Temporal and histologic relationships of proliferating cell nuclear antigen and human papillomavirus type 11 in the mouse xenograft system

Proliferating cell nuclear antigen (PCNA) is an accessory protein of DNA polymerase delta. This protein is associated with cell cycle progression and can be detected in the replicating cells of normal tissues. Condylomata acuminata are benign epithelial tumors caused by infection with human papillomaviruses and are characterized by abnormal cell proliferation. The athymic mouse xenograft model of HPV 11 infection was used to test the hypothesis that PCNA is induced early in the course of HPV 11 infection and to study the temporal and histologic relationships between detection of PCNA and HPV DNA. Human foreskin tissue was infected with HPV 11 and implanted under the renal capsules of 10 athymic mice. Pairs of mice were sacrificed every week beginning four weeks after implantation. HPV DNA was detected in sections of foreskin implants by in situ hybridization. PCNA was as or more abundant in implants removed at earlier time points than at later time points, whereas HPV DNA became increasingly more abundant with time. PCNA was detected only in basal cells in areas of histologically normal epithelium that were also negative for HPV DNA. In contrast, PCNA was present throughout the epithelium in regions that were HPV DNA-positive. HPV DNA was detected only in differentiated epithelial cells in implants removed at all five time points, but in HPV DNA-positive regions, PCNA was detected with equal intensity in differentiated and undifferentiated cells. The foci of PCNA-positive cells were well demarcated and were larger than, but included, the foci of HPV DNA-positive cells. PCNA may be induced maximally in differentiated epithelium by HPV 11 prior to significant HPV DNA replication. © 1996 Wiley-Liss, Inc.     

The canals of hering might represent a target of methotrexate hepatic toxicity

Methotrexate treatment for psoriasis is known to cause hepatic fibrosis in some patients, which might progress to cirrhosis. The fine, radiating, fibrous septa developing in this setting have a distribution that is reminiscent of the location of the canals of Hering (coH). To assess the possibility of fibrous obliteration of the coH in patients receiving methotrexate, we developed a staining technique by combining an immunohistochemical stain for cytokeratin 7 with a modified Masson trichrome. Sixteen biopsy specimens from 7 patients were evaluated. The biopsies had a variety of histologic changes, including steatosis, anisonucleosis, multinucleation, chronic inflammation, bile duct damage, and ductular reaction. Fibrosis was present in 13 biopsy specimens (81%) and was mild in 7, moderate in 3, and severe in 3 specimens. Compared with normal (control) liver specimens, biopsy specimensfrom patients receiving methotrexate had decreased numbers of coH (1.9 +/- 0.8 vs 5.2 +/- 1.7; P < .025). In specimens with moderate or severe fibrosis, fibrous septa sometimes extended along the coH. These findings suggest that scarring of the coH might be a consequence of the toxic effects of methotrexate.     

Nucleus accumbens acetylcholine regulates appetitive learning and motivation for food via activation of muscarinic receptors

These experiments tested whether nucleus accumbens muscarinic or nicotinic acetylcholine receptor activation is required for rats to learn to lever press for sucrose. Muscarinic blockade with scopolamine (1.0 microg/side or 10.0 microg/side), but not nicotinic antagonism with mecamylamine (10.0 microg/side), inhibited learning and performance when applied to the core or shell. Further experiments showed that acute accumbens scopolamine treatment increased locomotor activity and reduced sucrose consumption. However, microanalyses of behavioral events in the instrumental chamber revealed that reductions of lever press performance during muscarinic blockade were not due to gross motor dysfunction. Accumbens core scopolamine was subsequently shown to reduce the amount of work rats would expend under a progressive ratio paradigm. These novel results implicate nucleus accumbens muscarinic receptors in the modulation of appetitive learning, performance, and motivation for food.     

The assessment of tubal functional status by tubal perfusion pressure measurements

The measurement of tubal perfusion pressures (TPP) is a recent advance in the field of gynaecoradiology. Measurement of TPP involves a standardized technique using transcervically placed tubal catheters which is reviewed in detail. TPP assesses the functional status of the Fallopian tubes, i.e. their ability to permit pregnancy. Infertile patients with normal TPP demonstrated a higher pregnancy rate (10 out of 23) than patients with elevated TPP (four out of 24, P < 0.05). Analysis of patients who had undergone a laparoscopy as well as measurement of TPP suggest that elevated TPP are highly indicative of tubal endometriosis. Tubal catheterization with wireguides was successful in reducing mildly elevated TPP. The impact of this procedure on pregnancy rates is not known. The use of the gynaecoradiological techniques discussed in this paper has reduced the need for diagnostic laparoscopy at our centre by >60%. This was achieved without compromise in pregnancy rates and has resulted in a considerable reduction in cost.     

Vaccine to confer to nonhuman primates complete protection against multistrain Ebola and Marburg virus infections

Filoviruses (Ebola and Marburg viruses) are among the deadliest viruses known to mankind, with mortality rates nearing 90%. These pathogens are highly infectious through contact with infected body fluids and can be easily aerosolized. Additionally, there are currently no licensed vaccines available to prevent filovirus outbreaks. Their high mortality rates and infectious capabilities when aerosolized and the lack of licensed vaccines available to prevent such infectious make Ebola and Marburg viruses serious bioterrorism threats, placing them both on the category A list of bioterrorism agents. Here we describe a panfilovirus vaccine based on a complex adenovirus (CAdVax) technology that expresses multiple antigens from five different filoviruses de novo. Vaccination of nonhuman primates demonstrated 100% protection against infection by two species of Ebola virus and three Marburg virus subtypes, each administered at 1,000 times the lethal dose. This study indicates the feasibility of vaccination against all current filovirus threats in the event of natural hemorrhagic fever outbreak or biological attack.     

Selective serotonin receptor stimulation of the medial nucleus accumbens differentially affects appetitive motivation for food on a progressive ratio schedule of reinforcement

Previously, we reported that stimulation of selective serotonin (5-HT) receptor subtypes in the nucleus accumbens shell differentially affected consumption of freely available food. Specifically, activation of 5-HT₆ receptors caused a dose-dependent increase in food intake, while the stimulation of 5-HT_1/7 receptor subtypes decreased feeding [34]. The current experiments tested whether similar pharmacological activation of nucleus accumbens serotonin receptors would also affect appetitive motivation, as measured by the amount of effort non-deprived rats exerted to earn sugar reinforcement. Rats were trained to lever press for sugar pellets on a progressive ratio 2 schedule of reinforcement. Across multiple treatment days, three separate groups (N = 8–10) received bilateral infusions of the 5-HT₆ agonist EMD 386088 (at 0.0, 1.0 and 4.0 μg/0.5 μl/side), the 5-HT_1/7 agonist 5-CT (at 0, 0.5, 1.0, or 4.0 μg/0.5 μl/side), or the 5-HT_2C agonist RO 60-0175 fumarate (at 0, 2.0, or 5.0 μg/0.5 μl/side) into the anterior medial nucleus accumbens prior to a 1-h progressive ratio session. Stimulation of 5-HT₆ receptors caused a dose-dependent increase in motivation as assessed by break point, reinforcers earned, and total active lever presses. Stimulation of 5-HT_1/7 receptors increased lever pressing at the 0.5 μg dose of 5-CT, but inhibited lever presses and break point at 4.0 μg/side. Injection of the 5-HT_2C agonist had no effect on motivation within the task. Collectively, these experiments suggest that, in addition to their role in modulating food consumption, nucleus accumbens 5-HT₆ and 5-HT_1/7 receptors also differentially regulate the appetitive components of food-directed motivation.     

Attribution of menopause symptoms in human immunodeficiency virus-infected or at-risk drug-using women

OBJECTIVE: To examine the relationship of human immunodeficiency virus (HIV) and attribution of menopausal symptoms. DESIGN: Peri- and postmenopausal women participating in a prospective study of HIV-infected and at-risk midlife women (the Ms. Study) were interviewed to determine whether they experienced hot flashes and/or vaginal dryness and to what they attributed these symptoms. RESULTS: Of 278 women, 70% were perimenopausal; 54% were HIV-infected; and 52% had used crack, cocaine, heroin, and/or methadone within the past 5 years. Hot flashes were reported by 189 women and vaginal dryness was reported by 101 women. Overall, 69.8% attributed hot flashes to menopause and 28.7% attributed vaginal dryness to menopause. In bivariate analyses, age 45 years and older was associated with attributing hot flashes and vaginal dryness to menopause, and postmenopausal status and at least 12 years of education were associated with attributing vaginal dryness to menopause, but HIV status was not associated with attribution to menopause. In multivariate analysis, significant interactions between age and menopause status were found for both attribution of hot flashes (P=0.019) and vaginal dryness (P=0.029). Among perimenopausal women, older age was independently associated with attribution to menopause for hot flashes (adjusted odds ratio=1.2, 95% CI: 1.1-1.4, P=0.001) and vaginal dryness (adjusted odds ratio=1.3, 95% CI: 1.1-1.6, P=0.011). None of the tested factors were independently associated with attribution to menopause among postmenopausal women. CONCLUSION: Tailored health education programs may be beneficial in increasing the knowledge about menopause among HIV-infected and drug-using women, particularly those who are perimenopausal.     

Up-regulation of beta-chemokines and down-modulation of CCR5 co-receptors inhibit simian immunodeficiency virus transmission in non-human primates

A non-cognate mechanism of protection against human immunodeficiency virus-1 (HIV-1) infection involves up-regulation of beta-chemokines, which bind and may down-modulate the CCR5 co-receptors, thereby preventing transmission of M-tropic HIV-1. The objective of this investigation was to evaluate this mechanism in vivo in non-human primates. Rhesus macaques were immunized by a modified targeted lymph nodes (TLN) route with recombinant simian immunodeficiency virus (SIV) glycoprotein 120 (gp120) and p27 in alum, and adsorbed recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) with either interleukin (IL)-2 or IL-4. Immunization induced significant increases in the concentrations of CD8 cell-derived suppressor factor (CD8-SF), regulated on activation normal T cells expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1alpha and MIP-1beta, and down-modulation of the proportion of cells expressing CCR5 (r = 0.737, P<0.05). The macaques were then challenged with SIVmac 220 by the rectal mucosal route. The plasma SIVmac RNA showed a significant inverse correlation with the CD8-SF or the concentration of the three beta-chemokines (r = 0.831 and 0.824, P<0.01), but a positive correlation between the proportion of CCR5+ cells and SIVmac RNA (r = 0.613, P = 0.05). These results demonstrate for the first time in vivo that immunization up-regulates beta-chemokines, which may down-modulate CCR5 co-receptors, and both functions are significantly correlated with the viral load. Hence, the non-cognate beta-chemokine-CCR5 mechanism should be considered as complementary to specific immunity in vaccination against HIV.