Cystic Calculus in a Laboratory-housed Green Anole (Anolis carolinensis).

An adult, male, wild-caught, laboratory-housed green anole (Anolis carolinensis) on a locomotor performance study was presented for anorexia. The anole exhibited a 26% weight loss and a thin body condition but was otherwise alert and active. Despite supportive care, the anole's clinical condition deteriorated, necessitating euthanasia. Postmortem examination revealed a 4.5 mm × 2.5-mm cystic calculus, which consisted entirely of sodium urate. Here we describe the clinical findings and locomotor consequences of this disease in a green anole. Although urolithiasis has been reported clinically in reptiles, this report presents the first case of a cystic calculus in a laboratory-housed green anole.

Characterization of the Genital Microenvironment of Female Rhesus Macaques Prior to and After SIV Infection.

PROBLEM: HIV infection among women is frequently modeled in female rhesus macaques. Longitudinal studies on genital compartment and hormonal factors that can influence susceptibility to SIV infection are lacking in this animal model. METHOD OF STUDY: Genital specimens and menstruation of indoor-housed female rhesus macaques were analyzed prior to and after SIV infection. RESULTS: Median menstrual cycle length averaged 27 days, although highly variable cycle lengths and frequent periods of amenorrhea were observed during summer months. The vaginal microbiota, characterized by adapted Nugent scoring, showed predominance of small Gram-variable rods and Gram-positive cocci. Highly variable vaginal cytokine levels were observed pre- and post-SIV infection. Vaginal viral loads correlated with plasma viral loads, but were not associated with progesterone levels. CONCLUSION: These results provide an integrated characterization of important factors in the vaginal microenvironment that are relevant to the experimental design of HIV prevention and transmission studies in female rhesus macaques.

Chronic Δ9-tetrahydrocannabinol administration may not attenuate simian immunodeficiency virus disease progression in female rhesus macaques.

Persons living with HIV/AIDS (PLWHA) frequently use cannabinoids, either recreationally by smoking marijuana or therapeutically (delta-9-tetrahydrocannabinol; Δ(9)-THC dronabinol). Previously, we demonstrated that chronic Δ(9)-THC administration decreases early mortality in male simian immunodeficiency virus (SIV)-infected macaques. In this study, we sought to examine whether similar protective effects resulted from chronic cannabinoid administration in SIV-infected female rhesus macaques. Clinical and viral parameters were evaluated in eight female rhesus macaques that received either Δ(9)-THC (0.18-0.32 mg/kg, intramuscularly, twice daily) or vehicle (VEH) starting 28 days prior to intravenous inoculation with SIVmac251. SIV disease progression was assessed by changes in body weight, mortality, viral levels in plasma and mucosal sites, and lymphocyte subsets. In contrast to our results in male animals, chronic Δ(9)-THC did not protect SIV-infected female rhesus macaques from early mortality. Markers of SIV disease, including viral load and CD4(+)/CD8(+) ratio, were not altered by Δ(9)-THC compared to control females; however, females that received chronic Δ(9)-THC did not gain as much weight as control animals. In addition, Δ(9)-THC administration increased total CXCR4 expression in both peripheral and duodenal CD4(+) and CD8(+) T lymphocytes prior to SIV inoculation. Although protection from early mortality was not evident, chronic Δ(9)-THC did not affect clinical markers of SIV disease progression. The contrasting effects of chronic Δ(9)-THC in males versus females remain to be explained, but highlight the need for further studies to explore the sex-dependent effects of Δ(9)-THC and other cannabinoids on the HIV disease course and their implications for virus transmission.

Hepatitis E antibodies in laboratory rabbits from 2 US vendors.

We tested laboratory rabbits from 2 US vendors for antibodies against hepatitis E virus (HEV); Seroprevalences were 40% and 50%. Retrospective analysis of an ocular herpes simplex 1 experiment demonstrated that HEV seropositivity had no effect on experiment outcome. HEV probably is widespread in research rabbits, but effects on research remain unknown.

Modulation of gut-specific mechanisms by chronic δ(9)-tetrahydrocannabinol administration in male rhesus macaques infected with simian immunodeficiency virus: a systems biology analysis.

Our studies have demonstrated that chronic Δ(9)-tetrahydrocannabinol (THC) administration results in a generalized attenuation of viral load and tissue inflammation in simian immunodeficiency virus (SIV)-infected male rhesus macaques. Gut-associated lymphoid tissue is an important site for HIV replication and inflammation that can impact disease progression. We used a systems approach to examine the duodenal immune environment in 4- to 6-year-old male rhesus monkeys inoculated intravenously with SIVMAC251 after 17 months of chronic THC administration (0.18-0.32 mg/kg, intramuscularly, twice daily). Duodenal tissue samples excised from chronic THC- (N=4) and vehicle (VEH)-treated (N=4) subjects at ∼5 months postinoculation showed lower viral load, increased duodenal integrin beta 7(+)(ß7) CD4(+) and CD8(+) central memory T cells, and a significant preferential increase in Th2 cytokine expression. Gene array analysis identified six genes that were differentially expressed in intestinal samples of the THC/SIV animals when compared to those differentially expressed between VEH/SIV and uninfected controls. These genes were identified as having significant participation in (1) apoptosis, (2) cell survival, proliferation, and morphogenesis, and (3) energy and substrate metabolic processes. Additional analysis comparing the duodenal gene expression in THC/SIV vs. VEH/SIV animals identified 93 differentially expressed genes that participate in processes involved in muscle contraction, protein folding, cytoskeleton remodeling, cell adhesion, and cell signaling. Immunohistochemical staining showed attenuated apoptosis in epithelial crypt cells of THC/SIV subjects. Our results indicate that chronic THC administration modulated duodenal T cell populations, favored a pro-Th2 cytokine balance, and decreased intestinal apoptosis. These findings reveal novel mechanisms that may potentially contribute to cannabinoid-mediated disease modulation.

Tolerance to chronic delta-9-tetrahydrocannabinol (Δ9-THC) in rhesus macaques infected with simian immunodeficiency virus.

Although Δ9-THC has been approved to treat anorexia and weight loss associated with AIDS, it may also reduce well-being by disrupting complex behavioral processes or enhancing HIV replication. To investigate these possibilities, four groups of male rhesus macaques were trained to respond under an operant acquisition and performance procedure, and administered vehicle or Δ9-THC before and after inoculation with simian immunodeficiency virus (SIV(mac251), 100 TCID50/ml, i.v.). Prior to chronic Δ9-THC and SIV inoculation, 0.032-0.32 mg/kg of Δ9-THC produced dose-dependent rate-decreasing effects and small, sporadic error-increasing effects in the acquisition and performance components in each subject. Following 28 days of chronic Δ9-THC (0.32 mg/kg, i.m.) or vehicle twice daily, delta-9-THC-treated subjects developed tolerance to the rate-decreasing effects, and this tolerance was maintained during the initial 7-12 months irrespective of SIV infection (i.e., +THC/-SIV, +THC/+SIV). Full necropsy was performed on all SIV subjects an average of 329 days post-SIV inoculation, with postmortem histopathology suggestive of a reduced frequency of CNS pathology as well as opportunistic infections in delta-9-THC-treated subjects. Chronic Δ9-THC also significantly reduced CB-1 and CB-2 receptor levels in the hippocampus, attenuated the expression of a proinflammatory cytokine (MCP-1), and did not increase viral load in plasma, cerebrospinal fluid, or brain tissue compared to vehicle-treated subjects with SIV. Together, these data indicate that chronic Δ9-THC produces tolerance to its behaviorally disruptive effects on complex tasks while not adversely affecting viral load or other markers of disease progression during the early stages of infection.

Cannabinoid administration attenuates the progression of simian immunodeficiency virus.

Δ(9)-Tetrahydrocannabinol (Δ(9)-THC), the primary psychoactive component in marijuana, is FDA approved to ameliorate AIDS-associated wasting. Because cannabinoid receptors are expressed on cells of the immune system, chronic Δ(9)-THC use may impact HIV disease progression. We examined the impact of chronic Δ(9)-THC administration (0.32 mg/kg im, 2 × daily), starting 28 days prior to inoculation with simian immunodeficiency virus (SIV(mac251); 100 TCID(50)/ml, iv), on immune and metabolic indicators of disease during the initial 6 month asymptomatic phase of infection in rhesus macaques. SIV(mac251) inoculation resulted in measurable viral load, decreased lymphocyte CD4(+)/CD8(+) ratio, and increased CD8(+) proliferation. Δ(9)-THC treatment of SIV-infected animals produced minor to no effects in these parameters. However, chronic Δ(9)-THC administration decreased early mortality from SIV infection (p = 0.039), and this was associated with attenuation of plasma and CSF viral load and retention of body mass (p = NS). In vitro, Δ(9)-THC (10 µm) decreased SIV (10 TCID(50)) viral replication in MT4-R5 cells. These results indicate that chronic Δ(9)-THC does not increase viral load or aggravate morbidity and may actually ameliorate SIV disease progression. We speculate that reduced levels of SIV, retention of body mass, and attenuation of inflammation are likely mechanisms for Δ(9)-THC-mediated modulation of disease progression that warrant further study.

Comparison of selamectin and imidacloprid plus permethrin in eliminating Leporacarus gibbus infestation in laboratory rabbits (Oryctolagus cuniculus).

A shipment of New Zealand white rabbits was infested with Leporacarus gibbus, a rabbit fur mite. This study compared the effectiveness of selamectin with that of imidocloprid plus permethrin in eliminating the mite infestation. Rabbits were divided into 2 groups, and either selamectin or imidocloprid plus permethrin was applied topically. Visual and microscopic examinations were performed on days 0, 1, 2, 3, 4, 5, 6, 13, and 27 for 5 sites (the left and right gluteal areas, neck, ventral tail, and abdomen). Mean percentage effectiveness for each treatment was calculated for each time point. Positive and negative predictive value, sensitivity, and specificity of visual examination were determined relative to microscopic assessment. In addition, location prevalence for the mites was determined. Both treatments were 100% effective by day 13, but selamectin was 100% effective by day 3. The positive predictive value of visual examination was 96%, its negative predictive value was 86%, sensitivity was 75%, and specificity was 98%. Parasite burden was most prevalent on the right and left gluteal areas. We conclude that although both imidocloprid plus permethrin and selamectin were effective against L. gibbus, treatment with selamectin more rapidly eliminated the infestation.