Laryngeal paralysis secondary to cervical bite injuries in five dogs.

CASE HISTORIES: Medical records of a veterinary hospital in Belgium were reviewed for dogs (n = 5) that presented between 2016 and 2019 with laryngeal paralysis secondary to bite wounds to the cervical region received while fighting with other dogs. The time elapsed between the trauma and presentation was from a few hours up to 5 days. CLINICAL FINDINGS AND TREATMENT: Bilateral laryngeal paralysis was identified in three dogs and unilateral laryngeal paralysis in two dogs via endoscopic assessment of laryngeal function. The primary concomitant lesions included tracheal injury in 3/5 dogs and oesophageal injury in 1/5 dogs. One dog with bilateral laryngeal paralysis was treated medically as no signs of dyspnoea were present. Surgical management was elected in 4/5 dogs based on evaluation of their clinical status and lesions revealed by endoscopic examination of upper gastrointestinal and respiratory tracts. Dogs underwent surgical procedures that were determined to be appropriate for treatment of the lesions identified on clinical examination, diagnostic imaging, and endoscopy. The cervical region was explored through a ventral midline approach in 2/4 cases, to close tracheal perforations. Temporary tracheostomy was performed in 2/4 cases. Procedures to correct brachycephalic airway obstructive syndrome were performed in 2/4 cases. Cricoarytenoid lateralisation was performed in 2/4 dogs. Dogs were hospitalised for 2-10 days and received antimicrobial therapy before surgery and for 2-3 weeks after surgery. Physical examination and respiratory function were normal in 3/5 dogs 4-6 months after discharge. Information regarding outcomes for two cases was obtained from the owners by telephone assessment 1-6 months after surgery. The owner of each dog reported the respiratory function to be excellent. DIAGNOSIS: Uni- or bilateral, transient or permanent laryngeal paralysis with concomitant oesophageal, tracheal, or laryngeal lesions following cervical dog bite injuries diagnosed by endoscopic examination of upper gastrointestinal and respiratory tracts. CLINICAL RELEVANCE: This case series describes the diagnosis and management of dogs with laryngeal paralysis secondary to cervical dog bite injuries. To the authors' knowledge, this is the first published report documenting bilateral laryngeal paralysis secondary to cervical dog bite injuries. Clinicians should be aware of this pathology and the importance of investigating laryngeal function in dogs presenting with cervical bites, particularly those with inspiratory dyspnoea. Upper airway and digestive endoscopy are recommended for complete assessment of cervical traumatic injuries.

Pulmonary Vein-to-Pulmonary Artery Ratio is an Echocardiographic Index of Congestive Heart Failure in Dogs with Degenerative Mitral Valve Disease.

BACKGROUND: Early recognition of left-sided congestive heart failure (CHF) in dogs with degenerative mitral valve disease (DMVD) is important because it influences medical therapy, timing of follow-up, and outcome. HYPOTHESIS: Pulmonary vein diameter-to-pulmonary artery diameter ratio (PV/PA) measured by echocardiography can predict CHF. ANIMALS: Ninety-eight client-owned dogs, 37 controls, and 61 dogs with DMVD. METHODS: Prospective clinical cohort study. History, physical examination and Doppler-echocardiography were performed. Dogs were classified as International Small Animal Cardiac Health Council class I, II or III. Congestive heart failure was identified in a subset of 56 dogs based on radiographic findings. The PV/PA was measured in bidimensional (2D) and M-mode by 2 investigators blinded to the radiologists' conclusions. RESULTS: Interobserver coefficients of variation for PV/PA acquisition and measurement were <10%. The PV/PA in control dogs was approximately 1 and increased with class of heart failure. The presence of CHF could be best predicted by measuring PV/PA in 2D echocardiography (cut-off, 1.7; area under the curve, 0.98; CI, 0.97-0.98; P < .001) with a sensitivity of 96% and a specificity of 91%. CONCLUSION AND CLINICAL IMPORTANCE: The PV/PA is a simple and reproducible echocardiographic variable that increases with class of heart failure and may help discriminate dogs in CHF from asymptomatic dogs with DMVD. Additional studies are required to determine whether PV/PA might provide additional information in the integrated interpretation of Doppler-echocardiographic indices of left ventricular filling pressures and could be used for rapid assessment of CHF in dogs in a critical care setting.

Ultrasonographic percutaneous anatomy of the atlanto-occipital region and indirect ultrasound-guided cisternal puncture in the dog and the cat.

Cisternal puncture in dogs and cats is commonly carried out. This article describes the percutaneous ultrasound anatomy of the cisternal region in the dog and the cat and an indirect technique for ultrasound-guided cisternal puncture. Ultrasound images obtained ex vivo and in vivo were compared with anatomic sections and used to identify the landmarks for ultrasound-guided cisternal puncture. The ultrasound-guided procedure was established in cadavers and then applied in vivo in seven dogs and two cats. The anatomic landmarks for the ultrasound-guided puncture are the cisterna magna, the spinal cord, the two occipital condyles on transverse images, the external occipital crest and the dorsal arch of the first cervical vertebra on longitudinal images. Using these ultrasound anatomic landmarks, an indirect ultrasound-guided technique for cisternal puncture is applicable in the dog and the cat.

Bioavailable nitrate detection in water by an immobilized luminescent cyanobacterial reporter strain.

Cyanobacteria are a major group of photosynthetic bacteria that can accumulate in surface water as so-called "blooms" in response to environmental factors such as temperature, light and certain nutrients such as N, P, and Fe. Some species of cyanobacteria produce toxins, causing a considerable danger for human and livestock health. As a consequence, monitoring of bloom formation and toxin production of drinking water supplies has become a major concern. To enable prediction and monitoring of cyanobacterial blooms, tools to detect nutrient bioavailability in water would be advantageous. A whole-cell biosensor was developed for monitoring nitrate (NO(3-)) bioavailability in aquatic ecosystems using the recombinant bioluminescent cyanobacterial strain Synechocystis PCC 6803 harboring an insertion of a luxAB-kmr fusion with nblA1 in its chromosomal DNA, leading to PnblA::luxAB-kmr. This reporter strain was designated N1LuxKm. Cells were immobilized in microtiter plates and showed a dose-dependent response to nitrate deprivation. The resultant CyanoSensor could detect nitrate in the 4-100 micro M concentration range after a sample incubation time of 10 h under continuous illumination (50 micro E m(-2) s(-1)). The optimal temperature for sensor operation was 29 degrees C and the immobilized biosensor could be stored at 4 degrees C in dark for about 1 month without significant loss of sensitivity.

In diatoms, a transthylakoid proton gradient alone is not sufficient to induce a non-photochemical fluorescence quenching.

Non-photochemical fluorescence quenching (NPQ) in diatoms is associated with a xanthophyll cycle involving diadinoxanthin (DD) and its de-epoxidized form, diatoxanthin (DT). In higher plants, an obligatory role of de-epoxidized xanthophylls in NPQ remains controversial and the presence of a transthylakoid proton gradient (DeltapH) alone may induce NPQ. We used inhibitors to alter the amplitude of DeltapH and/or DD de-epoxidation, and coupled NPQ. No DeltapH-dependent quenching was detected in the absence of DT. In diatoms, both DeltapH and DT are required for NPQ. The binding of DT to protonated antenna sites could be obligatory for energy dissipation.

DeltapH-dependent photosystem II fluorescence quenching induced by saturating, multiturnover pulses in red algae

We have previously shown that in the red alga Rhodella violacea, exposure to continuous low intensities of light 2 (green light) or near-saturating intensities of white light induces a DeltapH-dependent PSII fluorescence quenching. In this article we further characterize this fluorescence quenching by using white, saturating, multiturnover pulses. Even though the pulses are necessary to induce the DeltapH and the quenching, the development of the latter occurred in darkness and required several tens of seconds. In darkness or in the light in the presence of 2, 5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, the dissipation of the quenching was very slow (more than 15 min) due to a low consumption of the DeltapH, which corresponds to an inactive ATP synthase. In contrast, under far-red illumination or in the presence of 3-(3,4-dichlorophenyl)-1,1'-dimethylurea (only in light), the fluorescence quenching relaxed in a few seconds. The presence of N, N'-dicyclohexyl carbodiimide hindered this relaxation. We propose that the quenching relaxation is related to the consumption of DeltapH by ATP synthase, which remains active under conditions favoring pseudolinear and cyclic electron transfer.