Silent ovulation in rhesus monkeys (M. mulatta): dissociation of hormonal and behavioral states

Ovarian hormone levels were monitored in rhesus monkeys during the breeding and non-breeding seasons. Ovulation (as inferred from progesterone levels in blood serum in excess of 1.5 ng/ml) was most frequent in the breeding season but was absent only during the month of August. Summer (non-breeding season) ovulations were more frequently "silent," or without heterosexual behavior, than were winter ovulations. This finding suggested that estradiol stimulation may cause different behavioral responses at different times of the year. To test this hypothesis, ovariectomized females were treated with subcutaneously implanted estradiol capsules at different times within and outside the normal breeding season. In either season, treatment with estradiol resulted in increased female-to-female sexual behavior. Only during the breeding season, however, did the estradiol-treated ovariectomized females interact sexually with males. Although males copulated with both estradiol-treated and gonadally intact, untreated females during the breeding season, their rate of copulation with the intact females was higher. The results suggest that: (1) Some female rhesus monkeys displaying strictly seasonal breeding behavior continue to have luteal activity indicative of ovulation in May, June and July, (2) Summer ovulatory cycles are rarely accompanied by sexual behavior, (3) Estradiol treatment of ovariectomized females induces female-to-female sexual behavior both in the breeding and non-breeding seasons, and (4) Males are less responsive to the presence of estrogen-stimulated females in the non-breeding season than in the breeding season.     

Multiple sclerosis. The problem of incorrect diagnosis

Various neurologic disorders may be diagnosed incorrectly as multiple sclerosis (MS) since there is no test that is entirely specific for the disease. We report ten patients who met clinical criteria for probable or definite MS and who were given incorrect diagnoses. All of the patients were subsequently shown to have alternative diagnoses, three of which were directly treatable. From these illustrative cases, five characteristics were identified that alerted us to the possibility of an alternative diagnosis. We have called these characteristics "red flags," and suggest that they may be useful as features casting doubt on the diagnosis of MS if used judiciously in conjunction with clinical diagnostic criteria.     

Growth hormone attenuates tumor necrosis factor alpha in burned children

BACKGROUND: Recombinant human growth hormone (rhGH) has been shown to favorably modulate the acute-phase response and may improve the clinical outcome. OBJECTIVE: To examine whether rhGH attenuates the elevated tumor necrosis factor alpha (TNF-alpha) levels that correlate with increased multiorgan failure and mortality in burned adults and children. DESIGN: Twenty children with burns of greater than 40% of the total body surface area were randomly divided into 2 groups to receive placebo (n = 10) or rhGH, 0.2 mg/kg per day intramuscularly (n = 10). SETTING: Pediatric burn hospital. MAIN OUTCOME MEASURE: Serum TNF-alpha levels by enzyme-linked immunoassay at baseline (day 0) and at 21 and 42 days after injury. For statistical analysis, we used the Kruskal-Wallis and Friedman tests. RESULTS: No significant differences in age (mean +/- SD, 6.2+/-1.6 vs 5.0+/-1.2 years) or percentage of total body surface area burn (mean +/- SD, 65.1%+/-8.2% vs 57.1%+/-5.2%) could be shown between the groups given rhGH and placebo. Baseline TNF-alpha levels were elevated from reference values in both groups. Twenty-one and 42 days after rhGH administration, serum TNF-alpha levels were significantly decreased from those at baseline (P<.05). No significant decrease in TNF-alpha levels was observed in the placebo group (P = .5). CONCLUSIONS: Recombinant human growth hormone significantly lowers serum TNF-alpha levels after burn injury. This is consistent with the beneficial effect that rhGH has on the acute-phase response.     

A biologic risk model for stage I lung cancer: immunohistochemical analysis of 408 patients with the use of ten molecular markers

OBJECTIVE: The standard treatment of patients with stage I non-small cell lung cancer is resection of the primary tumor; however, the recurrence rate is 28% to 45%. This study evaluates a panel of molecular markers in a large population of patients with stage I non-small cell lung cancer to determine the prognostic value of each marker and to create a biologic risk model. METHODS: Pathologic specimens were collected from 408 consecutive patients after complete resection for stage I non-small cell lung cancer at a single institution, with follow-up of at least 5 years. A panel of 10 molecular markers was chosen for immunohistochemical analysis of the primary tumor on the basis of differing oncogenic mechanisms. Local tumor expansion requires growth regulating proteins (epidermal growth factor receptor, the protooncogene erb-b2); apoptosis proteins (p53, bcl-2); and cell cycle regulating proteins (retinoblastoma recessive oncogene, KI-67). Local tumor invasion requires angiogenesis (factor viii). The development of distant metastases involves the expression of adhesion proteins (CD-44, sialyl-Tn, blood group A). Cox proportional hazards regression analysis was used to construct an independent risk model for cancer recurrence and death. RESULTS: Multivariable analysis demonstrated significantly elevated risk for the following molecular markers: p53 (hazard ratio, 1.68; P =.004); factor viii (hazard ratio, 1.47 P =. 033); erb-b2 (hazard ratio, 1.43; P =.044); CD-44 (hazard ratio, 1. 40; P =.050); and retinoblastoma recessive oncogene (hazard ratio, 0. 747; P =.084). CONCLUSIONS: Five molecular markers were associated with the risk of recurrence and death, representing independent metastatic pathways: apoptosis (p53), angiogenesis (factor viii), growth regulation (erb-b2), adhesion (CD-44), and cell cycle regulation (retinoblastoma recessive oncogene). This study demonstrates the validity of this molecular biologic risk model in patients with stage I non- small cell lung cancer.     

Substructure of the inner core of the Earth

The rationale is disclosed for a substructure within the Earth's inner core, consisting of an actinide subcore at the center of the Earth, surrounded by a subshell composed of the products of nuclear fission and radioactive decay. Estimates are made as to possible densities, physical dimensions, and chemical compositions. The feasibility for self-sustaining nuclear fission within the subcore is demonstrated, and implications bearing on the structure and geodynamic activity of the inner core are discussed.     

Effects of tracheostomies on infection and airway complications in pediatric burn patients

Considerable controversy exists as to whether tracheostomy is ever indicated in burn patients. New advents in the treatment of inhalation injury have improved survival, making the use of tracheostomy more usual. The purpose of this study was to analyze the outcome of tracheostomies, and the effect of time on complications. Patients requiring ventilatory support and tracheostomies were studied. Demographic data, hospital course, ventilatory parameters and complications were analyzed. Two hundred ninety patients required ventilation and 36 tracheostomy. Mean percentage of TBSA burned was 59%+/-4. Ninety percent of these patients presented with inhalation injury. Mortality in tracheostomy patients was 25 and 16% in all ventilated patients. Thirty-five percent of the patients developed late complications. Patients who had their airway converted to tracheostomy before day 10 postinjury had a significantly lower incidence of subglottic stenosis. and patients who required airway pressures over 50 cm H2O for more than 10 days had a significantly higher incidence of tracheomalacia. Pneumonia occurred at similar incidence in ventilated and tracheostomy patients. The mortality and late complications of pediatric burn patients with tracheostomy has decreased over the last decade. They do not present with higher incidence of pneumonia. Maintenance of airway pressures below 50 cm H2O and conversion of the artificial airway to tracheostomy before day 10 postinjury may be advisable in patients requiring long term ventilation to prevent late complications.     

Phase II trial of gefitinib in recurrent glioblastoma.

PURPOSE: To evaluate the efficacy and tolerability of gefitinib (ZD1839, Iressa; AstraZeneca, Wilmington, DE), a novel epidermal growth factor receptor tyrosine kinase inhibitor, in patients with recurrent glioblastoma. PATIENTS AND METHODS: This was an open-label, single-center phase II trial. Fifty-seven patients with first recurrence of a glioblastoma who were previously treated with surgical resection, radiation, and usually chemotherapy underwent an open biopsy or resection at evaluation for confirmation of tumor recurrence. Each patient initially received 500 mg of gefitinib orally once daily; dose escalation to 750 mg then 1,000 mg, if a patient received enzyme-inducing antiepileptic drugs or dexamethasone, was allowed within each patient. RESULTS: Although no objective tumor responses were seen among the 53 assessable patients, only 21% of patients (11 of 53 patients) had measurable disease at treatment initiation. Seventeen percent of patients (nine of 53 patients) underwent at least six 4-week cycles, and the 6-month event-free survival (EFS) was 13% (seven of 53 patients). The median EFS time was 8.1 weeks, and the median overall survival (OS) time from treatment initiation was 39.4 weeks. Adverse events were generally mild (grade 1 or 2) and consisted mainly of skin reactions and diarrhea. Drug-related toxicities were more frequent at higher doses. Withdrawal caused by drug-related adverse events occurred in 6% of patients (three of 53 patients). Although the presence of diarrhea positively predicted favorable OS from treatment initiation, epidermal growth factor receptor expression did not correlate with either EFS or OS. CONCLUSION: Gefitinib is well tolerated and has activity in patients with recurrent glioblastoma. Further study of this agent at higher doses is warranted.     

Combined modality trials of the Cancer and Leukemia Group B in stage III non-small-cell lung cancer: analysis of factors influencing survival and toxicity.

BACKGROUND: Combined modality therapy (CMT) is the standard of care for patients with unresectable stage III non-small-cell lung cancer (NSCLC); however, insufficient data are available regarding prognostic factors in this disease setting. PATIENTS AND METHODS: Six hundred and ninety-four patients included in five trials conducted by the Cancer and Leukemia Group B evaluating CMT in stage III NSCLC were included in this analysis. The primary objective was to identify factors that were predictors of survival and selected radiation-related toxicities using Cox regression models and logistic regression analysis. RESULTS: The Cox model shows that performance status (PS) 1 [hazard ratio (HR) 1.24; 95% confidence interval (CI) 1.06-1.45; P=0.009] and thoracic radiation therapy (TRT) only (HR 1.58; 95% CI 1.22-2.05; P=0.001) predicted for poorer survival, while baseline hemoglobin >/=12 g/dl predicted for improved survival (HR 0.67; 95% CI 0.55-0.81; P 5% weight loss (OR 2.9; 95% CI 1.3-6.6; P=0.008) and patients receiving concurrent chemoradiation (OR 7.3; 95% CI 3.4-15.6; P=0.0001). CONCLUSIONS: Baseline hemoglobin and PS, as well as the use of CMT, have the greatest effect on survival in unresectable stage III NSCLC. The use of concurrent chemoradiation increases the risk of esophagitis, which remains the primary radiation-related toxicity.