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The tissue distribution of rotenoid residues was determined in tissues of common carp Cyprinus carpio (88.2 g), bluegills Lepomis macrochirus (47.9 g), and yellow perch Perca flavescens (67.7 g) after the fish were exposed to 50 μg/L of rotenone-6a-14C (15.9 x 104 Bq/μM). Exposures were terminated 1 h after the fish were moribund and failed to respond to gentle prodding. The fish were dissected, and various tissues were oxidized to determine 14C-rotenone accumulation and distribution. Major rotenone metabolites were identified by gradient-elution high performance liquid chromatography. The exposure time required for fish to reach total incapacitation was 3 h for bluegills and yellow perch, and 11.25 h for common carp. The mean rotenoid concentrations (μg/100 g fish) in the whole body were 22.4 in yellow perch, 39.7 in bluegills, and 107.8 in common carp. The percentage of rotenone-derived 14C activity was higher in the carcass components than in the head or viscera; the skin and bone contained about 60% of the carcass activity. The highest relative rotenoid concentrations were found in the liver, bile, gills, brain, and heart. Percentages of total rotenoid material as parent rotenone were highest in yellow perch (70.0 in the viscera and 84.4 in the fillet), followed by those for bluegills (22.7 and 27.8) and common carp (9.7 and 48.5). [ABSTRACT FROM AUTHOR]

Rainbow trout, Oncorhynchus mykiss (Walbaum), eggs were exposed to [methano-14C] malachite green chloride on day 0 and on every third day thereafter through day 24, with a final treatment administered to fry on day 31. Eggs or fry were sampled before each treatment, and at selected times from day 31 to day 59. Malachite green equivalence in eggs and fry was determined by sample oxidation and liquid scintillation counting. Total malachite green residues increased throughout the exposure period to 0.271 ± 0.042 µg g--1 (&xmacr; ± SD) on day 31. Residues declined to 0.055 ± 0.011 µg g-1 on day 59. The depuration phase declined monoexponentially with a half-life of 13.3 days for the absolute amount (µg sample-1) and a half-life of 9.7 days for the concentration of malachite green residues (µg g-1). Growth dilution accounted for the 25% increase in the elimination (9.7 days) of malachite green residues. Extracts from treated eggs and fry were analysed by reversed-phase liquid chromatography. Three peaks were resolved in treated eggs: chromatic malachite green, leuco malachite green and an unknown polar metabolite. Only two peaks were resolved in the fry: leuco malachite green and the unknown polar metabolite. The most prominent residue in all samples was leuco malachite green. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increased focus on the teaching of small-animal dentistry to veterinary students in order to address the recognized gap between dental skill training and the expectations of employers regarding the competencies of new graduates in this field. In this study, third-year veterinary students were trained in three canine dental core skills using either a high-fidelity model (Group A) or video instruction (Group B). An objective structured clinical examination was used to assess skill acquisition and questionnaires were distributed in order to assess student confidence and perceptions related to small-animal dentistry practice and related skills before and after the training. All results were compared between the two groups. Group A outperformed Group B in skill acquisition ( p < 0.001) and there was greater improvement in skill confidence for Group A than Group B ( p < 0.001). There was no statistical difference in perceptions related to small-animal dentistry between the two groups after the training ( p ≥ 0.1). Group A rated their training experience more highly than Group B ( p < 0.001). Although dental skill acquisition shows greater improvement when training is provided by models rather than video instruction, a blended approach to teaching dental skills is likely to be the best approach to optimizing dental skill acquisition.

Clinical application of a demineralized freeze-dried cortical bone membrane allograft (DFBMA) for treatment of intra(infra)bony periodontal pockets in dogs was evaluated. The mean pre-treatment periodontal probing depth equaled 7.2-mm. Post-treatment probing depths in all 11 cases were normal, with a mean periodontal probing gain of 5.4-mm. Guided tissue regeneration using a commercially available veterinary canine DFBMA and canine demineralized freeze-dried bone allograft (DFDBA) resulted in clinically significant periodontal attachment gains. The gain of new periodontal tissue attachment was statistically significant (P < 0.0001). The commercially available veterinary allograft products predictably increased new periodontal attachment without any identified membrane sequelae in these 11 cases.

The role of odontogenic infection as an etiology for lymphoplasmacytic rhinitis in dogs was evaluated. An association between odontogenic infection and inflammatory rhinitis was identified in 55% of cases evaluated. Odontogenic infection was unlikely or undetermined in 10% and 35% of the cases, respectively. Cases of lymphoplasmacytic rhinitis had roentgen signs associated with endodontic disease, periodontal disease, or retained tooth roots in 60%, 45%, and 25% of the cases, respectively. A collaborative team based approach assessing inflammatory nasal disease is recommended. Based on the history and signalment of the individual patient, diagnostic modalities should be chosen wisely. In some cases, oral examination and intraoral radiographs may be a more direct and cost effective approach for diagnosis and treatment of inflammatory rhinitis.

Chloramine-T is an effective drug for controlling fish mortality caused by bacterial gill disease. As part of the data required for approval of chloramine-T use in aquaculture, depletion of the chloramine-T marker residue (para-toluenesulfonamide; p-TSA) from edible fillet tissue of fish must be characterized. Declaration of p-TSA as the marker residue for chloramine-T in rainbow trout was based on total residue depletion studies using a method that used time consuming and cumbersome techniques. A simple and robust method recently developed is being proposed as a determinative method for p-TSA in fish fillet tissue. The proposed determinative method was evaluated by comparing accuracy and precision data with U.S. Food and Drug Administration criteria and by bridging the method to the former method for chloramine-T residues. The method accuracy and precision fulfilled the criteria for determinative methods; accuracy was 92.6, 93.4, and 94.6% with samples fortified at 0.5X, 1X, and 2X the expected 1000 ng/g tolerance limit for p-TSA, respectively. Method precision with tissue containing incurred p-TSA at a nominal concentration of 1000 ng/g ranged from 0.80 to 8.4%. The proposed determinative method was successfully bridged with the former method. The concentrations of p-TSA developed with the proposed method were not statistically different at p < 0.05 from p-TSA concentrations developed with the former method.

Solution-focused brief therapy (SFBT) is a new and increasingly used therapeutic approach that focuses on helping clients construct solutions rather than solve problems. The approach evolved in a clinical context amid many anecdotal reports of success from both therapists and clients, but it has not been subjected to controlled empirical testing until very recently. In this article we critically review all of the controlled outcome studies of SFBT to date (N = 15) to assess the extent to which SFBT has received empirical support. Five studies were well-controlled and all showed positive outcomes--four found SFBT to be better than no treatment or standard institutional services, and one found SFBT to be comparable to a known intervention: Interpersonal Psychotherapy for Depression (IPT). Findings from the remaining 10 studies, which we consider moderately or poorly controlled, were consistent with a hypothesis of SFBT effectiveness. We conclude that the 15 studies provide preliminary support for the efficacy of SFBT but do not permit a definitive conclusion. Our critique highlights areas where methodology in future studies can be strengthened to provide more conclusive evidence of SFBT efficacy.

The effect of temperature (7 degrees C and 16 degrees C) on the extent of accumulation and the elimination of benzocaine (BNZ) and its metabolite, acetylated benzocaine (AcBNZ), in the fillet tissue of rainbow trout was investigated. Residues were measured after bath exposure to an anesthetizing concentration of benzocaine (30 mg/l for 5 min) followed by a maintenance concentration (15 mg/l for 30 min). Immediately after exposure, the BNZ concentration in fillet tissue was approximately 27 micrograms/g at both temperatures; AcBNZ was 0.3 microgram/g at 7 degrees C and 0.6 microgram/g at 16 degrees C. The rates for elimination (alpha and beta) of BNZ and AcBNZ were not significantly different between the two temperatures. Terminal half-lives of elimination for BNZ were 1.62 h at 7 degrees C and 1.63 h at 16 degrees C; half-lives for AcBNZ were 2.36 h at 7 degrees C and 2.77 h at 16 degrees C.

Chloramine-T (N-sodium-N-chloro-p-toluene-sulfonamide) is a candidate therapeutic drug for treating bacterial gill disease, a predominant disease of a variety of fish species. Research has been initiated to obtain the U.S. Food and Drug Administration's (FDA) approval for the use of chloramine-T on a variety of fish species. An attribute of a therapeutic aquaculture drug that must be characterized before the FDA approves its use is depletion of the drug's marker residue (the drug's parent compound or metabolite of highest concentration in an edible tissue). para-Toluenesulfonamide (p-TSA) is the primary degradation product and marker residue for chloramine-T in rainbow trout. To conduct residue depletion studies for chloramine-T in fish, a robust analytical method sensitive and specific for p-TSA residues in edible fillet tissue from a variety of fish was required. Homogenized fillet tissues from rainbow trout (Oncorhynchus mykiss), walleye (Stizostedion vitreum), and channel catfish (Ictalurus punctatus) were fortified at nominal p-TSA concentrations of 17, 67, 200, 333, and 1000 ng/g. Samples were analyzed by isocratic reversed-phase liquid chromatography (LC) with absorbance detection at 226 nm. Mean recoveries of p-TSA ranged from 77 to 93.17%; relative standard deviations ranged from 1.5 to 14%; method quantitation limits ranged from 13 to 18 ng/g; and method detection limits ranged from 3.8 to 5.2 ng/g. The LC parameters produced p-TSA peaks without coelution of endogenous compounds and excluded chromatographic interference from at least 20 chemicals and drugs of potential use in aquaculture.

Oxytetracycline (OTC) is a drug approved by the U.S. Food and Drug Administration (FDA) to control certain diseases in salmonids and catfish. OTC is also a likely control agent for diseases of other fish species and for other diseases of salmonids and catfish not currently on the label. One requirement for FDA to extend and expand the approval of this antibacterial agent to other fish species is residue depletion studies. The current regulatory method for OTC in fish tissue, based on microbial inhibition, lacks sensitivity and specificity. To conduct residue depletion studies for OTC in fish with a liquid chromatographic method, a bridging study was required to determine its relationship with the official microbial inhibition assay. Triplicate samples of rainbow trout fillet tissue fortified with OTC at 0.3, 0.6, 1.2, 2.4, 4.8, and 9.6 ppm and fillet tissue with incurred OTC at approximately 0.75, 1.5, and 3.75 ppm were analyzed by high-performance liquid chromatography (HPLC) and the microbial inhibition assay. The results indicated that the 2 methods are essentially identical in the tested range, with mean coefficients of variation of 1.05% for the HPLC method and 3.94% for the microbial inhibition assay.

The approved use of oxytetracycline (OTC) in U.S. aquaculture is limited to specific diseases in salmonids and channel catfish. OTC may also be effective in controlling diseases in other fish species important to public aquaculture, but before approved use of OTC can be augmented, an analytical method for determining OTC in fillet tissue from multiple species of fish will be required to support residue depletion studies. The objective of this study was to develop and validate a liquid chromatographic (LC) method that is accurate, precise, and sensitive for OTC in edible fillets from multiple species of fish. Homogenized fillet tissues from walleye, Atlantic salmon, striped bass, white sturgeon, rainbow trout, and channel catfish were fortified with OTC at nominal concentrations of 10, 20, 100, 1000, and 5000 ng/g. In tissues fortified with OTC at 100, 1000, and 5000 ng/g, mean recoveries ranged from 83 to 90%, and relative standard deviations (RSDs) ranged from 0.9 to 5.8%. In all other tissues, mean recoveries ranged from 59 to 98%, and RSDs ranged from 3.3 to 20%. Method quantitation limits ranged from 6 to 22 ng/g for the 6 species. The LC parameters produced easily integratable OTC peaks without coelution of endogenous compounds. The method is accurate, precise, and sensitive for OTC in fillet tissue from 6 species of fish from 5 phylogenetically diverse groups.

The pharmacokinetics of benzocaine during bath exposures at 1 mg/L were determined in rainbow trout acclimated at 6 degrees C, 12 degrees C or 18 degrees C for at least 1 month. Individual fish were exposed to benzocaine in a recirculating system for 4 h and pharmacokinetic parameters were estimated in a unique manner from the concentration of benzocaine in the bath water vs. time curve. Elimination from plasma was also determined after the 4 h exposure. The uptake clearance and metabolic clearance increased with increased acclimatization temperatures (uptake clearance 581 +/- 179 mL/min/kg at 6 degrees C and 1154 +/- 447 mL/min/kg at 18 degrees C; metabolic clearance 15.2 +/- 4.1 mL/min/kg at 6 degrees C and 22.3 +/- 4.2 mL/min/kg at 18 degrees C). The apparent volume of distribution had a trend for increasing with temperature that was not significant at the 5% level (2369 +/- 678 mL/kg at 6 degrees C to 3260 +/- 1182 mL/kg at 18 degrees C). The elimination half-life of benzocaine in plasma was variable and did not differ significantly with temperature (60.8 +/- 30.3 min at 6 degrees C to 35.9 +/- 13.0 min at 12 degrees C). Elimination of benzocaine from rainbow trout is relatively rapid and even more rapid at higher acclimatization temperatures based on calculated metabolic clearances and measured plasma concentrations, but was not evident by measurement of terminal plasma half-lifes.

Production in US aquaculture is limited by the few FDA-approved drugs available for use. The problem is compounded by the high costs and long time frames associated with extending the approved label of an existing drug to treat additional fish species. An FDA approved crop grouping plan could significantly reduce the costs associated with extending or expanding the label of a currently approved drug to other species. Before FDA could sanction such a plan, they require scientific data with which to make an informed decision. Under a crop grouping plan, a surrogate fish species would represent a single group of fish for the purposes of gaining drug approvals. The concept, if practical, would conserve substantial public resources expended to gain drug approvals and yet give regulators assurance that the extended label use provides necessary regulatory safeguards to protect human food safety and the environment. A crop grouping plan should include development of a data base that is sufficiently sensitive to discriminate differences of one group from another and yet would be able to identify potential similarities between like-species for grouping. The proposed crop grouping action plan should include data sets for fish grouped by temperature preference, activity level, and phylogenetic classification. Initially, two representative species would be identified for testing as surrogates for candidate groups; rainbow trout representing a coldwater, active, and conservative phylogenetic group, and channel catfish representing a warmwater, relatively sedentary and more phylogenetically advanced group. Additional species representing more primitive (sturgeon) and more advanced (striped bass and walleye) groups would be added. A waterborne (benzocaine) and an orally administered drug (sarafloxacin) would initially be tested among the major species groups. The integrity of the group will be tested by comparing the variability of response between major species against variability within cohort species identified for inclusion within each specific group.

A liquid chromatographic method is described for analysis of benzocaine (BZ), a proposed fish anesthetic, in rainbow trout plasma. Mean recoveries of BZ from plasma samples fortified at 44-10 100 ng/mL were 96-100%. The method detection limit is 10 ng/mL, and the limit of quantitation is 37 ng/mL. Acetylation of BZ occurs in whole blood after storage at room temperature (i.e., 21 degrees C) for 10 min. However, no acetylation of BZ was detected in plasma samples held at room temperature for 4 h. Mean method precision for plasma samples with incurred BZ residue is similar to that for fortified samples in the same concentration range (relative standard deviations of 0.9 and 1.2%, respectively).

This article describes the development of BRIEFER I and BRIEFER II, expert systems that advise the therapist on selecting, designing, and developing an intervention at the end of the first therapy session. The process of developing expert systems has aided us in describing what brief therapists do, in modeling the intervention design process, and in training brief therapists.

The effects of surgery and anesthesia on concentrations of plasma epinephrine (E), norepinephrine (NE), and dopamine (DA) were investigated in rainbow trout fitted with dorsal aorta cannulae. Baseline catecholamines (CA) concentrations, established in resting rainbow trout, were 1.55 +/- 0.90 pmol/ml (mean +/- SD) for E, 2.07 +/- 1.26 for NE, and 1.33 +/- 0.87 for DA. These values were based on the pooled analyses of five individual fish taken over seven different sampling periods. The E:NE ratio in resting fish was always less than 1.0. In a second experiment, fish were subjected to dorsal aorta cannulation and sequential blood samples were taken immediately after surgery, and 6, 24, and 48 hr later. Plasma E concentrations were 36 times greater than baseline values in the first sample; NE was 15 times greater and DA was 41 times greater. After surgery, plasma concentrations of all CAs fell rapidly but values were still higher than baseline 6 hr after surgery, then were near baseline at 24 and 48 hr after surgery. The E:NE ratio was about 3.0 immediately after surgery, dropped to 1.8 at 6 hr, and was about 1.0 at 24 and 48 hr. In a third experiment, plasma CAs were determined in a group of five animals anesthetized with tricaine methanesulfonate (100 mg/ml) to advanced anesthesia, and then allowed to recover in flowing well water over a 12-hr observation period. Plasma E and NE concentrations in the fish during early anesthesia (1.14 +/- 0.14 min) were not significantly different from preanesthesia values.(ABSTRACT TRUNCATED AT 250 WORDS)

Policy makers and administrators have become frustrated with single-subject designs because these designs appear unable, at first blush, to provide them with essential information that they can use in planning or change at the organizational or institutional level of management. Practitioners have become frustrated with prior exclusive reliance on traditional group experimental designs because they fail to provide useful information for conducting therapy or delivering services. The following article by Professor Gingerich makes a large and important contribution toward mitigating these two apparently divergent needs. Gingerich describes how meta-analysis can provide useful information for managers through aggregations of data obtained from single-subject, time-series designs. The article also discusses the use of meta-analysis of time-series data as a basis for improving the quality of scientific investigations.

1. Total blood volume and relative blood volumes in selected tissues were determined in non-anesthetized, confined rainbow trout by using 51Cr-labelled trout erythrocytes as a vascular space marker. 2. Mean total blood volume was estimated to be 4.09 +/- 0.55 ml/100 g, or about 75% of that estimated with the commonly used plasma space marker Evans blue dye. 3. Relative tissue blood volumes were greatest in highly perfused tissues such as kidney, gills, brain and liver and least in mosaic muscle. 4. Estimates of tissue vascular spaces, made using radiolabelled erythrocytes, were only 25-50% of those based on plasma space markers. 5. The consistently smaller vascular volumes obtained with labelled erythrocytes could be explained by assuming that commonly used plasma space markers diffuse from the vascular compartment.

A step-by-step procedure is needed for evaluating social work practice. This article describes such a procedure, with particular emphasis placed on practical concerns that arise in the use of evaluation techniques, and shows that clinical evaluation is compatible and consistent with most problem-solving models already in use by experienced practitioners.

This article describes the form of brief therapy developed at the Brief Family Therapy Center. We have chosen a title similar to Weakland, Fisch, Watzlawick, and Bodin's classic paper, "Brief Therapy: Focused Problem Resolution" (20) to emphasize our view that there is a conceptual relationship and a developmental connection between the points of view expressed in the two papers.