Triphenyltin hydroxide induces changes in the oxidative stress parameters of fish

Among all organotin compounds , triphenyltin hydroxide (TPhTH) is widely used as fungicide and moluscicide in Brazil. However, the effects of TPhTH on the biochemical parameters of non-target organisms, such as fish, are little known. The aim of the present study is to assess the possible toxic effects of different concentrations of waterborne TPhTH on silver catfish belonging to species Rhamdia quelen. The fish were exposed to two different concentrations of TPhTH (1.08 and 1.70 µg/L as Sn) for 15 days and then compared to the control group (triplicate, n = 3). The antioxidant profile (catalase (CAT) and the glutathione S-transferase (GST)) and the oxidative stress parameters (TBARS-thiobarbituric acid-reactive substances and protein carbonyl (PC)) were set after the exposure to TPhTH. The TBARS level and the PC content increased in several organs of the Rhamdia quelen (brain, liver, muscle and gills) under the two concentrations of TPhTH in comparison to the control group. The CAT activity in the liver and gills has enhanced in all tested TPhTH concentrations. The GST activity increased in the brain, liver and muscle tissues under all the TPhTH concentrations. The significant changes in the biomarkers indicated that the investigated pesticide could have harmful effect on fish, in the field. However, these biomarkers were measured after the fish received doses lower than the recommended for use in agriculture.

Carbofuran promotes biochemical changes in carp exposed to rice field and laboratory conditions

Effects of carbofuran commercial formulation on oxidative stress parameters were studied in carps (Cyprinus carpio) exposed to 50µg/L for 7 and 30 days under rice field and laboratory conditions. Thiobarbituric acid reactive substance (TBARS) levels were increased in the brain of fish after 7 and 30 days under rice field and laboratory conditions. In the liver and muscle, TBARS levels increased after 7 and 30 days under laboratory conditions, whereas in rice field the levels increased only after 30 days. Protein carbonyl content in the liver increased after 7 and 30 days under both experimental conditions. Acetylcholinesterase (AChE) activity was decreased in the brain and muscle after 7 and 30 days under both experimental conditions evaluated. The superoxide dismutase (SOD) activity increased in the liver after 7 and 30 days under rice field condition, whereas under laboratory condition this enzyme increased only after 30 days. The catalase (CAT) activity in the liver decreased after 30 days under rice field condition, whereas no changes were observed under laboratory conditions. In rice field, glutathione S-transferase (GST) decreased after 7 days but increased after 30 days, whereas no change was observed in fish exposed to carbofuran under laboratory conditions. These results suggest that environmental relevant carbofuran concentrations may cause oxidative stress, affecting biochemical and enzymatic parameters on carps. Some parameters could be used as biomarkers to carbofuran exposure.

Toxic effects of penoxsulam herbicide in two fish species reared in southern Brazil

Toxic effects of penoxsulam herbicide on acetylcholinesterase, thiobarbituric acid-reactive substances and protein carbonyl were studied in silver catfish (Rhamdia sp.) and carp (Cyprinus carpio). Acetylcholinesterase activity was inhibited in both brain and muscle tissue, with the inhibition being greater in carp than in silver catfish. The levels of malondialdehyde (MDA), an indicator of lipid peroxidation, decreased in silver catfish brain tissue, but increased in the carp brain. MDA also increased significantly in muscle tissue of silver catfish. The levels of protein carbonyl, another measure of oxidative damage, increased in the brain of both fish species, and in the muscle of carp. However, silver catfish exhibited a decrease in muscle protein carbonyl. It appears that silver catfish may possess better mechanisms of defense against penoxsulam toxicity than carp.

Oxidative stress in carp exposed to quinclorac herbicide under rice field condition

This study evaluated parameters of oxidative stress and antioxidant profile in fish after herbicide exposure. Cyprinus carpio were exposed to quinclorac (initial concentration 344.60μg/L) for 7, 30, and 90 days under rice field condition. Thiobarbituric acid-reactive substances (TBARS) were evaluated in brain, liver and muscle tissues, and protein carbonyl in liver. Enzymatic parameters such as catalase (CAT) and gluthatione S-transferase (GST) activities also were studied in liver. TBARS levels fluctuated in the brain showing increase in 7 days and decrease in 30 days, while in liver it was observed increase in 7 and 30 days, as well as in muscle after 30 and 90 days. The protein carbonyl was also increased after 30 and 90 days of herbicide exposure. CAT and GST activities were decreased after 30 and 90 days, respectively. The alterations observed suggest that a commercial formulation containing quinclorac causes oxidative damage in different tissues of carp after a long time of exposure. This study pointed out the importance of quinclorac toxicity considering the concentration used in rice fields.

Effects of the commercial formulation containing fipronil on the non-target organism Cyprinus carpio: implications for rice-fish cultivation

The aim of this research was to evaluate possible toxic effects of commercial formulation containing fipronil on Cyprinus carpio tissues under rice field conditions. Antioxidant profile (SOD, catalase, glutathione S-transferase), oxidative stress parameters (thiobarbituric acid-reactive substances, protein carbonyl), and growth were investigated in carp exposed to fipronil under rice field conditions for 7, 30, and 90 days. Waterborne insecticide concentrations were measured and the detectable concentration of fipronil was observed up to 45 day after application. Common carp survival and growth was not affected by fipronil. Liver superoxide dismutase activity was enhanced while liver catalase activity was inhibited at 7, 30, and 90 days. Alterations were not observed in the glutathione S-transferase activity in any experimental periods. Protein carbonyl increased only after 30 and 90 days of exposure. The thiobarbituric acid-reactive substances levels were enhanced in all analyzed tissues (liver, muscle, and brain) and periods of exposure. This study demonstrates that fipronil insecticides cause alterations in the biochemical parameters in different tissues of carp without affecting the growth or the survival of the fish.

Tissue biochemical alterations of Cyprinus carpio exposed to commercial herbicide containing clomazone under rice-field conditions

Field and laboratory experiments were performed to evaluate toxicological responses of Cyprinus carpio exposed to the commercial herbicide clomazone (500 mg l(-1)). Fish were exposed to 0.5 mg l(-1) of the formulated herbicide for 7, 30, and 90 days. Fish were exposed to clomazone in field conditions (7, 30, or 90 days trapped in submersed cages together with rice crops) and in laboratory conditions where the fish were placed in 45-l tanks with tap water only for 7 days. Fish exposed for 7, 30, or 90 days showed no alterations in acetylcholinesterase (AChE) activity under field conditions. Under laboratory conditions, decreased muscle AChE activity was observed only after 7 days of exposure. During the same evaluation period (7 days), oxidative stress parameters changed under both field and laboratory conditions; however, metabolic parameters were altered only under field conditions. Disorders in oxidative stress parameters and metabolism were evident in different tissues up to day 90 after treatment. These overall results show that AChE activity changed only under laboratory conditions. Oxidative stress, along with metabolic parameters, may be good indicators of herbicide contamination in C. carpio under rice-field conditions.

Toxicological responses of Cyprinus carpio exposed to a commercial formulation containing glyphosate

The effects of commercial glyphosate herbicide formulation on the activity of acetylcholinesterase (AChE) enzyme and oxidative stress were studied in Cyprinus carpio exposed for 96 h to 0.0, 0.5, 2.5, 5.0 and 10.0 mg/L and then allowed to equal recovery period in water without herbicide. The activity of AChE was inhibited in the brain and in the muscle after exposure. However, after recovery period brain and muscle AChE activity increased. Brain thiobarbituric acid reactive species (TBARS) were measured as an indicator of oxidative stress. Increased TBARS levels were observed with all concentrations tested of the glyphosate formulation, and remained increased after the recovery period. The results recorded clearly indicate lipid peroxidation and anti-AChE action induced by Roundup(®) exposure.

Roundup effects on oxidative stress parameters and recovery pattern of Rhamdia quelen

Antioxidant enzymes and oxidative stress indicators were evaluated in fish exposed to different concentrations of the herbicide Roundup 48% (Monsanto, St. Louis, MO): control (none), 0.45, or 0.95 mg/l. After exposure for 8 days to herbicide, fish were transferred to clean water for a recovery response period (also 8 days). Herbicide increased thiobarbituric acid reactive species in liver and muscle at the higher concentration and in the brain at both concentrations. Protein carbonyl in liver increased after exposure. Catalase (CAT) and superoxide dismutase (SOD) activities and ascorbic acid levels in liver did not change in fish exposed to both concentrations. Glutathione S-transferase (GST) levels decreased at both concentrations. The nonprotein thiol levels decreased at the 0.95 mg/l concentration. During the recovery period, some of the parameters that had altered, such as protein carbonyl content, later recovered. However, some enzymes reacted during this period, e.g., GST increased its activity, possibly indicating a compensatory response against the toxic conditions. In contrast, CAT and SOD activities decreased during the recovery period, indicating herbicide toxicity. Oxidative stress that occurred during the exposure period was likely due to the increased lipid peroxidation and protein carbonyl content. The results concerning oxidative and antioxidant profiles indicate that short-term exposure to herbicide is capable of causing oxidative stress in fish tissues.

Toxicological responses of Cyprinus carpio after exposure to a commercial herbicide containing imazethapyr and imazapic

Cyprinus carpio was exposed to imazethapyr and imazapic at laboratory and at field conditions. The laboratory experiment was carried out for 7 days and at rice field for 7, 30 and 90 days. Oxidative stress parameters and antioxidant profile were studied as well as metabolic parameters. After 7 days, brain AChE activity increases in laboratory and field, but in muscle, reduction was observed only in laboratory. At the same period, brain and muscle TBARS and liver CAT increase in the laboratory. Metabolic parameters showed changes in both conditions and exposure periods. After 30 days in rice field, brain AChE activity decreases and in muscle it was enhanced. After 90 days in field, only muscle AChE activity was reduced. The disorders in oxidative stress parameters and metabolism remained, indicating mainly a protein catabolism. This study pointed out short- and long-term effects of rice herbicides at environmentally relevant concentrations on toxicological parameters in tissues of C. carpio.

Effects of water cadmium concentrations on bioaccumulation and various oxidative stress parameters in Rhamdia quelen

The effects of sublethal cadmium concentrations on oxidative stress parameters were evaluated in Rhamdia quelen. The fish were exposed to 0.44, 236, and 414 μg l⁻¹ cadmium for 7 and 14 days, followed by the same time periods for recovery. Enzymes, such as catalase (CAT), superoxide dismutase (SOD), and glutathione S-transferase (GST), and indicators of oxidative stress, such as thiobarbituric acid-reactive species (TBARS) and protein carbonyl, were verified in fish tissues. In addition, the accumulation of cadmium was evaluated in these tissues. Our results indicate that CAT and GST levels decreased in gills after exposure periods associated with increased TBARS levels. In hepatic tissue, CAT, GST, TBARS, and protein carbonyl levels increased after 7 days of exposure, whereas SOD activity decreased after exposure for 14 days. In the kidney, TBARS levels decreased after exposure for 7 days and increased after exposure for 14 days. During the recovery periods, some variations persisted in gills, liver, and kidney. Cadmium accumulation was most significant in liver, followed by kidney and gills. These results indicate that cadmium concentrations studied invoke a stress response in silver catfish.

Acetylcholinesterase activity, lipid peroxidation, and bioaccumulation in silver catfish (Rhamdia quelen) exposed to cadmium

Cadmium is a metal with no biological function in superior organisms and it is very toxic even at very low concentrations. Thus the objective of this study was to verify some toxicological parameters in silver catfish (Rhamdia quelen) exposed to cadmium. In this study, silver catfish was exposed to 0 (control), 0.236, and 0.414 mg L(-1) cadmium for 7 and 14 days, followed by the same periods of recovery. The effects of cadmium on acetylcholinesterase (AChE) activity and metal accumulation in brain and muscle were verified. Thiobarbituric acid-reactive substance (TBARS) formation was evaluated in brain. An increase in TBARS levels was verified after exposure and recovery periods and AChE activity in brain was reduced after 14 days of exposure. These parameters did not return to control values after the recovery period. In muscle AChE was altered during both exposure periods. Alterations in AChE activity may be a good indicator of cadmium contamination in R. quelen.

Malignancy associated changes in squamous epithelium of the head and neck region

Subtle cellular changes are known to exist in normal host tissue adjacent to tumours. These are called malignancy associated changes (MAC). To get more insight into the degree of expression and local spread of such changes we performed high resolution image cytometry on visually normal intermediate cell nuclei in smears from patients with laryngeal or pharyngeal squamous cancer. The smears were taken from the tumour surface, from a border region of the tumour and from a distant unsuspicious buccal site. In addition buccal smears from healthy control persons were examined. In a pilot study smears from 12 cancer patients and 11 control persons and in a succeeding validation study 63 controls, 18 non-tumour patients and 25 cancer patients were investigated. In both studies the occurrence of MACs was demonstrated quantitatively. In cancer patients normal appearing intermediate cells from the three different sampling sites could be discriminated with 65% in the pilot study and with 53% correct classification in the validation study. In addition the influences of smoking behaviour and sex were investigated in the control group. Only in the latter case there was a significant difference between female and male with a 63% correct cell and 71% correct specimen classification.

Controlled study of brodimoprim and cephalexin in the treatment of patients with acute sinusitis in general practice

Brodimoprim, a new dehydrofolate reductase inhibitor, was compared with cephalexin in the treatment of patients with acute sinusitis. A total of 49 patients were randomly assigned to receive either brodimoprim 200-mg tablets once a day (400 mg on the first day as a loading dose) or cephalexin 500-mg tablets three times a day for 8 to 12 days. Nearly all patients treated were judged clinically cured/improved; in fact, only one failure (in the cephalexin group) was noted. In the 45 assessable patients, the time until disappearance of the symptoms and the duration of treatment did not differ significantly between the two groups. A bacteriologic examination was performed in all patients at baseline as well as at the end of therapy. Bacteriologic eradication was obtained in 88% of the patients treated with brodimoprim and in 76% of those receiving cephalexin. Both compounds were generally well tolerated (one patient in the brodimoprim group complained of skin reactions). These results suggest that once-daily treatment with brodimoprim represents safe and effective therapy for adults with acute bacterial sinusitis.

[The feasibility of pretherapeutic diagnosis of malignant pharyngeal processes using high-frequency cineradiography]

The differentiation between stage T3 and stage T4 pharyngeal tumors is of crucial importance for the proper therapeutic approach (surgery, surgery with consecutive radio- or radiochemotherapy, chemotherapy). The clinical relevance of the additional information provided by cineradiography was evaluated in combination with the endoscopic and computed tomographic results. We performed static and dynamic pharyngography with mono- and double-contrast-methods in four planes, including pharyngeal distension (Valsalva's and Müller's maneuver) and phonation. For the dynamic study, high-speed cineradiography (35 mm film, 50 frames/s) was used. Twenty-three patients with histologically proven neoplasms were examined. It was determined that surgery was technically feasible in 4 out of 14 patients who were previously presumed to have inoperable tumors. In 2 cases, an extension of the tumor mass was seen by cineradiography (results proven intraoperatively).

[Principles of therapy with fission neutrons and boron neutron capture therapy for radioresistant head-neck malignancies]

Neutron therapy has proven to be clinically useful in cases of advanced, slow-growing radioresistant head and neck carcinoma. Therapeutic effects might be based on direct DNA damaging and thus immediate cell-killing, on the generation of free oxygen radicals and, among others, on the fact that heavy particle radiation is said to be less dependent on the presence of oxygen than gamma rays, i.e. on a lower oxygen enhancement ratio (OER). The smaller difference in reaction between oxygenated and nonoxygenated cells could entail advantages as well as disadvantages, depending on the characteristics of the tumor cell population and of the normal tissue. It is therefore essential to select patients and tumours with an expectedly high therapeutic gain factor. Fission neutrons for tumour therapy: As evaluated by several in vitro and in vivo studies (11/13) the biological efficiency (RBE) of the RENT (Reactor Neutron Therapy) beam in Munich seems to be among the highest of all clinically used neutron beams. For a single dose range between 2 and 8 Gy the RBE for chronic radiation damage is relatively small (2). Consequently, patients with recurrent or metastatic carcinomas of the head and neck are treated with a single dose of 200-250 cGy after previous surgery and/or combined radiochemotherapy. The main limitation of fission neutrons is the small penetration depth. Possibilities of clinical implementation of boron neutron capture therapy (BNCT) in otorhinolaryngology: In near surface tumours it is possible to administer high doses of 10boron not selectively, i.e. no selective tumour-seeking compound is needed. Animal experiments with intratumoural injection of 10boron glycine have shown a strong effect on tumour growth delay (18).(ABSTRACT TRUNCATED AT 250 WORDS)

[The weighting of SE, IE and GE sequences in tumors of the head and neck]

In a review of 82 patients having different benign and malignant head and neck tumours we studied the value of spin echo (SE), inversion echo (IE) and gradient echo (GE) sequences. The strong T1 weighted IE mode is highly sensitive to demonstrate pathological tissue. Tumour diagnosis was in 20% and lymph node diagnosis in 29% better than T2 weighted SE sequences. According to this experience we choose the IE mode as the first one for all patients examined for tumour staging. All other sequences and orientations are planned on this tomograms knowing the location of the tumour and lymph nodes. T1 weighted SE mode is indispensable and should be recorded in transversal orientation, covering the whole head and neck region. This mode has the best imaging of anatomical structures as the known fatty limitations. The best differentiation of the tumour is usually obtained after contrast enhancement by i.v. Gd-DTPA. The highest contrast enhancement is seen on T1 weighted GE tomograms, which we prefer. T2 weighted SE sequences are less sensitive than IE sequences and T1 weighted tomograms after Gd-DTPA to show the tumour. The T2 weighted SE mode cannot be replaced by the T2 weighted GE mode having a better signal to noise ratio. To minimise the scan-time of T2 weighted SE mode, only one measurement is performed; the quality of the tomograms is satisfactory.

[Squamous cell carcinoma-associated antigen (SCC) as a tumor marker in the initial diagnosis of carcinomas of the head and neck region. Results of a prospective study after 24 months]

The serum--SCC antigen levels of patients with head and neck tumors were studied prospectively to determine their value in the initial diagnosis of head- and neck-cancer patients. Serum concentrations above 2 ng/ml are considered abnormal. Preliminary results of the study after a 12-month period have been reported elsewhere (1). The final results of the study show an increased percentage (53%) of pathologic findings, mostly due to the increasing number of advanced stage tumors. High serum levels were found in 60% of the T4-tumors (Fig. 4a). Well differentiated carcinomas seem to be associated with the antigen more frequently than poorly differentiated tumors (Fig. 5). SCC antigen levels were examined as many as five times before the start of treatment (85 patients), and in one-third of those cases the differences between the serum levels exceeded 1 ng/ml. As far as 85% specificity is concerned, the ROC-curve shows a sensitivity of only 40% (Fig. 2) which, in addition to the fact that the antigen was most frequently found in cases of advanced tumors, indicates that the usefulness of the SCC antigen as a tumor marker for head and neck cancer must still be regarded as low.

[Comparative studies of the quality of the esophageal voice following laryngectomy: the insufflation test and reverse speech audiometry]

We carried out a transnasal insufflation test according to Blom and Singer on 27 laryngectomy patients as well as a speech communications test with the help of reverse speech audiometry, i.e. the post laryngectomy telephone test according to Zenner and Pfrang. The combined evaluation of both tests provided basic information on the quality of the esophagus voice and functionability of the speech organs. Both tests can be carried out quickly and easily and allow a differentiated statement to be made on the application possibilities of a esophagus voice, electronic speech aids and voice prothesis. Three groups could be identified from our results: 1. Insufflation test and reverse speech test provided conformable good or very good results. The esophagus voice was well understood. 2. Complete failure in the insufflation and telephone tests calls for further examinations to exclude any spasm, stricture, divertical and scarred membrane stenosis as well as tumor relapse in the region of the pharyngo-esophageal segments. 3. Organic causes must be looked for in the area of the nozzle as well as cranial nerve failure and social-determined causes in the case of normal insufflation and considerably reduced speech communication in the telephone test.

[Classification and documentation of malignoma of the inner nose and paranasal sinuses]

In the fourth edition of the UICC guidelines for TNM classification (valid since January 1st, 1987), the organ "maxillary sinus" has been indicated for the first time within the category "head and neck". This decision made by UICC to consider the maxillary sinus alone is insufficient and contradictory--the reasons are discussed. The AO (Working Group for Clinical Oncology)/ORL will therefore maintain its classification considering the functional unity of the organ "inner nose and paranasal sinuses", which has proved its great worth in 1363 cases treated during the period from 1972 through 1987. There is no reason to abandon the classification of malignomas of the inner nose and the paranasal sinuses and to replace it by a UICC guideline only valid for carcinomas of the maxillary sinus which cannot convince. The practicability of classification and documentation has certainly be improved since the introduction of organ-specific questionnaires (first ascertainment, subsequent ascertainment).

[Squamous cell carcinoma antigen. Current clinical value of a new tumor marker in head and neck cancer; preliminary results of a prospective study after 12 months]

The serum SCC antigen levels of patients with head and neck tumours are being studied in a prospective study to evaluate their clinical relevance. Concentrations above 2 ng/ml are considered to be abnormal. Preliminary results of the study after a 12-month period including 167 patients are reported: In only 28% of the patients with actual carcinoma of the head and neck the serum levels were pathological (Fig. 6), most commonly in oropharyngeal tumours (nearly 50%). The incidence of abnormal SCC-antigen concentration only rarely increased with increasing tumour extension (Fig. 7), but to a considerably greater extent in well-differentiated than in poorly or non-differentiated squamous cell carcinomas (Fig. 8). Tendencies, but no statistically significant correlation, were found between the Karnofsky index and the serum levels (Fig. 9) - as well as between the time of remission after successful tumour treatment and decreasing serum concentrations (Fig. 10). At the time of recurrence of the tumour, SCC-antigen serum levels had not been able to predict the clinical recurrence (Fig. 11). Since the assessment of SCC-antigen concentration is neither highly specific nor sensitive, the usefulness of this tumour marker test must be--at least according to the present state of the art--regarded as rather low.

[Report of experiences (1974-1986) in classification and site distribution of malignant tumors of the organs of the inner nose and paranasal sinuses. A retrospective review of over 1,296 cases]

The 4th edition of the UICC classification of the TNM system came into force on 1st January 1987. New rules have been established for the classification of maxillary sinus tumors. We have compared these to the classification system used by the AO/HNO for all the sinuses and the nose. From a review of the world literature and analysis of 1296 patients registered in the years 1974 to 1986, it became clear that less than 60% of all malignant tumors of the nasal cavity and sinuses are primarily located in the maxillary sinuses. Furthermore, the primary site is often hard to define because of the high rate of T3 and T4 tumors (approx. 70%).

[New and changed guidelines in the TNM system of head and neck tumors]

Starting on the 1st of January 1987, the 4th edition of the UICC classification of the TNM-system is to be applied. Only slight changes have been made in the rules for the larynx and the skin, whereas the classification of the nodal status has undergone a more profound change. New rules have been established for the classification of salivary gland and maxillary sinus tumours, including a stage grouping for the salivary glands. The R-classification is new and changes have been made in the histological grading. The head and neck part of the edition is presented. The classification for the maxillary sinuses is compared to a personal system covering all the sinuses and the nose: its usefulness has been proven by successful documentation of 1224 cases.