Here we describe the derivation of novel cell lines from spontaneous mammary tumors that arose in mouse mammary tumor virus-polyomavirus (MMTV-PyV) Middle T (MidT) transgenic mice. Clonal cell lines from four mixed cell populations were tested for adenovirus transducibility and sensitivity to p53 tumor suppressor gene therapy mediated by SCH58500, a replication-deficient adenovirus that expresses human p53. The MidT2-1 cell line was selected for further characterization in vitro and in vivo. This cell line carried the PyV MidT antigen, had wild-type p53 DNA, and was sensitive to suppression of proliferation by MMAC/PTEN tumor suppressor gene therapy. MidT2-1 cells gave rise to highly aggressive tumors in syngeneic FVB mice in both the mammary fat pad and the peritoneal cavity. The histopathology of MidT2-1 tumors closely resembled the histopathology of the primary transgenic tumors. Tumor growth in vivo was inhibited by p53 gene therapy or by MMAC gene therapy. In addition, combination therapy with a number of anticancer agents had synergistic or additive efficacy in vitro. In particular, MMAC gene therapy synergized with SCH58500 or paclitaxel. In the i.p. MidT2-1 tumor model p53 gene therapy enhanced the survival benefits of paclitaxel/cisplatin chemotherapy. Combination therapy has become a mainstay in cancer treatment. In this report, we use a novel transgenic mouse tumor cell line to suggest new combinations that might be explored in clinical cancer care. These include gene therapy using the tumor suppressors MMAC and p53, chemotherapy using farnesyl transferase inhibitors, the microtubule stabilizing taxanes, and the DNA synthesis disruptors gemcitabine and cisplatin. The precise biological mechanisms by which these therapies induce their antitumor effects are not fully elucidated. However, the work presented here suggests that many of these therapeutic approaches have synergistic antitumor activity when used in combination.

Adenoviridae↗

PubMed2000

The EGF receptor provides an essential survival signal for SOS-dependent skin tumor development.

The EGF receptor (EGFR) is required for skin development and is implicated in epithelial tumor formation. Transgenic mice expressing a dominant form of Son of Sevenless (SOS-F) in basal keratinocytes develop skin papillomas with 100% penetrance. However, tumor formation is inhibited in a hypomorphic (wa2) and null EGFR background. Similarly, EGFR-deficient fibroblasts are resistant to transformation by SOS-F and rasV12, however, tumorigenicity is restored by expression of the anti-apoptotic bcl-2 gene. The K5-SOS-F papillomas and primary keratinocytesfrom wa2 mice display increased apoptosis, reduced Akt phosphorylation and grafting experiments imply a cell-autonomous requirement for EGFR in keratinocytes. Therefore, EGFR functions as a survival factor in oncogenic transformation and provides a valuable target for therapeutic intervention in a broader range of tumors than anticipated.

Animals↗

PubMed2000

Inositol 1,4,5-trisphosphate receptors are downregulated in mouse oocytes in response to sperm or adenophostin A but not to increases in intracellular Ca(2+) or egg activation.

Fertilization in mammals stimulates a series of Ca(2+) oscillations that continue for 3-4 h. Cell-cycle-dependent changes in the ability to release Ca(2+) are one mechanism that leads to the inhibition of Ca(2+) transients after fertilization. The downregulation of InsP(3)Rs at fertilization may be an additional mechanism for inhibiting Ca(2+) transients. In the present study we examine the mechanism of this InsP(3)R downregulation. We find that neither egg activation nor Ca(2+) transients are necessary or sufficient for the stimulation of InsP(3)R downregulation. First, parthenogenetic activation fails to stimulate downregulation. Second, downregulation persists when fertilization-induced Ca(2+) transients and egg activation are inhibited using BAPTA. Third, downregulation can be induced in immature oocytes that do not undergo egg activation. Other than fertilization, the only stimulus that downregulated InsP(3)Rs was microinjection of the potent InsP(3)R agonist adenophostin A. InsP(3)R downregulation was inhibited by the cysteine protease inhibitor ALLN but MG132 and lactacystin were not effective. Finally, we have injected maturing oocytes with adenophostin A and produced MII eggs depleted of InsP(3)Rs. We show that sperm-induced Ca(2+) signaling is inhibited in such InsP(3)R-depleted eggs. These data show that InsP(3)R binding is sufficient for downregulation and that Ca(2+) signaling at fertilization is mediated via the InsP(3)R.

Adenosine↗

PubMed2000

Accuracy of assessment of pregnancy duration by women seeking early abortions.

BACKGROUND: Advances in medical abortion might allow women seeking early abortions to terminate their pregnancies safely and effectively without medical supervision. We investigated whether such women can calculate pregnancy duration accurately, a key step in unsupervised use. METHODS: 422 women seeking first-trimester abortions in two clinics (Pune, India, and Atlanta, USA) used a simple worksheet and calendar to calculate the duration of gestation from the date of last menstrual period (LMP) and/or of unprotected intercourse. Clinicians then used standard clinic practices to estimate pregnancy duration. We compared the two sets of estimates, focusing on women who fell into the "caution zone" (ie, had pregnancy durations >8 weeks according to providers, but < or =8 weeks by their own estimates). FINDINGS: The participants were generally representative of the women seeking abortion at the two clinics. 217 (97.7%) of 222 women in Atlanta and 173 (86.5%) of 200 in Pune could produce an estimate of pregnancy duration. Most (85.4% in Atlanta; 93.6% in Pune) of these estimates were within 2 weeks of those made by providers. For estimates based on LMP, only 10.0% (exact 95% CI 6.2-15.0) of women in Atlanta and 9.8% (5.8-15.3) in Pune fell into the caution zone. For estimates based on a date of intercourse, just 7.7% (4.0-13.1) of women in Atlanta and 3.4% (0-17.8) in Pune fell into the caution zone, although fewer women could use this method. INTERPRETATION: The vast majority of women seeking first-trimester abortion in this study could accurately calculate pregnancy duration within a margin of error clinically inconsequential for safe use of unsupervised medical abortion.

Abortion Applicants↗

PubMed2000

Non-steroidal anti-inflammatory drugs in treatment of postoperative pain after cardiac surgery.

PURPOSE: Non-steroidal anti-inflammatory drugs (NSAIDs) are used as analgesic in postoperative pain to reduce opioid side effects, such as drowsiness and nausea. However, NSAIDs have not been used extensively in cardiac surgical patients due to the fear of untoward effects on gastric, renal, and coagulation parameters. This study will evaluate the efficacy and safety of three NSAIDs for pain control in CABG patients. METHODS: One hundred and twenty patients scheduled for elective CABG surgery were enrolled in randomized, double blind, controlled study. Standardized fast track cardiac anesthesia was used. One dose of drug (75 mg diclofenac, 100 mg ketoprofen, 100 mg indomethacin, or placebo) was given pr one hour before tracheal extubation and a second dose 12 hr later. Pain was treated with morphine iv and acetaminophen po. Visual analogue pain scores were recorded at baseline, 3, 6, 12 and 24 hr after the first dose of drug. RESULTS: There were no differences among the groups in pain scores. Only patients who received diclofenac required less morphine than patients in the control group (P < 0.05). When the total amounts of pain medications were computed to morphine equivalents, only patients in the diclofenac group received less pain medications than the placebo group (P < 0.05). Proportion of patients with postoperative increase of creatinine level (20% and over) did not differ between placebo and drug groups. CONCLUSION: Non-steroidal anti-inflammatory drugs may be used for analgesia management post CABG surgery in selected patients. Diclofenac appears to have the best analgesic effects by reducing the morphine and other analgesic requirement postoperatively.

Aged↗

PubMed2000

A profile of early versus late onset of obesity in postmenopausal women.

Obesity is a serious health problem among women across the life span. Although people can become obese at any age, there is a large proportion of older women who have been obese since childhood. The purpose of this study was to determine whether postmenopausal women with an early versus late onset of obesity manifested differences in body habitus, eating behaviors, and mood. One hundred thirty-five postmenopausal women with obesity responded to self-report questionnaires on weight history, weight loss and maintenance expectancy, eating behaviors, and mood. Women with an early onset of obesity had a significantly higher body mass index (BMI), waist circumference, and highest attained adult body weight than women with a late onset of obesity. They had attempted a significantly larger number of diets and had lost more weight on any single diet. The groups also differed significantly on binge eating and overeating in response to negative affect. There was a tendency for women with an early onset to have more depressive and anxious symptoms. Postmenopausal women with an early onset of obesity differed physiologically and psychologically from those with a late onset. Tailoring dietary and behavioral interventions to profiles of postmenopausal women based on onset of obesity may improve the overall efficacy of weight loss programs.

Affect↗

PubMed2000

The ability to generate normal Ca(2+) transients in response to spermatozoa develops during the final stages of oocyte growth and maturation.

Intracellular Ca(2+) oscillations at fertilization are responsible for triggering egg activation. The aim of this study was to examine the effect of the age of the oocyte donor and in-vitro maturation on the generation of Ca(2+) transients at fertilization. The results show that <10% of in-vivo and in-vitro matured oocytes from 19-day old mice develop to the blastocyst stage in vitro. In contrast, 43% of in-vivo and 25% of in-vitro matured oocytes from 24-day old mice developed to the blastocyst stage. In parallel experiments, intracellular Ca(2+) was monitored at fertilization. Oocytes from 19-day old mice generate significantly fewer transients than oocytes from 24-day old mice. In-vitro maturation significantly decreased the ability of oocytes from 19-day old mice but not 24-day old mice to generate Ca(2+) transients in response to spermatozoa. Furthermore, we investigated the effect of oocyte maturation on Ca(2+) signalling. Immature oocytes generated fewer Ca(2+) oscillations and ceased oscillating earlier than mature oocytes. These studies suggest that the ability to generate Ca(2+) transients in response to spermatozoa increases in the final stages of oocyte development and during oocyte maturation. This may contribute to the acquisition of developmental competence in the final stages of oogenesis.

Aging↗

PubMed2000

Epigenetic modifications necessary for normal development are established during oocyte growth in mice.

The ability of maternal chromatin to support full-term development is attained during oocyte growth. The aim of this study was to identify when during the growth phase the maternal chromatin developed the capacity to support term development. Mature metaphase II-arrested oocytes that contained chromatin from oocytes at different stages of oocyte growth were constructed by micromanipulation. The oocytes were fertilized in vitro, developed to the blastocyst stage in vitro, and transferred to recipients to assay developmental potential. The results demonstrate, firstly, that the origin of the maternal chromatin has no effect on the rate of oocyte maturation, fertilization, or development to the blastocyst in vitro. Secondly we demonstrate that maternal chromatin is first competent to support development to term during the latter half of oocyte growth when oocytes are 60-69 microm in diameter in juvenile mice or 50-59 microm in diameter in adult mice. These data show that epigenetic modifications necessary for postimplantation development occur during a specific phase of oocyte growth.

Animals↗

PubMed2000

Mediastinal hematoma following orthotopic heart transplantation.

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Cardiomyopathy, Dilated↗