Antiproliferative effects of low-dose micronized progesterone.

OBJECTIVE: To study the pharmacodynamic effects of oral micronized P on endometrial maturation. DESIGN: This was a controlled, open, parallel group, pilot study. SETTING: The experiment was performed in an outpatient academic clinical research unit. PATIENTS: Twelve healthy, P-challenged, estrogen-primed, postmenopausal women participated in the study. INTERVENTIONS: Patients were given 300 mg micronized P daily (8:00 A.M.) or twice (8:00 A.M. and 4:00 P.M.) daily from study days 1 through 14 after estrogen priming for 30 days. Blood samples were taken at 0, 0.5, 1, 1.5, 2, 3, 4, 6, and 8 hours after the 8:00 A.M. dose on study day 1 and 14 and again at 8:00 and 9:30 A.M. on days 3 and 5 fasting, days 7 and 9 after a fatty meal, and day 11 after a high fiber meal. Endometrial biopsies were taken on day 1 and 14. MAIN OUTCOME MEASURES: Progesterone concentrations were measured. Endometrial biopsies were studied for effects on histology, glycogen content of glands, ribosomal RNA, and nuclear estrogen receptors in glands, surface epithelium, and stroma. RESULTS: Day 1 and 14 P kinetics were similar for 8 hours. Dose-dependent increases in glandular glycogen, decrease in ribosomal RNA, and decrease in nuclear estrogen receptors were demonstrated. CONCLUSIONS: Oral micronized P can induce antiproliferative changes in the human endometrium at doses lower than those required for transformation of the endometrium to a full secretory state.

Pharmacokinetics of a single dose of buccal testosterone.

The bioavailability, pharmacokinetics, and metabolism of a novel transbuccal delivery system of testosterone was investigated in five healthy eugonadal men. Total serum testosterone (T), dihydrotestosterone (DHT), and sex hormone-binding globulin (SHBG) concentrations were determined from blood samples obtained at 8:00 a.m. (zero hour), and 30 min and 1, 2, 3, 4, 6, 12 and 24 hours later on day 1, and again on day 2, after dosing. This single transbuccal administration of Buccal T induced a prompt rise in serum T and DHT concentrations. The maximal concentration (Cmax) of T was 19.56 7.64 ng/mL (mean +/- SD; 5.3-fold increase from the baseline) at< 30 min (Tmax) after administration. The elimination half-life of Buccal T was about 1.75 h. Serum DHT peaked at 1 h at a concentration of 1.46 +/- 0.46 ng/mL (2.3-fold increase from the baseline). The drug was well tolerated. This study suggests that the Buccal T is a promising delivery system for natural T.

Initial and steady-state pharmacokinetics of a vaginally administered formulation of progesterone.

OBJECTIVE: The pharmacokinetics of a 100 mg vaginal progesterone suppository was evaluated on days 1 and 7 and a 200 mg suppository on day 14. All the volunteers were given oral 17 beta-estradiol during the study. STUDY DESIGN: Ten postmenopausal women volunteered for this study. Progesterone was given as a vaginal suppository. Peripheral venous samples were obtained at appropriate intervals and analyzed for 17 beta-estradiol and progesterone levels. Area under the curve for progesterone was assessed by the trapezoidal method. Statistical analysis was performed by a one-way analysis of variance. RESULTS: Serum 17 beta-estradiol levels ranged from 22 to 182 pg/ml. Maximal serum progesterone levels ranged from 5.7 to 20.9 ng/ml, with the mean maximal levels 13.97, 16.09, and 12.68 ng/ml (not significantly different) and a mean area under the curve of 168.13, 207.64 and 227.71 ng/ml per hour on days 1, 7, and 14 (not statistically different). CONCLUSIONS: These data indicate that vaginal absorption of progesterone is efficient. The lack of difference in the area under the curve for both doses suggests that the vaginal mucosa or the total surface area of the vagina may limit the absorption of progesterone from the vagina.

The bond strength of Panavia Ex to air-abraded amalgam.

The tensile bond strengths of a resin cement, Panavia Ex, to a spherical and an admixed amalgam were measured after surface treatment with different aluminum oxide abrasive spray procedures. The type of amalgam and the brand of aluminum oxide affected the bond strength of the resin to amalgam alloy. When the spherical alloy was air abraded using 60-microns aluminum oxide prior to cementation of a Rexillium rod using Panavia, the bond strength was not significantly different from the previously reported bond strengths of Panavia to etched enamel. Significantly lower bond strengths were obtained between Panavia and the admixed amalgam alloy. These results suggest that it may be possible to place a resin-bonded prosthesis on an abutment tooth that has been restored using a spherical amalgam alloy.

PA Patch--a new patch testing device. Preliminary report.

The PA Patch, a new multiple-antigen, predispensed patch testing device, was compared to the Finn Chamber in subjects with previous positive patch tests. After pressing the PA Patch well, the PA Patch performed as well as the Finn Chamber in nine subjects tested.

Silver-coated nylon fiber as an antibacterial agent.

A blend of nylon fiber and silver-coated nylon fiber (the latter known as X-static) was used in these experiments. This fiber was bactericidal when bacteria were exposed to it directly or to an extract derived from its prior incubation in salt solution. At ambient temperatures, a rapid exponential decrease of survival occurred, usually after a delay of approximately 1 h. The rate of killing (decrease of survival) increased with an increase in X-static percentage of the fiber blend, temperature of fiber extraction, concentration of Tris buffer present during extraction, and temperature at which bacteria were exposed to the extract. When bacteria were exposed to the extract at 37 degrees C as opposed to ambient temperature, there was no delay in onset of killing. Escherichia coli was generally the indicator organism tested, but comparable results were also found for Pseudomonas, Klebsiella, Staphylococcus, and Streptococcus species. The rate of killing increased with increasing silver ion concentration of the fiber extract, as determined through atomic absorption spectrophotometry. The rate of killing was greater and the onset was earlier with an extract containing silver ions from fiber than with a salt solution containing the same concentration of silver ions from silver nitrate. Studies of the kinetics of ion release suggested that X-static may be an effective, sustained-release antibacterial agent.

Genome locations of temperature-sensitive mutants in glycoprotein gB of herpes simplex virus type 1.

A plasmid containing a herpes simplex virus type 1 (HSV-1) insert from strain KOS, prototypic coordinates 0.345 to 0.368 (3.45 kilobases) was mutagenized in vitro, and potential mutations were introduced into intact viral DNA by cotransfection. Functions normally associated with the glycoprotein gB are in the 1-9 complementation group, and the above coordinates include those that specify the gB glycoprotein gene. Following cotransfection, individual plaques were screened for temperature sensitivity (ts) of viral growth. A total of seven ts mutants was obtained, of which four were spurious mutations due to alterations outside the cloned sequences, presumably mediated by some aspect of the Ca-precipitation-cotransfection method. The remaining three did not complement known mutants of the 1-9 complementation group. These three mutants, along with tsJ12 (P.A. Schaffer, G.M. Aron, N. Biswal, and M. Benyesh-Melnick, 1973, Virology 52, 57-71) and tsJ33 (C.-T. Chu, D.S. Parris, R.A.F. Dixon, F.E. Farber, and P.A. Schaffer, 1979, Virology 98, 168-181), were physically located by marker-rescue experiments to three different restriction fragments between 0.345 to 0.368 map units. Sodium dodecyl sulfate-gel electrophoresis was used to analyze the glycoproteins synthesized during continuous or pulse-chase labeling protocols. All five mutants were found to synthesize a precursor of gB but did not accumulate mature gB during a pulse, a chase, or continuous labeling at the nonpermissive temperature.

Early events in herpes simplex virus type 1 infection: photosensitivity of fluorescein isothiocyanate-treated virions.

Herpes simplex virus type 1 is photosensitized by treatment with fluorescein isothiocyante (FITC). The inactivation of FITC-treated virions upon subsequent exposure to light is inhibited by the presence of sodium azide, suggesting the involvement of singlet oxygen in the process. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis revealed that treatment with FITC plus light induces crosslinks in viral envelope glycoproteins. Treatment of virions with high concentrations of FITC (50 micrograms/ml) plus light causes a reduction in the adsorption of the virus to monolayers of human embryonic lung cells. For lower concentrations of FITC (10 micrograms/ml) plus light, treated virions adsorb to the host cells, but remain sensitive to light until entry occurs. The loss of light sensitivity coincides with the development of resistance to antibodies. These results are most consistent with a mechanism of entry for herpes simplex virus involving fusion of the viral membrane with the plasma membrane of the host cell.

An assessment of factors influencing flexibility of human fingernails.

A new instrument has been developed and used to determine the effect of various materials on nail flexibility. It repeatedly flexes longitudinal nail sections through 90 degrees and records the number of flexions required to fracture each section. Immersion in water or a phospholipid-water preparation (PLW) greatly increases the flexibility of untreated and lipid extracted nails; immersion in mineral oil does not. Nail flexibility is directly related to the duration of their immersion in water. During water immersion, nail weight increases by 22% of its original weight within 2 h, and then decreases. The rapid increase in nail flexibility during water immersion is related to nail water content. It is possible to prolong the flexibility of previously hydrated nails by the application of PLW or mineral oil. PLW is more effective than water alone in prolonging flexibility of nails extracted with a mixture of acetone, water and acetic acid.

Characteristics of a new bacteriophage, Psp231a, infecting Pseudomonas phaseolicola HB10Y.

Bacteriophage Psp231a infects Pseudomonas phaseolicola, strain HB10Y, which is the host cell for the enveloped bacteriophage phi 6. This paper describes the biophysical characteristics of Psp231a and the physical properties of its nucleic acid. In electron micrographs the virion appears as an icosahedral structure, approximately 55 nm in diameter, with a short tail. The virion density is 1.48 g/cm3 in CsCl, and the sedimentation coefficient is approximately 407S. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of 12 polypeptides ranging in molecular weight from 5,000 to 117,000. The nucleic acid of Psp231a is linear, double-stranded DNA of molecular weight 28 X 10(6). Its density in CsCl is 1.716 g/cm3, and its sedimentation coefficient in 3 M CsCl is 20.0S, corresponding to an S020,W of 34S.

Interaction of divalent cations and proteins with phospholipid vesicles.

The broadening of spin-label absorption lines resulting from spin-exchange reactions that occur during collision with paramagnetic Ni2+ is diminished when Ni2+ binds to phospholipid vesicles. Subsequent addition of non-paramagnetic ions that compete for binding sites releases Ni2+ into solution and restores the line-broadening. The concentrations of various ions required to achieve this effect was used to order the ions with respect to their binding to vesicles containing phosphatidylethanolamine and phosphatidylglycerol. The relative strengths of binding for those ions studied were: Ca2+ > Mg2+ > Zn2+ > Sr2+ > Ba2+. The spin-broadening assay was also used to study the effects of two proteins on the availability of Ni2+-binding sites on the vesicles. Ribonuclease, which is thought to associate electrostatically as an extrinsic protein on the surface of vesicles, completely blocked the Ni2+-binding sites at comparatively low protein concentrations. Quantitative considerations of these data suggest the possibility that Ni2+ may bind preferenetially to phosphatidylglycerol, and that these binding sites are aggregated in the ribonuclease-containing vesicles. In contract to ribonuclease, cytochrome c does not block Ni2+-bindings sites on the phospholipid vesicles, but rather contains sites of its own that bind Ni2+, both when the protein is in solution and when it is associated with the vesicles. These results are consistent with other studies which suggest that cytochrome c becomes partially embedded in membrane bilayers and associates with phospholipid molecules through hydrophobic interactions.

A comparison of herpes simplex virus plaque development after viral treatment with anti-DNA or antilipid agents.

The plaque development of Herpes simplex virus type 1 (HSV) is slower for viruses treated with two anti-DNA agents: ultraviolet radiation (UV) or n-acetoxy-2-acetyl-aminofluorene. For HSV treated with three antimembrane agents--butylated hydroxytoluene, acridine plus near UV radiation, or ether--the plaque development time is the same as for untreated viruses. These differences hold even for viruses that survived treatment that lowered viability below the 1% level. Gamma ray inactivation of HSV produces no change in plaque development even though this agent is believed to preferentially affect viral DNA.