Effective and tolerable salvage therapies for elderly patients with chemorefractory acute myeloid leukemia (AML) are limited and usually do not change the poor clinical outcome. We recently described in several chemorefractory elderly AML patients that a novel biomodulatory treatment regimen consisting of low-dose azacitidine (AZA) in combination with PPARγ agonist pioglitazone (PGZ) and all-trans retinoic acid (ATRA) induced complete remission of leukemia and also triggered myeloid differentiation with rapid increase of peripheral blood neutrophils. Herein, we further investigated our observations and comprehensively analyzed cell differentiation in primary AML blasts after treatment with ATRA, AZA, and PGZ ex vivo. The drug combination was found to significantly inhibit cell growth as well as to induce cell differentiation in about half of primary AML blasts samples independent of leukemia subtype. Notably and in comparison to ATRA/AZA/PGZ triple-treatment, effects on cell growth and myeloid differentiation with ATRA monotherapy was much less efficient. Morphological signs of myeloid cell differentiation were further confirmed on a functional basis by demonstrating increased production of reactive oxygen species as well as enhanced phagocytic activity in AML blasts treated with ATRA/AZA/PGZ. In conclusion, we show that biomodulatory treatment with ATRA/AZA/PGZ can induce phenotypical and functional differentiation of primary AML blasts into neutrophil like cells, which aside from its antileukemic activity may lower neutropenia associated infection rates in elderly AML patients in vivo. Clinical impact of the ATRA/AZA/PGZ treatment regimen is currently further investigated in a randomized clinical trial in chemorefractory AML patients (NCT02942758).

A 4-year-old Doberman Pinscher was evaluated for chronic progressive central vestibular disease and aggressiveness. A cyst-like lesion was identified in the region of the left cerebellopontine angle. The lesion was hypointense on T1-weighted and hyperintense on T2-weighted images. Differentials included an epidermoid or dermoid cyst, cystic neoplasm, and brain abscess. Hyperintensity on subsequent fluid-attenuated inversion recovery images excluded an arachnoid cyst. The histopathologic diagnosis was epidermoid cyst within the fourth ventricle.

Dental disorders are one of the top-ranking clinical domains in equine practice. Scintigraphy has emerged as a useful diagnostic imaging modality for equine dental diseases. There is a paucity of the normal scintigraphic uptake and its correlation with age. This prospective, cross-sectional, descriptive and pilot-designed study aimed to describe the radioisotope uptake (RU) patterns of the reserved crown and periodontal bone of the maxillary and mandibular cheek teeth (CT) in clinically sound horses and to evaluate the age effect on RU. For this purpose, 60 horses that underwent a bone scintigraphy for reason unrelated to head were included and divided equally into four age groups. Regions of interests (ROIs) were positioned around alveolar and periodontal bone of each maxillary and mandibular CT including their reserve crown, and a reference ROI positioned at the mandibular ramus. The count per pixel of each ROI was measured using a dedicated software and the RU ratio relative to the reference region was calculated. The results showed that the maxillary and mandibular CT had a standard RU pattern, where it increased from rostral to caudal, and peaked in the middle of dental arcades and decreased slightly towards the last CT. The maxillary CT had a higher RU compared with the mandibular CT, and there was no significant difference in the maxillary and mandibular CT uptake between age groups. This information may aid veterinarians evaluating potentially abnormal dental scintigraphy.

The use of bioabsorbable screws for fixation of proximal fractures of the splint bone appears to be a safe and feasible technique and may offer several advantages over the use of traditional metallic implants.

The equine thyroid gland is a bilobed organ, which is located in the dorsolateral aspect of the third to sixth tracheal ring (Viana et al., 2019). The embryonic ultimobranchial body is an outpocketing of the fourth pharyngeal pouch that fuses with the thyroid diverticulum, giving rise to calcitonin-producing C-cells (David et al., 2008;Saulez et al., 2012). Cysts or cyst-like lesions in adult equine thyroid glands are quite uncommon (Østergaard et al., 2014). Clinically, these cysts emerge as a well-defined, fluctuating mass in the perilaryngeal region. The masses are not painful at palpation and their appearance is often similar to branchial apparatus anomalies, like remnant cysts, sinuses and fistulae (Østergaard et al., 2014;Slovis et al., 2006).The differential diagnoses of thyroid cyst include thyroglossal duct cyst, branchial cyst, oesophageal and tracheal duplication cysts, and salivary mucocele (Kelmer et al., 2007). Consequently, the use of diagnostic imaging is crucial for an in-depth diagnosis and appropriate treatment. In the literature, pharyngeal endoscopy and ultrasound examination accompanied by plain or contrast radiography have been described in thyroid cystic masses in horses (Rinnovati et al., 2018). By using ultrasonography, a comparison of the size between the left and right thyroid lobe can be easily made (Viana et al., 2019). However, neither ultrasonography nor contrast radiography can identify the exact size of the cyst and more importantly, the relationship between the cyst and adjacent vital organs. For this reason, advanced imaging modalities are extremely useful in these cases, especially the use of standing computed tomography (Peters et al., 2003). Before surgical removal of one or both thyroid lobes, it is recommended to test the thyroid function. This can be achieved via measuring the serum thyroid hormone concentrations. However, the concentration of thyroid hormones have seasonal and diurnal variation, which may complicate the interpretation (Wallack et al., 2010). Technetium pertechnetate is an iodine analogue, so it is transported to the thyroid gland similarly to iodine (Iqbal & Rehman, 2020). That makes thyroid scintigraphy a suitable diagnostic method to assess the metabolic activity and the detection of functional disparity between the lobes of thyroid glands (Iqbal & Rehman, 2020). The presented report describes the diagnostic methodology of a thyroid cyst in a mature horse using ultrasonography, computed tomography (CT) and scintigraphy. The conservative management by sclerotherapy and positive long-term outcome 2 years' post treatment are reported.