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Vaginal rapidly disintegrating tablets (RDTs) containing tenofovir (TFV) or TFV and emtricitabine (FTC) were evaluated for safety and pharmacokinetics in pigtailed macaques. Two separate animal groups ( n = 4) received TFV (10 mg) or TFV-FTC (10 mg each) RDTs, administered near the cervix. A third group ( n = 4) received 1 ml TFV gel. Blood plasma, vaginal tissue biopsy specimens, and vaginal fluids were collected before and after product application at 0, 0.5, 1, 4, and 24 h. A disintegration time of 4 to 10 5 ng/g (147 to 571 μM) and 10 6 ng/g (12 to 34 mM), respectively, at 1 to 4 h postdose. At 24 h, however, TFV vaginal tissue levels were more sustained after RDT dosing, with median TFV concentrations being approximately 1 log higher than those with gel dosing. FTC pharmacokinetics after combination RDT dosing were similar to those of TFV, with peak median vaginal tissue and fluid levels being on the order of 10 4 ng/g (374 μM) and 10 6 ng/g (32 mM), respectively, at 1 h postdose with levels in fluid remaining high at 24 h. RDTs are a promising alternative vaginal dosage form, delivering TFV and/or FTC at levels that would be considered inhibitory to simian-human immunodeficiency virus in the macaque vaginal microenvironment over a 24-h period.

A herpes simplex virus (HSV) vector in which the mammalian promoter for neuron-specific enolase (NSE) controls expression of a marker gene was analyzed for its ability to drive expression of this foreign gene in culture and in vivo. In cultured cells, the vector appeared to give neuron-specific expression. Introduction of 10(6) pfu of the virus into the adult rat caudate nucleus by stereotactic injection was not toxic to the animals and yielded beta-galactosidase (beta-gal)-positive neurons for at least 30 days after viral inoculation. This recombinant herpes virus vector is the first described to use a mammalian promoter to yield extended expression of a foreign gene product in the adult mammalian central nervous system (CNS).

While modified vaccinia virus Ankara (MVA) is currently in clinical development as a safe vaccine against smallpox and heterologous infectious diseases, its immunogenicity is likely limited due to the inability of the virus to replicate productively in mammalian hosts. In light of recent data demonstrating that vaccinia viruses, including MVA, preferentially infect antigen-presenting cells (APCs) that play crucial roles in generating antiviral immunity, we hypothesized that expression of specific cytokines and chemokines that mediate APC recruitment and activation from recombinant MVA (rMVA) vectors would enhance the immunogenicity of these vectors. To test this hypothesis, we generated rMVAs that express murine granulocyte-macrophage colony-stimulating factor (mGM-CSF), human CCL20/human macrophage inflammatory protein 3α (hCCL20/hMIP-3α), or human fms-like tyrosine kinase 3 ligand (hFlt3-L), factors predicted to increase levels of dendritic cells (DCs), to recruit DCs to sites of immunization, or to promote maturation of DCs in vivo, respectively. These rMVAs also coexpress the well-characterized, immunodominant lymphocytic choriomeningitis virus nucleoprotein (NP) antigen that enabled sensitive and quantitative assessment of antigen-specific CD8+T-cell responses following immunization of BALB/c mice. Our results demonstrate that immunization of mice with rMVAs expressing mGM-CSF or hCCL20, but not hFlt3-L, results in two- to fourfold increases of cellular immune responses directed against vector-encoded antigens and 6- to 17-fold enhancements of MVA-specific antibody titers, compared to those responses elicited by nonadjuvanted rMVA. Of note, cytokine augmentation of cellular immune responses occurs when rMVAs are given as primary immunizations but not when they are used as booster immunizations, suggesting that these APC-modulating proteins, when used as poxvirus-encoded adjuvants, are more effective at stimulating naïve T-cell responses than in promoting recall of preexisting memory T-cell responses. Our results demonstrate that a strategy to express specific genetic adjuvants from rMVA vectors can be successfully applied to enhance the immunogenicity of MVA-based vaccines.

Successful implant placement at the time of extraction has been documented. Implant placement at the time of extraction was initially performed as a two-stage procedure often with barrier membranes and sophisticated second-stage surgical uncoverings. The authors describe the next generation of this technique, including atraumatic tooth removal with simultaneous root form, implant placement, and temporization at one appointment. This technique of "Immediate Total Tooth Replacement" allows for the maintenance of the bony housing and soft-tissue form that existed before extraction, while at the same time establishing a root form anchor in the bone for an esthetic restoration.

We previously showed 1 that a peptide, Ac-hE18A-NH(2), in which the arginine-rich heparin-binding domain of apolipoprotein E (apoE) [residues 141;-150] (LRKLRKRLLR), covalently linked to 18A (DWLKAFYDKVAEKLKEAF; a class A amphipathic helix with high lipid affinity), enhanced LDL uptake and clearance. Because VLDL and remnants contain more cholesterol per particle than LDL, enhanced hepatic clearance of VLDL could lead to an effective lowering of plasma cholesterol. Therefore, in the present article we compared the ability of this peptide to mediate/facilitate the uptake and degradation of LDL and VLDL in HepG2 cells. The peptide Ac-hE18A-NH(2), but not Ac-18A-NH(2), enhanced the uptake of LDL by HepG2 cells 5-fold and its degradation 2-fold. The association of the peptides with VLDL resulted in the displacement of native apoE; however, only Ac-hE18A-NH(2) but not Ac-18A-NH(2) caused markedly enhanced uptake (6-fold) and degradation (3-fold) of VLDL. Ac-hE18A-NH(2) also enhanced the uptake (15-fold) and degradation (2-fold) of trypsinized VLDL Sf 100;-400 (containing no immuno-detectable apoE), indicating that the peptide restored the cellular interaction of VLDL in the absence of its essential native ligand (apoE). Pretreatment of HepG2s with heparinase and heparitinase abrogated all peptide-mediated enhanced cellular activity, implicating a role for cell-surface heparan sulfate proteoglycans (HSPG). Intravenous administration of Ac-hE18A-NH(2) into apoE gene knockout mice reduced plasma cholesterol by 88% at 6 h and 30% at 24 h after injection. We conclude that this dual-domain peptide associates with LDL and VLDL and results in rapid hepatic uptake via a HSPG-facilitated pathway.

Several synthetic class A peptide analogues have been shown to mimic many of the properties of human apo A-I in vitro. A new peptide [acetyl-(AspTrpLeuLysAlaPheTyrAspLysValPheGluLysPheLysGluPhePhe)-NH2; 5F], with increased amphipathicity, was administered by intraperitoneal injection, 20 microg/day for 16 weeks, to C57BL/6J mice fed an atherogenic diet. Mouse apo A-I (MoA-I) (50 microg/day) or phosphate-buffered saline (PBS) injections were given to other mice as controls. Total plasma cholesterol levels and lipoprotein profiles were not significantly different between the treated and control groups, except that the mice receiving 5F or MoA-I had lower high density lipoprotein (HDL) cholesterol when calculated as a percentage of total cholesterol. No toxicity or production of antibodies to the injected materials was observed. When HDL was isolated from high fat diet-administered mice injected with 5F and presented to human artery wall cells in vitro together with human low density lipoprotein (LDL), there were substantially fewer lipid hydroperoxides formed and substantially less LDL-induced monocyte chemotactic activity than with HDL from PBS-injected animals. Injection of human apo A-I produced effects similar to 5F on lipid peroxide formation and LDL-induced monocyte chemotactic activity, but injection of MoA-I was significantly less effective in reducing lipid hydroperoxide formation or lowering LDL-induced monocyte chemotactic activity. Mice receiving peptide 5F had significantly less aortic atherosclerotic lesion area compared with mice receiving PBS, whereas lesion area in mice receiving MoA-I was similar to that of the PBS-injected animals. This is the first in vivo demonstration that a model class A amphipathic helical peptide has antiatherosclerotic properties. We conclude that 5F inhibits lesion formation in high fat diet-administered mice by a mechanism that does not involve changes in the lipoprotein profile, and may have potential in the prevention and treatment of atherosclerosis.

A simple and convenient method to determine plasma cholesterol profiles in individual mouse plasma samples is not presently available. With commonly used methods, plasma samples from several animals in a study group must often be pooled and analyzed, usually by the fast phase liquid chromatography (FPLC) method. The Column Lipoprotein Profile (or CLiP) method described here is a modification of the FPLC method that provides a simple and convenient procedure for determining plasma lipoprotein cholesterol profiles in small sample volumes, allowing determination of profiles from individual animals rather than from pooled plasma. The CLiP method is reproducible; a human sample measured five times over several days produced coefficients of variation as follows: VLDL, 10.0%; LDL, 0.93%; and HDL, 2.51%. CLiP-derived total cholesterol values of five different human samples (with total cholesterol levels ranging from 198 to 263 mg/dL) differed from VAP-II by -1.88% +/- 2.57%. Linearity of differing concentrations for each of the lipoprotein classes was determined by measuring the same sample with different aliquot sizes. The linear regression from VLDL had an r value of 0.996, while LDL, HDL, and total cholesterol all had r values of greater than 0.999. We present a direct comparison of plasma cholesterol profiles from several mouse models with gene modification or expression of transgenic proteins. In conclusion, the CLiP method provides a simple, reliable, and reproducible procedure for determination of plasma cholesterol profiles from individual plasma samples with very low sample volumes, using readily available equipment and reagents.

Over the last 37 years, crown-lengthening procedures have been used predictably to restore teeth broken down from caries, trauma, and extensive wear. With crown lengthening, the dentogingival junction is "re-created" at a more apical level on the root to accommodate the junctional epithelium and the connective tissue attachment. Forced eruption can be used in addition, or as an alternative, to tooth lengthening. The authors discuss the indications for tooth lengthening, forced eruption, and orthodontic extrusion, as well as the treatment planning for these procedures.

There are many techniques for stabilizing and splinting teeth. No matter which restorative technique is chosen, the technical elements of marginal fit, psychologic contour, cleansibility, and occlusion must be met. When the restoration is in the esthetic zone of the oral cavity, there is an additional element of achieving an acceptable cosmetic result. This article presents an overview of concepts to achieve acceptable esthetic results when teeth are joined together.

Porcelain laminate veneers have exhibited predictability and, as a result, experienced an incredibly rapid public acceptance with widespread utilization. The introduction of a stronger, leucite-reinforced ceramic system which could be accurately pressed (IPS Empress, Ivoclar Williams, Amherst, NY), presented new avenues for this remarkable treatment modality beyond aesthetic enhancement. Porcelain veneer restorations could be utilized to accurately alter and correct occlusal relationships, and the less abrasive surface of the material offered a distinct advantage in occlusal modifications, such as altering cuspal guidance or vertical dimension. This presentation reviews the history of porcelain veneer restoration and outlines the use of a luting cement (Variolink II, Ivoclar Vivadent, Amherst, NY) for its application.

In any restoration or natural tooth, the surrounding soft-tissue profile plays an integral role in the final esthetics of a case. Similarly in implant restorations, it is no longer sufficient to merely attach a prosthetic device to the underlying fixture, but for optimal esthetics it has become essential for the implant site to be reconstituted in a three-dimensional approach. This invariably involves redevelopment or replacement of lost hard tissue and redevelopment of the correct soft-tissue profile, so that the implant can be placed in the desired position as determined by the restoration, while the soft-tissue profiles are in turn generated by the actual form and contours of the prosthetic device. This article addresses an approach to implant site development.

This new, highly sensitive analytical system, based on controlled dispersion of the flowing sample, gives a rapid, continuous, and direct analysis for cholesterol in all lipoprotein classes, separated by single vertical-spin density-gradient ultracentrifugation. In this Vertical Auto Profile-II fingerstick system, designated VAP-IIfs, a narrow-bore Teflon coil serves as the reactor with no segmentation of the analytical stream by air bubbles, in contrast to the Technicon AutoAnalyzer used in the VAP-I method. Concentrations of high-, low-, intermediate-, and very-low-density lipoprotein cholesterol and lipoprotein(a) cholesterol are determined by decomposing the spectrophotometric absorbance curve for the continuous analysis of the centrifuged sample, with use of software developed in this laboratory. Total cholesterol is determined from the total area under the absorbance curve. For assaying total cholesterol, the CV between aliquots within a rotor ranged from 1.35% to 3.15%; the CV between rotors was 2.45%. Because only 18 microL of sample is required, VAP-IIfs can be readily adapted to analysis for lipoprotein cholesterol profiles in capillary blood samples. Total cholesterol values by VAP-IIfs for fingerstick and venous samples from 23 subjects agreed well: slope = 1.01 (SD 0.03), intercept = -21 (SD 51) mg/L, Sy/x = 50 mg/L, and r = 0.992. Results by VAP-IIfs also correlated highly with results for duplicate samples analyzed at the Northwest Lipid Research Laboratories.

Lack of response to a cholesterol-lowering diet can be caused by physiological nonresponsiveness, inadequate knowledge, or inability to change dietary habits (poor compliance). The purpose of this study was to evaluate the dietary compliance of hyperlipidemic individuals who received intensive initial dietary education and followup, and who showed an initial reduction of their plasma cholesterol levels.One hundred five individuals with fasting cholesterol levels of 5.17 mmol/L (200 mg/dL) or greater received intensive education and follow-up on the American Heart Association Step I diet during an initial 12-week period. The participants provided 3-day dietary records every week, and fasting lipoprotein analysis was performed biweekly. Six months after termination of this period, the subjects were requested to return for a follow-up evaluation of their lipoprotein profile and dietary adherence.Seventy-three (70%) of the subjects returned for a follow-up evaluation of lipoprotein cholesterol levels. Of these, 42 (58%) had a 10% or greater average initial decrease in total cholesterol levels at weeks 3 and 4 ("baseline"), and they were considered to be "high responders." At the 6-month follow up, the average plasma cholesterol level in these responders remained 6.4% below that at entry level, but it had increased by 19% compared with baseline values (6.30 mmol/L [244 mg/dL] vs 5.43 mmol/L [210 mg/dL], respectively). Corresponding significant increases at 6 months were found in high-density lipoprotein cholesterol (8%), low-density lipoprotein cholesterol (16%), and very-low-density lipoprotein cholesterol (66%) levels. Analysis of dietary histories revealed that dietary cholesterol and percent calories from fat increased significantly, but remained within the recommended guidelines. However, the increase in percent calories from saturated fat (from 10.0% +/- 0.5% to 14.4% +/- 1.0% [mean +/- SEM]) deviated markedly from these guidelines.The results suggest the long-term compliance to the reduction of dietary saturated fat remains a problem, even in individuals who receive intensive initial training and show an early favorable response. Follow-up evaluation of hyperlipidemic patients who are receiving dietary therapy should take into account this behavioral pattern. It remains to be determined whether continuing supervision and better nutritional labeling will facilitate dietary compliance.

Gene delivery to the adult rodent brain can be achieved using recombinant virus vectors derived from herpes simplex virus type 1 (HSV-1). This double stranded DNA virus has a large genome (150 kb) which may carry up to 50 kb of foreign DNA at replaceable sites. This virus has a number of advantages for delivery of genes to neurons. It can be taken up by nerve terminals and transported by rapid retrograde transport to the cell nucleus; it can be passed transsynaptically between neurons; and it can enter latency in many types of neurons and possibly other cell types. In latency, the virus exists in a stable and essentially benign form in the nucleus, with active transcription predominantly from one viral promoter. Our group and others have generated vectors which are replication-compromised or replication-defective and have diminished pathogenicity to animals. These vectors can confer both short- and long-term expression of foreign genes on neurons in the peripheral and central nervous systems. Examples will be given here for gene delivery to the adult rat nervous system using vectors which lack viral thymidine kinase activity and cannot replicate in neurons, focusing on the use of two non-herpes virus promoters — the Moloney murine leukemia virus (MoMLV) long terminal repeat (LTR) promoter and the rat neuronal specific enolase promoter — to confer expression of the E. coli lacZ gene on neural cells in the brain. Herpes vectors can potentially be used to change the physiology of specific sets of endogenous neurons following stereotactic inoculation into the rat brain. This gene delivery scheme might prove useful in therapeutic paradigms where subsets of neurons need to be reprogrammed to augment their survival or function.

The ion-implantation\char22{}perturbed-angular-correlation technique (IMPACT) has been used to measured the $g$ factor of the 204-keV ${\frac{3}{2}}^{+}$ level in $^{95}\mathrm{Mo}$ nuclei recoiled into ferromagnetic iron and cobalt hosts. The observed angular precessions were $\ensuremath{\omega}\ensuremath{\tau}(Fe \mathrm{Mo})=0.32\ifmmode\pm\else\textpm\fi{}0.05$ and $\ensuremath{\omega}\ensuremath{\tau}(Co \mathrm{Mo})=0.18\ifmmode\pm\else\textpm\fi{}0.03$. The available direct lifetime measurements for the 204-keV states and the NMR hyperfine field measurements for molybdenum solutes in iron and cobalt are used to obtain the gyromagnetic ratio $g(204)=\ensuremath{-}0.24\ifmmode\pm\else\textpm\fi{}0.03$. The sign of the hyperfine field for molybdenum in iron host was found to be negative.

The iron-implantation-perturbed-angular-correlation technique (IMPACT) has been used to measure the Larmor precessions of the 328, 240, and 356 keV states of194Pt,195Pt, and196Pt nuclei, respectively, in ferromagnetic iron and cobalt hosts. The observed angular precessions in iron, corrected for the transient field effect, wereω τ194(328)=0.103±0.006 rad,ω τ195 (240)=0.142±0.012, andω τ196(356)=0.084±0.010. For cobalt hosts, the observed Larmor precessions were ω τ194(328)=0.068±0.006, ω τ195(240)=0.096±0.012, andω τ196(356)=0.057±0.013. Agreement between theg-factors obtained from the measurements in iron hosts and the measurements in cobalt hosts is very good, and a weighted average of the two measurements givesg194(328)=0.349±0.031,g195 (240)=0.136±0.013, andg196(356)=0.329±0.039.

$\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ directional correlation and polarization directional correlation experiments were performed on three cascades in $^{96}\mathrm{Mo}$ populated from $^{96}\mathrm{Tc}$ (4.3 day). Ge(Li) detectors were used in both spectrometers. Combination of the results give unique spin-${4}^{+}$ assignment to the 1628-keV level and spin-${6}^{+}$ assignments to both the 2441- and 2755-keV levels in $^{96}\mathrm{Mo}$.