Discriminative stimulus properties of psychomotor stimulants in the cat

Cats were trained to choose between two levers of an operant chamber using interoceptive cues provided by d-amphetamine or saline as the discriminative stimuli. Following training, stimulus generalization was observed to additional doses of d-amphetamine and cocaine, but not to morphine. Clozapine blocked the generalization of the drug discrimination response to d-amphetamine, but had no effect on generalization to cocaine. These data indicate that discriminative stimulus properties of psychomotor stimulants, previously described in rats, are similar in cats.     

An initial report of a radiation dose-escalation trial in patients with one to five sites of metastatic disease

PURPOSE: Previous investigations have suggested that a subset of patients with metastatic cancer in a limited number of organs may benefit from local treatment. We investigated whether cancer patients with limited sites of metastatic disease (oligometastasis) who failed standard therapies could be identified and safely treated at one to five known sites of low-volume disease with radiotherapy. EXPERIMENTAL DESIGN: Patients with one to five sites of metastatic cancer with a life expectancy of >3 months and good performance status received escalating doses of radiation to all known sites of cancer with hypofractionated radiation therapy. Patients were followed radiographically with computed tomography scans of the chest, abdomen, and pelvis and metabolically with [18F]fluorodeoxyglucose-positron emission tomography 1 month following treatment and then every 3 months. Acute toxicities were scored using the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0 and late toxicities were scored using the Radiation Therapy Oncology Group late toxicity scoring system. RESULTS: Twenty-nine patients with 56 metastatic lesions were enrolled from November 2004 to March 2007, with a median follow-up of 14.9 months. Two patients experienced acute (radiation pneumonitis and nausea) and one experienced chronic (gastrointestinal hemorrhage) grade > or =3 toxicity. Fifty-nine percent of patients responded to protocol therapy. Twenty-one percent of patients have not progressed following protocol treatment. Fifty-seven percent of treated lesions have not progressed at last follow-up. Progression was amenable to further local therapy in 48% of patients. CONCLUSIONS: Patients with low-volume metastatic cancer can be identified, safely treated, and may benefit from radiotherapy.     

Factors relevant to mode of preterm delivery with syndrome of HELLP (hemolysis,elevated liver enzymes,and low platelets)

OBJECTIVE: Our purpose was to investigate factors relevant to mode of delivery for patients with preterm (<34 weeks) gestation complicated by the syndrome of hemolysis, elevated liver enzymes, and low platelets (HELLP). STUDY DESIGN: The pregnancies of 189 patients with HELLP syndrome and delivery <34 weeks' gestation between January 1980 and October 1991 were studied retrospectively. Only patients with class 1 (platelet nadir ≤50,000 per microliter, n = 83) and class 2 (platelet nadir >50,000 to ≤100,000 per microliter, n = 106) HELLP syndrome were included. Maternal and perinatal factors relevant to type of delivery were reviewed. RESULTS: The incidence of cesarean delivery for all patients was 76.2% (primary rate 72.4%). Abdominal delivery occurred equally between class 1 (78.3%) and class 2 (74.5%) patients. Cesarean section was the mode of delivery for 87% of pregnancies at <30 weeks' gestation in contrast to 68% of pregnancies at≥30 weeks but <34 weeks' gestation (odds ratio 3.2, 95% confidence interval 1.4 to 7.5, p < 0.005). Indications for cesarean section included deteriorating maternal condition alone (50%), deteriorating maternal and fetal condition (27%), nonvertex fetal presentation (11.5%), and failure to progress (11%). Induction of labor was significantly more successful during the≥30 but <34 weeks' pregnancy interval (47.5%) than in pregnancies at <30 weeks (15.2%) (odds ratio 0.2, 95% confidence interval 0.1 to 0.55, p < 0.001). A trial of labor was successful in 22% of patients with an initial modified Bishop score ≤2 versus 45% with an initial Bishop >2 (odds ratio 0.5, 95% confidence interval 0.2 to 1.3, p = 0.16). CONCLUSION: Parturients with class 1 and 2 HELLP syndrome at <34 weeks' gestation are at high risk for cesarean delivery. At a gestational age <30 weeks, the likelihood of successful labor induction with vaginal delivery is remote, especially in association with an unfavorable cervix or the absence of labor. (AM J Obstet Gynecol 1994;170:1828-34.)     

Colposcopic genital findings in prepubertal girls assessed for sexual abuse

After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management.     

Cervical ripening before medical induction of labor: a comparison of prostaglandin E, estradiol, and oxytocin

Objective: Our purpose was to evaluate the effectiveness of oxytocin, prostaglandin, E² intracervical gel, and estradiol cream for ripening the very unfavorable cervix in patients requiring induction of labor at term.Study design: This prospective, randomized study was conducted in a population of women with a very unfavorable cervix (Bishop score <4) requiring induction of labor. The patients received prostaglandin E² gel (0.5 mg) intravervically (three doses 6 hours apart), 4 mg estradiol cream in the anterior fornix of the vagina (three doses 6 hours apart), or oxytocin at induction per protocol with an infusion pump.Results: Ninety-nine women were recruited into this trial and evenly distributed among the three groups. The demongraphics of maternal age, race, parity, gestational age, initial Bishop score, and indication for induction were similar among the groups. The incidence of cesarean deliveries was similar in the three groups with approximately 59% of pregnancies delivered abdominally. For patients undergoing abdominal delivery the maximum cervical dilatation among the oxytocin, estradiol, and prostaglandin E² groups was similar (3.90 = 3.02 cm, 3.63 ± 2.79 cm, and 4.65 ± 2.78 cm, respectively; p > 0.05). For all patients birth weight and Apgar scores at 1 and 5 minutes were comparable across all regimens (p > 0.05). In the subset of patients delivered vaginally patients receiving oxytocin for cervical ripening had the greatest improvement on Bishop score over baseline (p = 0.023) with an improvement of 7.08 ± 2.42.Conclusion: No differences were detected among prostaglandin E₂ gel, estrogen, and oxytocin in relation to cervical ripening in patients with an unfavorable cervix at term who require an induction of labor. Patients with a very unfavorable cervix at term who require delivery may benefit from serial ripening and inductions.     

Screening for amblyopia in preverbal children with photoscreening photographs. III. improved grading criteria for hyperopia

OBJECTIVE: To examine the ability of the Medical Technology and Innovations (MTI), Inc., Photoscreener (Cedar Falls, IA) to detect hyperopia and to improve the photograph grading criteria to screen for amblyopiogenic levels of hyperopia. DESIGN: Cross-sectional study and reanalysis. PARTICIPANTS AND TESTING: In previous work, 392 participants received a complete ophthalmologic examination and were photographed using the MTI Photoscreener. For this study, all 209 participants with normal examination findings (65 children) or hyperopia without anisometropia (144 children) were selected. The data were reanalyzed using modified photograph grading and ophthalmologic examination failure criteria. Potential reasons for why many children with hyperopia passed photoscreening were explored. MAIN OUTCOME MEASURES: We determined whether a study participant would pass or fail screening with a given photograph grading and ophthalmologic examination failure criteria. RESULTS: Most children with hyperopia of +2.00 to +3.50 diopters (D) passed screening with the MTI instrument, in most cases because their photographs lacked bright crescents. When bright crescents in at least two of the four possible meridians were the grading guideline for screening failure and the pediatric ophthalmologists' consensus hyperopia failure criteria (> +3.50 D) were adopted, the sensitivity for hyperopia detection was 100% and the specificity was 88%. Identical results were obtained using the American Academy of Ophthalmology Preferred Practice Pattern hyperopia failure criteria (>/= +4.50 D). CONCLUSIONS: The MTI photograph grading guidelines can be simplified, and the ophthalmologic examination failure criteria for hyperopia can be improved. The presence of a bright crescent in the lower or the left pupillary margin indicate hyperopia in an amblyopiogenic range (> +3.50 D).     

Serum CA 125 and survival of mice inoculated with ovarian carcinoma and treated with antiestrogen, estrogen, or progestin

The human ovarian carcinoma cell line NIH-OVCAR-3 grown in immunodeficient mice has been reported to be sensitive to estrogen medications and to express progestin receptor. To assess the effects of sex steroids on CA 125 production and survival times in these mice, we administered Tamoxifen, estrogen, and progestin. During the first 28 days after inoculation of mice with 2.3 million tumor cells ip, serum CA 125 rose exponentially, reaching 4308 +/- 776 and 3905 +/- 1013 units/ml (mean +/- SEM, P greater than 0.1) in placebo- and Tamoxifen-treated mice, respectively; median survival times were 41 and 39 days, respectively (P greater than 0.1). Uninoculated mice had nondetectable CA 125, and all outlived the inoculated mice. In tumor-inoculated mice, serum CA 125 levels and survival were similar when estrogen or progestin was injected alone and when both were given in combination. We detected no significant differences in production of CA 125 in vitro by tumor cells harvested from ascites fluid when the mice were treated with placebo, estrogen, or progestin. We conclude that, for our model, serial measurements of serum CA 125 provide excellent estimates of the relationship between tumor burden and survival, and that CA 125 production appears unaffected by estrogen, progestin, or Tamoxifen.     

Complications of general anesthesia using nitrous oxide in eyes with preexisting gas bubbles

PURPOSE: To present the visual and anatomical outcomes for patients with intraocular gas placed during vitreoretinal surgery who subsequently underwent surgery wherein general anesthesia with nitrous oxide was used. METHODS: The authors reviewed the charts of patients who had undergone vitreoretinal surgery where a long-acting gas tamponade had been used. These patients underwent additional surgery for a variety of reasons at five different institutions and had nitrous oxide used during general anesthesia. The authors reviewed the preoperative and postoperative findings for patients receiving nitrous oxide following vitreoretinal surgery with gas tamponade. RESULTS: The authors reviewed findings for five eyes of five patients. All eyes that underwent general anesthesia using nitrous oxide had significant preexisting intraocular gas bubbles ranging from 40% to 90%, and the surgical procedures lasted from 1 to 4 hours. These eyes were followed from 2 months to 9 years (median follow-up, 4 years). Four of five eyes had a final vision of 20/200 or worse and significant optic atrophy at the time of the last follow-up examination. Three eyes had no light perception. CONCLUSION: The use of nitrous oxide during general anesthesia in gas-filled eyes may have disastrous visual results caused by gas expansion and elevated intraocular pressure. Patients must be advised of the potentially catastrophic results of undergoing general anesthesia before their intraocular gas bubble has resorbed. The use of nitrous oxide for patients with intraocular gas should be avoided. It may be prudent for patients with intraocular gas to wear notification bracelets warning anesthesiologists about the presence of intraocular gas lest emergency surgery be needed by a patient unable to advise anesthesia personnel about the potential danger.     

Behavioral sensitization is greater after repeated versus single chronic cocaine dosing regimens

Phencyclidine (PCP) rapidly (within 1 h) increased vesicular dopamine uptake and binding of the vesicular monoamine transporter-2 (VMAT-2) ligand, dihydrotetrabenazine. Uptake returned to basal values 3 h in the striatum after a high-dose administration of this drug (15 mg/kg i.p.). In contrast, a similar pretreatment with another non-competitive NMDA receptor antagonist, dizocilpine;([5R,10S]-[+]-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine; MK-801; 1 mg/kg, i.p.), was without effect on vesicular dopamine uptake. Pretreatment with the dopamine D2 receptor antagonist, eticlopride, blocked the increase in vesicular dopamine uptake caused by PCP administration. These data demonstrate a heretofore unreported mechanism that may contribute to the ability of PCP to influence dopamine neuronal function and exert its pharmacological effects.