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Biomedical subjects

J J Stapleton

Publications and source records attributed to J J Stapleton.

7 recordsLinked to original sources
PubMed2002

Management of corn leafhopper (Homoptera: Cicadellidae) and corn stunt disease in sweet corn using reflective mulch.

Plastic reflective mulches significantly reduced populations of corn leafhopper, Dalbulus maidis (DeLong & Wolcott), adults and the incidence of corn stunt disease caused by Spiroplasma kunkelii (CSS) in late planted sweet corn (Zea mays L.). The reflective mulches were more effective than were either foliar or soil applied insecticides in managing both the leafhopper and the pathogen it transmits. Yields of marketable ears were 1.5 to 2 times greater in reflective mulch plots than from fallow plots. This was due to larger ears (individual ear weight and length) rather than an increase in the number of ears. The use of reflective mulches provides an alternative strategy to insecticides in the management of both D. maidis and corn stunt disease. Such a strategy may prove useful to growers in Latin America and to limited resource growers and organic growers in the United States who wish to grow corn without the use of insecticides.

Animals↗
PubMed2001

Conductance switching in single molecules through conformational changes.

We tracked over time the conductance switching of single and bundled phenylene ethynylene oligomers isolated in matrices of alkanethiolate monolayers. The persistence times for isolated and bundled molecules in either the ON or OFF switch state range from seconds to tens of hours. When the surrounding matrix is well ordered, the rate at which the inserted molecules switch is low. Conversely, when the surrounding matrix is poorly ordered, the inserted molecules switch more often. We conclude that the switching is a result of conformational changes in the molecules or bundles, rather than electrostatic effects of charge transfer.

Journal Article↗
PubMed1984

Extramammary Paget's disease of the vulva in a young, black woman. A case report with histogenic confirmation by immunostaining.

Since the initial report, in 1901, by W. Dubreuilh of a vulvar lesion with the same histopathology as the eczematoid lesion found on the nipple and areola described seven years previously by Sir James Paget, fewer than 100 cases of this uncommon vulvar neoplasia have been reported. This disease process, with and without an accompanying adenocarcinoma, is usually found in postmenopausal Caucasian women. A 24-year-old, black woman gave a subjective history of having had a pruritic vulvar lesion for 18 months. Histologically this neoplasm proved to be extensive extramammary Paget's disease of the vulva with an accompanying adenocarcinoma involving the vulva and, unilaterally, the inguinal-femoral, pelvic and aortocaval lymphatics. Immunoperoxidase staining for carcinoembryonic antigen is valuable for differentiating this disease from similar vulvar lesions plus assessing surgical, chemotherapeutic and roentgenologic treatments for local, regional and distant disease.

Adenocarcinoma↗
PubMed1982

The isolated finding of histiocytes in Papanicolaou smears from postmenopausal women.

The effectiveness of uncovering uterine disease by drawing special attention to increased histiocytes on Papanicolaou smears from postmenopausal patients was evaluated during a 22-month period. Of the 95,593 screened, 478 had increased histiocytes. Half the patients did not have specific follow-up during the study period. One-third had repeated Papanicolaou smears, which were usually unremarkable and free of increased histiocytes. Seventy-eight patients had subsequent endometrial sampling, hysterectomy or both; 41 of these samples failed to disclose pathology. Thirty-seven cases did yield abnormal tissue. However, when the clinical records of those patients were analyzed, it appeared that most had postmenopausal bleeding or an abnormal physical finding. Of five cases in which the finding of increased histiocytes apparently led to uncovering significant uterine disease, two had endometrial cells reported on the Papanicolaou smear in question. There remained only three cases in which the isolated presence of increased histiocytes led to the discovery of disease; they included one instance of adenomatous endometrial hyperplasia and two of endometrial polyp. We conclude that the isolated finding of increased histiocytes in the absence of postmenopausal bleeding or endometrial cells in a postmenopausal patient is a poor indicator of uterine disease. Such a finding, on its own, is insufficient justification for recommending a diagnostic tissue biopsy.

Adenocarcinoma↗
PubMed1981

Daily energy expenditure of young boys as related to maximal aerobic power.

Daily energy expenditure, and participation in regular physical activity over one year, were determined in 28 boys (age 12.3 years) by (1) heart rate (fh) recorded on an oxford Medilog tape recorder and used to approximate energy expenditure using individual fh-VO2 relationships established from a standard step test; total daily average energy expenditure, time spent, and energy expended in activity above a defined threshold, training fh = (.6 (fh max - fh rest) + fh rest) and, (2) a questionnaire designed to determine involvement in regular physical activities over the preceeding year. Maximal oxygen uptake (2.47 +/- 0.36 l-min-1) was measured on a treadmill test. A step-wise multiple regression analysis was used to describe the association between maximal aerobic power and the measures of body size (wt. - 43.8 kg, ht. - 152.2 cm), fatness (sum of skinfolds -67.4 mm), daily energy expenditure (11.66 MJ), and participation in regular physical activity. Body mass and fatness made the only significant contributions to the variance (R2 = 0.77). The relationship was VO2 (l.min-1) = 0.47 (body mass- kg) -0.04 (sum of 6 skinfolds) + 0.71. Measures of daily energy expenditure, the time the heart rate was above a training threshold, and the number of regular physical activities, added little to the measured variance (R2 = 0.78) above that accounted for by body mass amd fatness.

Adolescent↗
PubMedDate not supplied

Paramesonephric papillary serous cystadenocarcinoma: a case report with scanning electron microscopy.

A case report of a malignant tumor, presumably paramesonephric in origin, is presented. Although uncommon, malignancies of the cystic structures of the broad ligament have been reported. The embryologic derivations and histologic feature of these tumors--mesonephric, mesothelial and paramesonephric--have been describe extensively, but no primary lesion has been evaluated previously by scanning electron microscopy. A prior laparotomy and biopsy with a diagnosis of a malignant papillary growth, probably paramesonephric, stimulated the examination of fresh tissue by an ETEC Autoscan scanning electron microscope at subsequent definitive, ablative surgery. Although features of cellular dysplasia were noted, there were no specific, unique characteristics of this neoplasm. Since all reported cases have been premenopausal, a hormonal interaction is questioned.

Adnexa Uteri↗