Hormonal impact of the 17alpha-hydroxylase/C(17,20)-lyase inhibitor abiraterone acetate (CB7630) in patients with prostate cancer

A series of three dose escalating studies were conducted to investigate the ability of the 17α-hydroxylase/C_17,20-lyase inhibitor abiraterone acetate, to cause maximum suppression of testosterone synthesis when delivered to castrate and noncastrate males with prostate cancer. Study A was a single dose study in castrate males. Study B was a single dose study in noncastrate males and study C was a multiple dose study in noncastrate males. The drug was given orally in a once-daily dose and blood samples taken to assess pharmacokinetic (PK) parameters and hormone levels in all patients. The study drug was well tolerated with some variability in PKs. Suppression of testosterone levels to <0.14 nmol l⁻¹ was seen in four out of six castrate males treated with a single dose of 500 mg. At 800 mg given days 1–12 in noncastrate males, target suppression was achieved in three out of three patients, but a two- to three-fold increase of Luteinising Hormone (LH) levels in two out of three patients overcame suppression within 3 days. All patients in the multiple dose study developed an abnormal response to a short Synacthen test by day 11, although baseline cortisol levels remained normal. This is the first report of the use of a specific 17α-hydroxylase/_17,20-lyase inhibitor in humans. Repeated treatment of men with intact gonadal function with abiraterone acetate at a dose of 800 mg can successfully suppress testosterone levels to the castrate range. However, this level of suppression may not be sustained in all patients due to compensatory hypersecretion of LH. The enhanced testosterone suppression achieved in castrate men merits further clinical study as a second-line hormonal treatment for prostate cancer. Adrenocortical suppression may necessitate concomitant administration of replacement glucocorticoid.

Early pregnancy termination with mifepristone and misoprostol in the United States

BACKGROUND

Mifepristone and a prostaglandin have been used successfully to terminate pregnancy in Europe and China. We report the results of a large U.S. study of mifepristone and misoprostol in women with pregnancies of up to nine weeks' duration.

METHODS

We administered 600 mg of mifepristone and then 400 microg of misoprostol two days later to 2121 women seeking termination of their pregnancies at 17 centers. The women were observed for four hours after the administration of misoprostol and returned on day 15 for final assessment.

RESULTS

Two thousand fifteen women completed the final assessment. Among them, pregnancy was terminated in 762 of the 827 women pregnant for < or =49 days (92 percent), 563 of the 678 women pregnant for 50 to 56 days (83 percent), and 395 of the 510 women pregnant for 57 to 63 days (77 percent) (P<0.001). Termination occurred within 4 hours after the administration of misoprostol in 49 percent of the women and within 24 hours in 75 percent. Failures, defined as cases requiring surgical intervention for medical reasons or because the patient requested it, the abortion was incomplete, or the pregnancy was ongoing, increased with increasing duration of pregnancy. The largest increase was in failures representing ongoing pregnancy, which increased from 1 percent in the < or =49-days group to 9 percent in the 57-to-63-days group (P<0.001). Abdominal pain, nausea, vomiting, diarrhea, and vaginal bleeding also increased with advancing gestational age. Two percent of the women in the < or =49-days group, as compared with 4 percent in each of the other two groups, were hospitalized, underwent surgical interventions, and received intravenous fluids (P=0.008).

CONCLUSIONS

This mifepristone-misoprostol regimen is effective in terminating pregnancies, especially in women with pregnancies of 49 days' duration or less.

Regulation of simian virus 40 early transcription in vitro by a purified tumor antigen

Cloned DNA templates were used to direct the transcription of early and late simian virus 40 (SV40) genes by a cell-free RNA-synthesizing system. Transcription by RNA polymerase II was sensitive to low levels of alpha-amanitin and completely dependent on exogenously added DNA template. RNA products of discrete lengths were efficiently synthesized when transcription was directed by DNA restriction fragments containing promoter sequences for either early or late genes of SV40. Addition of the D2 tumor antigen to the template DNA inhibited transcription originating from the SV40 early promoter. In contrast, the D2 protein had little or no effect on the transcription from SV40 or adenovirus 2 (Ad2) late promoter sequences. When a mixture of cloned DNA containing SV40 early promoter and Ad2 late promoter was used to direct RNA synthesis, the D2 protein specifically inhibited the synthesis of SV40 early genes but not that of Ad2 late sequences. The D2 DNA binding protein also had no effect on the transcription directed by SV40 mutant templates that contain an intact early promoter sequence but lack specific tumor-antigen binding sites. We have confirmed that, under the conditions of the transcription assay, the D2 protein binds and interacts specifically with its recognition sites on wild-type template DNAs but fails to bind to mutant or Ad2 DNA templates that lack sequences containing SV40 tumor-antigen binding sites. These findings provide evidence that a direct interaction between tumor antigen and its specific binding sites on DNA is the mechanism by which the SV40 A gene autoregulates its transcription.

Enzymatic activities associated with a purified simian virus 40 T antigen-related protein

A protein antigenically related to the simian virus (SV 40) A gene product has been purified to near homogeneity from cells infected with the adenovirus-SV 40 hybrid virus Ad2(+)D2 and shown to contain ATPase (ATP phosphohydrolase, EC 3.6.1.3) and protein kinase (ATP:phosphotransferase, EC 2.7.1.37) activity. Both enzymatic activities copurify with the protein through six stages including one gel filtration column, two ion exchange columns, and a heparin affinity column. Analogous fractions from extracts of cells uninfected or infected with adenovirus 2 alone do not contain these enzymatic activities. The D2 hybrid protein resolves into two forms (I and II) during ion exchange chromatography. Form I, the major species (85%) of the D2 hybrid protein, elutes from DEAE-Sephadex in 0.37 M NaCl and is able to catalyze the hydrolysis of ATP to ADP + P(i) at a rate of 3 mumol/hr per mg. The remaining 10-15% of the D2 hybrid protein consists of form II which elutes from DEAE-Sephadex in 0.29 M NaCl and is able to hydrolyze ATP as well as to incorporate phosphorus from ATP into either the D2 hybrid protein itself or other protein acceptors such as phosvitin. Although both forms are able to bind DNA, the ATPase activity of form I cosediments with SV 40 DNA more efficiently than does the protein kinase activity of form II during glycerol gradient centrifugation. The ATPase activity of form I is efficiently inhibited by addition of anti-T gamma globulin to the reaction mixture whereas control gamma globulin has no effect. Similarly, the phosphorylation of the D2 hybrid protein by form II is inhibited by anti-T gamma globulin. By contrast, phosphorylation of phosvitin is specifically inhibited by antibody only when the immune complex is removed from the reaction mixture. Thus, it appears likely that one and possibly two enzymatic activities are carried out by the D2 hybrid protein. These findings are discussed in terms of mechanisms of SV 40 DNA replication and virally induced transformation.

Functional differences between afferent fibers in the hypogastric and pelvic nerves innervating female reproductive organs in the rat

1. The uterus, cervix, and vaginal canal are innervated by afferent fibers in the hypogastric and pelvic nerves. Four studies compared the innervation territory and sensitivity to peripheral stimuli of the two sets of fibers in adult virgin rats. 2. Innervation territory was studied anatomically by injecting different fluorescent dyes into different parts of the reproductive, lower urinary, and lower digestive tracts and examining retrogradely labeled neurons in dorsal root ganglia. It was also studied electrophysiologically in anesthetized rats by summing potentials evoked in branches of the two nerves by electrical stimulation of different parts of the reproductive tract. 3. In both studies sensory innervation of the reproductive tract shifted from the pelvic to the hypogastric nerve (i.e., shifted entry into the spinal cord from the L6-S1 to the T13-L3 dorsal root ganglia, respectively) as the dye or stimulating electrode shifted from the vaginal entrance to the uterine horns, with fibers from both nerves densely innervating the cervix region (i.e., entering the spinal cord through both sets of ganglia). The anatomic results suggested that the regions innervated by fibers in one nerve might also be innervated by a small component of normally quiescent fibers in the other nerve. 4. Response sensitivity was studied electrophysiologically by simultaneously recording multiunit activity in branches of the hypogastric and pelvic nerves in two ways. First, in intact, anesthetized rats, activity was recorded during mechanical stimulation of the reproductive tract (distension of the vagina and uterus, probing the cervix). Second, in an in vitro organ preparation of the uterus and vagina, activity was recorded during chemical stimulation through the uterine artery with bradykinin, serotonin, NaCN, CO2, and KCl. 5. Pelvic nerve fibers were markedly more sensitive than hypogastric nerve fibers to uterine and cervical mechanostimulation. Similarly, pelvic nerve fibers were more likely to respond or responded more vigorously than hypogastric nerve fibers to all chemical stimuli (except KCl). 6. These results provide strong evidence that afferent fibers in the pelvic and hypogastric nerves of nulliparous adult rats subserve different functions in reproduction and sensation. Pelvic nerve fibers seem closely tied to sensory and behavioral processes associated with mating and conception, whereas hypogastric fibers seem closely tied to pregnancy and nociception, with fibers in both nerves serving functions during parturition.

Afferent fibers supplying the uterus in the rat

1. In the present three-part study electrophysiological techniques were used to characterize responses of afferent fibers in the rat hypogastric nerve to mechanical or chemical stimulation of the uterus, and anatomical techniques were used to identify the spinal segments through which uterine afferent fibers enter the spinal cord. 2. In an in vivo barbiturate-anesthetized preparation, hypogastric afferent fibers responded in a time-locked manner to mechanical stimulation confined to restricted regions of the uterus and adjacent ligament. Receptive fields were most often located on the uterine body, particularly over the cervix. The few located on the uterine horn were usually near regions irritated during preparative surgery. Effective mechanical stimuli (pressure, stretching, squeezing, probing, rarely contractions) were typically greater than 5 g and simultaneously accompanied by transient ischemia around the probe or contracted area. Distension, unless extreme, was not an effective stimulus. Retrospective analysis of the data indicated that fibers may be more sensitive to uterine stimulation when rats are in vaginal estrus/proestrus than in diestrus/metestrus. 3. In an in vitro preparation, hypogastric afferent fibers responded in a dose-dependent fashion to injections into the uterine artery of the algesic chemicals bradykinin, 5-hydroxytryptamine, and KCl. They also responded to high doses of CO2 (in saline) and NaCN, but rarely to lower doses. Nearly all fibers responded to more than one chemical with response characteristics unique to each chemical (e.g., latency, duration, peak rate). 4. Injections of horseradish peroxidase into the uterine body and small portions of the adjacent horns in rats in vaginal estrus consistently labeled a small number of cells in the L1-S1 dorsal root ganglia, with peaks at L2 and L6. Virtually no cells were labeled in rats whose estrous cycle had been disrupted (by inadvertently keeping them in constant light conditions for several weeks). 5. These results indicate that uterine afferent fibers travel to the central nervous system through both the hypogastric (e.g., L1-L4 ganglia) and pelvic (e.g., L5-S1 ganglia) nerves in the rat, and that hypogastric fibers are capable of conveying fairly precise information about temporal and spatial aspects of uterine mechanical and chemical stimulation. The results also encourage future research into the possibility that the responses of these fibers vary as a function of estrous stage or other aspects of the condition of the uterus (e.g., its irritation).(ABSTRACT TRUNCATED AT 400 WORDS)

Contrast venography of the leg: diagnostic efficacy, tolerance, and complication rates with ionic and nonionic contrast media

A prospective, three-center study of two contrast agents for leg venography was performed to evaluate both the relative frequency of adverse effects and whether low-osmolality agents provided significant advantages for this procedure. Fifty-four patients were studied with the standard preparation (iothalamate meglumine) and 57 with a nonionic agent (iopamidol). Both were used at an iodine concentration of 200 mg/mL, and there were no differences in volume of contrast material, duration of infusion, percentage of positive studies, or overall diagnostic adequacy. Patient discomfort was less with iopamidol than with iothalamate (18% vs. 44%), although discomfort was generally mild in both groups. By objective follow-up studies, the frequency of postvenographic thrombosis was not significantly different in the two groups (8% vs. 9%). Contrast venography, then, had a low frequency of complications when either a dilute conventional or a low-osmolality agent was employed. Although the frequency of postvenographic thrombosis was low with both agents, patient discomfort was less with the low-osmolality formulation.

Identification of proteins that interact with a protein of interest: applications of the yeast two-hybrid system

The yeast two-hybrid system is a molecular genetic test for protein interaction. Here we describe a step by step procedure to screen for proteins that interact with a protein of interest using the two-hybrid system. This process includes, construction and testing of the bait plasmid, screening a plasmid library for interacting fusion proteins, elimination of false positives and deletion analysis of true positives. This procedure is designed to allow investigators to identify proteins and their encoding cDNAs that have a biologically significant interaction with your protein of interest.

Functional properties of afferent fibers supplying reproductive and other pelvic organs in pelvic nerve of female rat

1. Electrophysiological techniques were used to characterize responses of afferent fibers in pelvic nerve of adult, virgin female rats to mechanical or chemical stimulation of internal reproductive organs and to mechanical stimulation of other pelvic organs. 2. In an in vivo barbiturate-anesthetized preparation, pelvic nerve afferent fibers responded to a wide variety of mechanical stimulation applied to restricted regions of the vaginal canal, caudal uterus (body and cervix), bladder, ureter, colon, or anus. 3. Single-fiber mechanoreceptive fields were invariably confined to a single organ. Notably, responses could be evoked not only by gentle stimulation of the unit's receptive field directly on the organ itself, but also by stimulating the field indirectly with intense stimulation through the appropriate part of a contiguous organ. This innervation feature is consistent with the separability of pelvic organ functions under innocuous conditions but their confusion under noxious ones. 4. Receptive fields on the reproductive organs extended from the caudal edge of the vagina to the uterine body (including the cervix) but were most often located in the fornix (vaginocervical junction). Most units had no or low levels of spontaneous activity. Their responses to mechanical stimuli were usually slowly or moderately adapting and time-locked to the stimulus. 5. Fibers with vaginal receptive fields (including the fornix) responded best either to vaginal distension with a balloon or, more often, to a probe moving along the internal vaginal surface in a direction toward the cervix. They were observed most frequently during the proestrus stage of the rat's estrous cycle. These fibers, therefore, seem particularly suited for relaying information about stimuli that occur during mating. 6. Fibers with receptive fields on the uterine cervix and body responded best to static pressure and were observed less frequently than those with vaginal fields, regardless of estrous stage. They were, however, sensitized by hypoxia. In addition, irritation of the uterus increased the probability of observing them. These fibers, therefore, may exert their primary function during reproductive conditions different from those of virgin rats, such as parturition. 7. Response activity of most of the mechanoreceptive afferent fibers supplying reproductive organs increased as the stimulus intensity increased into the noxious range; i.e., into a range in which the stimulus momentarily produced ischemia at the stimulus site. In addition, in an in vitro preparation, pelvic nerve fibers responded in a dose-dependent manner to injections through the uterine artery of bradykinin (BRAD) as well as to other algesic chemicals, 5-hydroxytryptamine (5-HT) and KCl.(ABSTRACT TRUNCATED AT 400 WORDS)

A phase I trial of antibody directed enzyme prodrug therapy (ADEPT) in patients with advanced colorectal carcinoma or other CEA producing tumours

Antibody-directed enzyme prodrug therapy is a targeted therapy in which a prodrug is activated selectively at the tumour site by an enzyme, which has been targeted to the tumour by an antibody (antibody-enzyme conjugate). Previous clinical trials have shown evidence of tumour response, however, the activated drug had a long half-life, which resulted in dose-limiting myelosuppression. Also, the targeting system, although giving high tumour to blood ratios of antibody-enzyme conjugate (10 000 : 1) required administration of a clearing antibody in addition to the antibody-enzyme conjugate. The purpose of this current study therefore was to attempt tumour targeting of the antibody-enzyme conjugate without the clearing antibody, and to investigate a new prodrug (bis-iodo phenol mustard, ZD2767P) whose activated form is highly potent and has a short half-life. Twenty-seven patients were treated with antibody-directed enzyme prodrug therapy using A5CP antibody-enzyme conjugate and ZD2767P prodrug, in a dose-escalating phase I trial. The maximum tolerated dose of ZD2767P was reached at 15.5 mg m(-2)x three administrations with a serum carboxypeptidase G2 level of 0.05 U ml(-1). Myelosuppression limited dose escalation. Other toxicities were mild. Patients' quality of life was not adversely affected during the trial as assessed by the measures used. There were no clinical or radiological responses seen in the study, but three patients had stable disease at day 56. Human anti-mouse antibody and human anti-carboxypeptidase G2 antibody were produced in response to the antibody enzyme conjugate (A5CP). The antibody-enzyme conjugate localisation data (carboxypeptidase G2 enzyme levels by HPLC on tumour and normal tissue samples, and gamma camera analysis of I-131 radiolabelled conjugate) are consistent with inadequate tumour localisation (median tumour: normal tissue ratios of antibody-enzyme conjugate of less than 1). A clearance system is therefore desirable with this antibody-enzyme conjugate or a more efficient targeting system is required. ZD2767P was shown to clear rapidly from the circulation and activated drug was not measurable in the blood. ZD2767P has potential for use in future antibody-directed enzyme prodrug therapy systems.

Estrous cycle variation of afferent fibers supplying reproductive organs in the female rat

Multi-unit afferent nerve activity was recorded from branches of the hypogastric and pelvic nerves in virgin female rats on different days of the estrous cycle. In each rat, the response of hypogastric nerve fibers to uterine distension and the response of pelvic nerve fibers to vaginal distension was tested. The minimal pressure necessary to evoke a response was highest in diestrus for both the hypogastric and pelvic nerve fibers. For the hypogastric nerve, the minimal necessary pressures were significantly lower during both proestrus and estrus, whereas for the pelvic nerve, the pressure was significantly lower only on the day of proestrus. These results suggest that the overall response sensitivity of afferent fibers in the pelvic and hypogastric nerves are differentially affected by hormonal variations occurring across the estrous cycle in a manner that would enhance reproduction.

Infusions of diazepam and allopregnanolone into the midbrain central gray facilitate open-field behavior and sexual receptivity in female rats

We have previously shown that blocking GABAA receptors with bicuculline in the dorsal and lateral quadrants of the rostral two-thirds of the midbrain central gray (MCG) in rats reduces the lordosis quotient (LQ) and proceptive behaviors without increasing the defensive index (McCarthy, Pfaff, and Schwartz-Giblin, 1991b), indicating that tonic release of endogenous GABA in the MCG has a primary facilitatory effect on reproductive behaviors. The present study tests whether two modulators of the GABAA-benzodiazepine-receptor complex, diazepam and the progesterone metabolite, allopregnanolone, facilitate female receptivity as well as open-field behavior. Ovariectomized estradiol benzoate (EB)-treated rats were bilaterally infused in the MCG with vehicle, diazepam, or allopregnanolone and tested 20 min after diazepam and 12 min after allopregnanolone. Animals were tested once each for both receptive or open-field behavior with testing sessions being at least 1 week apart in a crossover design between vehicle and one of the two drugs. Both diazepam and allopregnanolone significantly increased the lordosis quotient in a dose-dependent manner, the lowest effective dose tested being 100 and 250 ng, respectively. In the open-field test, infusion of diazepam (100 ng) in EB-treated rats significantly increased the ratio of central squares entered to total squares entered (C/T) without a change in total activity. Rats without EB elicited comparable C/T ratios when tested with five times as much diazepam. Diazepam infusions at more dorsal sites in the midbrain and in overlying cortex were without effect on C/T ratios in EB-treated rats. Allopregnanolone (500 ng) infusions in MCG of EB-treated rats did not alter C/T ratios compared to animals without EB. Our results are consistent with diazepam and allopregnanolone acting through the GABAA receptors of the MCG to enhance female sexual receptivity and with estradiol potentiating the effect of diazepam in the MCG to increase open-field behavior.

Measuring physicians' humanistic attitudes, values, and behaviors

This paper describes the reliability and validity of 10 easily administered and scored self-report measures of physicians' humanistic attitudes, values, and behaviors. This research also provides evidence that evaluations of physicians' humanistic behavior made by their outpatients, and non-physician staff with whom they worked, and the faculty physicians supervising them on inpatient ward rotations were positively and significantly correlated with one another. The potential usefulness of a multi-modal approach in evaluating humanistic physician attributes in which self-report measures are combined with direct feedback from all of those who interact with physicians is discussed.

Antiprogestins: mechanism of action and contraceptive potential

Antiprogestins are characterized by substitutions at the 11 beta and 17 alpha positions of the steroid ring system and bind strongly to both progesterone and glucocorticoid receptors. Although they function predominantly as antiprogestins and antiglucocorticoids, on occasion they display progestin agonistic and even antiestrogenic properties. The most common clinical use of the antiprogestin mifepristone is to induce a medical abortion in the early stages of pregnancy. Progesterone maintains the endometrium, transforming it from a proliferative to a secretory state. It also facilitates the luteinizing hormone surge, which initiates ovulation. As a consequence, antiprogestins may also have contraceptive potential. Although antiprogestins do delay ovulation, this effect is inconsistent unless high doses are given, and under these circumstances, the antiprogestin effect is associated with unopposed estrogen action on the endometrium. Very low doses of antiprogestins do not affect hormonal secretion or ovulation or alter bleeding patterns, but they do have contraceptive potential by inducing profound alterations in endometrial morphology. Mifepristone is also a very effective and safe postcoital agent. This new class of pharmacological agents has numerous other gynecological and obstetrical indications, such as endometriosis, uterine myoma, and expulsion of the fetus in the case of fetal death in utero. Antiprogestins may also be used in the treatment of steroid-dependent tumors. There are also therapeutic implications consequent to their antiglucocorticoid properties.

Evaluation of docking/scoring approaches: a comparative study based on MMP3 inhibitors

An increasing number of docking/scoring programs are available that use different sampling and scoring algorithms. A reliable scoring function is the crucial element of such approaches. Comparative studies are needed to evaluate their current capabilities. DOCK4 with force field and PMF scoring as well as FlexX were used to evaluate the predictive power of these docking/scoring approaches to identify the correct binding mode of 61 MMP-3 inhibitors in a crystal structure of stromelysin and also to rank them according to their different binding affinities. It was found that DOCK4/PMF scoring performs significantly better than FlexX and DOCK4/FF in both ranking ligands and predicting their binding modes. Most notably, DOCK4/PMF was the only scoring/docking approach that found a significant correlation between binding affinity and predicted score of the docked inhibitors. However, comparing only those cases where the correct binding mode was identified (scoring highest among sampled poses), FlexX showed the best 'fine tuning' (lowest rmsd) in predicted binding modes. The results suggest that not so much the sampling procedure but rather the scoring function is the crucial element of a docking program.

Site-specific insertion of DNA into a pseudorabies virus vector

A simple, efficient method for introducing recombinant DNA into a herpesvirus vector and retrieving it at a later time has been developed. By using the Cre-lox site-specific recombination system of coliphage P1, DNA can be readily inserted in vitro into a pseudorabies virus (PRV) vector containing the lox recombination site. The vector PRV42 contains a lox site within the nonessential gIII gene, which encodes a virion envelope glycoprotein. Incubation in vitro of PRV42 DNA with Cre protein and a circular plasmid containing a lox site generates approximately 5% recombinant molecules having the plasmid integrated into the PRV genome at the lox site. Transfection of the reaction mixture into cultured cells allows recovery of the infectious recombinant virus, which is readily identified by a nondestructive "black-plaque assay" using a gIII-specific monoclonal antibody. PRV42 plaques stain black when treated with the gIII monoclonal antibody and a peroxidase-linked second anti-antibody because the lox site placed within the gIII gene of PRV42 does not destroy the gIII epitope. However, Cre-mediated integration of heterologous DNA at the lox site disrupts the gIII epitope so that the resulting recombinant virus produces white plaques. The recombinant virus is infectious, stable, and grows as well as the parental PRV42 vector. The inserted plasmid can be efficiently excised (greater than 50%) from viral DNA by Cre and recovered by transformation of Escherichia coli.

A phase II trial of bryostatin 1 in patients with non-Hodgkin's lymphoma

Bryostatin 1 is a naturally occurring macrocyclic lactone with promising antitumour and immunomodulatory function in preclinical and phase I clinical investigations. In this phase II study, 17 patients with progressive non-Hodgkin's lymphoma of indolent type (NHL), previously treated with chemotherapy, received a median of 6 (range 1-9) intravenous infusions of 25 microg/m(2) bryostatin 1 given once weekly over 24 hours. In 14 evaluable patients no responses were seen. Stable disease was attained in one patient for 9 months. The principal toxicities were myalgia and phlebitis. Treatment was discontinued early because of toxicity alone (phlebitis) in 2 patients, toxicity in addition to progressive disease in 3 patients (myalgia and phlebitis n = 2; thrombocytopenia n = 1) and progressive disease in 5 patients. The results fail to demonstrate efficacy of this regimen of bryostatin 1 in the treatment of NHL. In light of preclinical data that demonstrate synergy between bryostatin 1 and several cytotoxic agents and cytokines, clinical studies to investigate bryostatin 1 in combination are warranted. We also present data to demonstrate that central venous lines may be used in future studies to avoid phlebitis.

Reproducibility of a self-administered diet history questionnaire administered three times over three different seasons

The reproducibility of the widely used Health Habits and History Questionnaire (HHHQ) for estimating "usual past-year" nutrient intake was examined. The HHHQ was self-administered on three occasions during three different seasons; 68 women (avg age 43 yrs) provided usable data for all three questionnaires in the appropriate seasons. Intraclass correlations (ICC) among the three administrations ranged from 0.56 (carotene) to 0.82 (fat as percentage of energy), with a median of 0.72. Thus, reliability was moderate to good, and season of administration/ordinality generally had little impact on ranking of individuals. The point estimates of intake of energy and a number of nutrients were higher in the first administration (winter). Except for dietary fiber and possibly carotene, most differences disappeared when adjusted for energy using a nutrient density approach, as well as using repeated-measures regression models. The higher intake in the first administration may be due more to either learning or fatigue effect rather than an effect of seasonal food availability on perceptions of "usual" intake. These data should be used in conjunction with validity data in the future to help evaluate the gain in precision of group means (and changes in these means) and improved estimates of odds ratios and correlations between nutrients and factors such as serum values, if a questionnaire is administered more than once.

Responses of hypogastric nerve afferent fibers to uterine distension in estrous or metestrous rats

The response of afferent fibers in the distal end of the cut hypogastric nerve to distension of the uterus to various pressure levels was investigated in anesthetized virgin female rats on two different days of the estrous cycle (estrus or metestrus). Whereas relatively intense levels of uterine distension produced an increase in afferent activity in a pressure-dependent manner in both stages of the estrous cycle, the minimal pressure necessary to activate the fibers was significantly less on the day of estrus. These results suggest that hypogastric nerve afferent fibers are more likely to respond to potentially damaging uterine stimuli during the time when such responsiveness would be most important for reproductive success.

Effects of testosterone and 7 alpha-methyl-19-nortestosterone (MENT) on sexual and aggressive behaviors in two inbred strains of male mice

Behavioral and endocrine effects of a synthetic androgen, 7 alpha-methyl-19-nortestosterone (MENT), which is not 5 alpha-reduced to dihydrotestosterone, were compared to those of testosterone in two inbred strains of male mice, C57BL/6J and DBA/2J, in two experiments. In the first experiment, seminal vesicle (SV) weights, kidney weights, and circulating steroid levels were examined in castrated mice treated with three doses of testosterone (3.125, 12.5, or 50 micrograms/day) or four doses of MENT (1, 4, 16, or 64 micrograms/day) for 2 weeks to determine the optimal replacement levels of the two androgens for behavioral studies. Both testosterone and MENT dose-dependently increased the SV weights that were greatly reduced, in both strains, by castration. MENT was more effective than testosterone in increasing SV weights, fully restoring them to intact levels in both strains, at the dose of 4 micrograms/day. At the dose of 12.5 micrograms/day, testosterone restored the SV weights completely in C57BL/6J and up to 80% in DBA/2J mice. DBA/2J mice were more sensitive than C57BL/6J mice to both androgens, as measured by kidney weights, although circulating levels of either steroid were very similar between the two strains of mice. In the second experiment, we investigated the effects of testosterone (12.5 micrograms/day) and MENT (4 micrograms/day) on sexual and aggressive behaviors. In each strain, MENT-treated and testosterone-treated mice showed similar numbers of mounts or intromissions. MENT was equally effective as testosterone to fully (C57BL/6J) or partially (DBA/2J) restore sexual behaviors as well as the SV weights to the intact levels. In contrast, MENT-treated mice of both strains were much less aggressive than testosterone-treated mice. In both C57BL/6J and DBA/2J mice, testosterone fully restored aggression to the intact levels as measured by aggression latency, number of aggressive bouts, and duration of aggression, whereas aggressive behaviors of the MENT-treated groups were not different from those of the castrated control groups. These results suggest that MENT can restore both male sexual behaviors and reproductive organ weights as effectively as testosterone, at one-third of the testosterone dose, without stimulating male aggressive behaviors.

Ascending and descending projections to medullary reticular formation sites which activate deep lumbar back muscles in the rat

The purpose of this study was to determine ascending and descending afferents to a medullary reticular formation (MRF) site that, when electrically stimulated, evoked EMG activity in lumbar deep back muscles. In anesthetized female rats, the MRF was explored with electrical stimulation, using currents less than 50 microA, while EMG activity was recorded from the ipsilateral lateral longissimus (LL) and medial longissimus (ML). MRF sites that evoked muscle activity were located in the gigantocellular nucleus (Gi). At the effective stimulation site, the retrograde fluorescent tracer, Fluoro-Gold (FG), was deposited via a cannula attached to the stimulating electrode. In matched-pair control experiments, FG was deposited at MRF sites that were ineffective in producing EMG activity in LL and ML, for comparison of afferent projections to effective versus ineffective sites. Labeled cells rostral to FG deposition at effective MRF sites were located in the preoptic area, hypothalamus, limbic forebrain and midbrain, with particularly high numbers in the ipsilateral midbrain central gray, tegmentum, paraventricular nucleus and amygdala. At medullary levels, there was a heavy projection from the contralateral Gi. FG labeled cells were also located in the contralateral parvocellular reticular nucleus, and lateral, medial and spinal vestibular nuclei. Labeled cells with ascending projections were observed in greatest number in the rostral cervical spinal cord, with fewer cells at mid cervical levels and even fewer in the lumbar spinal cord. These labeled cells were located primarily in lamina V, VII, VIII and X. Locations of labeled cells following FG deposition at ineffective MRF sites were similar. However, there was a striking difference in the number of cells retrogradely labeled from the effective MRF sites compared to ineffective MRF sites. Significantly greater numbers of labeled cells were observed in the contralateral MRF, the midbrain, and the cervical spinal cord from the FG deposition at effective stimulation sites. These results suggest that one characteristic of MRF sites that activate epaxial muscles is a larger amount of afferent input, from the midbrain central gray and from contralateral Gi, compared to ineffective MRF sites. Ascending and descending inputs converge at the effective MRF sites, and the larger number of descending projections suggests a more powerful contribution of these afferents to deep lumbar back muscle activation.

Differential effects of high fat diet and diet-induced obesity on skeletal acquisition in female C57BL/6J vs. FVB/NJ Mice

The effects of obesity on bone metabolism are complex, and may be mediated by consumption of a high fat diet and/or by obesity-induced metabolic dysregulation. To test the hypothesis that both high fat (HF) diet and diet-induced metabolic disease independently decrease skeletal acquisition, we compared effects of HF diet on bone mass and microarchitecture in two mouse strains: diet-induced obesity (DIO)-susceptible C57BL/6J (B6) and DIO-resistant FVB/NJ (FVB). At 3 wks of age we weaned 120 female FVB and B6 mice onto normal (N, 10% Kcal/fat) or HF diet (45% Kcal/fat) and euthanized them at 6, 12 and 20 weeks of age (N = 10/grp). Outcomes included body mass; percent fat and whole-body bone mineral density (WBBMD, g/cm2) via DXA; cortical and trabecular bone architecture at the midshaft and distal femur via μCT; and marrow adiposity via histomorphometry. In FVB HF, body mass, percent body fat, WBBMD and marrow adiposity did not differ vs. N, but trabecular bone mass was lower at 6 wks of age only (p < 0.05), cortical bone geometric properties were lower at 12 wks only, and bone strength was lower at 20 wks of age only in HF vs. N (p < 0.05). In contrast, B6 HF had higher body mass, percent body fat, and leptin vs. N. B6 HF also had higher WBBMD (p < 0.05) at 9 and 12 wks of age but lower distal femur trabecular bone mass at 12 wks of age, and lower body mass-adjusted cortical bone properties at 20 wks of age compared to N (p < 0.05). Marrow adiposity was also markedly higher in B6 HF vs. N. Overall, HF diet negatively affected bone mass in both strains, but was more deleterious to trabecular bone microarchitecture and marrow adiposity in B6 than in FVB mice. These data suggest that in addition to fat consumption itself, the metabolic response to high fat diet independently alters skeletal acquisition in obesity.