Improving the representation of stream water sources in surrogate nutrient models with water isotope data.

An important part of meeting nutrient reduction goals in the lower Great Lakes basin and assessing the success of different land management strategies is modeling nutrient losses from agricultural land. This study aimed to improve the representation of water source contributions to streamflow in generalized additive models for predicting nutrient fluxes from three headwater agricultural streams in southern Ontario monitored during the Multi-Watershed Nutrient Study (MWNS). The previous development of these models represented baseflow contributions to streamflow using the baseflow proportion derived using an uncalibrated recursive digital filter. Recursive digital filters are commonly used to partition stream discharge into separate components from slower and faster pathways. In this study, we calibrated the recursive digital filter using stream water source information from stable isotopes of oxygen in water. Across sites, optimization of the filter parameters reduced bias in baseflow estimates by as much as 68 %. In most cases, calibrating the filter also improved agreement between filter-derived baseflow and baseflow calculated from isotope and streamflow data: the average Kling-Gupta Efficiencies using default and calibrated parameters were 0.44 and 0.82, respectively. When incorporated into the generalized additive models, the revised baseflow proportion predictor was more often statistically significant, improved model parsimony, and reduced prediction uncertainty. Moreover, this information allowed for a more rigorous interpretation of how different stream water sources influence nutrient losses from the agricultural MWNS watersheds.

Bilateral metastatic inflammatory carcinoma in the breast from primary ovarian cancer.

A case of ovarian carcinoma with bilateral metastases to the breasts is presented. This is the first report of simultaneous involvement of both breasts presenting as an inflammatory tumor. Axillary lymph node enlargement preceded breast involvement. The related literature is reviewed briefly, and the unpredictable invasiveness of malignant neoplasms is emphasized.

Retroperitoneal, mesenteric, and omental cysts.

Retroperitoneal, mesenteric, and omental cysts are rare abdominal tumors occurring in approximately one of 105,000 hospitalized patients. These cysts have a similar pathogenesis that primarily may be ectopic lymphatic tissue. Retroperitoneal and mesenteric cysts can occur anywhere in the area between the duodenum and rectum but are most common in the small-bowel mesentery, especially the ileum. They can appear as chronic abdominal pain, a painless abdominal mass, or acute abdomen. The most common physical finding of a retroperitoneal or mesenteric cyst is a compressible abdominal mass, movable transversely but not longitudinally; omental cysts are freely movable. Diagnostic aids include abdominal computed tomography and ultrasound. The upper gastro-intestinal (GI) tract series, barium enema examination, and intravenous pyelogram exclude GI and genitourinary cysts and tumors. Treatment of choice is enucleation; resection of the adjacent bowel may occasionally be necessary. Morbidity and mortality should be very low because of modern surgical techniques and follow-up procedures.

Neonatal iron status is impaired by maternal obesity and excessive weight gain during pregnancy.

OBJECTIVE: Maternal iron needs increase sixfold during pregnancy, but obesity interferes with iron absorption. We hypothesized that maternal obesity impairs fetal iron status. STUDY DESIGN: Three hundred and sixteen newborns with risk factors for infantile iron deficiency anemia (IDA) were studied to examine obesity during pregnancy and neonatal iron status. Erythrocyte iron was assessed by cord blood hemoglobin (Hb), zinc protoporphyrin/heme (ZnPP/H) and reticulocyte-ZnPP/H, and storage iron by serum ferritin. RESULT: Women with body mass index (BMI) ⩾ 30 kg m(-)(2), as compared with non-obese women, delivered larger offspring with higher reticulocyte-ZnPP/H and lower serum ferritin concentrations (P<0.05 for both). With increasing BMI, the estimated body iron was relatively lower (mg kg(-)(1)) and the ratio of total Hb-bound iron (mg) per total body iron (mg) increased. Maternal diabetes compromised infant iron status, but multivariate analysis demonstrated that obesity was an independent predictor. CONCLUSION: Obesity during pregnancy and excessive weight gain are independent risk factors for iron deficiency in the newborn.

Malignant fibrous histiocytoma (MFH) arising within a cholecystectomy incision: a cause-and-effect relationship is possible between previous surgery and the development of a malignant fibrous histiocytoma within the operative site.

We present a report of a patient who, after an uneventful cholecystectomy, developed an incisional mass that proved to be a malignant fibrous histiocytoma and had to be excised. Five months later, the patient developed a similar incisional mass, which was shown to be a malignant fibrous histiocytoma and again had to be excised. The rarity of such a case and the details of the patient's case history are reported. The implications of a possible relationship between previous surgery, the patient's healing response, and the development of these tumors are discussed.

Whole-abdomen radiation therapy in ovarian carcinoma: its role as a salvage therapeutic modality.

A significant proportion of patients with epithelial ovarian carcinoma eventually fail after initial responses to chemotherapy. Further treatment with chemotherapy consisting of either the same combination or second-line regimens has been ineffective in producing durable responses. Thus, between June 1983 and June 1987, thirty patients with epithelial ovarian carcinoma who failed one or more chemotherapeutic regimens were treated with whole-abdominopelvic-cavity radiation therapy. Prior to the radiation the amount of residual disease after debulking was noted to be microscopic in 16 patients and macroscopic in 14 patients. Radiation was delivered with an open-field technique that extended from the domes of the diaphragm to the obturator foramina. Doses of 2500 cGy were planned to the whole abdomen, with a boost of another 2500 cGy to the pelvic and or paraaortic nodes when indicated. Higher doses were delivered to the areas of gross disease in the pelvis. Only 2 patients were unable to complete the planned therapy. Another 26% of the patients required interruption of the therapy secondary to hematologic toxicity but eventually completed the treatment. With an overall median follow-up of 14 months, 56% of the patients remain alive. Two-year actuarial survival and recurrence-free survival rates are 47 and 32%, respectively. The survival and recurrence-free survival rates for the group with microscopic residual disease--61 and 33%, respectively--are better than those for the patients with macroscopic residual disease--36 and 18%. The abdominopelvic cavity was the first site of failure in all but one of the 17 patients who have failed. In spite of the higher doses, pelvic failure alone or as a component occurred in 54% of the patients. Small bowel obstruction necessitating surgical intervention as a complication of therapy was seen in 13% of the patients.