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In this analytical study, aspects of the design of 41 epidemiologic studies pertaining to the relationship between parental/household smoking and the prevalence of respiratory symp toms and certain illnesses in preschool children (0-5 years old) were examined using a sys tematic protocol developed previously for a similar analysis of epidemiologic studies in school-age or older children. Wide variability was observed from study to study in the consid eration of 21 predetermined potential confounding variables. While the socioeconomic status (SES), family health history, subject's personal health history, family size, age and gender were considered in 50% or more of the studies, indoor pollution (other than gas stove usage), day care use, animal exposures, stress, dampness/cold, season, occupational exposures, nutri tional status of the subject, and maternal smoking during pregnancy were considered infre quently (in < 25% of the studies) or not at all. A wide variation was also observed from study to study in the array of confounders considered. When evaluated on the basis of number of confounders considered per study, only 3 of the 41 papers considered 10 or more of the 21 predetermined variables. The clinical endpoints, usually obtained from parental question naire responses, were validated by medical records or physician examination in only slightly more than 50% (21/41) of the relevant epidemiologic studies. Twelve of the 21 predeter mined confounders were analyzed in detail. There was wide variation in and a lack of stan dardization of the criteria used as indices of SES, family and personal health history, and age. There was also marked variation among the studies in methods used, if any, to adjust for confounding variables. Several of the confounding variables that we looked at appeared to be consistently associated with increased risk of respiratory illness in preschool children, includ ing family and personal health history, young age, male gender, day care use and season. On the other hand, no consistent association was observed for SES, artificial feeding, gas fuel use and indoor pollution, while equivocal or uncertain data in this regard were obtained for dampness/cold and heating/air-conditioning. While no consistent interactions between var ious confounders were observed, the relationship between parental/household smoking and respiratory illness in preschool children appeared to vary inversely related to age. Before epidemiologic associations between parental smoking and respiratory health in preschool children can be concluded to reflect any effects of ETS on the respiratory system of these children, it will be necessary to more thoroughly and more consistently consider the role of a number of potential confounding variables, both individually and in combination. It will also be necessary, before reaching such conclusions, to control and/or adjust for these factors where appropriate, as well as to more consistently validate parental questionnaire-based clin ical endpoints.

The issue of environmental tobacco smoke (ETS) exposure of children and respiratory health effects remains a matter of considerable controversy. We undertook to conduct a comprehensive and updated critical review and objec tive analysis of the epidemiological literature relevant to possible associations between ETS exposure and respiratory health of children. There appears to be a consistent association between parental (primarily maternal) smoking and respiratory symptoms and certain diseases in preschool children (44 reports). On the other hand, there is no consistent association between parental smok ing and (1) respiratory symptoms or disease (46 reports); (2) middle ear dis ease (17 reports), (3) pulmonary function (38 reports), or (4) lung growth and development (5 reports) in school-age or older children. Possible explanations for these data and the age-related differences noted include (1) an ETS effect, with age-dependent variations in susceptibility and/or exposure to ETS; (2) pregnancy and/or lactational effects of maternal active smoking; (3) inac curacies related to unvalidated clinical data and smoking status misclassifica tion, and (4) variable treatment of socioeconomic status-related and other confounding factors. The available data relative to these issues is inconclusive, and which of these explanations pertain remains to be determined by further research.

This case illustrates a comprehensive approach to assessing causality in a woman with apparent cognitive dysfunction, as measured by neuropsychological testing, and a 10-year history of occupational exposure to ethylene oxide. The analysis included a multidisciplinary examination of the patient, which took place several years after the termination of her exposure. In addition, all of the patient's prior medical and psychiatric records were reviewed, as were the records of her employer to ascertain her exposure history. Our evaluation revealed a pattern of neuropsychological findings not consistent with nervous system damage secondary to an organic effect of ethylene oxide. A more likely causal hypothesis is adopted the patient's apparent cognitive dysfunction had a psychiatric etiology. This case also illustrates the potential impact of a patient's involvement in legal proceedings related to claims of neurocognitive dysfunction.

Studies were undertaken to identify intracellular mediators of prolactin inhibition of glucocorticoid-induced apoptosis in Nb2 lymphoma cells. A short-term assay was implemented that quantitates fragmented DNA released from the genome by reaction with diphenylamine. Induction and inhibition of internucleosomal DNA cleavage (indicative of apoptosis) was verified by agarose gel electrophoresis of extracted cellular DNA. Synchronized Nb2 cells (G0/G1) exhibited increased DNA fragmentation after 4-hr incubation with dexamethasone (DEX) (25–100 nM) which was inhibited by ovine prolactin (oPRL) (0.1-1 ng/ml), the glucocorticoid receptor antagonist, RU486 (500 nM), and the nuclease inhibitor, aurintricarboxylic acid (100 nM). Signals previously implicated in prolactin induction of mitogenesis in Nb2 cells were investigated for their role in prolactin inhibition of apoptosis including: protein kinase C activation, arachidonic acid metabolism, polyamine production, tyrosine phosphorylation, and extracellular calcium. Protein kinase C agonists, phorbol-12-myristate-13-acetate, and 1,2-dioctanoyl-sn-glycerol, ± the calcium lonophore, A23187 (200 nM), did not mimic oPRL inhibition of DEX-induced DNA fragmentation. Protein kinase C inhibitors, gossypol and quercetin, did not block prolactin action. Arachidonic acid did not mimic prolactin protection against DEX-induced DNA fragmentation. Inhibitors of arachidonlc acid metabolism, 5, 8, 11, 14-eicosatetraynoic acid, nordlhydrogualaretic acid, and indomethacin did not block prolactin action. The polyamine, spermine, inhibited DEX-induced DNA fragmentation at 1.5 to 2.5 mM. However, inhibition of polyamine synthesis with α-difluoromethyl ornithine or methylglyoxal bis(guanylhydrazone) did not inhibit prolactin action. Prolactin action was not blocked by Inhibitors of tyrosine kinase activation, genistein and tyrphostin-47. On the other hand, pervanadate, a potent tyrosine phosphatase inhibitor, consistently inhibited DEX-induced DNA fragmentation. Prolactin action and DEX-induced apoptosis both occurred in calcium-free PBS. In summary, protein kinase C activation and eicosanoid production do not appear to mediate this prolactin action. Although spermine could block DNA fragmentation, blockade of the polyamine cascade did not inhibit prolactin action, suggesting that polyamines do not mediate this prolactin effect. While inhibitors of tyrosine kinase activation did not block prolactin action, tyrosine phosphatase inhibition in the presence of basal tyrosine kinase activity mimicked prolactin action, suggesting tyrosine phosphorylation participation in the anti-apoptotic effect. Extracellular calcium was not required for prolactin or DEX action.

The interaction between the immunosuppressive effects of glucocorticoids and the mitogenic effects of prolactin (PRL) were examined in Nb2 lymphoma cells, a pre-T cell line. The synthetic glucocorticoid, dexamethasone (Dex), caused a concentration-dependent (6.25–200 nM) inhibition of basal and ovine PRL (oPRL)-stimulated Nb2 cell proliferation. Although Dex was antiproliferative, the steroid had no effect on cell viability in the presence of PRL. However, when PRL was omitted from the medium, Dex increased the proportion of dead Nb2 cells by 24 hr in a concentration (25-200 nM)-dependent fashion without affecting total cell number. The antiproliferative and cytolytic effects of Dex were mimicked by other corticosteroids (cortisol, corticosterone, aldosterone, and deoxycorticosterone) in the expected order of glucocorticoid potency, but not by other steroids (17-β-estradiol, progesterone, testosterone, 5-α-dihydrotestosterone, and dehyhroepiandrosterone) or triiodothyronine. In addition, the antiproliferative and cytolytic effects of glucocorticoids were antagonized by the glucocorticoid receptor antagonist RU 486.Since corticosteroid-induced cytolysis was apparent only in the absence of mitogen, the anticytolytic effects of oPRL were tested. In the presence of Dex (100 nM), oPRL (25–1600 pg/ml) caused a concentration-dependent inhibition of cytolysis without changing cell number. Other lactogenic hormones (human growth hormone, human placental lactogen, rat PRL), but not trophic nonlactogenic hormones (rat growth hormone, human chorionic gonadotropin, ACTH), also inhibited Dex (100 nM)-induced cytolysis. Agarose gel electrophoresis of DNA extracted from Nb2 cells revealed that within 12 hr, 100 nMDex induced DNA fragmentation, indicative of programmed cell death or apoptosis. Coincubation of cells with Dex and oPRL (1 ng/ml) inhibited Dexinduced fragmentation of Nb2 cell genomic DNA.These studies reveal a complex interaction between glucocorticoids and PRL in Nb2 cells. Although a glucocorticoid receptor-mediated antiproliferative effect is evident, PRL (at concentrations that usually stimulate cell proliferation) has the capacity to protect the cell against glucocorticoid-receptor-mediated induction of apoptosis.

Abstract. Cultured Nb2 node rat lymphoma cells require lactogenic hormone for their proliferation. We reported previously that dexamethasone (Dex) inhibits prolactin (PRL)-induced mitogenesis and, in the absence of mitogen, induces apoptosis of Nb2 cells. Both antiproliferative and cytolytic effects of Dex on Nb2 cells appear to involve glucocorticoid (Type II) receptor mediation. In this study, we compared Dex effects in PRL-dependent Nb2 cells (Nb2) with SFJCD1 (SF), a clone of Nb2 cells that proliferates independently of exogenous PRL. Proliferative assays involved a 72-hr incubation in a chemically defined, serum-free medium where ovine PRL (1 ng/ml) was added to Nb2 cells but not to SF cells. Both cell lines were responsive to the antiproliferative effects of Dex in a dose (6.25-200 nM)-dependent fashion of comparable sensitivity and magnitude. Co-incubation with the glucocorticoid receptor antagonist, RU 486, prevented the antiproliferative effect of Dex in both cell lines. In the same medium devoid of PRL, Dex was cytolytic to Nb2 cells and fragmented DNA in a fashion reflective of apoptosis, but was ineffective in SF cells. A dual chamber incubation system revealed no evidence that SF cells produced cytokines that were mitogenic or anticytolytic to Nb2 cells. Both Nb2 and SF cells fragmented DNA in a fashion indicative of apoptosis in the presence of the Ca2+ionophore, A23187 (1 μM). These studies reveal a basic difference in glucocorticoid responsiveness between the PRL-dependent Nb2 cell line and its PRL-independent subclone, SF. While both cell lines exhibit functional glucocorticoid receptors and the necessary intranuclear machinery for apoptosis, the pathway mediating the latter is inhibited or dysfunctional in SF cells. [P.S.E.B.M. 1993, Vol 203]

Adrenal 5α-reductase activity was measured in female rats 0, 2, 5, and 6 days after hypophysectomy. Enzyme activity increased progressively exhibiting a 35-fold elevation at 6 days. The effects of high (250 μg/100 g of body wt), intermediate (25 μg/ 100 g of body wt), and low (2.5 μg/100 g of body wt) daily doses of bovine prolactin and bovine growth hormone were compared at 2 and 5 days posthypophysectomy. At 2 days, enzyme activity was partially inhibited by the high and intermediate doses of prolactin and not affected by growth hormone. At 5 days all doses of prolactin were inhibitory, whereas enzyme activity was suppressed only by the high dose of growth hormone. With a given dose of hormone, the amount of suppression of enzyme activity is greater at 5 days than at 2 days posthypophysectomy. In 5-day hypophysectomized rats the inhibitory effects of prolactin and growth hormone were additive. It is concluded that: (i) hormonal sensitivity and responsiveness of the adrenal reductase pathway increases with duration of pituitary ablation; (ii) the reductase pathway is more sensitive to the effects of prolactin than growth hormone; and (iii) the effects of growth hormone and prolactin on reductase activity are mediated via different mechanisms, as suggested by the additive effects of individual hormones.

The application of the Phoroscope electrophoresis densitometer for the objective evaluation of immunoperoxidase-stained tissue sections at the light microscope level is described. The instrument directs a beam of light through the specimen (Kodachrome photomicrograph slides) and projects an absorbance pattern (as peaks and valleys) on an oscilloscope screen. The height of a peak is proportional to the optical density of a stained area, while the width of the peak is proportional to the diameter of an area. The utility of the densitometer was tested in sections of rat pituitary gland immunostained with NIAMDD antiserum against rat prolactin to reveal prolactin cells and sections of rat ventral prostate pretreated with NIAMDD rat prolactin and then immunostained to reveal Golgi region-localized prolactin binding sites in epithelial cells. The densitometer quantitated (by relative absorbance) the changes in immunostaining in serial sections of rat pituitary gland reacted with different dilutions of prolactin antiserum and in serial sections of rat ventral prostate pretreated with different concentrations of rat prolactin. In addition, the densitometric pattern provided information regarding the frequency and pattern of immunostaining within a particular microscopic field. Potential uses of an electrophoresis densitometer for the quantitation and standardization of immunohistochemistry are discussed.

In this presentation we discuss how male reproductive hormones are influenced by various normal and abnormal situations. Puberty is characterized by a progressive increase in serum gonadotropins (FSH and LH) and testosterone. Hormonal profiles in aging men and rats differ significantly, suggesting qualitatively different age-related changes in both species. Gonadal disorders in humans may exhibit similar symptoms (such as delayed or precocious virilization) but may be due to different defects within the hypothalamo-pituitary-testicular axis and, hence, may exhibit different reproductive hormone profiles. Reproductive hormone measurements reveal that toxic agents, such as ketoconazole, alcohol, or opiates, can impair reproductive function at the gonad and/or the hypothalamo-pituitary level. Glucocorticoids released during stress have been shown to have a direct inhibitory effect on testosterone release from the testes, which may be of relevance to toxicology studies. Reproductive hormonal measurements have also revealed that LH levels in the blood fluctuate in a pronounced episodic fashion and that this pattern is due to the pulsatile delivery of GnRH to the anterior pituitary gland. Administration of GnRH in a pulsatile fashion to patients with hypogonadotropic hypogonadism restores gonadal function. Nonpulsatile GnRH delivery to the anterior pituitary suppresses LH and testosterone release, and, consequently, long-acting superanalogs of GnRH appear to be effective in the treatment of prostatic cancer and true precocious puberty. The examples presented in this article illustrate how hormonal measurements have increased our knowledge and understanding of male reproduction.

In four cases of fungal meningitis, three due to Cryptococcus neoformans and one due to Coccidioides immitis, repeated doses of amphotericin B were given by needle injection into a subcutaneously placed, silicone-rubber reservoir attached to a catheter which passed through a burr-hole and the brain substance into a lateral ventricle (Ommaya reservoir). One patient with cryptococcal meningitis died of overwhelming infection after receiving amphotericin B, first intravenously and later by 15 injections into the reservoir. Two patients with cryptococcal and one with coccidioidal meningitis improved after amphotericin B treatment which included 21 to 74 injections into the reservoir.

Studies were conducted to further examine the interaction between gonadal hormones and ACTH in the regulation of adrenocortical function. Gonadectomy for a period of two weeks in pre-puberal rats of either sex or in adults for one week, was without effect on adrenal 5α-reductase activity and corticosterone production in vitro. Cortisone administration to intact rats, both before and after puberty, suppressed corticosterone and total steroid production and increased adrenal reductase activity. Ovariectomy in immature or adult females did not modify the effects of cortisone on adrenal function. Orchiectomy, both before and after puberty, synergistically enhanced the actions of cortisone to increase 5α-reductase activity and lower corticosterone production without affecting total steroid output. These observations lend support to the hypothesis that gonadal hormones interact with ACTH in the control of adrenocortical function. Adrenal 5α-reductase seems to be a common site of action for the effects.

Various physical conditions such as fasting (1-3), hypoxia (1), and exercise (2, 4) produce changes in myocardial glycogen concentrations that are superimposed upon the normal diurnal fluctuation of glycogen levels (5). The mechanisms by which these physiological conditions alter cardiac glycogen are not known. Although not all glycogen changes are dependent on the function of the adrenal glands (3, 6), glucocorticoids have been implicated as one regulatory substance of cardiac glycogen (6-8). The purpose of our study was to verify or dispel the proposed cause and effect relationship between glucocorticoid release and myocardial glycogen changes associated with physical exertion.Methods.Male adult Wistar strain rats were used in all the experiments and two-thirds of the rats were bilaterally adrenalectomized under Brevital anesthesia. The completeness of the adrenalectomies was verified by comparing plasma glucocorticoid levels in the adrenalectomized rats with those of hypophysectomized rats. All rats were fed ad lib.and the adrenalectomized rats were maintained on 0.9% NaCl drinking solution. Sham operated animals were used as controls. Half of the adrenalectomized rats were given dexamethasone phosphate, a synthetic glucocorticoid, intraperitoneally 20 μg twice daily.One week postoperation, rats were stressed by 15 min of swimming and then sacrificed at various times following the exercise. The animals were sacrificed with Brevital anesthesia since decapitation produces low glycogen levels (4). The thorax of each anesthetized rat was opened, the heart was removed rapidly (within 5-10 sec), and the resulting pool of blood in the thoracic cavity collected in a syringe. Total glycogen was extracted from whole hearts (9) and quantitatively determined by the anthrone method (10, 11). Plasma glucocorticoids were determined by the fluorescence procedure of Guillemin et al.(12). Data were analyzed by the analysis of variance and Duncan's multiple-range test under consultation with the department of Biometry.

• Sixteen patients underwent biopsy of primary or metastatic breast cancer and had equal portions of the tumors rapidly frozen by either the use of liquid nitrogen or the fluorinated hydrocarbon spray, Cryokwik. The estrogen receptor protein (ERP) assay was then performed on both specimens, utilizing the sucrose gradient density method. In general, both methods of freezing gave similar results. Three patients had ERP measured after approximately three to four months of storage at −70 C. After a minimum of 14 weeks' storage, there was no statistically significant loss of activity by either method of preparation.The Cryokwik preparation method makes the accurate measurement of ERP possible for all community hospitals. The tissue may be prepared and stored until a convenient time for transportation to the appropriate laboratory.(Arch Surg 112:183-185, 1977)

Four patients with cerebral tuberculomas had presenting manifestations that included seizure disorder, exophthalmos, or extremity weakness. Although rare in this country, this diagnosis should not be overlooked in such patients, since combined surgical and medical therapy may be curative.(JAMA 239:413-415, 1978)