Doppler ultrasonography can be used to evaluate the arterial blood supply of hip joints in skeletally immature cats.

OBJECTIVE: To investigate hemodynamics and morphology of hip joint vasculature in cats with the use of color and pulsed-wave Doppler ultrasonography. ANIMALS: 30 client-owned healthy skeletally immature cats presented for routine examinations between September 7, 2022, and March 25, 2023. METHODS: Cats between 3.5 to 18 months old with healthy hip joints and Hct within reference ranges (26% to 44.2%) were eligible for inclusion. Color and pulsed-wave Doppler ultrasonography was performed without sedation. Peak systolic velocity (PSV), mean diastolic velocity (MDV), resistance index (RI), and pulsatility index (PI) were measured for major arteries of the hip joints. RESULTS: Intermediate pulsatility, resistance to flow, and pandiastolic anterograde flow were evident for all arteries evaluated for each joint except for the ligamentum capitis ossis femoris artery (LCOFA). Spectral waveforms for the LCOFA showed a low-resistance pattern with continuous forward diastolic flow. No significant differences were found in the mean PI or MDV between the left and right sides for the ascending branch of the lateral circumflex femoral artery or in the mean PI of the ascending branch of the medial circumflex femoral artery. Mean PSV of the LCOFA was lower (but nonsignificantly) for left hip joints vs right hip joints, whereas other values were often higher on cats' left side vs their right. CLINICAL RELEVANCE: This study provided insight into the morphology and hemodynamics of the femoral head vasculature in skeletally immature cats and showed Doppler ultrasound values to study the clinically normal blood supply to hip joints in cats.

Transcriptomic and in vivo approaches introduced human iPSC-derived microvesicles for skin rejuvenation.

The skin undergoes the formation of fine lines and wrinkles through the aging process; also, burns, trauma, and other similar circumstances give rise to various forms of skin ulcers. Induced pluripotent stem cells (iPSCs) have become promising candidates for skin healing and rejuvenation due to not stimulating inflammatory responses, low probability of immune rejection, high metabolic activity, good large-scale production capacity and potentials for personalized medicine. iPSCs can secrete microvesicles (MVs) containing RNA and proteins responsible for the normal repairing process of the skin. This study aimed to evaluate the possibility, safety and effectiveness of applying iPSCs-derived MVs for skin tissue engineering and rejuvenation applications. The possibility was assessed using the evaluation of the mRNA content of iPSC-derived MVs and the behavior of fibroblasts after MV treatment. Investigating the effect of microvesicle on stemness potential of mesenchymal stem cells was performed for safety concerns. In vivo evaluation of MVs was done in order to investigate related immune response, re-epithelialization and blood vessel formation to measure effectiveness. Shedding MVs were round in shape distributed in the range from 100 to 1000 nm in diameter and positive for AQP3, COL2A, FGF2, ITGB, and SEPTIN4 mRNAs. After treating dermal fibroblasts with iPSC-derived MVs, the expressions of collagens Iα1 and III transcripts (as the main fibrous extracellular matrix (ECM) proteins) were upregulated. Meanwhile, the survival and proliferation of MV treated fibroblasts did not change significantly. Evaluation of stemness markers in MV treated MSCs showed negligible alteration. In line with in vitro results, histomorphometry and histopathology findings also confirmed the helpful effect of MVs in skin regeneration in the rat burn wound models. Conducting more investigations on hiPSCs-derived MVs may lead to produce more efficient and safer biopharmaceutics for skin regeneration in the pharmaceutical market.

Direct pulp capping with autologous bone marrow derived stem cells in dogs.

Bone-marrow derived stem cells (BMSCs) can differentiate into several mesenchymal cell lines that are suitable for bone and dental tissue engineering. This study was aimed to assess the efficacy of cell therapy in direct pulp capping (DPC) of canine teeth using autologous BMSCs along with collagen/hydroxyapatite hybrid scaffold in terms of the quantity and quality of calcified bridge formation. The teeth were randomly divided into three groups of DPC with mineral trioxide aggregate (MTA), hydroxyapatite/collagen hybrid scaffold alone and BMSCs with hydroxyapatite/collagen hybrid scaffold. DPC was performed under general anesthesia in cavities prepared on the buccal surfaces of mandibular and maxillary premolars of the same dogs from which, stem cells had been isolated. All cavities were then restored with light-cure resin modified glass ionomer cement. Histomorphometric assessments after 12 weeks showed formation of dentinal bridge following DPC with BMSCs and MTA. The efficacy of MTA for calcified bridge formation following DPC was significantly higher than that of BMSCs plus hybrid scaffold. According to the present study, we concluded DPC using BMSCs and hybrid scaffold did not provide clinically noticeable results in canine patients.

Introducing a noninvasive, non-surgical, and reversible animal model for fecal incontinence using abobotulinumtoxinA in dogs.

The aim of this study was to introduce a new animal model of fecal incontinence (FI) by injecting abobotulinumtoxinA in the external anal sphincter (EAS) muscle of dogs which replaces models based on anal sphincter destructions that are invasive, mostly require surgical procedures, expensive, permanent, and painful to the animals. 4 healthy mongrel dogs were used in this study. First, they were received NaCl 0.09% (as control) injections in EAS muscle and effects were assessed by means of Electromyography (EMG) and clinically evaluated by sphincter pinch test and presence of leakage of feces for 2 weeks. Then, they received abobotulinumtoxinA in EAS muscle and reevaluated for 6 weeks to see short-term and medium-term effects of abobotulinumtoxinA injection. Saline had no significant changes in results obtained from EMG, however, there were significant decreases in amplitudes of action potentials after receiving abobotulinumtoxinA in comparison with no injection or saline injection in EAS muscle. Pinch tests were normal after saline injection assessment period, however, then started to be negative, ranging from two days after abobotulinumtoxinA injection to seven days after receiving abobotulinumtoxinA. Animals also had significant presentations of fecal incontinence (leakage of feces and cage contamination with feces) from the 1st week after receiving abobotulinumtoxinA until the 6th week after receiving abobotulinumtoxinA. AbobotulinumtoxinA caused paralysis in the EAS and producd FI conditions in dogs. This animal model was an appropriate substitute to the various invasive, expensive and also complicated procedures with an easy, feasible, noninvasive and non-painful single-stage abobotulinumtoxinA injection.

Effect of center of rotation of angulation-based leveling osteotomy on ex vivo stifle joint stability following cranial cruciate ligament transection and medial meniscal release with and without a hamstring load.

OBJECTIVE: To evaluate the effect of center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) and hamstring load on stifle stability following cranial cruciate ligament transection (CCLx) and medial meniscal release (MMR). STUDY DESIGN: Ex vivo experimental study. SAMPLE POPULATION: Cadaver hind limb preparations (n = 7). METHODS: After instrumentation, constant quadriceps and gastrocnemius loads with an optional hamstring load in a 3:1:0.6 ratio were applied, and stifles were extended from fully flexed using an electrical motor during fluoroscopic recording. The recording process was repeated after each of CCLx, MMR and CBLO and the extracted landmark coordinates were used for calculation of cranial tibial translation (CTT) and patellar ligament angle (PTA). RESULTS: Mean initial tibial plateau angle was 28.1°: post-CBLO the mean was 9.7°. Cranial tibial translation developed from 50° and 75° with CCLx and MMR respectively (p < .04, < .02) without hamstring loading. Hamstring loading mitigated CTT due to CCLx and delayed CTT until 120° for MMR (P < .02) in this model. CBLO prevented CTT, except at 140° without hamstring loading (P = .01). Similar results were seen for PTA, but CBLO curves were parallel to and lower than intact values at all tested angles (P < .04), consistent with induced effective joint flexion. CONCLUSION: CBLO to a target tibial plateau angle of 10° largely eliminated CTT induced by CCLx and MMR. Hamstring loads of 20% quadriceps load improved stifle stability in this model. IMPACT: Stifle stability following CBLO appears to be multifactorial and depends on meniscal integrity, joint angle, and hamstring strength.

Therapeutic effects of simultaneous Photobiomodulation therapy (PBMT) and Meloxicam administration on experimental acute spinal cord injury: Rat animal model.

STUDY DESIGN: Application of Photobiomodulation therapy (PBMT) and meloxicam in acute spinal cord injury, functional recovery and histological evaluation. OBJECTIVE: Evaluation of the effect of simultaneous PBMT and meloxicam on treatment of acute experimental spinal cord injury and comparing it with the effect of application of each of them separately. SETTING: The study was conducted at the Department of Surgery & Radiology, Faculty of Veterinary Medicine and Institute of Biomedical Research, University of Tehran, Tehran, Iran. METHODS: Twenty four rats were used in this study. A compression injury was induced to the T8-T9 segment of the spinal cord of rats using a Fogarty embolectomy catheter. Rats were randomly divided into 4 groups including: Control group, PBMT (810 nm-200 mw-8 s-2 weeks) group, Meloxicam (1 mg/kg) group, and PBMT and Meloxicam (mixed) group. After inducing injury, hind limb performance of the rats was evaluated, using BBB test and then treatment intervention was performed and continued for 2 weeks. RESULTS: Four  weeks after injury induction, BBB test results were significantly higher in all treatment groups in comparison to control group, however, there were no significant differences among the treatment groups. In addition, histological findings revealed no significant difference between all 4 study groups. CONCLUSION: According to the results of this study we can conclude that simultaneous and separate application of PBMT and Meloxicam play an effective role in treatment of acute spinal cord injuries.

The healing effect of nettle extract on second degree burn wounds.

BACKGROUND: Numerous studies were carried out to develop more sophisticated dressings to expedite healing processes and diminish the bacterial burden in burn wounds. This study assessed the healing effect of nettle extract on second degree burns wound in rats in comparison with silver sulfadiazine and vaseline. METHODS: Forty rats were randomly assigned to four equal groups. A deep second-degree burn was created on the back of each rat using a standard burning procedure. The burns were dressed daily with nettle extract in group 1, silver sulfadiazine in group 2, vaseline in group 3 and without any medication in group 4 as control group. The response to treatment was assessed by digital photography during the treatment until day 42. Histological scoring was undertaken for scar tissue samples on days 10 and 42. RESULTS: A statistically significant difference was observed in group 1 compared with other groups regarding 4 scoring parameters after 10 days. A statistically significant difference was seen for fibrosis parameter after 42 days. In terms of difference of wound surface area, maximal healing was noticed at the same time in nettle group and minimal repair in the control group. CONCLUSION: Our findings showed maximal rate of healing in the nettle group. So it may be a suitable substitute for silver sulfadiazine and vaseline when available.

Evaluation of Effects of Intraperitoneal CO2 Pressure in Laparoscopic Operations on Kidney, Pancreas, Liver and Spleen in Dogs.

BACKGROUND: During laparoscopy, insufflation of an inert gas in the peritoneal cavity creates a working space to facilitate surgery. The space should be large enough to facilitate surgery without increasing intra-abdominal pressure (IAP) over a threshold limit (usually 15 mm Hg). OBJECTIVES: This experimental study was performed to evaluate the effects of increasing in intra-abdominal pressure on internal organs. MATERIALS AND METHODS: Twenty female mixed breed dogs (20 ± 3 kg, 18 ± 1.2 months) were selected. They were randomly divided to two groups (n = 10). The intra-abdominal pressure was maintained 12 mm Hg and 20 mm Hg during the operation in control group and in test group respectively. RESULTS: Histopathologic evaluations revealed more pathological changes at the kidney of all the dogs in test group in comparison to control group. CONCLUSIONS: Our findings revealed that organs that their blood supplies are related to one single or two arteries and their blood drainage are related to one or two veins are more sensitive to increased intra-abdominal pressure.

The effect of enoxaparin and clopidogrel on survival of random skin flap in rat animal model.

BACKGROUND: Necrosis of skin flaps is considered as an important complication in reconstructive surgery. We conducted an experimental study to investigate the efficacy of low-molecular weight heparin, clopidogrel and their combination to improve the flap survival. METHODS: Forty male, adult Sprague-Dawlay rats were divided randomly into 4 groups. Standard rectangular, distally based dorsal random pattern skin flap was elevated. To prevent the graft effect, a sterile sheet was put under the flap. No pharmacological agent was administered for the control group. In group 2, single subcutaneous dose of enoxaparin (3.2 mg/kg) was immediately administrated after surgery. In group 3, clopidogrel (25 mg/kg) was given orally for 7 days. In group 4, both enoxaparin and clopidogrel were administrated. The rats were evaluated on post-operative day 7 for viable and necrotic portions of flaps. RESULTS: The mean and SD of necrosis was 17.79+2.5 cm in the control group, 16.20±3.1 cm in low-molecular weight heparin, 15.25+3.8 cm in combined therapy group and 13.69+2.7 cm in clopidogrel group. Clopidogrel was the only pharmaceutical agent that produced a significant increase in the flap survival area. CONCLUSION: Clopidogrel may be an effective pharmaceutical agent that significantly increases viability of random skin flaps in rats, but low-molecular weight heparin and their combination did not have any significant beneficial effects.