PubMed Health⌕ Search

Biomedical subjects

C Hendrickson

Publications and source records attributed to C Hendrickson.

10 recordsLinked to original sources
PubMed1989

Characteristics of flow-mediated brachial artery vasodilation in human subjects.

In an effort to determine whether arterial conductance vessels dilate in response to increased blood flow stimuli, brachial artery area (cm2) and diameter (cm) were derived by simultaneous measurement of forearm blood flow (ml/min.100 ml) and brachial artery blood flow velocity (cm/sec) following the release of arterial occlusion. Measurements were made at rest and at the time of maximal flow after the release of graded periods of forearm arterial occlusion (20 seconds to 10 minutes). These studies showed a graded large vessel dilation following occlusions of up to 1 minute (baseline diameter, 0.33 +/- 0.01; after 1 minute occlusion, 0.45 +/- 0.02 cm; p less than 0.05) after which time diameter plateaued (after 10 minutes of occlusion, 0.48 +/- 0.02 cm). In addition, the time course of diameter and flow changes after 3 minutes of arterial occlusion were examined. Flow was maximal at 5 seconds but diameter was maximal at 15-30 seconds after release. Furthermore, the half time for the return of diameter to baseline was longer than that for blood flow. We also measured the diameter after forearm heating (42 degrees C) and noted a substantial increase in diameter (before heating, 0.32 +/- 0.01; after heating, 0.39 +/- 0.02 cm; p less than 0.05). Finally, we applied pressure to the venous side of arteriovenous fistulae in five hemodialysis patients. This maneuver was associated with large reductions in forearm blood flow (baseline flow, 63.3 +/- 10.6; venous compression flow, 36.0 +/- 4.4 ml/min.100 ml; p less than 0.05) and a decrease in brachial artery size (baseline diameter, 0.63 +/- 0.07; venous compression diameter, 0.58 +/- 0.06 cm; p less than 0.05). We conclude that 1) the human brachial artery size changes in response to changes in blood flow, and 2) the maximal dilation occurs after maximal flow is noted. Although alternate explanations are possible for each of our observations, our results are most consistent with a flow-mediated, localized vasodilating process.

Adult↗
PubMed1987

A Northern California Oncology Group randomized trial of leucovorin plus 5-fluorouracil versus sequential methotrexate, 5-fluorouracil, and leucovorin in patients with advanced colorectal cancer who failed treatment with 5-fluorouracil or 5-fluorodeoxyuridine alone.

The current study was initiated to confirm preliminary reports that 20% or more of patients with colorectal cancer who fail treatment with 5-fluorouracil (FUra) will respond to treatment with either leucovorin plus FUra or with sequential methotrexate, FUra, leucovorin. One hundred two patients with advanced, measureable colorectal cancer who failed treatment with FUra and/or 5-fluorodeoxyuridine (FUdR) were randomized to treatment with either high-dose leucovorin plus FUra (Arm B) or sequential methotrexate, FUra, leucovorin (Arm C). In this interim report, 92 patients were evaluable for toxicity and 89 patients were evaluable for response. Grade 3 or 4 nonhematologic toxicity which was primarily gastrointestinal was experienced by 25% of patients on both treatment arms during at least 1 treatment cycle. Hematologic toxicity was minimal. Among 43 evaluable patients on Arm B, there were 2 complete responses (5%) and 1 minor response (3%). Among 46 evaluable patients on Arm C, there was 1 complete response (2%), 1 partial response (2%), and 6 minor responses (14%). The median time to treatment failure was 2.2 months on Arm B and 3.5 months on Arm C. The median survival was 8.3 months on Arm B and 8.7 months on Arm C. Colorectal cancers that are resistant to FUra are cross-resistant to both experimental combinations.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1983

A randomized phase III study of cisplatin with or without methotrexate for recurrent squamous cell carcinoma of the head and neck. A Northern California Oncology Group study.

Eighty patients with recurrent squamous cell cancer of the head and neck were randomized to cisplatin (80 mg/m2) every 3 weeks or cisplatin plus weekly methotrexate (250 mg/m2) with leucovorin. The overall response rate to cisplatin was 18%, with 10% complete responses. The overall response to the combination was 33% with 18% complete responses (P = 0.11). There was no difference in response duration, time to progression, or survival. There was no difference in renal toxicity between the 2 arms (creatinine greater than 2 mg/dl in 6% of the patients). There was significantly more leukopenia (64%), thrombocytopenia (18%), anemia (18%), and mucositis (33%) in the combination arm. This combination of two of the best agents for head and neck cancer did not improve response, but resulted in added toxicity.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1980

Stabilization of human breast cancer progesterone (5020) receptor by sodium molybdate.

Inclusion of the salt, sodium molybdate, at 20 mmol/l concentration during the determination of progesterone receptor in human breast cancer cytosols was associated in a number of samples with marked stabilization of binding by the radioactive ligand, 5020, to 8S and 4S receptors. Both the percent of positive patients and the absolute amount of PR were increased, with the appearance of 8S peaks where none had been evident in controls without the salt, and increased amounts of 8S and 4S binding in other samples. In addition, results from some dextran-coated charcoal assays were altered, and positive samples incubated in the presence of the salt frequently yielded higher values of PR. Finally, estrogen receptor values determined by SDG assays have been increased in the presence of the salt. Routine addition of sodium molybdate to samples analyzed for PR by centrifugation overnight can be expected to yield an increased percent of receptor-positive patients with higher average concentration of receptor, compared with results of previous methodology. Its presence during the dextran-coated charcoal assay can also alter the measured binding. Although the stability of ER during overnight centrifugation is greater, in some patients additional receptor can be detected when buffers include this salt.

Breast Neoplasms↗
PubMed1980

Sodium molybdate increases the amount of progesterone and estrogen receptor detected in certain human breast cancer cytosols.

When sodium molybdate is added at a final concentration of 20 mM, additional 8S and 4S progesterone (3H-R5020) receptor can be detected in the cytosols from a number of human breast cancers. Additional estrogen receptor also could be measured in some cytosols, and a quantitative temperature-dependent conversion of 8S to 4S binding molecules achieved. Sodium molybdate also prevented the loss of binding activity that occurred when cytosols were incubated at 30 degrees in the absence of added estradiol. In addition to increasing the amount of progesterone receptor, and to a lesser extent estrogen receptor that may be detected, elicidation of the mechanism by which this salt stabilized receptors should contribute to further understanding of how cytosol steroid receptor content and function is regulated.

Breast Neoplasms↗
PubMed1967

A reversed PRE.

Explore the source record for details and available documents.

Animals↗