HIV-1 production from infected peripheral blood T cells after HTLV-I induced mitogenic stimulation

The human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus type I (HTLV-I) are two distinct human retroviruses that infect T cells. Recent epidemiologic studies have identified a cohort of individuals that are coinfected with both viruses. It is reported here that human peripheral blood leukocytes infected with HIV-1 in vitro can be induced to produce large quantities of HIV-1 after mitogenic stimulation by noninfectious HTLV-I virions. It is also shown that HTLV-I virions may exert this effect prior to, immediately following, or well after the cells are infected with HIV-1. These results provide further impetus for epidemiologic studies of dually infected individuals to determine whether HTLV-I may act as a cofactor for acquired immunodeficiency syndrome (AIDS).     

High rate of HTLV-II infection in seropositive i.v. drug abusers in New Orleans

Confirmed infection with HTLV-II (human T cell leukemia virus type II) has been described only in rare cases. The major limitation to serological diagnosis of HTLV-II has been the difficulty of distinguishing HTLV-II from HTLV-I (human T cell leukemia virus type I) infection, because of substantial cross-reactivity between the viruses. A sensitive modification of the polymerase chain reaction method was used to provide unambiguous molecular evidence that a significant proportion of intravenous drug abusers are infected with HTLV, and the majority of these individuals are infected with HTLV-II rather than HTLV-I. Of 23 individuals confirmed by polymerase chain reaction analysis to be infected with HTLV, 21 were identified to be infected with HTLV-II, and 2 were infected with HTLV-I. Molecular identification of an HTLV-II--infected population provides an opportunity to investigate the pathogenicity of HTLV-II in humans.     

A Comparison of Spectrophotometric and Gas Chromatographic Measurements of Heavy Petroleum Products in Soil Samples

Laboratory studies were conducted to compare the infrared spectrophotometry (TPH-IR) and gas chromatography (TPH-GC) measurements of total petroleum hydrocarbon in soil samples.Real world soil samples containing #2 to #6 fuel oils, mechanical lubricating oil, diesel fuel, kerosene, jet fuel andweathered gasoline were extracted with trichlorotrifluoroethane(Freon-113) and methylene chloride. The extractants were analyzed using gas chromatography with flame ionization detection (GC-FID) and infrared spectroscopy (TPH-IR) methods.A paired statistical t-test was applied to compare the average of paired differences in the analytical results. Statistical tests were evaluated with graphical presentation of the results. In general, a trend was observed in the measured concentrations.Total petroleum hydrocarbon (TPH) concentrations measured withTPH-IR had the highest readings. The same samples extracted withmethylene chloride and analyzed with GC-FID showed lower concentrations than the TPH-IR method while the GC-FID analysisof the same samples extracted with Freon-113 produced the lowestconcentrations. Laboratory experiments indicated that TPH concentrations measured with the TPH-IR method were higher thanthe actual quantities of petroleum hydrocarbon in the soil samples.     

SURVIVAL TIMES FOR CANINE INTRANASAL SARCOMAS TREATED WITH RADIATION THERAPY: 86 CASES (1996–2011)

Sarcomas comprise approximately one‐third of canine intranasal tumors, however few veterinary studies have described survival times of dogs with histologic subtypes of sarcomas separately from other intranasal tumors. One objective of this study was to describe median survival times for dogs treated with radiation therapy for intranasal sarcomas. A second objective was to compare survival times for dogs treated with three radiation therapy protocols: daily‐fractionated radiation therapy; Monday, Wednesday, and Friday fractionated radiation therapy; and palliative radiation therapy. Medical records were retrospectively reviewed for dogs that had been treated with radiation therapy for confirmed intranasal sarcoma. A total of 86 dogs met inclusion criteria. Overall median survival time for included dogs was 444 days. Median survival time for dogs with chondrosarcoma (n = 42) was 463 days, fibrosarcoma (n = 12) 379 days, osteosarcoma (n = 6) 624 days, and undifferentiated sarcoma (n = 22) 344 days. Dogs treated with daily‐fractionated radiation therapy protocols; Monday, Wednesday and Friday fractionated radiation therapy protocols; and palliative radiation therapy protocols had median survival times of 641, 347, and 305 days, respectively. A significant difference in survival time was found for dogs receiving curative intent radiation therapy vs. palliative radiation therapy (P = 0.032). A significant difference in survival time was also found for dogs receiving daily‐fractionated radiation therapy vs. Monday, Wednesday and Friday fractionated radiation therapy (P = 0.0134). Findings from this study support the use of curative intent radiation therapy for dogs with intranasal sarcoma. Future prospective, randomized trials are needed for confirmation of treatment benefits.     

Interleukin-1beta and tumor necrosis factor-alpha produce distinct, time-dependent patterns of acute arthritis in the rat knee

Interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) synergistically induce and sustain arthritis. Two competing hypotheses of arthritis induction are 1) that TNF preferentially mediates inflammation, whereas IL-1 impels bone destruction, or 2) that either cytokine controls the entire process. In this study, these propositions were tested in two experiments by instilling IL-1beta or TNF-alpha into one knee of Lewis rats (n = 6/group) to incite arthritis, after which semiquantitative scores for inflammation, bone resorption, osteoclasts, and cartilage integrity were acquired. In the induction study, IL-1beta or TNF-alpha (3, 10, or 30 micro g) was given once to incite arthritis. After 2 days, IL-1beta induced significant, dose-dependent increases in inflammation (mild to marked), bone resorption (minimal to moderate), and osteoclasts (minimal to moderate). In contrast, TNF-alpha induced minimal to mild inflammation but had little impact on resorption or osteoclasts. Both IL-1 and TNF (>/=10 micro g) yielded mild cartilage degeneration. Most lesion scores in TNF-treated rats were significantly lower than those in animals given the same dose of IL-1beta. In the persistence study, rats were injected once with IL-1 or TNF (10 micro g) and maintained for 2, 3, or 7 days. IL-1beta significantly enhanced inflammation (all 3 days), bone resorption (days 2 and 3), osteoclasts (days 2 and 3), and cartilage matrix loss (days 2 and 3), whereas TNF-alpha augmented inflammation (days 2 and 3) and cartilage degeneration (day 2) but not bone resorption or osteoclasts. Thus, both IL-1beta and TNF-alpha can launch inflammation, but IL-1beta drives skeletal destruction.     

Biological effects of staphylococcal protein A immunotherapy in cats with induced feline leukemia virus infection.

Biological effects of staphylococcal protein A (SPA) immunotherapy were studied in 5 viremic and 6 nonviremic cats with induced FeLV infection and in 6 control cats. The SPA therapy neither reversed FeLV viremia nor resulted in consistent improvement in humoral immune responses to FeLV antigens. However, SPA immunotherapy induced a proliferative response in bone marrow granulocytic lineage, possibly resulting in expression of FeLV-free mature neutrophils in the blood. Seemingly, viral burden and chemiluminescent responses were reversed in viremic cats during SPA immunotherapy.