Uptake and translocation of benomyl and carbendazim (methyl benzimidazol-2-yl carbamate) in the symplast

Cytoplasmic uptake of carbendazim (methyl benzimidazol-2-yl carbamate; MBC) from an aqueous solution was demonstrated with isolated mesophyll cells. About 2.5% of the labelled MBC (ring-2-[¹⁴C]) in the treatment solution (1.85 μg/ml) was taken up in 44 h. When cotyledons of cucumber seedling were treated with either 347 or 36 μg [¹⁴C]-MBC/plant 1.11 and 0.13% were extracted, respectively, from the remainder of the plant, 5 days after treatment. Greatest amounts were detected in shoot apices. Likewise, when MBC and benomyl were applied at the dose of 2 μmol, 0.34 and 0.57% were detected in the untreated part of the plant with a bioassay procedure. Foliar application with 347 or 36 μg[¹⁴C]-MBC/leaf resulted in the translocation of 1.68 and 0.11% out of the treated area. By scalding the living cells of the petiole translocation was prevented suggesting that long distance movement occurred in the symplast. During a period of 14 days 1.56% of [¹⁴C]-MBC applied to cucumber leaves was metabolised and respired as CO₂. This degradation was assumed to occur enzymically within the symplast.     

Use of biphasic electrical cardioversion for treatment of idiopathic atrial fibrillation in two horses

Rectilinear biphasic cardioversion was used in 2 horses with idiopathic sustained atrial fibrillation; 1 horse converted to sustained sinus rhythm. Variables that potentially affected outcome of the electrical cardioversion procedures in these horses included duration of arrhythmia, placement of cardioverter pads and paddles, serum electrolyte concentrations, and treatment with quinidine. Serum cardiac troponin I concentration, measured to determine whether the myocardium was damaged from the electrical shocks, was within the reference range in both horses after the procedure. Biphasic electrical cardioversion may provide an alternative to pharmacologic cardioversion with quinidine in horses. The rectilinear biphasic defibrillator-cardioverter uses a unique biphasic waveform to deliver constant current to the myocardium during cardioversion, regardless of transthoracic impedance. Biphasic cardioversion is safer and more effective than traditional monophasic cardioversion in humans and animals.     

A pilot study examining a proprietary herbal blend for the treatment of canine osteoarthritis pain

Osteoarthritis is the most common joint disease in dogs. Despite the use of nonsteroidal anti-inflammatory drugs (NSAIDs), many owners seek natural therapies; either to augment the response to NSAIDs, or as a replacement. Substantial research has been directed to investigation of novel therapies. A randomized, double-blinded, controlled study was conducted to assess the efficacy of a herbal remedy for treatment of canine osteoarthritis pain. Client-owned dogs (N = 24) with osteoarthritis were enrolled between 2 veterinary hospitals. Each dog underwent veterinary and owner assessment at 0, 4, and 8 weeks, using the Canine Brief Pain Inventory and Hudson activity scale. Blood was collected for a complete blood (cell) count (CBC) and serum chemistry analysis. The product was deemed to be safe and well-tolerated at the manufacturer recommended dosage, with no significant changes seen in the CBC or serum biochemical analyses. Aside from1 dog that developed gastrointestinal upset, all other dogs tolerated the supplement without complication. The supplement did not statistically improve clinical signs in dogs based on veterinary or owner assessments of lameness. There was a treatment/time effect when assessing veterinary pain scores; however, post-hoc analysis suggests no observable benefit of treatment compared with the placebo group at any time point.     

Report of the American Animal Hospital Association (AAHA) Canine Vaccine Task Force: executive summary and 2003 canine vaccine guidelines and recommendations

The AAHA has undertaken the development of this document in an effort to inform veterinary practitioners, clarify misunderstandings held by veterinarians, and encourage practitioners to recognize that immunization of patients is a medical procedure. As such, it is bound by the same tenets that govern the recommendation of other medical procedures-principally, that it be tailored to the needs of the individual patient. Many diseases we immunize against are ubiquitous. Many are serious and some even life threatening. Some are of limited demographic concern given the exposure risk for each patient. These factors have all been considered in developing the AAHA Canine Vaccination Guidelines. In the end, each veterinarian must do what he or she determines to be in the best interest of the patient. Vaccination of individual animals produces not only individual immunity but also population or herd immunity. Since we have no readily available and reliable way to determine if each patient has developed an adequate immune response, we encourage the practice philosophy of vaccinating more patients while vaccinating each patient no more than needed.     

Transcatheter intravascular stent placement to relieve supravalvular pulmonic stenosis

Valvular pulmonic stenosis has been successfully treated in dogs via minimally invasive transcatheter balloon dilation procedures for almost 20 years. Supravalvular pulmonic stenosis however is not amenable to balloon dilation procedures. Although several surgical procedures are described for treatment of pulmonic stenosis, the morbidity and mortality of these procedures are significantly higher than for transcatheter approaches.Two cases of supravalvular pulmonic stenosis are presented, one acquired and one congenital, which were successfully treated with transcatheter intravascular stent placement. The procedure alleviated the stenotic lesion and resolved clinical signs.     

Effect of temperature on the starch content of potato callus tissue

Starch content was determined in Lemhi Russet callus grown on MS medium for 2 and 4 weeks at 25, 15, and 5°C with 50 μM 2,4-D or 10 μM picloram as the only plant growth regulator. A treatment of 5°C for 4 weeks followed by 25°C for 2 and 4 weeks was included to simulate reconditioning. Callus starch content ranged from 0.01 to 0.08% on a wet weight basis and 0.5 to 4.0% on a dry weight basis. Starch content was highest after 2 weeks at 25 and 15°C and decreased with time in a similar manner at both 25 and 15°C. Starch content decreased at 5°C, then increased significantly during simulated reconditioning at 25°C. Starch content was higher in callus grown with 50 μM 2,4-D than in callus grown with 10 μM picloram. After staining the callus with I₂-KI solution, starch granule formation was observed in the callus grown with 50 μM 2,4-D, while little granule formation was observed in the callus grown with 10 μM picloram.     

Fruit and vegetable availability: a micro environmental mediating variable?

OBJECTIVES: To examine the association between fruit and vegetable (F&V) availability and consumption, the possible influences on this association, research gaps, and implications for developing strategies to increase F&V consumption. DESIGN: Systematic review of studies that have examined associations between F&V availability and consumption. RESULTS: Qualitative studies conducted among children and adults indicated that greater availability was associated with greater consumption. This finding was supported by cross-sectional studies among children. Availability was associated with dietary psychosocial variables such as preferences, and it appears that availability may moderate the relationship between these psychosocial variables and consumption. Intervention studies attempting to increase availability have resulted in increased consumption, and availability has predicted change in consumption over an 18-month period. DISCUSSION: Availability appears to be a key proximal determinant of consumption, especially of F&V, and thereby provides a target for change. However, the mechanisms that relate these variables are unclear and there is a need to clarify the direction of causality. We suggest that the possible causal mechanisms may include: (1) availability simply facilitates increased consumption; (2) the visual cues of available food may stimulate consumption; and (3) available food exposure may increase preference, which leads to increased consumption. Each of these possibilities requires close examination, as do policy-level interventions. CONCLUSION: F&V availability is associated with increased consumption. Research that elucidates the mechanisms between availability and intake, and tests policy-level interventions, is needed to advance increased availability as a public health procedure.     

Diagnosis and management of thyroid disorders and thyroid hormone supplementation in adult horses and foals

Equine thyroid disorders pose a diagnostic challenge in clinical practice because of the effects of nonthyroidal factors on the hypothalamic–pituitary–thyroid axis, and the horse's ability to tolerate wide fluctuations in thyroid hormone concentrations and survive without a thyroid gland. While benign thyroid tumours are common in older horses, other disorders like primary hypothyroidism or hyperthyroidism in adult horses and congenital hypothyroidism in foals are rare. There is a common misunderstanding regarding hypothyroidism in adult horses, especially when associated with the clinical profile of obesity, lethargy, and poor performance observed in dogs and humans. Low blood thyroid hormone concentrations are often detected in horses as a secondary response to metabolic and disease states, including with the nonthyroidal illness syndrome; however, it is important to note that low thyroid hormone concentrations in these cases do not necessarily indicate hypothyroidism. Assessing equine thyroid function involves measuring thyroid hormone concentrations, including total and free fractions of thyroxine (T4) and triiodothyronine (T3); however, interpreting these results can be challenging due to the pulsatile secretion of thyroid hormones and the many factors that can affect their concentrations. Dynamic testing, such as the thyrotropin-releasing hormone stimulation test, can help assess the thyroid gland response to stimulation. Although true hypothyroidism is extremely rare, thyroid hormone supplementation is commonly used in equine practice to help manage obesity and poor performance. This review focuses on thyroid gland pathophysiology in adult horses and foals, interpretation of blood thyroid hormone concentrations, and evaluation of horses with thyroid disorders. It also discusses the use of T4 supplementation in equine practice.     

Laboratory and on-farm studies on the bioaccumulation and elimination of dioxins from a contaminated mineral supplement fed to dairy cows

A dioxin-contaminated mineral supplement was used to study the bioaccumulation and elimination of dioxins in two dairy cows. The supplement was mixed into the total maintenance ration and fed to the cows for 40 days after which unfortified diets were fed for 40 additional days. Dioxins and coplanar polychlorinated biphenyls (PCBs) were measured twice a week in the milk and in selected tissues of the cows, one at death (day 10 of withdrawal) and one at slaughter (day 40 of withdrawal). The dioxins and PCBs were readily transferred into the milk, and at steady state, total toxic equivalents were concentrated 6-fold into the milk fat from the diet. Bioaccumulation was inversely related to chlorination number. The elimination of dioxins and PCBs in milk was biphasic. With the exception of 1,2,3,4,6,7,8-heptachlorodioxin and both octachlorinated congeners, dioxin and furan half-lives in milk were approximately 3-5 days for the alpha-phase and 35-50 days for the beta-phase. PCB-169 had a longer half-life: 11 (alpha) and 200 days (beta). When milk and feed samples from Minnesota farms that had used similar contaminated mineral supplements were analyzed, no elevated dioxin levels were found in milk. It appeared that although the dioxins from the mineral supplements have the potential to bioaccumulate, dilution into the total diet was sufficient to prevent a significant rise in the dioxin concentrations in the milk at these farms.