Prostatic aspiration biopsy: an assessment of accuracy based on long-term observations

We present the results of transrectal thin needle aspiration biopsy of the prostate in 133 patients. Test specificity was 94 per cent and sensitivity also appeared to be high initially. However, with repeated rectal examinations and biopsies during an 11-year period a number of additional false negatives became apparent, which resulted in an apparent test sensitivity of 82 per cent, lower than most previously published reports. Our data suggest that aspiration biopsy has specificity and sensitivity similar to core biopsy, it is important to re-test patients who have a palpable abnormality and an initially benign biopsy, and aspiration biopsy simplicity allows for a low threshold of suspicion of subtle abnormalities and for repeating biopsies after negative findings.

Accidental and homicidal death in a psychiatric emergency room population

To identify potentially preventable mortality other than suicide among psychiatric emergency room patients, the authors compared the rates of accidental and homicidal death among 5,284 consecutive psychiatric emergency room patients with those expected for an age-, sex-, and race-matched sample of the general population. The rate of accidental death was two and one-half times and the rate of homicidal death nearly twice the expected rate for the matched general population. Diagnostic and demographic analyses indicated that increased risk of death from either cause was highest among alcoholics, schizophrenic patients, and males. The implications of the findings for clinical care are discussed.

Epidural hematoma as a cause of postpneumonectomy paraplegia

Postpneumonectomy paraplegia developed in a woman admitted for resection of bronchogenic carcinoma. Postpneumonectomy paraplegia is an uncommon, but catastrophic, event that is thought to be caused primarily by ischemia to the spinal cord; in this instance an epidural hematoma was the cause. Recommendations for prevention are presented.

Prescribing practices among nurse practitioners in adult and family health

Data derived through log recordings of 89 nurse practitioners (NPs) in adult/family practice on 7,086 prescriptions issued during 890 clinical days were analyzed to describe prescribing practices of NPs who held prescriptive authority from the licensing regulatory boards of five western states. Results showed drug utilization to be similar to physician prescribing data, and intensity of prescribing to be less than that of physicians. The distributions of prescriptions by drug category and in relation to health problems underlying prescriptions are reported. Confidence with prescribing by type of drugs was parallel to incidence of prescriptions within drug category. Physician consultation prior to prescribing occurred with highest incidence for health problems treated with least frequently prescribed drugs. Physician consultation or referral was reported for 14.3 per cent of prescriptions.

Reduction in prostatic concentration of endogenous dihydrotestosterone in rats by hyperprolactinemia

Persistently high levels of circulating prolactin can be achieved in male rats when pituitaries from female donors are grafted under the renal capsule. Enhanced growth of the lateral prostate can be accomplished by an apparent synergistic effect of excess prolactin with subphysiologic doses of testosterone. To define this effect we measured the endogenous dihydrotestosterone (DHT) concentrations in rat prostate lobes. Twenty Sprague-Dawley male rats (250 g) were castrated and given subcutaneous implants of silastic tubing filled with 1 cm of crystalline testosterone. Ten of these rats simultaneously received two pituitary grafts under the renal capsule. The remaining ten rats received intrarenal skeletal muscle grafts as controls. Four weeks later, the weight (mg +/- SE) of the ventral and dorsal lobes were not significantly different between the two groups, while the lateral lobe was significantly (P less than 0.01) heavier in rats with pituitary grafts (121.4 +/- 7.5) than in controls (81.7 +/- 10.4). Endogenous DHT in the tissue extracts was determined by radioimmunoassay following KMnO4 treatment to eliminate testosterone. The concentration of DHT (ng/g tissue +/- SE) was significantly (P less than 0.01) lower in the lateral prostate of graft-bearing animals (4.40 +/- 0.29) than in the controls (5.98 +/- 0.34). These results indicate that, in the rat, hyperprolactinemia induced by pituitary grafts is associated with a heavier lateral prostate and a lower concentration of endogenous DHT in that tissue. These results also suggest that the action of prolactin in the rat prostate is not mediated through the action of androgen.

An in vitro approach to studying cutaneous metabolism and disposition of topically applied xenobiotics

The extent to which cutaneous metabolism may be involved in the penetration and fate of topically applied xenobiotics was examined by metabolically viable and structurally intact mouse skin in organ culture. Evidence that skin penetration of certain chemicals is coupled to cutaneous metabolism was based upon observations utilizing [14C]benzo[a]pyrene (BP). As judged by the recovery of radioactivity in the culture medium 24 hr after in vitro topical application of [14C]BP to the skin from both control and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced C3H mice, skin penetration of BP was higher in the induced tissue. All classes of metabolites of BP were found in the culture medium; water-soluble metabolites predominated and negligible amounts of unmetabolized BP were found. As shown by enzymatic hydrolysis of the medium, TCDD induction resulted in shifting the cutaneous metabolism of BP toward the synthesis of more water-soluble conjugates. Differences in the degree of covalent binding of BP, via diol epoxide intermediates to epidermal DNA, from control and induced tissues were observed. These differences may reflect a change in the pathways of metabolism as a consequence of TCDD induction. These results indicated that topically applied BP is metabolized by the skin during its passage through the skin; and the degree of percutaneous penetration and disposition of BP was dependent upon the metabolic status of the tissue. This suggests that cutaneous metabolism may play an important role in the translocation and subsequent physiological disposition of topically applied BP.

The distribution of dermal tumorigens in coal liquids: relationship of tumorigenicity and microbial mutagenicity

Polycyclic aromatic hydrocarbons and/or their pyrolle derivatives were found to be the primary contributors to the skin tumorigenicity of the neutral fractions of two coal oils. Mutagenicity of the neutral fraction in Salmonella test strains was found to be due primarily to polycyclic aromatics containing polar substituents. Thus, the chemical classes responsible for skin tumorigenicity differ from those responsible for mutagenicity.

A multisample apparatus for kinetic evaluation of skin penetration in vitro: the influence of viability and metabolic status of the skin

An apparatus is described for convenient in vitro quantitation of the rate, extent, and character of living skin penetration by chemicals. Evidence that viability markedly affects epidermal penetration was based upon observations utilizing benzo(a)pyrene. This compound displayed saturation kinetics in the extent of penetration, marked elevation in the rate, and extent of penetration following induction of epidermal mixed function oxidase and negligible penetration of skin previously frozen. These data are interpreted to indicate that for certain compounds, such as benzo(a)pyrene where cutaneous metabolism is expected, meaningful in vitro measures of skin penetration should take into consideration the biochemical viability and metabolic status of the tissue.

Use of laser-excited fluorescence to measure mixed-function oxidase activity

The microsomal mixed-function oxidase (MFO) system is involved in the metabolism of various chemical compounds. Polycyclic aromatic hydrocarbons are metabolized by the cytochrome P-448 enzyme system, which contains MFOs. Induction of this MFO activity may be useful as an indicator of the toxicity of the inducer material. We have successfully used a portable centrifugal analyzer equipped with an argonion laser light source to quantify cytochrome P-448 activity induced in mouse-liver microsomes by exposing the animal's skin to different doses of liquids derived from a coal-liquefaction process. The MFO activity was determined kinetically by measuring the rate at which the highly fluorescent compound, resorufin, produced by the oxidation of 7-ethoxyresorufin substrate, was formed. The 514.5-nm laser excitation beam was directed with a fiber-optic bundle from the laser to the cuvets of a specially designed rotor; emitted fluorescence was monitored at 90 degrees to the incident beam through a 560-nm cut-on secondary filter. Use of the laser excitation source allowed very low MFO activities to be measured: picomole quantities of resorufin could be determined. We anticipate that the increased sensitivity of the method described here will allow MFO activities to be determined in body fluids and skin.

Use of laser-excited fluorescence to measure mixed-function oxidase activity

The microsomal mixed-function oxidase (MFO) system is involved in the metabolism of various chemical compounds. Polycyclic aromatic hydrocarbons are metabolized by the cytochrome P-448 enzyme system, which contains MFOs. Induction of this MFO activity may be useful as an indicator of the toxicity of the inducer material. We have successfully used a portable centrifugal analyzer equipped with an argonion laser light source to quantify cytochrome P-448 activity induced in mouse-liver microsomes by exposing the animal's skin to different doses of liquids derived from a coal-liquefaction process. The MFO activity was determined kinetically by measuring the rate at which the highly fluorescent compound, resorufin, produced by the oxidation of 7-ethoxyresorufin substrate, was formed. The 514.5-nm laser excitation beam was directed with a fiber-optic bundle from the laser to the cuvets of a specially designed rotor; emitted fluorescence was monitored at 90 degrees to the incident beam through a 560-nm cut-on secondary filter. Use of the laser excitation source allowed very low MFO activities to be measured: picomole quantities of resorufin could be determined. We anticipate that the increased sensitivity of the method described here will allow MFO activities to be determined in body fluids and skin.

Suicide in a psychiatric emergency room population

Twenty-two suicides were identified in a series of 5,284 psychiatric emergency room patients, yielding a suicide rate of 111.1 per 100,000 "patient-years at risk"--more than seven times the age- and sex-adjusted rate for the general population. Subpopulations at high risk were white people, men, depressed and schizophrenic patients, substance abusers, and patients with multiple emergency room visits. No patients had killed themselves immediately after an emergency room visit, but several had killed themselves without following through on a referral from the emergency room to another facility for treatment. The authors discuss the implications of these findings for emergency room practice and for further research.

Quantitation of cutaneous toxicity: an in vitro approach using skin organ culture

A short-term (48 hr) organ culture system for maintaining metabolically viable and structurally intact mouse skin has been developed. With the culture system, the responses of skin to in vitro physical and chemical insults were assessed by histologic examination and selected biochemical measurements in an attempt to establish a quantitative basis for the evaluation of cutaneous toxicity in vitro. In studies with mouse skin in organ culture following either freeze-thaw treatment (physical insult) or a single in vitro topical application of tributyltin chloride (10 to 1000 nmole/cm2), deleterious morphologic changes were observed. The degree of cellular injury was reflected by inhibition of in vitro incorporation of [3H]thymidine and [14C]leucine into epidermal DNA and protein, respectively; there also was leakage of intracellular enzymes into the culture medium in a dose and time related manner. These biochemical parameters are sensitive indicators of cellular injury; as such they may offer a simple, sensitive, and quantitative measure for assessing cutaneous toxicity of chemicals in vitro.

Dosimetry of PAH skin carcinogenesis: covalent binding of benzo[a]pyrene to mouse epidermal DNA

Benzo[a]pyrene (BaP) is metabolized to the chemically reactive anti and syn isomers of the 7,8-diol-9,10-epoxides of BaP (BPDE) which bind covalently to DNA to form DNA/BPDE complexes. Tetrols liberated from the DNA/BPDE complex by acid hydrolysis are easily quantified by h.p.l.c. using fluorescence detection. This approach allows femtomole amounts of BPDE associated with the DNA isolated from a single mouse to be detected using conventional instrumentation. The usefulness of this technique to estimate the interaction of BaP with DNA of mouse skin, both in the intact animal and in organ culture, was investigated. With mouse skin in organ culture it could be demonstrated that: (i) upon a single topical application of 5 micrograms of BaP, binding to DNA occurred via BPDE at a linear rate for up to 65 h, (ii) the amount of binding was dose dependent at concentrations of BaP less than 10 micrograms.

Immunoselection of tumor cell variants by mice suppressed with ultraviolet radiation

It has previously been shown that mice exposed to ultraviolet radiation (UV) fail to reject highly immunogenic UV-induced tumors, which are regularly rejected by normal mice. The present study shows, however, that this immunosuppresion is incomplete, as UV-treated mice can still mount certain tumor-specific immune responses and reject smaller inocula of tumor cells that regularly grow progressively in athymic nude mice. Furthermore, all tumor cell lines that were reisolated from the tumor mass resulting from one tumor passage through UV-treated recipients heritably lost a tumor-specific determinant present on the parental tumor cells used for transplantation, and a large percentage of these reisolated variant tumors had changed to progressively growing tumors, in that they were no longer rejected by normal mice. In contrast, none of the tumors reisolated from passage through athymic nude mice or anti-idiotypically suppressed mice showed this change in antigenicity and progressive growth behavior. Thus, it appears that the phenotypic change in tumors reisolated from UV-treated mice was caused by immunoselection, and that the tumor-specific immunity in these mice apparently restrained the outgrowth of the parental tumor cells despite the partial immunosuppression. Because of the regularity at which tumor variants arose in the UV-treated mice after tumor transplantation, it appears that the partial immunosuppression caused by UV-treatment may have favored the outgrowth of antigenic variants from the parental tumor cell population, possibly by allowing more time for the generation of tumor variants. A similar immunoselection process might be part of tumor progression during tumor development and preferentially occur in cancer-bearing individuals showing concomitant tumor immunity.

Mechanisms of syngeneic tumor rejection. Susceptibility of host-selected progressor variants to various immunological effector cells

The ultraviolet radiation-induced fibrosarcoma 1591 generally is rejected by normal syngeneic mice and only rarely exhibits progressive growth. We isolated five of these rare progressor tumors from normal animals to determine the selective pressures that had been exerted upon the parental tumor by normal immunocompetent hosts. We found that the variant tumor cell lines could neither induce nor be killed by tumor-specific lymphocytes, suggesting that selection had been exerted against tumor cells expressing the tumor-specific antigen. In contrast, no selection against natural killer cell activity or against nonspecific T cell-mediated immunity seems to have occurred because progressor tumor cells were highly sensitive to these types of effector cells and in fact induced these effector cells more effectively than did the parental tumor. Nude mice were found to be as capable as normal mice in generating natural killer activity in response to a challenge with progressor tumor cells, but they were unable to mount a nonspecific T lymphocyte response. This may account for the fact that the progressor tumors grew at a significantly faster rate in nude animals than in normal mice. Thus, our study shows that in this tumor system nonspecific T cell-mediated immunity may play a role in retarding tumor growth, but the absolute resistance of normal animals to progressive tumor growth critically depends upon the presence of T cell-mediated tumor-specific immunity. Furthermore, neither NK cells nor nonspecific cytotoxic T lymphocytes appear to play a role in immunoselection against this tumor in normal immunocompetent hosts.

An anatomic and histologic study of the rat prostate

Various morphologic features of the rat prostate complex were characterized by anatomic dissection and by light microscope histology. The prostate complex is viewed as a whole and it is related to the individual portions of the male reproductive system. The three lobes of the prostate are designated as ventral, lateral, and dorsal according to their relation to the urethra. These lobes are connected to the urethra by fascia and a series of ducts. Relations of the prostate to the seminal vesicles, coagulating glands, vas deferens and ampullary glands, urinary bladder, and ureters are described. Vascular supply is also reviewed. While the acinar pattern of each prostatic lobe is unique, the dorsal and lateral lobes more closely resemble each other than the ventral lobes.

Poly (ADP-ribosylation) in N, N-diethylnitrosamine-treated mice

1. Liver nuclei isolated from male mice treated with the carcinogen N, N-diethylnitrosamine were examined for the homopolymer poly(adenosine diphosphate ribose) and for the activity of the conjugate polymerase. 2. At all levels of the carcinogen tested, a concomitant increase in both poly(adenosine diphosphate ribose) content and activity of the enzyme were found. 3. Both responses were transitory and dose dependent.

Performance of brain-damaged and non-brain-damaged institutionalized children on the Minnesota Percepto-Diagnostic Test

Examined the performance of 64 children on the Minnesota Percepto-Diagnostic test (MPD) who were diagnosed as either Brain-Damaged (BD) or emotionally impaired Non-Brain-Damaged (NBD). There were 31 children in the NBD group and 33 in the BD group. The MPD T-score and Actuarial Table significantly differentiated between the two groups. Seventy-four percent of the combined BD-NBD groups were identified correctly. Additional discriminant analysis on this sample yielded combined BD-NBD groups classification rates that ranged from 77% with the MPD variables Separation of Circle-Diamond (SPCD), Distortion of Circle-Diamond (DCD) and Distortion of Dots (DD) to 83% with the WISC-R three IQ scores plus the MPD T-score, SPCD and DD. The MPD T-score and Actuarial Table (MPD Two-Step Diagnosis) appeared to generalize to other populations more readily than discriminant analysis formulae, which tend to be sensitive to the samples from which they are derived.

Christmas and psychopathology. Data from a psychiatric emergency room population

It is widely believed among psychiatrists and laymen alike that Christmas and other holidays are associated with an increased incidence of psychopathology. Statistical studies, however, consistently have been shown the Christmas season to be associated with a low incidence of suicide and psychiatric hospitalization. The present study examines the number and type of visits to a 24-hour psychiatric emergency service over a seven-year period. There is a decrease in the number of visits during the days and weeks before Christmas and an increase of roughly the same magnitude afterward. The effect is more prominent for women and older persons but does not seem to differentially affect persons of different racial, marital, or diagnostic status.

Induction of O-deethylase activity as an index to exposure to coal-derived products and trace environmental pollutants

The metabolism of the synthetic substrate 7-ethoxyresorufin is a selective measure of the activity of cytochrome P-448 monooxygenase, the subset of cytochrome P-450-mediated enzymes preferentially induced by polycyclic aromatic hydrocarbons and related compounds. 7-Ethoxycoumarin metabolism, on the other hand, reflects total (nonselective) cytochrome P-450 monooxygenase activity. Either substrate yields a single, highly fluorescent product, amenable to direct, sensitive assay with the portable centrifugal analyzer. We used three assays with liver microsomes from C57/BL6 mice for the short-term bioassay of the dose-dependent effects of exposure to selected environmental toxins, including petroleums, polychlorinated biphenyls, and their oxidative degradation products.