At the end of 2019, a novel coronavirus (severe acute respiratory syndrome coronavirus 2; SARS-CoV-2) was detected in Wuhan, China, that spread rapidly around the world, with severe consequences for ...human health and the global economy. Here, we assessed the replicative ability and pathogenesis of SARS-CoV-2 isolates in Syrian hamsters. SARS-CoV-2 isolates replicated efficiently in the lungs of hamsters, causing severe pathological lung lesions following intranasal infection. In addition, microcomputed tomographic imaging revealed severe lung injury that shared characteristics with SARS-CoV-2−infected human lung, including severe, bilateral, peripherally distributed, multilobular ground glass opacity, and regions of lung consolidation. SARS-CoV-2−infected hamsters mounted neutralizing antibody responses and were protected against subsequent rechallenge with SARS-CoV-2. Moreover, passive transfer of convalescent serum to naïve hamsters efficiently suppressed the replication of the virus in the lungs even when the serum was administrated 2 d postinfection of the serum-treated hamsters. Collectively, these findings demonstrate that this Syrian hamster model will be useful for understanding SARS-CoV-2 pathogenesis and testing vaccines and antiviral drugs.
Anesthesia Case of the Month Bartholomew, Kyle J; Loeber, Samantha J; Johnson, Rebecca A
Journal of the American Veterinary Medical Association,
03/2022, Letnik:
260, Številka:
12
Journal Article
Abstract Objective To describe the technique for anastomosis of the caudal thoracic duct (TD) to the 10th or 11th intercostal vein (ICV) using a microvascular anastomotic coupler (MAC) device in dogs ...and assess patency of the anastomosis on days 0 and 30. Study design Experimental study. Sample population Six adult Beagle dogs. Methods Under general anesthesia, fluoroscopic popliteal lymphangiography was performed and the TD identified. A right ninth or 10th intercostal thoracotomy was performed. Using an operating microscope, the TD and the 10th or 11th ICV were isolated, ligated, and anastomosed using a 1.5 or 2.0 mm MAC. Fluoroscopic popliteal lymphangiography was repeated immediately after surgery and on day 30. Results The anastomosis was successful and lymphangiography documented flow into the azygos vein in all six dogs immediately after surgery. At day 30, the anastomosis was patent in four of six dogs. In two dogs, flow through the anastomosis was obstructed due to kinking of the ICV just cranial to the MAC. Conclusion Anastomosis of the TD and ICV using a MAC was feasible and was shown to maintain patency up to 30 days. When performing the anastomosis, care should be taken to ensure the ICV is not kinked by the MAC. Clinical significance Direct anastomosis of the TD and ICV may have application for treatment of idiopathic chylothorax in dogs by maintaining flow from the abdominal lymphatics to the central venous circulation and thereby preventing the stimulus for collateral circulation and persistent chylous effusion. Further investigation is warranted to assess the efficacy of this technique in dogs affected with idiopathic chylothorax.
Tarsal joint abnormalities have been observed in aged male mice on a C57BL background. This joint disease consists of calcaneal displacement, inflammation, and proliferation of cartilage and ...connective tissue, that can progress to ankylosis of the joint. While tarsal pathology has been described previously in C57BL/6N substrains, as well as in STR/ort and B10.BR strain, no current literature describes this disease occurring in C57BL/6J mice. More importantly the behavioral features that may result from such a change to the joint have yet to be evaluated. This condition was observed in older male mice of the C57BL/6J lineage, around the age of 20 weeks or older, at a frequency of 1% of the population. To assess potential phenotypic sequela, this study sought to evaluate body weight, frailty assessment, home cage wheel running, dynamic weight bearing, and mechanical allodynia with and without the presence of pain relief with morphine. Overall mice with tarsal injuries had significantly higher frailty scores (p< 0.05) and weighed less (p<0.01) compared to unaffected mice. Affected mice had greater overall touch sensitivity (p<0.05) and they placed more weight on their forelimbs (p<0.01) compared to their hind limbs. Lastly, when housed with a running wheel, affected mice ran for a shorter length of time (p<0.01) but tended to run a greater distance within the time they did run (p<0.01) compared to unaffected mice. When tested just after being given morphine, the affected mice performed more similarly to unaffected mice, suggesting there is a pain sensation to this disease process. This highlights the importance of further characterizing inbred mouse mutations, as they may impact research programs or specific study goals.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This retrospective study aimed to measure rabbit laryngotracheal dimensions at different locations on computed tomography (CT), assess the relationship of these measurements with rabbit body weight, ...determine the most common narrowest measurement and assess its relationship with endotracheal tube (ETT) size and body weight.
66 adult domestic rabbits (Oryctolagus cuniculus) of different breeds and body weights.
CT laryngotracheal luminal height, width, and cross-sectional area measurements were made at the rostral thyroid cartilage at the level of the arytenoids, caudal thyroid cartilage/rostral cricoid cartilage, caudal cricoid cartilage/cranial trachea, and trachea at the level of the fifth cervical vertebra.
The data for every measurement of luminal airway dimensions revealed robust positive associations with body weight (P < .001). The narrowest laryngotracheal measurement was the width at the level of the caudal thyroid cartilage/rostral cricoid cartilage, and the smallest cross-sectional area was at the rostral thyroid cartilage at the level of the arytenoids. There was a strong association between body weight and the likelihood of appropriate ETT fit. To have at least an 80% chance of appropriate ETT fit with a 2.0, 2.5, and 3.0 mm ETT, the rabbits' weight predicted by the model (lower 95% confidence limit) were at least 2.99 (2.72) kg, 5.24 (4.65) kg, and 5.80 (5.21) kg, respectively.
The laryngotracheal lumen was narrowest at the level of the caudal thyroid cartilage in rabbits, which indicates this location may be the limiting factor in determining ETT size in rabbits.
Objective
To describe a technique for anastomosis of the thoracic duct (TD) to the 11th or 12th intercostal vein (ICV) using a microvascular anastomotic coupler (MAC) in the dog.
Study design
...Cadaveric study.
Animals
Eight beagles.
Methods
A right paracostal laparotomy and 10th intercostal thoracotomy were performed in each dog. Mesenteric contrast lymphography was used to identify the TD and its branches on fluoroscopy. The TD and adjacent 11th or 12th ICV were isolated, double ligated, and divided using a surgical microscope. The caudal TD and proximal ICV were anastomosed in an end‐to‐end fashion using a 1.5 mm or 2 mm MAC. Mesenteric lymphography was repeated to document patency of the anastomosis.
Results
The TD was identified via lymphography in all dogs; five dogs had a single duct, and three dogs had additional branches. The anastomosis was successful in all eight dogs, and flow into the azygos vein without leakage was confirmed via lymphography.
Conclusion
End‐to‐end anastomosis of the TD to an ICV using a MAC was technically feasible in the canine cadaver.
Clinical significance
Lymphaticovenous anastomosis combined with TD ligation may have application as a treatment for idiopathic chylothorax. By maintaining the flow of chyle from the abdominal lymphatics to the systemic circulation, this procedure may reduce the stimulus for collateral circulation and persistent flow to the cranial mediastinal lymphatics.
A 2‐year‐old male neutered Rat Terrier was presented for alopecia, recurrent urinary tract infections, and urinary incontinence. Abdominal ultrasound and CT identified a thin, tubular, paired ...structure arising from the craniodorsal aspect of an enlarged, cystic prostate. An atypical uterus masculinus was initially suspected, however it was then identified that the patient had chronic exogenous estrogen exposure, and surgical resection and histopathology was consistent with an enlarged and inflamed vas deferens. Vas deferens enlargement and vasitis secondary to chronic hyperestrogenism should be considered for a tubular, paired structure arising from the craniodorsal prostate in a male dog.
A 14-week-old male unilaterally cryptorchid Clumber spaniel was presented for acute lethargy. Physical examination revealed abdominal pain, and a single testis was palpated in the scrotum. Abdominal ...ultrasound and computed tomography (CT) revealed a poorly vascularized, ovoid structure immediately caudal to the left kidney with scant regional peritoneal effusion. Left intra-abdominal testicular torsion was confirmed at surgery, and routine cryptorchidectomy was performed. The patient recovered uneventfully from anesthesia and surgery. Key clinical message: The most common CT characteristics of testicular torsion were present in this case and correlated well with sonographic findings to allow for rapid, accurate diagnosis and surgical planning of unilateral, non-neoplastic, intra-abdominal cryptorchid testicular torsion in a juvenile dog. Contrast enhanced CT facilitated accurate localization of the undescended testis and evaluation of testicular perfusion and may be a useful alternative to ultrasound for diagnosing testicular torsion, especially in indeterminate cases.
During the current coronavirus disease 2019 (COVID-19) pandemic, a variety of mutations have accumulated in the viral genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and, at ...the time of writing, four variants of concern are considered to be potentially hazardous to human society
. The recently emerged B.1.617.2/Delta variant of concern is closely associated with the COVID-19 surge that occurred in India in the spring of 2021 (ref.
). However, the virological properties of B.1.617.2/Delta remain unclear. Here we show that the B.1.617.2/Delta variant is highly fusogenic and notably more pathogenic than prototypic SARS-CoV-2 in infected hamsters. The P681R mutation in the spike protein, which is highly conserved in this lineage, facilitates cleavage of the spike protein and enhances viral fusogenicity. Moreover, we demonstrate that the P681R-bearing virus exhibits higher pathogenicity compared with its parental virus. Our data suggest that the P681R mutation is a hallmark of the virological phenotype of the B.1.617.2/Delta variant and is associated with enhanced pathogenicity.
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