Hypoxia stimulates the synthesis of cytochrome P450-derived inflammatory eicosanoids in rabbit corneal epithelium

The corneal epithelium metabolizes arachidonic acid by a cytochrome P450-(CYP) mediated pathway to 12(R)hydroxy-5,8,10,14-eicosatrienoic acid [12(R)-HETE] and 12(R)hydroxy-5,8,14-eicosatrienoic acid [12(R)-HETrE]. Both metabolites possess potent inflammatory properties with 12(R)-HETrE being a powerful angiogenic factor and assume the role of inflammatory mediators in hypoxia- and chemical-induced injury in the cornea, in vivo. We developed an in vitro model of corneal organ culture to characterize the biochemical and molecular events involved in the increased synthesis of these metabolites. These cultured corneas exhibit epithelial cytochrome P450 CYP-dependent 12(R)-HETE and 12(R)-HETrE synthesis as indicated by chiral analysis and by the ability of CYP enzyme inhibitors to repress their synthesis. Hypoxia greatly and selectively stimulated the synthesis of 12(R)-HETE (7-fold over control normoxic conditions) and 12(R)-HETrE. The bacterial endotoxin, lipopolysaccharide, also increased the synthesis of these eicosanoids, substantiating the notion that this activity may function as an inflammatory pathway. These metabolites were detected in the culture medium by gas chromatography/mass spectroscopy (GC/MS) analysis and their levels significantly increased in hypoxia-treated corneas, further indicating their endogenous formation in response to injury. This in vitro model provides an excellent preparation for studying factors regulating the synthesis of these inflammatory eicosanoids and for isolating, identifying and characterizing the CYP protein responsible for their synthesis.

The orphan seven-transmembrane receptor apj supports the entry of primary T-cell-line-tropic and dualtropic human immunodeficiency virus type 1

Human immunodeficiency virus type 1 (HIV-1) enters target cells by sequential binding to CD4 and specific seven-transmembrane-segment (7TMS) coreceptors. Viruses use the chemokine receptor CCR5 as a coreceptor in the early, asymptomatic stages of HIV-1 infection but can adapt to the use of other receptors such as CXCR4 and CCR3 as the infection proceeds. Here we identify one such coreceptor, Apj, which supported the efficient entry of several primary T-cell-line tropic (T-tropic) and dualtropic HIV-1 isolates and the simian immunodeficiency virus SIVmac316. Another 7TMS protein, CCR9, supported the less efficient entry of one primary T-tropic isolate. mRNAs for both receptors were present in phytohemagglutinin- and interleukin-2-activated peripheral blood mononuclear cells. Apj and CCR9 share with other coreceptors for HIV-1 and SIV an N-terminal region rich in aromatic and acidic residues. These results highlight properties common to 7TMS proteins that can function as HIV-1 coreceptors, and they may contribute to an understanding of viral evolution in infected individuals.

Osteoporosis and coronary atherosclerosis in asymptomatic postmenopausal women

Estrogen deficiency is a risk factor for osteoporosis and coronary artery disease. Osteoporosis can be evaluated by measuring bone mineral density (BMD). Coronary atherosclerotic burden can be evaluated by measuring coronary calcium using electron beam computed tomography (EBT) of the heart. We compared coronary calcium scores in 45 asymptomatic postmenopausal women with normal and low BMD. BMD of the lumbar spine and proximal femur was measured by dual X-ray absorptiometry (DXA), and coronary calcium was measured quantitatively by EBT. Women were divided into control, osteopenia, and osteoporosis groups based on the T score of the lumbar spine. Women were similar in age, years since menopause, height, weight, and body mass index (BMI). BMD +/- SD (g/cm2) of L1-L4 was 0.96 +/- 0.11, 0.83 +/- 0.03, and 0.73 +/- 0.05, in control, osteopenia, and osteoporosis group, respectively. The total coronary calcium score +/- SD (relative units) was 41.9 +/- 83.1, 115.1 +/- 181.9, and 221.7 +/- 355.4 for control, osteopenia, and osteoporosis group, respectively; the score was significantly higher in the osteoporosis than in the control group. This study provides initial data suggesting that women with osteoporosis may have a higher risk of developing coronary atherosclerosis.

Value of preoperative CA 125 level in the management of uterine cancer and prediction of clinical outcome

OBJECTIVE

To enhance cost-effective management of uterine cancer by predicting the likelihood of extrauterine disease and survival on the basis of preoperative parameters.

METHODS

A retrospective review of preoperative CA 125 levels from 210 women with endometrial carcinoma was performed. The relationship of preoperative CA 125 levels to various preoperative and postoperative histopathologic factors was investigated.

RESULTS

Elevated CA 125 (greater than 35 U/mL) correlated (P < .05) with higher stage, higher grade, increased depth of myometrial invasion, positive cytology, pelvic or para-aortic lymph node metastases, and reduced actuarial survival (P < .001). Multivariate analysis of preoperative factors showed that an elevated CA 125 level was the most important predictor for poor survival (P < .001). Moreover, a preoperative CA 125 level greater than 65 U/mL was the most significant predictor of extrauterine disease and carried a 6.5-fold higher risk (95% confidence interval 2.5, 17.1). A logistic model to predict extrauterine disease was developed. The model has a sensitivity of 62%, specificity of 91%, positive predictive value of 69%, and negative predictive value of 88%.

CONCLUSION

A CA 125 level should be included as part of the preoperative workup for all patients with uterine cancer. Patients with a preoperative CA 125 level less than or equal to 20 U/mL should be considered as candidates for vaginal hysterectomy unless unfavorable histology or a high-grade (grade II or III) tumor is present. In our series, this approach would have eliminated 24% of the abdominal staging procedures, with a risk of less than 3% for extrauterine disease, while lowering treatment-related morbidity and cutting costs in the treatment of this common female cancer.

Acute effects of 17 beta-estradiol on the coronary microcirculation: observations in sedated, closed-chest domestic swine

OBJECTIVES

To test the hypotheses: that acute administration of 17 beta-estradiol dilates normal coronary microvessels in vivo; that coronary microvascular responses to acute estrogen stimulation exhibit sexual dimorphism; and that nitric oxide has a role in mediating these effects.

METHODS

Measurements of hemodynamics, coronary flow velocity (Doppler), myocardial blood flow (microspheres) and oxygen consumption were made in closed-chest swine: group 1 consisted of castrated juvenile males, groups 2 and 3 of estrogen pretreated, castrated juvenile males, and group 4 of sexually mature females. 17 beta-Estradiol (2, 20 or 200 ng/kg) was given by intracoronary injection and data obtained 20-30 min later; additional measurements were made 1 h after the 200 ng/kg dose. The effect of L-NG-monomethylarginine (L-NMMA) on 17 beta-estradiol responses was also tested. Tissue and blood concentrations of 17 beta-estradiol, and concentrations of estrogen receptor in myocardium and coronary vessels were obtained.

RESULTS

In estrogen-naive castrated males, 17 beta-estradiol had no effect on coronary flow velocity or myocardial blood flow, but 1 h after the 200 ng/kg dose there was an increase in diastolic coronary resistance compared with baseline (48 +/- 20 versus 41 +/- 17 mmHg/mkHz; P < 0.05). Estrogen pretreated castrated males also showed no change in myocardial blood flow after 17 beta-estradiol, but coronary flow velocity decreased (P < 0.05) compared with baseline 1 h after the 200 ng/kg dose (from 1.69 +/- 0.61 to 1.41 +/- 0.42 kHz) and diastolic coronary resistance increased significantly (P < 0.01) compared with control at this time (51 +/- 15 compared with 39 +/- 14 mmHg/mkHz). In sexually mature females, 17 beta-estradiol had no effect on myocardial blood flow but did cause a significant (P < 0.05) decrease in diastolic coronary vascular resistance compared with baseline (51 +/- 9 mmHg/mkHz) at both the 20 ng/kg and the 200 ng/kg doses (both 43 +/- 11 mmHg/mkHz). Coronary flow velocity also increased (P < 0.06) compared with baseline (1.34 +/- 0.26 mmHg/mkHz) after the 200 ng/kg dose (1.69 +/- 0.61 mmHg/mkHz). L-NMMA had no effect on flow responses to 17 beta-estradiol in any group. Classical estrogen receptors were not present in myocardium or coronary arteries from male or female swine.

CONCLUSIONS

These results demonstrate that 17 beta-estradiol exerts a mild constrictor effect on the coronary microvessels of normal castrated, juvenile males whether estrogen-naive or estrogen-pretreated. In contrast, sexually mature normal females exhibit mild dilatation of the coronary microcirculation in response to acute estrogen stimulation. Nitric oxide does not appear to have a role in mediating the dilator response in females, and classical estrogen receptors are not involved. A direct membrane effect of the hormone (perhaps via alteration in potassium conductance) seems likely, and demonstrates sexual dimorphism.

Myocardial adaptation during and after sustained, demand-induced ischemia. Observations in closed-chest, domestic swine

BACKGROUND

We tested the hypotheses that prolonged, demand-induced myocardial ischemia plateaus and that on relief of stress, myocardial function remains depressed, with proportionate reductions in blood flow and oxygen consumption indicative of hibernation.

METHODS AND RESULTS

Closed-chest swine (n = 20) were prepared with an 80% coronary stenosis. Hemodynamics, myocardial blood flow, oxygen, and lactate metabolism were measured in group 1 (n = 9) (1) at baseline, (2) at 10 and 30 minutes of atrial pacing plus intravenous norepinephrine infusion, and (3) in 5 of 9 (group 1a) at approximately 50 minutes after stress. Group 1a had ischemia assessed with 99mTc-labeled BMS 181321. In group 2 (n = 11), myocardial function was determined with radionuclide ventriculography (n = 8), and myocardial necrosis was looked for with trichlorotetrazolium chloride staining (n = 7), histology (n = 10), and myocardial creatine kinase concentration (n = 4). Baseline stenotic-zone endocardial blood flow was reduced versus the normal zone (0.94 +/- 0.33 versus 1.38 +/- 0.27 mL.min-1.g-1, mean +/- SD; P < .05), whereas epicardial flows were comparable (1.15 +/- 0.36 versus 1.16 +/- 0.26 mL.min-1.g-1). Stenotic-zone endocardial flow was unchanged versus baseline at 10 and 30 minutes of stress, whereas epicardial flow increased (1.62 +/- 0.53 mL.min-1.g-1 at 10 minutes and 1.44 +/- 0.51 mL.min-1.g-1 at 30 minutes, both P < .05). Myocardial oxygen consumption increased versus baseline (10.8 +/- 2.9 mL.min-1.100 g-1) at 10 and 30 minutes of stress (14.9 +/- 5.2 and 13.9 +/- 4.5 mL.min-1.100 g-1, both P < .05). After stress, stenotic-zone blood flow and oxygen consumption were reduced approximately 30% (P < .01) versus baseline. In group 2, stenotic-zone contraction with stress declined versus baseline and remained depressed throughout recovery. Histological and biochemical evidence of myocardial necrosis was absent in group 2.

CONCLUSIONS

Myocardial ischemia induced by a sustained increase in oxygen demand may not progress to necrosis but may instead plateau. After relief of stress, myocardial function remains depressed, with a proportionate reduction in blood flow and oxygen consumption consistent with myocardial hibernation.

Acute myocardial infarction complicating viper bite

An acute myocardial infarction was induced by Vipera palaestinea venom in a young patient. The diagnosis was confirmed by cardiac catheterization, which showed a segmental contraction abnormality but normal coronary arteries.

Retrospective review of gynecologic oncology patients with therapy-induced neutropenic fever

We reviewed the course and outcome of gynecologic oncology patients with neutropenic fever (NF), and identified low-risk patients who might be candidates for outpatient management. Charts from patients with the discharge diagnosis of NF from 1990 to 1994 were reviewed for variables related to the febrile neutropenic episode. Outcome was evaluated in terms of the duration of neutropenia, length of hospital stay, NF treatment result, incidence of positive blood cultures, dose reduction in the subsequent course of chemotherapy, and death. Statistical associations between variables and outcome parameters were examined by the Student t test and chi 2 or Fisher's exact tests as indicated. Multivariate analysis by logistic regression was done to determine independent significance of variables. Forty-five episodes of NF were identified involving 40 patients. The median duration of neutropenia following the diagnosis of NF was 2.5 days. The source of fever was unexplained by exam or cultures in 25/45 (56%) episodes. There were two (4%) deaths. In 16/45 episodes, patients had been treated with at least one prior regimen of chemotherapy (median, eight courses). Episodes of NF in patients receiving second-line chemotherapy were associated with a prolonged time of neutropenia (> 3 days, P = 0.058); however, this did not translate into increased hospital stay, treatment failure, or death. Thirteen of 45 (29%) NF episodes developed in patients while already hospitalized for medical or surgical conditions. In this group, cultures were positive in 64% of cases. The remaining 32 NF episodes developed in patients while at home. Patients who developed outpatient NF (ONF) had positive cultures in 23% of cases (P = 0.08) and had a median hospital stay of 4 days. No patient with ONF who remained hemodynamically stable during the first 12 hr of admission suffered serious morbidity. In a multivariate analysis, only bacteremia approached statistical significance in predicting a longer hospital stay (P = 0.07), and no variable studied was predictive of prolonged NF in the ONF group. Our retrospective analysis indicates that patients with ONF who remain stable during the initial 12 hr of hospitalization might safely be discharged home with appropriate antibiotics. Prospective study of outpatient management of NF is required to confirm these findings.

Amifostine pretreatment for protection against cyclophosphamide-induced and cisplatin-induced toxicities: results of a randomized control trial in patients with advanced ovarian cancer

PURPOSE

Serious cumulative toxicity is a well-recognized consequence of chemotherapy. Amifostine, an organic thiophosphate, has demonstrated the ability to protect selectively a broad range of normal, but not neoplastic, tissues from the cytotoxic effects of chemotherapy and radiotherapy. This study was designed to determine if amifostine could reduce the serious toxicities associated with cyclophosphamide and cisplatin (CP), without reducing antitumor efficacy in patients with ovarian cancer.

PATIENTS AND METHODS

Two hundred forty-two patients with advanced ovarian cancer were randomized to receive six cycles of cyclophosphamide (1,000 mg/m2) and cisplatin (100 mg/m2) with or without amifostine (910 mg/m2) every 3 weeks for six cycles. The occurrence of hematologic, renal, neurologic, and ototoxicity was evaluated. Antitumor efficacy was assessed by pathologic tumor response and survival.

RESULTS

Pretreatment with amifostine before each cycle of chemotherapy resulted in a reduction of cumulative toxicities. Hematologic toxicity consisted of grade 4 neutropenia associated with fever and/or infection that required antibiotic therapy (P = .005), days in hospital (P = .019), and days on antibiotics (P = .031). Platinum-specific toxicities consisted of protracted serum creatinine elevations (P = 0.004), > or = 40% reduction from baseline in creatinine clearance (P = .001), and severity of neurologic toxicity (P = .029). Twenty-four percent of CP patients compared with 9% of amifostine plus CP patients discontinued therapy because of protocol-specified toxicity (P = .002). Pathologic tumor response rates were 37% with amifostine and 28% in controls, with comparable median survival times of 31 months. Amifostine was generally well tolerated; the principal side effects were emesis and a transient decrease in blood pressure.

CONCLUSION

Pretreatment with amifostine reduces the cumulative hematologic, renal, and neurologic toxicities associated with the CP regimen, with no reduction in antitumor efficacy.

Phase II trial of hydroxyurea, dacarbazine (DTIC), and etoposide (VP-16) in mixed mesodermal tumors of the uterus: a Gynecologic Oncology Group study

OBJECTIVE

The purpose of this study was to evaluate the efficacy of this three-drug regimen--hydroxyurea, dacarbazine (DTIC), and etoposide (VP-16)--in patients with advanced or recurrent mixed mesodermal tumors (MMT) of the uterus who had not undergone previous chemotherapy. The study was performed as a groupwide phase II study of the Gynecologic Oncology Group.

STUDY DESIGN

Thirty-three evaluable patients received hydroxyurea 2 g in divided doses on Day 1, 700 mg/m2 DTIC and 100 mg/m2 VP-16 on Day 2, and VP-16 100 mg/m2 on Days 3 and 4. Thirty-two patients were evaluable for response. Twenty-six patients had previously undergone abdominal hysterectomy and 11 had received prior radiation therapy, for whom one dose level reduction of the first course was required.

RESULTS

Two patients exhibited complete response and three patients showed partial responses for an overall response rate of 15.7% (95% confidence interval: 5.3-32.8%). Seventeen of 32 patients had stable disease on therapy. Toxicity was acceptable and there were no treatment-related deaths.

CONCLUSION

This regimen reveals moderate activity in patients with advanced or recurrent MMT.

Combination chemotherapy with hydroxyurea, dacarbazine (DTIC), and etoposide in the treatment of uterine leiomyosarcoma: a Gynecologic Oncology Group study

Advanced or recurrent uterine leiomyosarcomas have traditionally been resistant to most chemotherapeutic regimens. Preliminary reports suggested the combination of hydroxyurea, dacarbazine (DTIC), and etoposide (VP-16) was sufficiently effective to warrant larger trials. In a Phase II trial undertaken by the Gynecologic Oncology Group, 39 patients with advanced or recurrent leiomyosarcoma were treated with 2 g of hydroxyurea, 700 mg/m2 of DTIC, and 300 mg/m2 of VP-16 in divided doses every 4 weeks. Thirty-eight patients were evaluable for response. Two patients experienced complete responses and five had partial responses for a total objective response rate of 18.4% (95% confidence interval: 7.7-34.3%). In general, therapy was well tolerated with moderate toxicity. Six of the seven responders had disease outside the pelvis. The combination of hydroxyurea, DTIC, and VP-16 exhibits moderate activity against uterine leiomyosarcoma.

Tissue-type plasminogen activator-induced invasion and metastasis of murine melanomas

The role of tissue-type plasminogen activator (tPA) in the 'spontaneous' as well as 'experimental' metastasis of ocular melanomas in mice was evaluated by transfecting the D5.1G4 murine melanoma cell line that possesses low metastatic activity and low tPA activity with a full length cDNA encoding human tPA. For comparison, a highly metastatic melanoma cell line (Queen's) that constitutively expresses high tPA production, was transfected with a cDNA coding for human plasminogen activator inhibitor type 1 (PAI-1). Unlike non-transfected controls, transfected D5.1G4 melanoma cells expressed high levels of tPA and produced extensive pulmonary metastases following intravenous injection. By contrast, PAI-1 transfected Queen's melanoma cells expressed low tPA activity and displayed significantly reduced metastatic potential compared with nontransfected controls. Moreover, PAI-1 transfected Queen's melanoma cells did not metastasize from the eye while nontransfected parental cells produced extensive spontaneous metastases. Expression of tPA activity in transfected and nontransfected cell lines was completely blocked by an anti-tPA antibody. This antibody significantly inhibited the organ localization and frequency of lung metastases of both Queen's and tPA-transfected D5.1G4 melanomas. This study demonstrates that tPA is involved in the metastasis of murine intraocular melanomas.

What is a normal CA125 level?

CA125 is a coelomic epithelial antigen which is widely used to monitor residual disease in patients undergoing chemotherapy for ovarian cancer. Interpretation of serum CA125 levels has been based on a normal value of 35 U/ml which was derived by screening a young, general population of blood donors which included women with intact reproductive systems. This study addresses the issue of what constitutes a normal serum CA125 level following successful surgical therapy for gynecologic malignancy. Three hundred ninety-three CA125 values were measured in 145 patients after an elapsed time of at least 1 year following completion of surgical therapy for early-stage endometrial or cervical adenocarcinoma. All patients were without evidence of recurrent disease. The mean duration of followup was 4.3 years with a median of 3.7 years. Sixty-seven percent of the CA125 values were less than 10 U/ml; 95% were less than or equal to 20 U/ml. The median value for this patient population was 7.5 U/ml with a mode of 7.1 U/ml. There was no correlation between patient age and CA125 levels. These data suggest that the normal value for CA125 used for patient follow-up after treatment for gynecologic adenocarcinoma needs to be redefined. Our data support an upper limit of normal of 20 U/ml and encourage further study on the clinical impact of this new definition.

The effect of diameter of largest residual disease on survival after primary cytoreductive surgery in patients with suboptimal residual epithelial ovarian carcinoma

OBJECTIVE

The Gynecologic Oncology Group has divided patients with advanced epithelial ovarian cancer into those with optimal residual cancer, in which the maximum diameter of residual is < or = 1 cm, and suboptimal residual cancer, in which the residual disease is > 1 cm. Within the optimal group of patients there is a survival difference between patients with microscopic residual disease and those with any macroscopic disease < or = 1 cm. No analysis of the effect of various residual disease diameters in patients with residual disease > or = 1 cm has been performed. This study evaluates the effect of residual disease diameter in patients with suboptimal disease entered on a randomized trial of intense versus standard chemotherapy.

STUDY DESIGN

Gynecologic Oncology Group protocol 97 compared cisplatin 50 mg/m2 and cyclophosphamide 500 mg/m2 for eight courses with the same drugs at 100 mg/m2 and 1000 mg/m2 for four courses, respectively. There was no difference in progression-free interval or survival between the two arms. Of the 458 stage III (with residual disease > 1 cm) and stage IV patients entered in this study, 294 stage III patients comprise the current analysis. Surgical reporting forms, operation reports, and pathology reports were reviewed to determine initial greatest tumor diameter and residual tumor diameter. Patients were grouped by residual diameter. Multivariate analysis considered residual diameter of disease, age, histologic characteristics, performance status, and ascites. An adjusted relative hazard of dying of ovarian cancer was calculated for each residual disease group.

RESULTS

Patients ranged in age from 20 to 80 years, with a median of 60 years. All patients were Gynecologic Oncology Group performance status 0 to 2. Fifty-two percent had grade 3 tumors, and 39% and 9%, respectively, had grade 2 or 1 tumors. All patients had stage III disease. Ninety percent had serous, endometrioid, or mixed epithelial cell type tumors. Multivariate analysis revealed a relative risk of dying as follows: residual disease < 2 cm, relative risk 1.00; 2 to 2.9 cm, relative risk 1.90; 3 to 3.9 cm, relative risk 1.91; 4 to 5.9 cm, relative risk 1.74; 6 to 7.9 cm, relative risk 1.85; 8 to 9.9 cm, relative risk 2.16; > or = 10 cm, relative risk 1.82. The difference in survival between those with < 2 cm residual disease and those with > or = 2 cm residual disease was significant (p < 0.01). There is no significant difference in the risk of dying between groups with residual disease > or = 2 cm.

CONCLUSIONS

Among patients with suboptimal (> 1 cm residual disease) epithelial ovarian cancer, those who have small diameter residual disease (< 2 cm) tend to survive longer than those who have larger residual disease. Among those with larger residual disease, size does not affect prognosis appreciably.

Measurement of the soluble membrane receptors for tumor necrosis factor and lymphotoxin in the sera of patients with gynecologic malignancy

The shed portion of the 55 and 75 kDa membrane receptors for tumor necrosis factor (TNF) and lymphotoxin (LT) have been described in the serum of patients with cancer. This study was designed to determine whether serum levels of the 55 and 75 kDa soluble TNF/LT receptors (sTNFr) had clinical significance in patients with gynecologic malignancies. Serum samples from 79 patients with ovarian, endometrial, or cervical cancer were assayed for CA 125 levels by RIA and the 55 and 75 kDa sTNFr levels by ELISA. Receptor and CA 125 levels were also analyzed with respect to disease status and response to treatment in banked serum samples from 14 patients with epithelial ovarian cancer who had been followed clinically for 1-3 years. Patients resulted were compared to serum samples tested from normal donors. We found that serum levels of both sTNFr's were elevated in the 79 patients with various gynecologic malignancies [55 kDa of 3.07 +/- 3.79 ng/ml (P < 0.02) and 75 kDa of 2.93 +/- 1.27 ng/ml (P < 0.001)] compared to 16 normal controls (55 kDa of 0.65 +/- 0.22 ng/ml and 75 kDa of 1.62 +/- 0.37 ng/ml). Serum levels of 55 and 75 kDa TNF/LT receptors were a more sensitive indicator of active cancer and had greater predictive value for detecting tumor in patients with ovarian cancer than CA 125. The sTNFr's were also more sensitive than CA 125 in detecting persistent or recurrent tumor and measuring response to therapy. These preliminary results suggest that measurement of serum levels of 55 and 75 kDa sTNFr's, even though not tumor specific, may be a uniquely new method for identifying and monitoring patients with gynecologic malignancy.

Effects of cocaine on human aggression

Thirty male undergraduates received either a placebo, low dose (1 mg/kg), or high dose (2 mg/kg) of orally administered cocaine. Subjects were then given the opportunity to administer electric shocks to an increasingly aggressive fictitious opponent during a competitive reaction-time task. Aggression was defined as the intensity of shock the subject was willing to set for his adversary. The results of this study indicate that subjects in the high-dose cocaine condition reacted more aggressively than placebo subjects irrespective of level of provocation.

Failure to enhance the in vivo killing of human ovarian carcinoma by sequential treatment with dequalinium chloride and tumor necrosis factor

Dequalinium chloride (DECA) is a cationic, lipophilic compound with structure similar to the dye rhodamine 123. DECA is selectively accumulated and retained within the mitochondria of carcinoma cells where it acts as a mitochondrial poison by blocking mitochondrial enzymes which can then disrupt cellular energy production, eventually resulting in cell death. In this manner it is similar to the antimitochondrial effects observed with tumor necrosis factor (TNF). We have previously shown that DECA can synergize the in vitro antitumor effects of TNF against a panel of human ovarian cancer cell lines. Those drug studies have been extended to a xenogenic tumor system with a resultant increase in animal survival. Athymic mice were injected intraperitoneally with 2.0 x 10(7) PA-1 human ovarian cancer cells and DECA +/- TNF treatments begun either on Days 3 or 7 postinjection. Peritoneal tumor implantation was not histologically confirmed by Day 3 postinjection but confirmed by Day 7 following tumor cell injection. Single-agent DECA (5 mg/kg; qod) increased animal survival by 37% (P = 0.002) whereas recombinant human TNF (0.5 micrograms/mouse; qod) only increased survival by 13% (P = 0.27) relative to control animals for those animals treated 3 days post-tumor-injection. Sequential DECA/TNF enhanced animal survival by 45% (P = 0.0002) in similarly treated animals. When drug treatment was initiated 7 days following tumor injection, DECA increased survival by 23% (P = 0.04) while TNF had no effect on prolonging animal survival (3% increase; P = 0.79). Combination DECA/TNF increased survival by 23% (P = 0.04). In the UCI-101 ovarian tumor model, single-agent DECA increased survival by 28% (P = 0.04) while TNF treatment stimulated tumor growth (11% decrease in survival; P = 0.006). Combination DECA + TNF resulted in a 41% increase in survival (P = 0.003). No statistical differences were detected between survival rates for single-agent DECA vs DECA + TNF except for the UCI-101 tumor which showed potentiation due to the in vivo stimulatory effects of TNF.

Morphine and human aggression

Twenty-eight male undergraduates received either 45 mg of immediate-release oral morphine tablets or a placebo. Subjects were then given the opportunity to administer electric shocks to an increasingly aggressive bogus opponent during a competitive reaction-time task. Subjects in the morphine condition were more willing to initiate attacks against their opponent than subjects in the placebo condition, and reacted more aggressively at all levels of provocation.

Corneal topography following excimer photorefractive keratectomy for myopia

Corneal topographic analysis was performed on 97 consecutive eyes with at least one month follow-up after excimer laser photorefractive keratectomy for myopia. Centration of the ablated zone was documented in all eyes at the one month postoperative examination with the Topographic Modeling System (Computed Anatomy Inc., NY). Thirty-seven percent of eyes were within 0.25 mm of the pupillary center (PC); 48% of eyes were between 0.25 and 0.50 mm, 13% were between 0.50 and 1.00 mm, and 2% were more than 1.00 mm from the PC. The greatest amount of decentration was 1.50 mm. The mean decentration was 0.36 mm. The surface regularity index (SRI), which is a measure of the optical performance of the cornea, was significantly less at the sixth postoperative month than at the first postoperative month (P = .013). No correlation between the SRI and the amount of decentration was found. Four main patterns of ablation were noted by differential topographic analysis at the one month interval. A central uniform ablation was present in 45% of eyes; "semicircular ablations" were present in 33% of eyes, a "keyhole" ablation pattern in 12%, and a curious "central bump" ablation pattern in 10%. Corneal topographic analysis was a useful tool for documenting and quantitating results following excimer photorefractive surgery.