemical and Drug Induced Liver Injury/drug therapy , Fish Oils/therapeutic use , Linseed Oil/therapeutic use , Protective Agents/therapeutic use , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Carbohydrate Metabolism/drug effects , Catalase/metabolism , Cell Death/drug effects , Cells, Cultured , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/metabolism , Dietary Supplements , Fish Oils/pharmacology , Glutathione/metabolism , Glutathione Peroxidase/metabolism , Hepatocytes/drug effects , Hepatocytes/metabolism , Linseed Oil/pharmacology , Liver/drug effects , Liver/metabolism , Male , Nitric Oxide Donors , Nitroprusside , Protective Agents/pharmacology , Rats, Wistar , Superoxide Dismutase/metabolismABSTRACT
For rapid tumor growth, cancer cells often reprogram the cellular metabolic processes to obtain enhanced anabolic precursors and energy. The molecular changes of such metabolic rewiring are far from established. Here we explored the role of mTOR (mechanistic target of rapamycin), which serves as a key regulator of cell growth, proliferation and survival, in the metabolic reprograming of cancer cells. When we inhibited mTOR in human hepatocellular carcinoma (HCC) and renal cell carcinoma (RCC) cells, using pharmacologic inhibitors or by RNA interference, we noticed shuttle of the glycolytic flux to gluconeogenesis pathway along with reduction in cellular proliferation and survival. Augmentation of gluconeogenesis was mechanistically linked to upregulation of the key gluconeogenic enzymes PCK1 and G6PC expressions, enhanced lactate dehydrogenase activity and glucose-derived lipogenesis without causing any attenuation in mitochondrial function. Interestingly, concomitant knocking down of PCK1 and not G6PC along with mTOR pathway could overcome the inhibition of cancer cell proliferation and survival. These observations were validated by identifying distinctive diminution of PCK1 and G6PC expressions in human HCC and RCC transcriptome data. Significant correlation between mTOR-dependent upregulation of PCK1 and cell death in different cancer cell lines further emphasizes the physiological relevance of this pathway. We reveal for the first time that inhibition of mTORC2 and consequent redistribution of glycolytic flux can have a prosurvival role in HCC and RCC cancer cells only in the presence of downregulation of gluconeogenesis pathway genes, thus identifying novel pivots of cancer cell metabolic rewiring and targets for therapy.
ABSTRACT
Cisplatin (CP; cis-diamminedichloroplatinum II) is a drug widely used against different types of solid tumors. Patients receiving CP, however, experience very profound and long lasting gastrointestinal symptoms. Recently, ω-3 polyunsaturated fatty acid-enriched flaxseed/flaxseed oil (FXO) has shown numerous health benefits. The present study was undertaken to investigate whether FXO can prevent CP-induced adverse biochemical changes in the small intestine of rats. A single intraperitoneal dose of CP (6 mg/kg body weight) was administered to male Wistar rats fed with control diet (CP group) and FXO diet (CPFXO group). Administration of CP led to a significant decline in the specific activities of brush border membrane enzymes both in the mucosal homogenates and in the isolated membrane vesicles. Lipid peroxidation and total sulfhydryl groups were altered upon CP treatment, indicating the generation of oxidative stress. The activities of SOD, catalase and glutathione peroxidase also decreased in CP-treated rats. In contrast, dietary supplementation of FXO prior to and following CP treatment significantly attenuated the CP-induced changes in all these parameters. FXO feeding markedly enhanced resistance to CP-elicited adverse gastrointestinal effects. The results suggest that FXO owing to its intrinsic biochemical/antioxidant properties is an effective agent in reducing the adverse effects of CP on intestine.
Subject(s)
Antineoplastic Agents/adverse effects , Antioxidants/pharmacology , Cisplatin/adverse effects , Intestine, Small/drug effects , Linseed Oil/pharmacology , Microvilli/drug effects , Alkaline Phosphatase/metabolism , Animals , Catalase/metabolism , Dietary Supplements , Glutathione Peroxidase/metabolism , Intestine, Small/metabolism , Leucyl Aminopeptidase/metabolism , Male , Microvilli/metabolism , Rats , Rats, Wistar , Sucrase/metabolism , Sulfhydryl Compounds/metabolism , gamma-Glutamyltransferase/metabolismABSTRACT
Sodium nitroprusside (SNP) a nitric oxide (NO) donor has proven toxic effects. Dietary ω-3 polyunsaturated fatty acid (PUFA) has been shown to reduce the severity of numerous ailments. Present study examined whether intake of fish oil (FO)/flaxseed oil (FXO, Omega Nutrition, St Vancouver, Canada) would have protective effect against SNP-induced toxicity. Male Wistar rats (150 ± 10 g) were used in this study. Initially animals were divided into two groups: one fed on normal diet and the other on 15% FO/FXO for 15 days. On the 16th day, SNP (1.5 mg/kg body weight) was administered intraperitoneally for 7 days daily. After 7 days animals were killed, kidneys were harvested for further analysis. SNP induced nephrotoxicity by increasing serum creatinine and blood urea nitrogen, SNP significantly decreased malate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase and malic enzyme but increased lactate dehydrogenase and glucose-6-phosphate dehydrogenase. Brush border membrane enzymes such as alkaline phosphatase, γ-glutamyl transpeptidase and leucine amino peptidase were also decreased. The activity of catalase and glutathione peroxidase decreased concomitantly with increased lipid peroxidation, indicating that the significant kidney damage has been inflicted by SNP. Feeding of FO and FXO with SNP ameliorated the changes in various parameters caused by SNP. The results of the present study suggest that ω-3 PUFA-enriched FO and FXO from seafoods and plant sources, respectively, are similarly effective in reducing SNP-induced nephrotoxicity and oxidative damage. Thus, vegetarians who cannot consume FO can have similar health benefits from plant-derived ω-3 PUFA.
Subject(s)
Dietary Supplements , Fatty Acids, Omega-3/pharmacology , Fish Oils/pharmacology , Kidney Diseases/prevention & control , Kidney/drug effects , Linseed Oil/pharmacology , Nitroprusside , Oxidative Stress/drug effects , Animals , Antioxidants/metabolism , Biomarkers/blood , Biomarkers/urine , Blood Urea Nitrogen , Carbohydrate Metabolism/drug effects , Creatinine/blood , Creatinine/urine , Cytoprotection , Disease Models, Animal , Enzymes/blood , Kidney/metabolism , Kidney/pathology , Kidney Diseases/chemically induced , Kidney Diseases/metabolism , Kidney Diseases/pathology , Lipid Peroxidation/drug effects , Lysosomes/drug effects , Lysosomes/metabolism , Male , Microvilli/drug effects , Microvilli/metabolism , Nitric Oxide/metabolism , Phosphates/metabolism , Rats , Rats, Wistar , Time FactorsABSTRACT
L-Arginine (ARG), an essential amino acid, is the endogenous source of the deleterious nitric oxide. Dietary ω-3 polyunsaturated fatty acid (PUFA)-enriched fish oil (FO) has been shown to reduce the severity of certain types of cancers, cardiovascular disease, and renal disease. Present study examined whether feeding of FO/flaxseed oil (FXO) would have protective effect against ARG-induced nephrotoxicity. ARG-induced nephrotoxicity was recorded by increased serum creatinine and blood urea nitrogen. ARG significantly altered the activities of metabolic and brush border membrane (BBM) enzymes. ARG caused significant imbalances in the antioxidant system. These alterations were associated with increased lipid peroxidation (LPO) and altered antioxidant enzyme activities. Feeding of FO and FXO with ARG ameliorated the changes in various parameters caused by ARG. Nephrotoxicity parameters lowered and enzyme activities of carbohydrate metabolism, BBM and inorganic phosphate (32Pi) transport were improved to near control values. ARG-induced LPO declined and antioxidant defense mechanism was strengthened by both FO and FXO alike. The results of the present study suggest that ω-3 PUFA-enriched FO and FXO from seafoods and plant sources, respectively, are similarly effective in reducing ARG-induced nephrotoxicity and oxidative damage. Thus, vegetarians who cannot consume FO can have similar health benefits from plant-derived ω-3 PUFA.
Subject(s)
Arginine , Dietary Supplements , Fatty Acids, Omega-3/pharmacology , Fish Oils/pharmacology , Kidney Diseases/prevention & control , Kidney/drug effects , Linseed Oil/pharmacology , Oxidative Stress/drug effects , Animals , Antioxidants/metabolism , Biomarkers/blood , Biomarkers/urine , Blood Urea Nitrogen , Carbohydrate Metabolism/drug effects , Creatinine/blood , Creatinine/urine , Cytoprotection , Disease Models, Animal , Enzymes/blood , Kidney/metabolism , Kidney/pathology , Kidney Diseases/chemically induced , Kidney Diseases/metabolism , Kidney Diseases/pathology , Lipid Peroxidation/drug effects , Lysosomes/drug effects , Lysosomes/metabolism , Male , Microvilli/drug effects , Microvilli/metabolism , Phosphates/metabolism , Rats , Rats, WistarABSTRACT
The knowledge of etiology and antibiotic resistance pattern of the organisms causing urinary tract infection is essential. This study was taken up to determine the presentation and risk factors associated with community-acquired urinary tract infection (CA-UTI). The distribution of bacterial strains isolated from these patients and their resistance pattern were also studied. This multidisciplinary prospective observational study was conducted in M. S. Ramaiah Hospital, Bangalore, between January and December, 2008. Patients who had CA-UTI confirmed by positive urine culture reports were included in the study. Statistical analysis was done using the SPSS version 16. Symptomatology and others risk factors for CA-UTI were studied in these patients and the causative organisms and their resistance patterns were recorded. Of the total 510 patients included, 57% belonged to the elderly age group (50-79 years). Fever and dysuria were the most common clinical presentation, but were not specific in predicting CA-UTI. Escherichia coli (66.9%) was the most common organism causing CA-UTIs with extended spectrum beta lactamase (ESBL) resistance seen in nearly two-thirds of these cases (42.2%). The organisms recorded least resistance against carbapenems (3.9%). A high resistance rate was seen for fluoroquinolones (74.1%). In conclusion, a high rate of ESBL-positive organisms and their resistance to commonly used antibiotics brings a concern for future options in treating these conditions.
ABSTRACT
Laparoscopic cholecystectomy is accepted as the procedure of choice for gallstone diseases but like all other procedure it is also not free from unwanted events. In this study, the authors have analyzed their experience in laparoscopic cholecystectomy (LC) and its complications and their management. Amongst the total 4957 laparoscopic cholecystectomy (LC) performed by the authors between April 1995 to May 2005 the male, female ratio was 1:5.6 (744 and 4213). 15.33%(760) of LC were carried out for the patients with acute cholecystitis. The age ranged from 9 years to 98 years. Mean operating time was 37 minutes (7 m to 187 m). Average hospital stay was 2.23 days (20 h to 7d). Peri-cholecystic adhesions including cholecysto-enteric fistulae and acute inflammation were the main reason for difficult dissection. This could be anticipated from the history of recurrent attack, high fever, severe pain and thick walled gall bladder (GB) on ultrasonography (USG). The main per-operative problem the authors came across was hemorrhage 5.2%(258), iatrogenic perforation of the gallbladder 15.12%(755) and common bile duct (CBD) injuries 0.12%(7). Conversion to open procedure was necessary in 0.68%(36) cases, most commonly due to obscure anatomy as a result of chronic inflammatory adhesions 0.56%(28), the other reasons for conversion were to deal with the CBD injury 0.04%(2), cholecysto-colic fistula 0.02%(1), unsuspected malignancy 0.06%(3) and uncontrolled bleeding 0.04%(2). The postoperative complications were port site infection and stitch granuloma 0.75%(37), bile leakage 0.08%(4), hemorrhage 0.06%(3), sub-hepatic abscess 0.02%(1), peritonitis due to gut perforation 0.04%(2) and retained bile duct stones 0.06%(3). Two deaths were due to septicemia resulting from gut perforation. Laparoscopic cholecystectomy is a safe procedure in the hands of a surgeon with adequate exposure to open surgery and properly oriented in minimally invasive surgery. Complications can be reduced to minimum if meticulous principle of dissection is followed. The unwanted events can mostly be managed laparoscopically without conversion. But decision for conversion should be taken early if there is any confusion and thus mortality and morbidity could be minimized.
Subject(s)
Cholecystectomy, Laparoscopic , Gallbladder Diseases/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Child , Cholecystectomy, Laparoscopic/adverse effects , Cohort Studies , Female , Gallbladder Diseases/etiology , Gallbladder Diseases/pathology , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Young AdultABSTRACT
Hydroxyl radical-mediated in vitro modification of human serum albumin (HSA) showed 59.2% hyperchromicity at lambdamax, 30% loss of alpha helical structure and 71.4% loss of tryptophan fluorescence. The reactive oxygen species (ROS)-modified HSA was highly immunogenic in rabbits as compare to native HSA. The antibody binding was inhibited to the extent of 97% with the immunogen as inhibitor, indicating the induction of immunogen specific antibodies. Experimentally induced antibodies against modified HSA exhibited diverse antigen binding characteristics. Native plasmid DNA, ROS-modified plasmid DNA and ROS-chromatin were found to be an effective inhibitor of induced antibody-immunogen interaction. Induced antibodies against native HSA showed negligible binding to the above mentioned nucleic acid antigens. Band shift assay reiterated the recognition towards nucleic acid antigens. Thus, the induced antibodies against *OH modified HSA resembled the diverse antigen-binding characteristics of naturally occurring systemic lupus erythematosus (SLE) anti-DNA autoantibodies.
Subject(s)
Antibodies/immunology , Hydroxyl Radical/chemistry , Immunoglobulin G/blood , Serum Albumin/chemistry , Animals , Antibody Specificity , Blood Proteins/chemistry , Circular Dichroism , Cross Reactions , DNA/chemistry , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin G/chemistry , Plasmids , Protein Binding , Protein Structure, Secondary , Rabbits , Reactive Oxygen Species/metabolism , Serum Albumin/immunology , Spectrometry, Fluorescence , Spectrophotometry, UltravioletABSTRACT
The purpose of this study was to examine the morphological and temperature changes of the apical portion of human extracted teeth treated by Nd: YAG, CO2 and Argon-lasers. Seventy-two single-rooted human teeth were studied. The root canals were prepared conventionally. Laser treatment of the apical portion of the canal was carried out by means of an optic fiber or metal tip. Temperatures were recorded thermographically. Two-thirds of the specimens were stained with black India ink and 36% silver ammonium fluoride solution. All specimens were irradiated by the three types of lasers at several intensities and the temperatures were recorded. Half of the specimens were prepared for the telescopic light microscope and for scanning electron microscopic observation, and the rest for histopathological examination by light microscope. The scanning electron microscopic evaluation showed that the laser energy vaporized the deposited debris, producing a glaze-like surface. The histopathological investigation revealed a tapered, enlarged apical lased area. All three laser devices were capable of vaporizing the debris in this way but the degree of morphological change was highly dependent on energy level and duration. The Argon-laser produced the highest temperatures.
Subject(s)
Dental Pulp Cavity/radiation effects , Lasers , Root Canal Preparation/instrumentation , Tooth Apex/radiation effects , Argon , Body Temperature , Carbon Dioxide , Dental Pulp Cavity/physiology , Hot Temperature , Humans , Microscopy, Electron, Scanning , Neodymium , Tooth Apex/physiologyABSTRACT
A gradual increase in fly ash concentrations in the normal field soil (0, 10, 20...100% volume/volume) increased the porosity, water holding capacity, pH, conductivity, C.E.C., sulphate, carbonate, bicarbonate, chloride, P, K, Ca, Mg, Mn, Cu, Zn and B. Fly ash additions to soil caused significant reductions in nitrogen content, it being almost nil in 90 and 100%. Tomato plants grown in the ash-soil mixture showed luxuriant growth with bigger and greener leaves. Plant growth, yield, (flowering, fruiting, fruit weight/plant, mean fruit weight), carotenoids and chlorophylls were mostly enhanced in the treatments with 40-80% fly ash, being optimal at 50 or 60%. From 60 or 70% onwards, the measured parameters tended to reduce. At 100% fly ash, yield (weight of fruits/plant) was considerably reduced. The boron content of tomato leaves displayed a gradual increase with fly ash addition from 20% onwards, while response of foliar nitrogen was just the opposite. The most economic level of fly ash incorporation was 40%, which improved the yield and market value of tomato fruits (mean weight) by 81 and 30%, respectively.
ABSTRACT
The biological significance of apoptosis is becoming increasingly clear. Its relevance in tumor response to treatment as well as recent evidence for its important function as a regulating mechanism in tumorigenesis has also been demonstrated. One of the most prominent biological features of apoptosis is nucleosomal DNA fragmentation. In this communication, we present a study of DNA fragmentation in Raji cells which have been subjected to hyperthermia treatment to induce apoptosis. We found that the induction and onset of fragmentation is swift, and consistent with previous reports that fragmentation must be a rapid event.
Subject(s)
Apoptosis , DNA Damage , Hot Temperature , Burkitt Lymphoma/genetics , Humans , Time Factors , Tumor Cells, CulturedSubject(s)
Tissue Plasminogen Activator/metabolism , Animals , Burkitt Lymphoma , CHO Cells , Cell Line , Cricetinae , Glycoside Hydrolases , Glycosylation , Humans , Lectins , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Tissue Plasminogen Activator/chemistry , Transfection , Tumor Cells, CulturedABSTRACT
Intermittent exposure of tomato plants (cv. Pusa Ruby) to SO(2) at 286 microg m(-3) (3 h every heavy third day for 75 days) induced slight chlorosis of leaves. At 571 microg m(-3), considerable chlorosis with browning developed on the foliage. These symptoms were more pronounced and appeared earlier on SO(2)-exposed plants infected with Meloidogyne incognita race 1 (Mi), especially in post- and concomitant-inoculation exposures. Mi and/or SO(2) significantly reduced different parameters of plant growth. Synergistic (positive) interactions between SO(2) and Mi occurred in concomitant- and post-inoculation exposures at 286 and 571 microg m(-3), respectively. In other treatments, an antagonistic (negative) interaction was observed. However, in a few cases, additive effects of SO(2) and Mi were also recorded. Intensity of root-knot (galling) was enhanced at both concentrations of SO(2), while reproduction (egg mass production) of Mi was enhanced in concomitant-inoculation exposures at 286 microg m(-3) and inhibited at 571 micro m(-3). Exposure to SO(2) and/or Mi decreased the number and size of stomata but increased the number and length of trichomes on both the leaf surfaces. Stomatal aperture was significantly wider in the plants exposed to 571 microg SO(2) m(-3) alone and in pre-, post-, and concomitant-inoculation exposures at 286 or 571 microg m(-3). Stomatal aperture was directly related to foliar injury and reductions in growth, yield, and leaf pigments.