A Hexokinase 2 Modulator for Field-Directed Treatment of Experimental Actinic Keratoses.

Overexpression of hexokinase 2, and its binding to VDAC1 on the outer mitochondrial membrane of cancer cells, is key to their metabolic reprogramming to aerobic glycolysis, which enables them to proliferate. We describe Comp-1, an allosteric small molecule that selectively detaches hexokinase 2 from the mitochondria. Detachment of hexokinase 2 reduces glycolysis and triggers apoptosis in cancer cells, without affecting hexokinase 1-expressing normal cells. The anti-cancer activity of Comp-1 was demonstrated in the UVB-damaged skin model in SKH-1 mice. Topical treatment with Comp-1 led to 70% reduction in lesion number and area. This in vivo efficacy was obtained without local skin reactions or other safety findings. Mechanism-related pharmacodynamic markers, including hexokinase 2 and cleaved caspase 3 levels, are affected by Comp-1 treatment in vivo. Good Laboratory Practice toxicology studies in minipigs for 28 days and 13 weeks established no systemic toxicities and minimal dermal reaction for once-daily application of up to 20% and 15% ointment strengths, respectively. Thus, Comp-1 may address a significant unmet medical need for a non-irritating efficacious topical actinic keratosis treatment.

Photobiomodulation Triple Treatment in Peripheral Nerve Injury: Nerve and Muscle Response.

BACKGROUND: Muscle preservation or decrease in muscle degeneration and progressive atrophy are major challenges in patients with severe peripheral nerve injury (PNI). Considerable interest exists in the potential therapeutic value of laser phototherapy (photobiomodulation) for restoring denervated muscle atrophy and for enhancing regeneration of severely injured peripheral nerves. As previously published, the laser phototherapy has a protective and immediate effect in PNI. Laser phototherapy in the early stages of muscle atrophy may preserve the denervated muscle by maintaining creatinine kinase (CK) activity and the amount of acetylcholine receptor (AChR). OBJECTIVE AND METHODS: In the present study, the effectiveness of triple treatment laser phototherapy, namely, applied simultaneously at three areas: injured area of the peripheral nerve, corresponding segments of the spinal cord, and corresponding denervated muscle (triple treatment), was evaluated for the treatment of incomplete PNI in rats with the ultimate goal of achieving improved limb function. RESULTS: Forty-five days after the sciatic nerve insult, all rats regained normal walking (functional sciatic index values returned to baseline); however, the long laser irradiation (7 min) group presented the fastest recovery as opposed to short laser irradiation (3 min). A histological evaluation of the nerves revealed that long laser irradiation led to a higher amount of neuronal fibers that were larger than 4 µm (543 ± 76.8, p < 0.01) than short irradiation (283 ± 35.36). A histological evaluation of muscular atrophy showed that long laser irradiation evolved with significantly less muscle atrophy (8.06% ± 1.23%, p < 0.05) than short irradiation (24.44% ± 7.26%). CONCLUSIONS: The present study and our previous investigations showed that the laser phototherapy increases biochemical activity and improves morphological recovery in muscle and, thus, could have direct therapeutic applications on muscle, especially during progressive atrophy resulting from PNI.

Combining Sodium Hyaluronate and Polyvinylpyrrolidone Therapies for the Rabbit Cornea: A New Approach to Relief of the Human Dry Eye Syndrome.

PURPOSE OF THE STUDY: The novel combination of 0.1% sodium hyaluronate (HA) and 5.0% polyvinylpyrrolidone (PVP) into one eyedrop was investigated to test the hypothesis of its increased relief of dry eye syndrome (DES). MATERIALS AND METHODS: We evaluated HA and PVP, either alone, or in combination, by utilizing 16 rabbits, where their right eyes received one or two different eyedrops, and their left eyes, as controls, received none. The DES replica in rabbits was induced by 0.1% benzalkonium chloride (BAC) eyedrops. BAC was instilled into the right eyes of all rabbits, which were divided into four groups of four. In Group 1 M, the rabbits received only BAC. A second eyedrop given to the right eyes of Group 2 M was HA, of Group 3 M was PVP, and of Group 4 M was the combination of both HA and PVP. All eyes were followed clinically for 14 d, and thereafter, examined histopathologically. RESULTS: Clinically, the HA+PVP combination yielded the least perilimbal conjunctival erythema (p < 0.05), and the least corneal epithelial fluorescein staining (p < 0.001) compared to each treatment alone. Histopathologically, all four rabbits' right eyes in the combination group 4 M displayed the greatest preservation of the corneal epithelium (p < 0.001) and of the perilimbal conjunctival goblet cell density (p < 0.001). CONCLUSIONS: This unique combination of both HA and PVP into one eyedrop, was more potent than either treatment alone in protecting the ocular surface. A preparation, containing both HA and PVP may become useful for DES patients.

Morphometry of skin changes in Newfoundland dogs following coat clipping.

Dog breeds are unique in their coat conformation and quality. Newfoundland dogs have a long and fine hair coat, and clipping may induce changes in newly grown hair. This study examined structural changes in the skin of Newfoundland dogs following clipping. Dogs included in the study had visible coat changes following clipping that appeared as loss of gloss, increased scaling and textural changes. The control groups consisted of two groups of dogs that had never been clipped: Newfoundland dogs served as within-breed controls, and long-haired dogs of other breeds served as between-breed controls. All dogs were healthy with no history of dermatological problems. Two skin biopsies were taken from each dog and evaluated for predetermined parameters. A total of 41 samples were examined: 11 from clipped Newfoundland dogs, 16 from unclipped ones, and 14 from dogs of other breeds. By histopathology, the clipped dogs had a thicker cornified layer (P=0.006) and smaller sebocytes (P=0.022) than the unclipped ones. Newfoundlands had larger and more epitrichial sweat glands than other breeds (P=0.0002, P=0.036, respectively), and those were not affected by clipping. These results suggest that hyperkeratosis and decreased sebocyte size may explain the observed coat changes following clipping in Newfoundland dogs.

Chondroma of the vertical ramus of the feline mandible.

A 5-year-old, castrated male, domestic shorthair cat presented with firm swelling in the right temporal region of the skull. The cat's jaws were almost locked in the closed position. Radiographs showed a mass with an irregular mineralized matrix superimposed on the caudal right mandible and temporomandibular joint. Surgical exploration revealed that the mass arose from the proximal part of the vertical ramus, which was removed, with the exclusion of the temporomandibular joint. It was possible to open the cat's mouth to nearly normal extension immediately after surgery. Recovery was uneventful - the cat has had no problem eating and no mass recurrence has been detected 3 years after surgery. Histological examination of the mass was consistent with chondroma. To the best of our knowledge, this is the first clinical and pathological description of a chondroma in cats, and one of the rare cases describing clinical presentation and management of primary bone tumours involving the vertical ramus of the feline mandible.

Disseminated central nervous system disease caused by Trypanosoma evansi in a horse.

Trypanosomiasis caused by Trypanosoma evansi ("Surra") is mainly a wasting disease affecting equids, camels and cattle as well as other domestic and wild animal species. In horses, infection may cause severe neurological abnormalities; however, the clinical progression, pathogenesis and molecular ante-mortem detection of this form of the disease have not been described in detail. A mare with progressive ataxia, head tilt, nystagmus and cranial nerve deficits submitted to treatment was diagnosed with central nervous system trypanosomiasis following the detection of a Trypanosoma tryposmastigote in cerebrospinal fluid cytology. Histopathology following necropsy showed that the brain, spinal cord and kidneys were the main affected tissues with disseminated multifocal non-suppurative meningoencephalitis of the central nervous system and membranoproliferative glomerulonephritis. Serology for T. evansi was positive and PCR indicated the presence of parasite DNA in the cerebellum, brain stem, spinal cord and bone marrow but not in other organs and confirmed the identity of causative agent as T. evansi. This is the first report of ante-mortem detection of T. evansi in the cerebrospinal fluid of a horse and the first description of post-mortem PCR identification of the parasite DNA in the nervous system.

A method for intervertebral space distraction before stabilization combined with complete ventral slot for treatment of disc-associated wobbler syndrome in dogs.

OBJECTIVE: To evaluate the use of a modified K-wire spacer for maintaining intervertebral distraction after ventral decompression and during stabilization as a treatment for disc-associated wobbler syndrome in large breed dogs. STUDY DESIGN: A retrospective study. ANIMALS: Dogs (n=7) with disc-associated wobbler syndrome. METHODS: Medical records (2003-2006) of dogs treated by a modified surgical method were evaluated. Data retrieved were signalment, onset and duration of clinical signs, neurologic abnormalities, diagnostic methods, surgical procedure, immediate, and long-term (>or=1 year) postoperative clinical and radiographic outcome. RESULTS: Mean duration of clinical signs was 4.8 months. Neurologic signs included ataxia (2), ambulatory tetraparesis (2), and non-ambulatory tetraparesis (3). Three dogs had disc protrusion in 2 sites, 2 dogs had the procedure in 1 location and stabilization of both affected sites. All dogs improved dramatically and remained for 1-3 years. One dog had recurrence of cervical discomfort 13 months later. CONCLUSIONS: Despite the limited number of dogs, overall initial successful outcome with only 1 dog having mild recurrence 13 months later supports further use and evaluation of this technique. CLINICAL RELEVANCE: Distraction using a K-wire spacer after ventral decompression followed by stabilization should be considered in dogs with disc-associated wobbler syndrome to prevent collapse of the intervertebral space.

Resolution of renal adenocarcinoma-induced secondary inappropriate polycythaemia after nephrectomy in two cats.

Two cases of secondary, inappropriate polycythaemia caused by renal adenocarcinoma in domestic shorthair cats, are described. The cats were 9 and 12 years old and both were presented because of generalised seizures presumably due to hyperviscosity. Both cats had a markedly increased haematocrit (0.770 and 0.632 l/l) and thrombocytosis (744 x 10(9)/l and 926 x 10(9)/l). An abdominal ultrasound revealed a mass in the cranial pole of one kidney in both cats. Serum erythropoietin (EPO) concentration was within the reference interval (RI) in both cats but was inappropriately high considering the markedly increased haematocrit. The cats were initially stabilised and managed by multiple phlebotomies and intravenous fluid therapy and underwent nephrectomy of the affected kidney later on. Both the polycythaemia and thrombocytosis resolved following surgery. Postoperative serum EPO concentration, measured in one cat, decreased markedly. Histopathology of the affected kidneys confirmed a diagnosis of renal adenocarcinoma. Both cats were stable for an 8-month follow-up period; however, one cat had developed a stable chronic kidney disease (CKD), while the other was represented 8 months postoperatively due to dyspnoea, and had radiographic evidence of lung metastasis, presumably because of the spread of the original renal tumour and was euthanased. Initial stabilisation of polycythaemic cats should include multiple phlebotomies. Nephrectomy should be considered in cats with secondary, inappropriate, renal adenocarcinoma-related polycythaemia when only one kidney is affected by the tumour, and provided that the other kidney's function is satisfactory. Nephrectomy should be expected to resolve the polycythaemia and lead to normalisation of serum EPO concentration.

Detection of Ehrlichia canis by PCR in different tissues obtained during necropsy from dogs surveyed for naturally occurring canine monocytic ehrlichiosis.

A molecular study for the detection of Ehrlichia canis was carried out on tissues obtained at necropsy from randomly selected dogs with the intention of investigating naturally-occurring canine ehrlichiosis. The tissues evaluated for the presence of E. canis included lymph nodes, spleen, liver, bone marrow, and blood. Eight of the 18 dogs included were found to be positive for E. canis by polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene. Two dogs were positive for Anaplasma platys of which one dog was co-infected with E. canis and A. platys. Blood (5/8) and lymph nodes (5/8) were the tissues found to yield the highest number of positive E. canis PCR results with 7/8 dogs positive in the blood or lymph node. E. canis and A. platys DNA could be amplified by PCR when tissue samples were obtained 72h after the time of death.