Biomedical subjects

D Ripley

Publications and source records attributed to D Ripley.

At least 19 recordsLinked to original sources

PubMed2003

Induction of mosquitocidal activity in mice immunized with Anopheles gambiae midgut cDNA.

Vaccines that induce mosquito-killing (mosquitocidal) activity could substantially reduce the transmission of certain mosquito-borne diseases, especially vaccines against African malaria vectors, such as the mosquito Anopheles gambiae. To generate and characterize antimosquito immunity we immunized groups of mice with two individual A. gambiae midgut cDNAs, Ag-Aper1 (a secreted peritrophic matrix protein) and AgMuc1 (a midgut-bound mucin), and an A. gambiae midgut cDNA library from blood-fed mosquitoes. We observed significantly increased mortality among mosquitoes that fed on either the AgMuc1- or the cDNA library-immunized mice compared to that of controls, but no differences were observed among those fed on Ag-Aper1-immunized mice. Analysis of the humoral and cellular immune responses from mice showed that the induced mosquitocidal effect was associated with immune profiles characterized by elevated tumor necrosis factor alpha and gamma interferon cytokine levels and very low antibody titers. Furthermore, an additional immunization of cDNA library-immunized mice with midgut protein shifted immunity toward a Th2-type immune response, characterized by elevated antibody titers and high interleukin-5 and interleukin-10 cytokine levels; importantly, mosquitoes feeding on these mice exhibited no undue mortality. Finally, when immune sera was ingested by mosquitoes through a membrane feeder, no effect on mosquito mortality was observed, indicating that serum factors alone were not responsible for the mosquitocidal effect. Our results demonstrate that mosquitocidal immunity in mice can be consistently generated by midgut cDNA immunization and suggest this cDNA-induced mosquitocidal immunity is cell mediated.

Animals↗

PubMed2001

The expression and action of granulocyte macrophage-colony stimulating factor and its interaction with TGF-beta in endometrial carcinoma.

OBJECTIVE: Previous studies have demonstrated that normal human endometrium expresses granulocyte macrophage-colony stimulating factor (GM-CSF) and GM-CSF receptors. Because GM-CSF is administer to cancer patients following chemotherapy, GM-CSF may directly or through interaction with ovarian steroids and other cytokines alter the behavior of endometrial cancer. The aim of this study was to determine the expression of GM-CSF and receptors in endometrial carcinoma and its direct effect and interaction with transforming growth factor beta (TGF-beta) on Ishikawa cells, a human endometrial carcinoma cell line. METHODS: GM-CSF, GM-CSF receptors, TGF-beta1, and TGF-beta type II receptor expression were evaluated using quantitative reverse transcription polymerase chain reaction (Q-RT-PCR). The effect of GM-CSF on DNA synthesis, cell proliferation, expression of GM-CSF, TGF-beta1, and TGF-beta receptor, and their regulation by ovarian steroids was determined by the rate of [(3)H]thymidine incorporation, MTT assay, Q-RT-PCR, and ELISA, respectively. RESULTS: Endometrial carcinomas express significantly higher GM-CSF and GM-CSF alpha and beta receptor mRNA compared with normal postmenopausal endometrium. GM-CSF at various doses had no significant effect on the rate of [(3)H]thymidine incorporation or proliferation of Ishikawa cells, whereas TGF-beta1 inhibited [(3)H]thymidine incorporation. GM-CSF and TGF-beta1 regulate their own expression and the expression of TGF-beta type II receptor, which were both upregulated by 17beta-estradiol and medroxyprogesterone acetate treatment and reversed following cotreatment with their respective receptor antagonists. CONCLUSION: Endometrial carcinoma expresses an elevated level of GM-CSF and GM-CSF receptors. GM-CSF is not a mitogen for the endometrial cancer cell line; however, either alone or through interaction with TGF-beta1, it regulates its own expression and the expression of TGF-beta1 and TGF-beta type II receptor which inhabits endometrial cancer cells. This interaction may represent a regulatory feedback mechanism that could serve to suppress endometrial carcinoma growth.

Antineoplastic Agents, Hormonal↗

PubMed2001

Aggressive uterine sarcoma with rhabdoid features: diagnosis by peritoneal fluid cytology and absence of INI1 gene mutation.

We report a primary uterine sarcoma with classic histologic, immunohistochemical, and ultrastructural features of a malignant extrarenal rhabdoid tumor (MERT). It arose in a 71-year-old woman who presented with postmenopausal bleeding, ascites, and a right pelvic mass. Malignant cells with rhabdoid morphology were identified by cytologic examination of the peritoneal fluid. Exploratory laparotomy revealed a 10-cm right adnexal mass and disseminated peritoneal tumor. Pathologic study showed diffuse expansion of the endometrial stroma by rhabdoid-like cells with transmural infiltration of the myometrium and extensive involvement of uterine serosa and right ovary by tumor. Neoplastic cells were immunoreactive for vimentin, cytokeratin, and epithelial membrane antigen, and cytoplasmic whorls of intermediate filaments were observed by electron microscopy. Fluorescence in situ hybridization (FISH) studies with chromosome 22-specific probes showed no loss of the INI1 gene, and no coding sequence mutation was identified.

Aged↗

PubMed2001

Charges and lengths of stay for acute and inpatient rehabilitation treatment of traumatic brain injury 1990-1996.

This investigation evaluated yearly trends in charges and lengths of stay for patients with brain injury in acute care and rehabilitation settings over a 7 year period. Data was collected from 800 consecutive patients enrolled in four NIDRR Model Systems Traumatic Brain Injury programmes. Acute care daily charges showed almost routine increases, averaging nearly $550 per year. Conversely, lengths of stay generally showed a downward trend, with annual reductions averaging 2.25 days. Admission lengths of stay averaged 22-29 days between 1990-1994. Admissions averaged less than 20 days beginning in 1995, with the 1996 average of 16 days, nearly half that of the 1993 average. Between 1990-1996, average daily rehabilitation charges increased each year, with the rise averaging $83 or 7%. The rise in daily rehabilitation charges was offset by corresponding decreases in lengths of stay averaging 3.65 days or 8% annually. Increases in daily charges for brain injury rehabilitation care were roughly comparable to those for general medical care prices. However, the rate of change in acute care charges was substantially greater, with annual increases averaging 10% more than national medical care prices. The steady downward trend in lengths of stay raises serious concerns about the future availability of health care services to persons with brain injury.

Adult↗

PubMed1999

The impact of laparoscopic surgery in the management of adnexal masses.

The objective of this study is to evaluate the clinical aspects of laparoscopic management of adnexal masses. The feasibility of this approach has been demonstrated, but the safe and effective use of laparoscopy for this indication requires training, technical skills and experience on the part of the laparoscopist. If used appropriately, many patients will benefit from minimally-invasive surgery. We compared clinical factors of patients having laparoscopy to those having laparotomy in a case-control study of 30 patients with adnexal masses. Oophorectomy or ovarian cystectomy was performed by laparoscopy for 20 women and by laparotomy for 10 women. Comparing the 2 groups, the most significant difference was the decrease in length of hospital stay in the laparoscopy group. There were no significant differences in operative time or intraoperative complications. Estimated blood loss was lower in the laparoscopy group, and no intraoperative complications occurred. No patient required conversion from laparoscopy to laparotomy. All patients had benign disease despite the inclusion of patients with risk factors for ovarian carcinoma. This study clearly demonstrates the clinical benefits of laparoscopic management of adnexal masses treated with oophorectomy or ovarian cystectomy.

Adnexal Diseases↗

PubMed1996

Managed care in gynecologic oncology.

We review the recent literature on managed care and its application to gynecologic oncology. Although the literature is limited, we discuss professional agreement contracts, the role of primary care physicians and specialists in gynecologic cancer screening, changes in health care distribution, changes in physician-patient relationships, and cancer research.

Contract Services↗

PubMed1995

Adenocarcinoma of the cervix in a renal transplant patient.

Treatment of cervical carcinoma in a renal transplant patient with a single pelvic kidney presents several management dilemmas. Standard treatment modalities are complicated by the patient's immunosuppressed state and the location of the transplanted kidney in the standard pelvic field, as well as other surgical risks. No information on the best approach to this clinical situation is available in the English language literature. We present this case to discuss factors considered in selecting a treatment plan and possible reasons for the rapid recurrence and demise of this patient.

Adenocarcinoma↗

PubMed1989

Human immunodeficiency virus inhibition is prolonged by 3'-azido-3'-deoxythymidine alternating with 2',3'-dideoxycytidine compared with 3'-azido-3'-deoxythymidine alone.

The inhibition of the lymphadenopathy-associated virus strain of human immunodeficiency virus (HIV) by alternating regimens of two dideoxynucleosides, 3'-azido-3'-deoxythymidine (AZT) (zidovudine) and 2',3'-dideoxycytidine (ddC), was determined in CEM cells. Cultures infected with virus for 2 h were treated with clinically achievable concentrations of AZT, ddC, or a 3-day-alternating regimen of AZT and ddC. Media were completely changed every 3 days and replaced with antiviral agent, and virus production was assayed by p24 antigen and virus-specific DNA. Cells treated with no antiviral agent exhibited breakthrough infection by day 6 in culture, whereas cells treated with 0.1, 1.0, or 3.0 microM AZT had a prolonged time to viral breakthrough. For each regimen of AZT alternating with 0.05 or 0.1 microM ddC, there was consistently prolonged HIV inhibition compared with continuous treatment with AZT alone. The viral suppression achieved with the alternating combinations required AZT as well as ddC and was superior to 3 days of treatment with ddC alternating with 3 days of no antiretroviral treatment. Levels of unintegrated HIV DNA paralleled the detection of p24 antigen, with the most prolonged inhibition of virus-specific DNA occurring with AZT alternating with ddC (compared with all regimens except continuous treatment with ddC). These data suggest that alternating regimens of AZT and ddC not only might decrease toxicity associated with the two drugs but may prove to be more efficacious than AZT alone.

Antiviral Agents↗

PubMed1978

Vitamin B12 assimilation from chicken meat.

Chicken meat labeled in vivo with radio-B12 was ingested by normal volunteers. The absorption, measured by the fecal excretion method, was similar to that reported for crystalline radiocyanocobalamin and for mutton, but exceeded that from eggs. Parenteral injection of 1000 microgram of nonlabeled vitamin B12 did not interfere with the absorption of the radio-B12 from the meat. The urinary radioactivities, which were as low as those after oral administration of radioactive hydroxocobalamin and vitamin B12 coenzyme, suggested that the radio-B12 was present in meat in coenzyme form or was converted into the stable hydroxoform during the process of cooking and digestion. Patients with pernicious anemia showed insignificant urinary radioactivities in a standardized urinary excretion test using chicken meat whereas subjects with simple gastric achlorhydria and partial gastrectomy had subnormal values although their absorption of crystalline radiocyanocobalamin was normal. The subnormal serum vitamin B12 concentration seen in these latter subjects may, therefore, be due to impaired assimilation of vitamin B12 from food.

Achlorhydria↗

PubMed1977

Influence of age and stomach function on serum vitamin B12 concentration.

Serum vitamin B12 (B12), maximal gastric acid output (MAO), and B12 absorption were determined in 82 subjects, age 32 to 85 years, who had normal absorption of radiocyanocobalamin. In 46 of the patients the gastric intrinsic factor (IF) was also measured. Serum B12 concentration and MAO varied widely in all age groups from abnormally low to definitely normal. The mean values for serum B12 and MAO, however, declined very similarly with advancing age owing to an increased incidence of low values for these two measurerment in the aged. There was no significant fall in the mean B12 absorption or IF secretion as a function of old age. Achlorhydric and hypochlorhydric patients invariably had lower mean serum B12 concentrations than those with adequate MAO. Conversely, patients with normal MAO all had normal serum B12 levels. Serum B12 concentration, although correlating with both MAO and IF secretion, showed a closer relationship to the former than to the latter. These findings suggest that the stomach, aside from producing the IF, plays an important role in maintaining a normal serum B12 concentration.

Adult↗

PubMed1976

Inhibitory effect of eggs on vitamin B12 absorption: description of a simple ovalbumin 57Co-vitamin B12 absorption test.

Ovalbumin and egg yolks, mixed separately in vitro with radiocyanocobalamin (57 Co-vitamin B12), were served to normal volunteers in a cooked form. Ovalbumin, and to a lesser degree, egg yolks were observed to inhibit vitamin B12 absorption. This observation explains the rather poor assimilation of vitamin B12 from eggs labelled in vivo with 57 Co-vitamin B12.

Absorption↗

PubMed1975

Vitamin B12 absorption from eggs.

The assimilation of 57Co B12 from in vivo labeled eggs was much inferior to that of a comparable amount of crystalline 57Co B12. Furthermore, the absorption varied with the form in which the eggs were served. Judged by the urinary excretion test and the plasma absorption of radioactivity the average absorption from boiled and fried eggs was more than twice that from scrambled whole eggs, but less than half that absorbed from crystalline 57Co B12.

Cobalt Radioisotopes↗

PubMed1974