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The Plantower PMS5003 sensors (PMS) used in the PurpleAir monitor PA-II-SD configuration (PA-PMS) are equivalent to cell-reciprocal nephelometers using a 657 nm perpendicularly polarized light source that integrates light scattering from 18 to 166∘. Yearlong field data at the National Oceanic and Atmospheric Administration's (NOAA) Mauna Loa Observatory (MLO) and Boulder Table Mountain (BOS) sites show that the 1 h average of the PA-PMS first size channel, labeled “> 0.3 µm” (“CH1”), is highly correlated with submicrometer aerosol scattering coefficients at the 550 and 700 nm wavelengths measured by the TSI 3563 integrating nephelometer, from 0.4 to 500 Mm−1. This corresponds to an hourly average submicrometer aerosol mass concentration of approximately 0.2 to 200 µg m−3. A physical–optical model of the PMS is developed to estimate light intensity on the photodiode, accounting for angular truncation of the volume scattering function as a function of particle size. The model predicts that the PMS response to particles > 0.3 µm decreases relative to an ideal nephelometer by about 75 % for particle diameters ≥ 1.0 µm. This is a result of using a laser that is polarized, the angular truncation of the scattered light, and particle losses (e.g., due to aspiration) before reaching the laser. It is shown that CH1 is linearly proportional to the model-predicted intensity of the light scattered by particles in the PMS laser to its photodiode over 4 orders of magnitude. This is consistent with CH1 being a measure of the scattering coefficient and not the particle number concentration or particulate matter concentration. The model predictions are consistent with data from published laboratory studies which evaluated the PMS against a variety of aerosols. Predictions are then compared with yearlong fine aerosol size distribution and scattering coefficient field data at the BOS site. Field data at BOS confirm the model prediction that the ratio of CH1 to the scattering coefficient would be highest for aerosols with median scattering diameters < 0.3 µm. The PMS detects aerosols smaller than 0.3 µm diameter in proportion to their contribution to the scattering coefficient. The results of this study indicate that the PMS is not an optical particle counter and that its six size fractions are not a meaningful representation of particle size distribution. The relationship between the PMS 1 h average CH1 and bsp1, the scattering coefficient in Mm−1 due to particles below 1 µm aerodynamic diameter, at wavelength 550 nm, is found to be bsp1 = 0.015 ± 2.07 × 10−5 × CH1, for relative humidity below 40 %. The coefficient of determination r2 is 0.97. This suggests that the low-cost and widely used PA monitors can be used to measure and predict the submicron aerosol light scattering coefficient in the mid-visible nearly as well as integrating nephelometers. The effectiveness of the PA-PMS to serve as a PM2.5 mass concentration monitor is due to both the sensor behaving like an imperfect integrating nephelometer and the mass scattering efficiency of ambient PM2.5 aerosols being roughly constant.

The aim of this study was to assess the clinical risk of minimal myonecrosis below the cut-off for acute myocardial infarction (MI) in comparison with other grades of acute coronary syndrome (ACS). One-thousand four hundred and sixty seven consecutive patients with ACS admitted between May 2001 and April 2002 were studied in a non-interventional centre. Patients were divided into unstable angina (UA) (cTnT or= 0.1 microg/L) and ST elevation myocardial infarction (STEMI). UA (n = 638) was associated with the fewest events at 6 months (2% cardiac death or MI). Patients with any myonecrosis (n = 829) had worse outcomes (6-month cardiac death or MI 18.3-23.3%). Compared with ACS patients with minimal myonecrosis, UA patients were at significantly lower risk (OR 0.21, 95% CI 0.12-0.45, p < 0.001), NSTEMI patients were at similar risk (OR 1.45, 95% CI 0.89-2.35, p = 0.13), and STEMI patients were at higher risk (OR 2.12 95% CI 1.26-3.85, p = 0.008) in adjusted analyses. Nearly 85% of cardiac deaths occurred within 6 months. The risk of adverse events was higher among patients managed by non-cardiologists (OR 1.66, 95% CI 1-2.75, p = 0.049). Patients with non-ST elevation ACS and minimal myonecrosis are a high-risk group more comparable with NSTEMI and clearly distinguishable from patients with UA.

Hourly-averaged aerosol radiative properties measured over the years 2010–2013 at four continental North American NOAA/ESRL Federated Aerosol Network sites – Southern Great Plains in Lamont, OK (SGP), Bondville, IL (BND), Appalachian State University in Boone, NC (APP), and Egbert, Ontario, Canada (EGB) were analyzed to determine regional variability and temporal variability on several timescales, how this variability has changed over time at the long-term sites (SGP and BND), and whether systematic relationships exist for key aerosol properties relevant to radiative forcing calculations. The aerosol source types influencing the four sites differ enough so as to collectively represent rural, anthropogenically-perturbed air conditions over much of continental North America. Seasonal variability in scattering and absorption coefficients at 550 nm (σsp and σap, respectively) and most aerosol intensive properties was much larger than day of week and diurnal variability at all sites for both the sub-10 μm and sub-1 μm aerosols. Pronounced summer peaks in scattering were observed at all sites, accompanied by broader peaks in absorption, higher single-scattering albedo (ω0), and lower hemispheric backscatter fraction (b). Amplitudes of diurnal and weekly cycles in absorption at the sites were larger for all seasons than those of scattering. The cycle amplitudes of intensive optical properties on these shorter timescales were minimal in most cases. In spite of the high seasonality in ω0 and b, the co-variation of these two intensive properties cause the corresponding seasonal cycle in monthly median direct radiative forcing efficiency to be small, with changes of only a few percent at all sites. Median sub-10 μm aerosol σsp values for SGP and BND for the 2010–2013 time period were ~25% lower for all months than during the late 1990s period studied by Delene and Ogren (2002), consistent with the trends reported in other North American studies. There were even larger reductions in sub-1 μm aerosol σsp, leading to a larger coarse-mode influence at both sites. Similar reductions in median σap were observed at BND but median σsp changed little at SGP relative to the earlier observations of D&O2002, leading to lower ω0 at SGP. Most intensive properties and their variability were similar for both periods but median b was larger for all months of the 2010–2013 period at BND and nearly all months at SGP, indicating a shift toward smaller accumulation-mode particles. Systematic relationships between aerosol radiative properties were developed and applied to provide information on aerosol source types and processes at the four sites but some key relationships varied noticeably with season, indicating that the use of such relationships for model evaluation and inversion of remote sensing data must consider their seasonality.

Aerosol optical properties were measured by the DOE/ARM (US Department of Energy Atmospheric Radiation Measurements) Program Mobile Facility in the framework of the Two-Column Aerosol Project (TCAP) deployed at Cape Cod, Massachusetts, for a~one year period (from summer 2012 to summer 2013). Measured optical properties included aerosol light-absorption coefficient (σap) at low relative humidity (RH) and aerosol light-scattering coefficient (σsp) at low and at RH values varying from 30 to 85%, approximately. Calculated variables included the single scattering albedo (SSA), the scattering Ångström exponent (SAE) and the scattering enhancement factor (f(RH)). Over the period of measurement, f(RH = 80%) had a mean value of 1.9 ± 0.3 and 1.8 ± 0.4 in the PM10 and PM1 fractions, respectively. Higher f(RH = 80%) values were observed for wind directions from 0–180° (marine sector) together with high SSA and low SAE values. The wind sector from 225 to 315° was identified as an anthropogenically-influenced sector, and it was characterized by smaller, darker and less hygroscopic aerosols. For the marine sector, f(RH = 80%) was 2.2 compared with a value of 1.8 obtained for the anthropogenically-influenced sector. The air-mass backward trajectory analysis agreed well with the wind sector analysis. It shows low cluster to cluster variability except for air-masses coming from the Atlantic Ocean that showed higher hygroscopicity. Knowledge of the effect of RH on aerosol optical properties is of great importance for climate forcing calculations and for comparison of in-situ measurements with satellite and remote sensing retrievals. In this sense, predictive capability of f(RH) for use in climate models would be enhanced if other aerosol parameters could be used as proxies to estimate hygroscopic growth. Toward this goal, we propose an exponential equation that successfully estimates aerosol hygroscopicity as a function of SSA at Cape Cod. Further work is needed to determine if the equation obtained is valid in other environments.

In situ analyses with a laser ionization mass spectrometer have shown that a large fraction of aerosols in the bottom few kilometers of the stratosphere contain small amounts of mercury (1). Electron microscopy of particles collected near the tropopause has also detected mercury. The distribution of mercury onto many particles, including those less than 20 nm in diameter, indicates that the mercury is from local condensation of mercury compounds onto particles rather than transport of mercury-rich aerosols from surface sources. Although the results are only semiquantitative, they suggest that most of the mercury in the lower stratosphere is converted into the particulate phase. Mercury-containing particles were present at both middle latitudes and the tropics in two seasons. There is therefore good reason to believe that particulate mercury above the tropopause is global and could affect the atmospheric lifetime of mercury. There are indications that bromine and/ or iodine may be involved in the conversion of mercury from the gas to particle phase. Measurements at altitudes below 5 km did not find mercury in any particles despite sampling some particles that clearly originated in the stratosphere. This indicates that the particulate mercury from the lower stratosphere may be volatile enough to evaporate or decompose once particles reach warmer temperatures.

The aim of this study was to assess the clinical risk of minimal myonecrosis below the cut-off for acute myocardial infarction (MI) in comparison with other grades of acute coronary syndrome (ACS). One-thousand four hundred and sixty seven consecutive patients with ACS admitted between May 2001 and April 2002 were studied in a non-interventional centre. Patients were divided into unstable angina (UA) (cTnT0.01 microg/l), non-ST elevation ACS with minimal myonecrosis (0.01or= cTnT0.1 microg/l), non-ST elevation MI (NSTEMI) (cTnTor= 0.1 microg/L) and ST elevation myocardial infarction (STEMI). UA (n = 638) was associated with the fewest events at 6 months (2% cardiac death or MI). Patients with any myonecrosis (n = 829) had worse outcomes (6-month cardiac death or MI 18.3-23.3%). Compared with ACS patients with minimal myonecrosis, UA patients were at significantly lower risk (OR 0.21, 95% CI 0.12-0.45, p0.001), NSTEMI patients were at similar risk (OR 1.45, 95% CI 0.89-2.35, p = 0.13), and STEMI patients were at higher risk (OR 2.12 95% CI 1.26-3.85, p = 0.008) in adjusted analyses. Nearly 85% of cardiac deaths occurred within 6 months. The risk of adverse events was higher among patients managed by non-cardiologists (OR 1.66, 95% CI 1-2.75, p = 0.049). Patients with non-ST elevation ACS and minimal myonecrosis are a high-risk group more comparable with NSTEMI and clearly distinguishable from patients with UA.

Osseointegrated implants provide predictable restorative support for crowns, restorations, prosthesis abutments, and removable dentures. Their widespread use in recent years has produced different types of complications. Retrograde peri-implantitis, a lesion occurring at the periapical area of an osseointegrated implant, has recently been described. This paper presents a series of reports describing the occurrence and management of retrograde peri-implantitis involving implants replacing teeth with histories of failed endodontic and apicoectomy procedures.

Platelet activation and aggregation are mediated by thrombin cleavage of the exodomain of the PAR1 receptor. The specificity of thrombin for PAR1 is enhanced by binding to a hirudin-like region (Hir) located in the receptor exodomain. Here, we examine the mechanism of thrombin-PAR1 recognition and cleavage by steady-state kinetic measurements using soluble PAR1 N-terminal exodomains. We determined that the primary role of the PAR1 Hir sequence is to reduce the kinetic barriers to formation of the docked thrombin-PAR1 complex rather than to form high affinity ground-state interactions. In addition, the exosite I-bound Hir motif facilitates the productive interaction of the PAR1 (38)LDPR/SFL(44) sequence with the active site of thrombin. This locking process is the most energetically unfavorable step of the overall reaction. The subsequent irreversible steps of peptide bond cleavage are rapid and allosterically enhanced by the presence of the docked Hir sequence. Furthermore, the C-terminal exodomain product of thrombin cleavage, corresponding to the activated receptor, binds tightly to thrombin. This would suggest that an additional role of the Hir sequence in the thrombin-activated receptor is to sequester thrombin to the platelet surface and modulate cleavage of other platelet receptors such as the PAR4 thrombin receptor, which lacks a functional Hir sequence.

Signal transfer between the protease-activated PAR1 thrombin receptor and membrane-associated heterotrimeric G proteins is mediated by protein-protein interactions. We constructed a yeast signaling system that resolves domain-specific functions of binding from coupling in the Galpha subunit. The endogenous yeast Galpha subunit, Gpa1, does not bind to PAR1 and served as a null structural template. N- and C-terminal portions of mammalian G(i2) and G(16) were substituted back into the Gpa1 template and gain-of-function assessed. The C-terminal third of G(16), but not of G(i2), provides sufficient interactions for coupling to occur with PAR1. The N-terminal two-thirds of G(i2) also contains sufficient determinants to bind and couple to PAR1 and overcome the otherwise negative or missing interactions supplied by the C-terminal third of Gpa1. Replacement of the N-terminal alpha-helix of G(i2), residues 1-34, with those of Gpa1 abolishes coupling but not binding to PAR1 or to betagamma subunits. These data support a model that the N-terminal alphaN helix of the Galpha subunit is physically interposed between PAR1 and the Gbeta subunit and directly assists in transferring the signal between agonist-activated receptor and G protein.

Three postgraduate prosthodontic students served as clinicians/evaluators in a study rating their preferences for three different diamond cutting instruments from three manufacturers. Each evaluator prepared the axial walls of complete veneer crowns on extracted molar teeth and then ranked their preference of the instruments. To prepare nine teeth, each of the three instruments was used in random order and without knowledge of the specific manufacturer. The methodology for analyzing the evaluators' preferences and the results are discussed.

The dopaminergic system, and in particular the dopamine D2 receptor, has been profoundly implicated in reward mechanisms in the meso-limbic circuitry of the brain. Dysfunction of the D2 dopamine receptors leads to aberrant substance (alcohol, drug, tobacco and food) seeking behavior. Decades of research indicate that genetics play an important role in vulnerability to severe substance seeking behavior. We propose that variants of the D2 dopamine receptor gene are important common genetic determinants in predicting compulsive disease.

The prevalence of TaqI A alleles of the D2 dopamine receptor (DRD2) gene was examined in two subgroups of medically ill nonalcoholics (more prevalent and less prevalent substance users, MPSU and LPSU, respectively) and in two subgroups of medically ill alcoholics (more severe and less severe alcoholics, MSA and LSA, respectively). The prevalence of the A1 allele in the 80 nonalcoholic and 73 alcoholic patients was 30.0% and 52.1%, respectively (P = 0.009). In the four subgroups of these patients, the prevalence of this allele was: LPSU = 18.2%, MPSU = 34.5%, LSA = 44.4% and MSA = 58.3%. Linear trend analysis showed that as the use of substances and severity of alcoholism increase, so does A1 prevalence (P = 0.001). Specific, subgroup comparisons showed A1 prevalence in MSA to be about 3-fold (P = 0.007) and 1.5-fold (P = 0.04) higher than in LPSU and MPSU subgroups, respectively. Similarly, in a combined analysis of independent studies, A1 prevalence in MSA was higher when compared to LSA (P5 x 10(-3), MPSU (P10(-4) and LPSU (P10(-8) subgroups. There was virtually no difference in the prevalence of the A1 allele between LSA and MPSU subgroups. None of the specific medical or neuropsychiatric complications of alcoholism was associated with the A1 allele. In conclusion, the severity of alcohol dependence in alcoholics and of substance use behaviors in controls are important variables in DRD2 allelic association. The present report and converging lines of evidence suggest that the DRD2 locus could represent a prominent gene risk factor for susceptibility to severe alcoholism. However, other genes and environmental factors, when combined, still play the larger role.

In order to determine whether all the extrinsic salivary glands synthesize transferrin mRNA, the polyadenylated ribonucleic acids [poly(A)+ RNAs] from parotid, submandibular, and sublingual glands, liver, midbrain, testis, spleen, heart, kidney, and the mucosae of oesophagus and stomach from adult male baboons were analysed, using oligo(dT)-cellulose chromatography, agarose gel electrophoresis, followed by transfer of the mRNAs to nitrocellulose filters and identification with transferrin and tubulin cDNA probes. Transferrin and tubulin mRNAs were visualized by autoradiography and analysed by measuring specific activity from beta emitting nuclides following transfer to nitrocellulose filters and hybridizing with [alpha-32P]-labelled human transferrin and tubulin cDNA probes. The results indicate that transferrin mRNA is present in all the extrinsic salivary glands (submandibular, sublingual, parotid) of baboons.

We investigated orofacial manifestations in 42 patients with Melkersson-Rosenthal syndrome who were examined at our institution between 1965 and 1990. Patient histories and histologic and clinical findings were reviewed in detail. These data were compared with the oral findings in 220 cases that were reported in the literature between 1965 and 1990. There were 28 females in our study. The age at onset of signs and symptoms varied widely with a mean of 33.8 years. Most frequent initial signs were labial edema, facial swelling, and Bell's palsy. During the course of the disease, 75% of all patients had labial swelling, 50% had facial edema, and 33% had Bell's palsy. Swelling, erythema, or painful erosions that affected the gingiva, buccal mucosa, palate, or tongue were common intraoral symptoms. A comparison with patients reported in the literature revealed a similar frequency of extraoral symptoms but more prevalent intraoral symptoms in our patients.

The allelic association of the human D2 dopamine receptor gene with the binding characteristics of the D2 dopamine receptor was determined in 66 brains of alcoholic and non-alcoholic subjects. In a blinded experiment, DNA from the cerebral cortex was treated with the restriction endonuclease Taql and probed with a 1.5-kilobase (kb) digest of a clone (lambda hD2G1) of the human D2 dopamine receptor gene. The binding characteristics (Kd [binding affinity] and Bmax [number of binding sites]) of the D2 dopamine receptor were determined in the caudate nuclei of these brains using tritiated spiperone as the ligand. The adjusted Kd was significantly lower in alcoholic than in nonalcoholic subjects. In subjects with the A1 allele, in whom a high association with alcoholism was found, the Bmax was significantly reduced compared with the Bmax of subjects with the A2 allele. Moreover, a progressively reduced Bmax was found in subjects with A2/A2, A1/A2, and A1/A1 alleles, with subjects with A2/A2 having the highest mean values, and subjects with A1/A1, the lowest. The polymorphic pattern of the D2 dopamine receptor gene and its differential expression of receptors suggests the involvement of the dopaminergic system in conferring susceptibility to at least one subtype of severe alcoholism.

If the above two hypotheses are correct, they would require at least one more specific nuclear receptor for T, and at least one membrane receptor to account for the very rapid effects induced by androgens on certain target tissues. If this is the case, clearly a single androgen receptor will not fill the bill.

In a blinded experiment, we report the first allelic association of the dopamine D2 receptor gene in alcoholism. From 70 brain samples of alcoholics and nonalcoholics, DNA was digested with restriction endonucleases and probed with a clone that contained the entire 3' coding exon, the polyadenylation signal, and approximately 16.4 kilobases of noncoding 3' sequence of the human dopamine D2 receptor gene (lambda hD2G1). In the present samples, the presence of A1 allele of the dopamine D2 receptor gene correctly classified 77% of alcoholics, and its absence classified 72% of nonalcoholics. The polymorphic pattern of this receptor gene suggests that a gene that confers susceptibility to at least one form of alcoholism is located on the q22-q23 region of chromosome 11.

The nuclear uptake and retention of 3H-dihydrotestosterone (3H-DHT) were studied in the reproductive organs of the male hamster by autoradiography. Castrated adult male hamsters were infected with 0.2/μg of 3H-DHT (107 Cl/mmole/100 g body weight) and sacrificed 1 1/2 hours later. The epididymides, prostate glands, and seminal vesicles were removed and processed for autoradiography. Localization of the androgen was observed in the nuclei of the secretory cells of all three organs. The nuclei of the smooth muscle cells of the muscularis and the connective tissue cells of these organs also demonstrated varying degrees of nuclear labeling. In addition, nuclear uptake was observed in the smooth muscle of the tunica media of the blood vessels of all three organs. In comparison to other studies, the results demonstrate species variation in the uptake of androgens in the accessory reproductive organs and support recent data that suggest that the cardiovascular system is a target organ for androgens.

Autoradiographs of tissue slices from livers perfused with 1 x 10(-9) M-1-O-[3H]octadecyl-2-acetyl-sn-glycero-3-phosphocholine ([3H]18:0-sn-3-AGEPC) indicate that binding of this agonist is localized in the portal venules in anterograde perfused livers, and in the central venules in retrograde perfused livers. The pattern of silver grains in anterograde perfused liver was not affected significantly by prior exposure to 100-fold excesses of unlabelled 16:0- or 18:0-sn-3-AGEPC, 16:0-sn-1-AGEPC, or a 1000-fold excess of U.66985. [3H]18:0-sn-3-lyso-GEPC produced the same pattern of binding as the acetylated analogue. Measurement of glucose release stimulated by 16:0-sn-3-AGEPC demonstrated that the retrograde perfused liver was nearly 1000-fold less sensitive to this compound than the anterograde perfused liver. Exposure of the livers to bovine serum albumin prior to 5 x 10(-11) M-[3H]18:0-sn-3-AGEPC resulted in inhibition of stimulated glucose release, and decreased both the amount of label retained in the livers and the amount of silver grains over the portal sinusoidal cells without affecting the amount of grains seen over all other regions of the liver. Glucose release from primary monolayer cultures of hepatocytes or suspensions of liver slices was not stimulated by 16:0-sn-3-AGEPC. The results suggest that specific binding of [3H]18:0-sn-3-AGEPC is restricted to the portal side of the liver microvasculature, the majority of binding is nonspecific, and the biological response to AGEPC requires an intact and perfused vasculature.

Women have a greater incidence of autoimmune thyroiditis, thyroid cancer and radiation-induced carcinogenesis than men. Over the past several years we have examined for the presence of steroid receptors in both humans and non-human primates. In this study we examined the nuclear uptake and retention of 3H-testosterone, the main circulating androgen in mammals, in different cells of the thyroid gland of baboons, our non-human primate model. Castrated-adrenalectomized male baboons were injected with 3H-testosterone (1 microgram/kg bw) and killed 1 1/2 h later. The thyroid glands and other tissues were removed and processed for autoradiography. Nuclear localization of 3H-testosterone or one of its metabolites was found in a small fraction of the follicular cells (approximately 10-20%). The discrepancy between these findings and those previously obtained with 3H-dihydrotestosterone (virtually 100% of the follicular cells concentrated the 3H-steroid) are discussed. The results from this study and those of the past strongly support a direct action of androgen on the thyroid. Whether a direct action of androgen on the thyroid is related to smaller incidence in autoimmune thyroiditis, thyroid cancer and radiation-induced carcinogenesis in men than women remains an unanswered question at the present time.

SUMMARY The administration of a high dose of androgen on a single day to a neonatal female rat has been shown repeatedly to induce persistent vaginal cornification (PVC). However, this type of treatment does not parallel the continuous androgen secretion present in the male, and the high doses that have been used could represent a pharmacological and not a physiological effect. Experiments were carried out to determine the minimal effective dose of testosterone propionate (TP) needed to cause PVC when the androgen is administered to the neonatal rat for the first 10 days of life or as a long-acting ester. Injection of 1, 3 or 9 μg TP on days 1–10 of life in female rats induced PVC in adulthood. All three doses were found to be more effective than a testicular transplant on day 1. In female rats injected with low doses of TP twice daily for the first 10 days of life, PVC was shown between 90 and 100 days of life in 21 out of 22 animals given 0·5 μg TP/injection, and in eight out of 22 animals given 0·05 μg TP/injection. In an experiment where female rats were given a single injection of 0·1, 1·0 or 10·0 μg TP, or 0·1 or 1·0 μg testosterone cyclopentylpropionate (TC, a long-acting androgen) on the first day after birth, PVC occurred at 90–100 days of age in 15 of the 18 animals which were injected with 10 μg TP, in none of the 17 animals which were injected with 1 μg TP, and in 10 of 11 animals which were injected with 1 μg TC. The effects of all treatments on vaginal opening, first oestrus, ovarian weight, body weight and sexual behaviour are reported. The use and implications of low dose regimens are discussed in relation to the construction of an experimental model for the study of sexual differentiation.

Two experiments were carried out to determine whether the serum gonadotropin levels found in the neonatal female rat play a role in the sexual differentiation of the neuroendocrine axis. Female rats were injected either with 100 μg of testosterone propionate (TP) on day 2 or day 3, or with the combination of TP and gonadotropins (5O μg of FSH and 5O μg of LH/day for 3 days). When animals receiving both gonadotropins and TP were compared with those receiving TP alone, it was observed that gonadotropins significantly delayed or prevented the onset of persistent vaginal estrus (p < 0.01) and significantly ameliorated both the decrease in ovarian weight (p < 0.05) and the loss of female sexual behavior (p < 0.05) due to the injection of testosterone propionate. The possible sites of action for the gonadotropins and a hypothesis for the mechanism of action are discussed. (Endocrinology 92: 500, 1973)

The intracellular distribution of unbound estrogen receptor was estimated using nonaqueous and aqueous isolation of nuclei and autoradiography. The estimated amount of nuclear receptor varied greatly with the procedure used and thus caution is urged in approximating the in vivo intracellular distribution of receptors.

The classical model for the mechanism of action of steroids holds that unbound receptors for steroids reside exclusively in the cytoplasmic compartment and that they undergo translocation to the nucleus when bound to steroids in a process which is temperature sensitive. In the present study we looked at the localization of the estradiol receptor using autoradiography and biochemical procedure. Uteri from ovariectomized and/or ovariectomized-adrenalectomized rats, as well as several cell lines (with estrogen receptor (ER+) were incubated with [3H]-estradiol or [3H]-R2858 (methoxy-17-ethinylestradiol) for 5 min to 2 h at different concentrations of ligands (0.1-10 nM) at 4 degrees C. When the tissue or cells were processed for autoradiography the localization of steroid was nuclear and cytoplasmic. In contrast when the tissue or cells were processed using the usual biochemical procedures, all binding activity appeared in the cytosolic fraction. In addition, when concentrated preparations of homogenized uteri as well as several nuclear preparations from cell lines were made, free receptor could be demonstrated in the crude nuclear preparations. In the present study, data are presented which suggest that there are unbound receptors for estrogen in nuclei of the smooth muscle cells of myometrium as well as in nuclei of the several cell lines (ER+). We propose a new model for the distribution of estrogen receptors in which unbound receptors are in equilibrium, partitioned between nucleus and cytoplasm according to the free water content of these intracellular compartments.

We evaluated the serological reactivity of a protease-resistant antigen designated 4D which was encoded by Treponema pallidum DNA and was expressed in Escherichia coli from recombinant plasmid pAW329. This 19,000-molecular-weight antigen was purified in its native, non-protease-treated form from E. coli sonic extracts by molecular sieving and ion-exchange chromatography. Antibody binding to antigen 4D was detected by a radioimmunoassay. Antigen 4D-specific antibody was detected in 95% of the sera in a Centers for Disease Control syphilis serum panel. It was also detected in 55% of 121 primary syphilis patients, whereas syphilis antibody was detected in 83% of the sera by a fluorescent treponemal antibody absorption test and in 88% of the sera by a T. pallidum microhemagglutination test. In tests of 118 normal sera, less than 3% demonstrated antibody to antigen 4D; these results are similar to microhemagglutination and fluorescent treponemal antibody absorption test results. Rabbit antisera against Treponema phagedenis, Treponema refringens, Treponema denticola, and Treponema vincentii did not react with antigen 4D.

Autoradiography has been used in the past to locate presumptive receptor systems for a number of steroids. It has provided information in rather complex tissues that could not have been obtained by biochemical procedures. In these studies we made use of autoradiography to redirect our biochemical efforts to study androgen receptors in the primate heart. Castrated-adrenalectomized female rhesus monkeys and baboons were injected with 1 microgram and 5 alpha-dihydro-[1,2,4,5,6,7-3H]-testosterone per kilogram of body weight. The animals were killed 1 hour later and the hearts were removed and processed for autoradiography. A nuclear localization of androgen was found in most of the myocardial cells, but in few if any of the interstitial cells. After reviewing the autoradiographic data, we began a new series of biochemical studies using a new buffer system and unlabeled androgen to stabilize the receptor. This in combination with postlabeled gradients allowed us to demonstrate for the first time 8S binding on sucrose density gradients. We feel that autoradiography can be a useful adjunct to biochemical studies even in "less complex" tissue such as the cardiac muscle.

Modulation of the uptake and retention of estradiol-17beta in the ovine corpus luteum by luteinizing hormone (LH) is described. The uptake and retention of tritiated estradiol by the corpus luteum (induced by superovulation) was maximal through Cycle Days 8-12 with little or no up take and retention during luteinization or regression. Uptake and retention were significantly reduced (p less than .05) on Days 13-14 then increased on Day 15. LH inhibited the uptake of estradiol on Days 9-12 but had no effect during Days 2-5 nor at the end of the cycle (Day 15). Neither follicle stimulating hormone nor prolactin inhibited the uptake and retention of estradiol via stimulation of progesterone synthesis. These results demonstrate a specific uptake and retention of tritiated estradiol by isolated luteal cells from ewes which varies as a function of the stage of the estrous cycle.

An improved procedure for producing high quality autoradiograms has been developed. This procedure decreases the time involved in processing the tissue. Improvements in darkroom conditions, sectioning techniques, and staining procedures enable the technician to process a large volume of slides in the shortest time possible. The improved quality of the finished product makes interpretation of the results much easier. This procedure could be incorporated by any laboratory which finds autoradiography necessary to its work.

Aqueous zinc acetate injected ip prevented tumor growth in 50-70% of BDF male mice previously inoculated ip with L1210 leukemia cells. However, aqueous zinc acetate injected sc did not prevent tumor growth in AKR/J mice inoculated im with BW5147 lymphatic leukemia cells. In the latter mice, only a small but statistically significant increase in mean survival was noted.

Many heroin addicts and addicts on methadone treatment exhibit sexual dysfunction. It is believed that the primary site of action of the opiates is the hypothalamic-hypophyseal system. Although it is not known how the opiates might alter the hypothalamic-hypophyseal system, it has recently been suggested that the opiates might mimic the steroids by binding to steroid hormone receptors. To test this hypothesis, in vivo autoradiographic studies and in vitro biochemical studies were conducted to see if the binding of androgen to receptors in the central nervous system would be affected by the opiates. In the autoradiographic studies, animals were treated for 10 days with saline, morphine sulfate (50 mg/kg), or methadone hydrochloride (10 mg/kg) and then injected with 3H-dihydrotestosterone (DHT-0.5 microgram/100 grams body weight). The animals were killed 1 hour later and their brains were removed and processed for autoradiography. No significant effects of opiates on nuclear uptake and retention of androgen by the limbic system were found. In the in vitro binding studies, 3H-DHT (5 X 10(9) M) and 3H-estradiol (5 X 10(-9) M) were incubated with cytosol prepared from brain in the presence of varying concentrations of morphine sulfate (10(-3) - 10(-9) M) and methadone hydrochloride (10(-3) - 10(-9) M). Using three different assay systems (LH-20, hydroxylapatite, and sucrose density gradient centrifugation), no consistent effects of opiates on steroid binding to its receptor could be demonstrated. These data along with previously reported data suggest that the opiates do not induce sexual dysfunction by interacting with steroid receptors.

Female rats were injected with3H-diethylstilbestrol. The pituitaries, oviducts, and uteri were removed and processed for autoradiography. The nuclear uptake and retention in these tissues appeared similar to that seen after the injection of3H-estradiol except in the pars nervosa of the pituitary gland.

The uptake and retention of radiolabelled dihydrotestosterone or one of its metabolites by both the male and female reproductive organs were examined in the baboon 2 male and 2 female baboons were injected intravenously with 1 micrograms/kg body weight of 3H-dihydrotestosterone and 2 animals, 1 male and 1 female, were injected with both labelled and 100 micrograms/kg body weight of radio-inert dihydrotestosterone. 1.5 h the injections, the animals were sacrificed and the uterus, cervix, vagina, uterine tube, labia minora, seminal vesicles, prostate, ductus deferens, and prepuce were removed and treated for autoradiography. The stratified squamous epithelia of the cervix, vagina, labia minora and prepuce demonstrated uptake of label in the germinative, but not in the superficial, cell layers. The columnar cells lining the uterine tube and cervical glands, but not the uterine glands, were labelled. In addition, the nuclei of the cells in the luminal epithelium of the prostate and seminal vesicles contained silver grains. The interstitial cells of the seminal vesicles, prostate and ductus deferens, and the smooth muscle of the prostate and ductus deferens, but not the seminal vesicles, demonstrated an uptake of radioactivity.