Solid-state selective (13)C excitation and spin diffusion NMR to resolve spatial dimensions in plant cell walls

The average spatial dimensions between major biopolymers within the plant cell wall can be resolved using a solid-state NMR technique referred to as a (13)C cross-polarization (CP) SELDOM (selectively by destruction of magnetization) with a mixing time delay for spin diffusion. Selective excitation of specific aromatic lignin carbons indicates that lignin is in close proximity to hemicellulose followed by amorphous and finally crystalline cellulose. (13)C spin diffusion time constants (T(SD)) were extracted using a two-site spin diffusion theory developed for (13)C nuclei under magic angle spinning (MAS) conditions. These time constants were then used to calculate an average lower-limit spin diffusion length between chemical groups within the plant cell wall. The results on untreated (13)C enriched corn stover stem reveal that the lignin carbons are, on average, located at distances ～0.7-2.0 nm from the carbons in hemicellulose and cellulose, whereas the pretreated material had larger separations.     

Comparison of Insulin Sensitivity of Horses Adapted to Different Exercise Intensities

Diets high in concentrates and soluble carbohydrates are associated with reduced insulin sensitivity in horses. Exercise training could protect against diet-induced insulin resistance. The objective of this study was to determine the intensity of exercise training required to affect insulin sensitivity in stabled horses fed a diet high in concentrates but moderate in soluble carbohydrates. In all, 31 stabled horses underwent three different exercise regimens: turnout, light exercise, and moderate exercise, while being fed a diet containing 60% concentrate. Blood was sampled monthly and analyzed for insulin. Insulin sensitivity was assessed using basal insulin concentrations and calculated insulin sensitivity (reciprocal of the square root of insulin) and compared across months by analysis of variance with repeated measures. Insulin sensitivity (reciprocal of the square root of insulin) was higher during periods of moderate and light physical activity as compared with turnout. These results indicate that turnout alone may not be adequate to improve insulin sensitivity in horses fed high amounts of concentrate.     

Leishmania spp. in Didelphis albiventris and Micoureus paraguayanus (Didelphimorphia: Didelphidae) of Brazil

Leishmaniasis is kept in nature by the participation of several animal species. This study evaluated the presence of Leishmania spp. in skin samples of free-ranging marsupials Micoureus paraguayanus (n=95) and Didelphis albiventris (n=191), captured in Morro do Diabo State Park and in sections of its surrounding forest, in the region of Pontal do Paranapanema, S?o Paulo State, Brazil. The samples were tested for the presence of kDNA of Leishmania spp. by polymerase chain reaction (PCR) and by real time PCR (qPCR). All samples from D. albiventris tested by PCR were negative for the presence of kDNA of Leishmania spp. However, when tested by qPCR, the positivity was 1.6%. A positivity of 7.4% by PCR and 11.6% by qPCR was observed for M. paraguayanus. Sixty-four per cent (9/14) of positive animals were limited to the same forest fragment. Presence of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis was detected in M. paraguayanus samples. While D. albiventris is the most studied marsupial species due to its urban habits, other marsupial species such as M. paraguayanus can be potential reservoirs of Leishmania spp. and should also be studied.     

Neoplastic melanocytic pleural effusion in a Portuguese water dog

A 9-year-old castrated male Portuguese water dog was presented following incomplete excision of a malignant melanoma at the left lip commissure by the referring veterinarian. Physical examination was otherwise unremarkable. The patient was staged using thoracic radiographs, abdominal ultrasound, and fine-needle aspirates of the mandibular lymph nodes and spleen. Given the absence of any definitive evidence of metastasis, the malignant melanoma was surgically completely removed. The dog then received four melanoma vaccine doses as an adjuvant therapy and remained clinically healthy for more than 3 months after the last immunization. However, 232 days after the initial discovery of the lip mass, the dog was euthanized due to deterioration and a poor prognosis based on the presence of lung metastases and neoplastic melanocytic pleural effusion. The latter has been rarely reported in dogs, despite the high prevalence of oral malignant melanomas and the tendency of these tumors to metastasize to the lungs.     

Can scale-dependent landcover relationships explain canid community composition independent of intraguild occupancy?

Landscape Ecology - Niche theory is frequently used as a framework to integrate environmental variables and species interactions to describe species geographic distribution. Yet, the scale at which...     

Left atrial rupture in dogs: 14 cases (1990–2005)

Objective: To describe the clinical parameters, treatment, and prognosis of dogs with left atrial rupture secondary to chronic mitral valve insufficiency. Design: Retrospective study. Setting: University referral hospital. Animals: 14 dogs with left atrial rupture. Interventions: None. Measurements and main results: Mixed breed dogs (n=6, 43%) and Shetland Sheepdogs (n=3, 21%) were most commonly affected. The median age was 12 years (range 5.8–18 y). The median weight was 11 kg (range 4–30 kg). Eight dogs had been previously diagnosed with chronic valvular disease. The most common presenting complaints included collapse (13/14), cough (9/14), and dyspnea (8/14). Four dogs were presented in either respiratory or cardiac arrest. Pericardial effusion was present in 13 dogs. The median left atrium:aortic outflow ratio was 2.66 (range 1.66:1–5.52:1). Pericardiocentesis was performed to alleviate tamponade in 3 dogs. Five dogs were discharged from the hospital, 3 of which were euthanized within 35 days of initial diagnosis for recurrence of clinical signs (n=2) and for hematochezia and lethargy (n=1). Five dogs were euthanized while in the hospital for a variety of reasons including DIC, progressive azotemia, collapse and recurrence of pericardial effusion, or possible seizure episode. Conclusions: Although rare, left atrial rupture resulting in pericardial effusion should be considered in older small‐ to medium‐sized dogs presenting with collapse, cough, and dyspnea. The overall prognosis appears poor.