Limb Specific Failure of Proliferation and Translation in the Mesenchyme Leads to Skeletal Defects in Diamond Blackfan Anemia

Ribosomopathies are a class of disorders caused by defects in the structure or function of the ribosome and characterized by tissue-specific abnormalities. Diamond Blackfan anemia (DBA) arises from different mutations, predominantly in genes encoding ribosomal proteins (RPs). Apart from the anemia, skeletal defects are among the most common anomalies observed in patients with DBA, but they are virtually restricted to radial ray and other upper limb defects. What leads to these site-specific skeletal defects in DBA remains a mystery. Using a novel mouse model for RP haploinsufficiency, we observed specific, differential defects of the limbs. Using complementary in vitro and in vivo approaches, we demonstrate that reduced WNT signaling and subsequent increased β-catenin degradation in concert with increased expression of p53 contribute to mesenchymal lineage failure. We observed differential defects in the proliferation and differentiation of mesenchymal stem cells (MSCs) from the forelimb versus the hind limbs of the RP haploinsufficient mice that persisted after birth and were partially rescued by allelic reduction of Trp53. These defects are associated with a global decrease in protein translation in RP haploinsufficient MSCs, with the effect more pronounced in cells isolated from the forelimbs. Together these results demonstrate translational differences inherent to the MSC, explaining the site-specific skeletal defects observed in DBA.

Thermographic Screening of Beef Cattle Metatarsal Growth Plate Lesions

Lameness represents one of the main causes of decreased productive performance and impaired animal welfare in the bovine industry. Young beef bulls are predisposed to develop diseases of the growing skeleton, especially growth plate lesions. Early diagnosis is indispensable for ensuring correct treatment, fast recovery and reduction losses. However, when dealing with beef cattle, this is not always possible. Fast and reliable diagnostic imaging techniques are necessary to improve dealing with lameness in beef animals. The aim of the present study was to examine the potential of thermographic imaging as a non-invasive tool for rapidly screening beef bulls for the presence of growth plate lesions. Here, 20 Charolais and Limousine beef bulls affected by growth plate lesions in one of the rear limbs were selected. IRT was performed on both hind limbs using a digital infrared camera (ThermaCam T420 Model, Flir Systems, Boston, MA, USA), prior to radiographic imaging and clinical examination. The temperature of healthy and affected limbs was measured in two regions: the area correspondent to the growth plate (AR01) and the whole area of the metatarsus (AR02). Growth plate lesions were found to increase the maximum, mean, and minimum temperatures in AR01; and the mean and maximum temperatures in AR02, therefore, indicating the potential of IRT as a reliable, practical tool for screening growth plate lesions in beef bulls.

Strong differentiation between amphibian communities on two adjacent mountains in the Upper Rio Pastaza watershed of Ecuador, with descriptions of two new species of terrestrial frogs

We present the results of herpetological surveys in two adjacent mountains where the EcoMinga Foundation protects the cloud forest in the Upper Rio Pastaza watershed, in the Llanganates Sangay Ecological Corridor in Ecuador. A rapid assessment of the amphibian communities of the study sites reveals a diverse and heterogeneous composition, dominated by terrestrial frogs from the genus Pristimantis. We also identify a cryptic diversity with a significant number of candidate new species. We describe two new species of terrestrial frogs of the genus Pristimantis. Pristimantis maryanneaesp. nov. is characterised by not having tympanum externally visible and having 2–3 subconical tubercles in the upper eyelid; and Pristimantis burtoniorumsp. nov. is characterised by the presence of red colouration in hidden surfaces of the hind-limbs, tubercles on the upper eyelid, interorbital tubercle and a row of rounded tubercles along the snout to the tip and a pale red venter with dark brown mottled pattern. Our samples from the two Reserves do not share species between them, so the proportion of shared species seems to be relatively low. In addition, we highlight the importance of updating the knowledge of amphibians that are restricted to this important conservation region and comment about the threats and composition of the amphibian communities on the eastern slopes of the Upper Rio Pastaza watershed.

Tracking Radiolabeled Endothelial Microvesicles Predicts Their Therapeutic Efficacy: A Proof-of-Concept Study in Peripheral Ischemia Mouse Model Using SPECT/CT Imaging

Microvesicles, so-called endothelial large extracellular vesicles (LEVs), are of great interest as biological markers and cell-free biotherapies in cardiovascular and oncologic diseases. However, their therapeutic perspectives remain limited due to the lack of reliable data regarding their systemic biodistribution after intravenous administration. Methods: Applied to a mouse model of peripheral ischemia, radiolabeled endothelial LEVs were tracked and their in vivo whole-body distribution was quantified by microSPECT/CT imaging. Hindlimb perfusion was followed by LASER Doppler and motility impairment function was evaluated up to day 28 post-ischemia. Results: Early and specific homing of LEVs to ischemic hind limbs was quantified on the day of ischemia and positively correlated with reperfusion intensity at a later stage on day 28 after ischemia, associated with an improved motility function. Conclusions: This concept is a major asset for investigating the biodistribution of LEVs issued from other cell types, including cancer, thus partly contributing to better knowledge and understanding of their fate after injection.

A new species of the Gekko japonicus group (Squamata: Gekkonidae) from Khammouane Province, central Laos

A new species of the Gekko (Japonigekko) japonicus group from Khammouane Province, central Laos is described based on morphological characters and molecular evidence. Morphologically, Gekko khunkhamensis sp. nov. can be distinguished from the remaining congeners by a combination of the following characters: size moderate (SVL 69.7–75.2 mm); nares in contact with rostral; internasals absent; postmentals enlarged; interorbital scales between anterior corners of the eyes 31 or 32; dorsal tubercles absent; ventrals between mental and cloacal slit 181–185; midbody scales 127–138; ventral scales 42–45; subdigital lamellae on first toe 13 or 14, on fourth toe 14 or 15; tubercles on upper surface of fore and hind limbs absent; precloacal pores absent in the male and females; postcloacal tubercles 2; tubercles absent on dorsal surface of tail base; subcaudals distinctly enlarged; dorsal surface of body with five dark grey bands, which become irregular posteriorly. Genetically, the new species is placed in a clade, consisting of G. bonkowskii, G. nadenensis, G. scientiadventura, G. sengchanthavongi, and G. thakhekensis and differs from other congeners by at least 13% in terms of pairwise distance based on a fragment of the mitochondrial ND2 gene.

Traumatic exungulation in cattle: ten cases (1993–2018)

OBJECTIVE To describe clinical findings, treatments, and outcomes for cattle with complete traumatic exungulation. ANIMALS 10 bovines. PROCEDURES Record databases of 2 teaching hospitals were searched to identify cattle treated for traumatic exungulation between January 1993 and December 2018. Information about signalment, clinical signs and findings, treatment, and outcome was extracted from the records or obtained by telephone communication with the owner. RESULTS Records for 5 bulls, 4 heifers, and 1 cow with a median age of 2 years (range, 1 day to 10 years) and weight of 379.1 kg (range, 30 to 909.1 kg) were reviewed. Duration of clinical signs ranged from ≤ 24 hours to 3.5 days. Five of 7 animals had a lameness score > 3/5. Complete exungulation occurred in 6 medial digits (3 hind limbs and 3 forelimbs) and 5 lateral digits (1 hind limb and 4 forelimbs); 1 calf had complete exungulation of both digits of a forelimb. Treatments included bandaging (n = 9), antimicrobials (9), anti-inflammatories (8), hoof block application to the adjacent digit (7), regional anesthesia (6), cast application (4), curettage of the third phalanx (3), regional antimicrobial perfusion (1), and local application of antimicrobial-impregnated beads (1). All 7 cattle with long-term (≥ 9 months) information available returned to their intended function; 6 had no residual lameness, and 3 required regular corrective trimming of the affected digit. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested the prognosis for long-term survival and return to intended function is fair to good for cattle with complete exungulation.

Pathoanatomical findings of a green turtle (Chelonia mydas) victim of collision with a motorboat

In this paper we report the trauma suffered by a green turtle (Chelonia mydas), caused by a collision with a motorboat, and describe the case ante and post-mortem. An adult female green turtle was rescued alive on December 2, 2016 at Ponta Negra beach, municipality of Natal, Rio Grande do Norte, Brazil. The rescued animal was sent to the Marine Fauna Rehabilitation Center (PCCB-UERN), municipality of Areia Branca (RN), in Brazil. Physical examination revealed an excellent body score, noisy breathing, moderate dehydration, absence of hind limb and cloacal reflexes when stimulated by pressure, and two traumatic injuries characteristic of a collision with a motorboat. After three days of supportive treatment, the animal died and was immediately sent for necropsy. The animal had a complete fracture of the vertebral bodies (dorsal elements D9 and D10) and spinal cord section. The entire gastrointestinal tract had food content, in addition to sharp injuries in the colon caused by the bone fragments of the fractured carapace. The lungs were congested, hemorrhagic with frothy and bloody secretion, and interstitial bronchiole fibrosis. There was also present some fibrin and a large number of leukocyte cells, consisting mainly of macrophages. The liver was enlarged, with rounded edges and thickening of the capsule, multifocal areas of hepatocellular necrosis, and dissociation of the hepatocyte cords. The collision resulted in the exposure of the coelomic cavity and spinal cord, causing the animal intense pain, paralysis of the hind limbs and cloaca, septicemia, and consequently, death.

EFFECTS OF EXHAUSTIVE EXERCISE AND CONTUSION ON AUTOPHAGY-RELATED FACTORS IN SKELETAL MUSCLE OF RATS

ABSTRACT Objective: To study the effects of exhaustive exercise and contusion on autophagy-related factors Beclin1, LC3 and PINK1 expression in the skeletal muscle of rats. Methods: Forty-two male SD rats were randomly divided into 7 groups, 6 rats in each group: C, D0, D24, D48, E0, E24, and E48. Each group of rats was killed and dissected at the different respective time points specified above. The whole quadriceps femoris of the left hind limbs were removed and divided into two parts, one for mRNAs of Beclin1, LC3 and PINK1 by real-time fluorescent quantitative PCR, and the other for LC3 protein by Western blotting. Results: Compared with group C, the contents of Beclin1 mRNA, PINK1 mRNA, and LC3 mRNA in the immediate exhaustive exercise group (E0) were significantly reduced p<0.01. However, the levels of PINK1 mRNA, LC3 mRNA, and LC3 protein in skeletal muscle cells increased significantly in the 48 hours after exhaustion (E48) p<0.05, suggesting that cell autophagy had an increasing trend during the recovery period. Meanwhile, compared with the C group, the contents of Beclin1 mRNA, PINK1 mRNA, and LC3 mRNA in the immediate blunt contusion group (D0) increased significantly p<0.01 and were followed by a downward trend. Conclusion: Generally, there were differences between the blunt contusion and exhausted exercise models at each recovery phase. The gene expression of the autophagy-related factors was not high in the early exhaustive exercise recovery phase and subsequently followed an upward trend. But the above factors increased significantly in the immediate and early recovery phases after blunt contusion. Injury from blunt contusion may be more severe than exhaustive exercise-induced-injury, so the autophagy starts earlier according to the changes in autophagy-related factors. Level of evidence III; Therapeutic studies investigating the results of treatment.

Intrasound Therapy Improves the Mechanical Properties and the Morphology of Tendons in Fluoroquinolone-Induced Achilles Tendinopathy

Fluoroquinolones (FQs), especially Pefloxacin (PEF) have been reported to increase risk of Achilles tendon rupture. However, prior studies showed that intrasound therapy (ITR) significantly improved the morphology of the healing tendon. This study aimed to compare the effects of 7, 14 and 21 days intrasound treatment on the mechanical properties and morphology of the Achilles tendon in fifty (50) male Sprague-Dawley rats induced with FQ and randomized into three main categories designated as Normal control (A), Experimental control (B) and Treatment groups (C). All animals in groups B and C were orally administered PEF 400mg/kg in a fixed volume of 2.5 ml/kg daily for 6 consecutive days. The Achilles tendon of both hind limbs in group C were treated with the lowest intensity ITR 5 minutes daily for 7, 14 and 21 consecutive days. All the animals were serially sacrificed on days 8, 15 and 22 and the tendons excised and processed. Data were analyzed with RSTUDIO version 4.0.02 and the level of significance set at 0.05. Kruskal Wallis showed no significant differences (p >0.05) in all the biomechanical parameters across all the groups. Compared with group B, ITR 14 days treatment had the best improvement in all biomechanical variables, though insignificant (p>0.05). In the Intrasound groups, there were significant positive correlations of Nitric Oxide Synthase (NOS) with ultimate tensile stress and tensile load (p= 0.005; p=0.003) respectively. Intrasound treatment to the Achilles tendon for 14 days improved the mechanical properties and morphology of tendons in Fluoroquinolone-induced tendinopathy.

Clinico-toxicological effects of ceftriaxone after intramuscular administration of graded doses in Basenji dogs

Purpose: The recent ceftriaxone-induced anaemia and mortalities at the dose of 50 mg/kg in Veterinary Teaching Hospital, University of Nigeria prompted this study which sought to assess the clinicotoxicological effects of ceftriaxone (CFZ) after intramuscular administration of graded doses in Basenji dogs.Methods: The effects of CFZ on the haematological indices, physiological parameters, liver and kidney functions were assessed in 4 group of dogs (n = 4) designated A – D. They were given CFZ intramuscularly for 21 days at doses of 12, 25 and 50 mg/kg for groups A, B, C, respectively, while thecontrol (group D) received the diluent (lignocaine 0.2 mL)Results: The mean pulse and heart rate of dogs in group C were significantly (p < 0.05) higher than those of group A, B and D. Significant (p < 0.05) decrease in red blood cell count (RBC), haemoglobin concentration (Hb) and packed cell volume (PCV) was observed in group C on days 7 and 14, while on day 21, these parameters were significantly (p < 0.05) higher in group D than in the treated groups. On day 14 of CFZ administration, the alanine transaminase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activities of dogs in group C was significantly (p < 0.05) elevated than the control group.Conclusion: These findings suggest that CFZ, at the doses of 12.5 - 25 mg/kg, appears safe in dogs as most of the adverse effects observed are reversed following the withdrawal of the drug on day 28. However, CFZ at 50 mg/kg causes anaemia, tachycardia and bilateral paralysis of the hind limbs which did not revert to normal after one week; hence, it is not recommended for use in dogs at this dose.