Comparison of a Minimally Invasive Transthoracic Approach and a Surgical Method for Intrapleural Injection of Tumor Cells in Mice.

Intrapleural injections can be used in mice to deliver therapeutic and diagnostic agents and to model human disease processes (for example, pleural fluid accumulation, malignant pleural disease, and lung cancers). In the context of establishing cancer models, minimally invasive methods of intrapleural injection are desirable because inflammation at the injection site can have a major impact on tumor growth and progression. Common approaches for intrapleural injection include surgical exposure of the thoracic wall or the diaphragm prior to injection; however, these invasive procedures require tissue dissection that triggers an undesirable inflammatory response and increases the risk of pneumothorax. While nonsurgical procedures can minimize this concern, 'blind' injections may lead to off target inoculation. In this study, we hypothesized that a minimally invasive transthoracic approach (MI-TT) would produce a tumor distribution and burden similar to that of a surgical transabdominal approach (SX-TA). Prior to performing the procedures on live mice, surgeons were trained using cadavers and terminal procedures. Then a total of 14 nude mice (female, 4 to 6 wk old) were injected with 50 µL (5 million) A549-Luc2 human cancer cells either using the MI-TT (n = 8) or SX-TA (n = 6) approach under carprofen analgesia and isoflurane anesthesia. Our results indicate that with training, a minimally invasive transthoracic approach for intrapleural injection provides more consistent tumor placement and a greater tumor burden than does the surgical method. However, additional studies are necessary to confirm anatomic placement and characterize tumor profiles.

Comparison of Low- and High-temperature Cagewash Cycles for Sanitation of Rodent Housing Equipment in Research Facilities.

Sanitation guidelines for animal research facilities state that disinfection is achieved by application of high-temperature water (143 to 180 °F [62 to 82 °C]) or detergents and disinfectants. However, these guidelines are based on requirements for pasteurization, which may be unnecessarily stringent for the sanitation of nonfood items and do not address the theoretical sanitation potential of water at temperatures below 143 °F (62 °C). Recent literature indicates that water temperatures below 143 °F (62 °C) can also provide effective sanitation. In this study, we compared cagewash cycles at low (100 °F [38 °C] and 120 °F [49 °C]) and high (standard) (180 °F [82 °C]) temperatures and evaluated sanitation efficacy by using ATP swabs and RODAC plates. Low-temperature loads were washed either with or without prior treatment of a chemical disinfectant (10% bleach). The 100 °F (38 °C) cycle was not sufficient for sanitization without bleach pretreatment. However, the 120 °F (49 °C) cycle effectively sanitized cages without bleach pretreatment. Validation of effective sanitation at a lower water temperature (120 °F [49 °C]) can improve cagewash logistics and reduce costs as compared with standard (180 °F [82 °C]) high-temperature cycles.

Tibial nerve stimulation increases vaginal blood perfusion and bone mineral density and yield load in ovariectomized rat menopause model.

INTRODUCTION AND HYPOTHESIS: Human menopause transition and post-menopausal syndrome, driven by reduced ovarian activity and estrogen levels, are associated with an increased risk for symptoms including but not limited to sexual dysfunction, metabolic disease, and osteoporosis. Current treatments are limited in efficacy and may have adverse consequences, so investigation for additional treatment options is necessary. Previous studies have demonstrated that percutaneous tibial nerve stimulation (PTNS) and electro-acupuncture near the tibial nerve are minimally invasive treatments that increase vaginal blood perfusion or serum estrogen in the rat model. We hypothesized that PTNS would protect against harmful reproductive and systemic changes associated with menopause. METHODS: We examined the effects of twice-weekly PTNS (0.2 ms pulse width, 20 Hz, 2× motor threshold) under ketamine-xylazine anesthesia in ovariectomized (OVX) female Sprague-Dawley rats on menopause-associated physiological parameters including serum estradiol, body weight, blood glucose, bone health, and vaginal blood perfusion. Rats were split into three groups (n = 10 per group): (1) intact control (no stimulation), (2) OVX control (no stimulation), and (3) OVX stimulation (treatment group). RESULTS: PTNS did not affect serum estradiol levels, body weight, or blood glucose. PTNS transiently increased vaginal blood perfusion during stimulation for up to 5 weeks after OVX and increased areal bone mineral density and yield load of the right femur (side of stimulation) compared to the unstimulated OVX control. CONCLUSIONS: PTNS may ameliorate some symptoms associated with menopause. Additional studies to elucidate the full potential of PTNS on menopause-associated symptoms under different experimental conditions are warranted.

Anesthetic agents affect urodynamic parameters and anesthetic depth at doses necessary to facilitate preclinical testing in felines.

Urodynamic studies, used to understand bladder function, diagnose bladder disease, and develop treatments for dysfunctions, are ideally performed with awake subjects. However, in small and medium-sized animal models, anesthesia is often required for these procedures and can be a research confounder. This study compared the effects of select survival agents (dexmedetomidine, alfaxalone, and propofol) on urodynamic (Δpressure, bladder capacity, bladder compliance, non-voiding contractions, bladder pressure slopes) and anesthetic (change in heart rate [∆HR], average heart rate [HR], reflexes, induction/recovery times) parameters in repeated cystometrograms across five adult male cats. The urodynamic parameters under isoflurane and α-chloralose were also examined in terminal procedures for four cats. Δpressure was greatest with propofol, bladder capacity was highest with α-chloralose, non-voiding contractions were greatest with α-chloralose. Propofol and dexmedetomidine had the highest bladder pressure slopes during the initial and final portions of the cystometrograms respectively. Cats progressed to a deeper plane of anesthesia (lower HR, smaller ΔHR, decreased reflexes) under dexmedetomidine, compared to propofol and alfaxalone. Time to induction was shortest with propofol, and time to recovery was shortest with dexmedetomidine. These agent-specific differences in urodynamic and anesthetic parameters in cats will facilitate appropriate study-specific anesthetic choices.

In vitro MSC function is related to clinical reaction in vivo.

BACKGROUND: We recently demonstrated that intracellular xenogen-contaminated autologous MSCs (FBS) and non-xenogen-contaminated allogeneic (ALLO) MSCs caused an adverse clinical response after repeated intra-articular injection in horses, whereas autologous (AUTO) MSCs did not. Our current objective was to use clinical data from the previous study to compare MSC stemness against adverse response indicated by synovial total nucleated cell count (TNCC) following intra-articular MSC injection. METHODS: Stemness, quantified by a trilineage differentiation (TLD) score; immunomodulation, quantified by mixed lymphocyte reactions (MLRs); and degree of MHCI expression, quantified by mean fluorescent intensity (MFI); were correlated to the synovial TNCC 24 h after naïve and primed injection. RESULTS: There was a trend of a negative correlation (p = 0.21, r = - 0.44) between TLD score and TNCC after primed injection in the ALLO group. Within the ALLO group only, there was a significant positive correlation (p = 0.05, r = 0.77) between MHCI MFI and TNCC after naïve injection and a trend (p = 0.16, r = 0.49) of a positive association of MHCI MFI to TNCC after primed injection. Within the FBS group only, there was a positive correlation (p = 0.04, r = 1) between TNCC and lymphocyte proliferation after both injections. CONCLUSIONS: The trend of a negative correlation of TLD score and TNCC in the ALLO, but not the FBS group, together with the association of MHCI expression and TNCC in the ALLO group, indicates that improved stemness is associated with reduced MSC immunogenicity. When inflammation was incited by xenogen, there was a strong correlation of lymphocyte activation in vitro to adverse response in vivo, confirming that MLRs in vitro reflect MSC immunomodulatory activity in vivo. The relationship of stemness in vitro, suppression of lymphocyte activation in vitro, MHCI expression in vitro, and clinical response in vivo should be further investigated.