Increase in the calculated resistance of anatomically fixed stenosis in vitro in association with decrease in distal resistance.

The effects of changes in distal resistance on stenotic resistance were studied in vitro. Physiological saline was passed through the left carotid artery obtained from the dog, flexible rubber tubing, or through solid polyethylene tubing with a constant perfusion pressure or with a constant flow rate. Various stenotic resistances were established using a screw type constrictor and the distal resistance was varied by allowing physiological saline to pass through either a 23 gauge hypodermic needle (high peripheral resistance) or 23 and 20 gauge needles (low peripheral resistance ). For arteries with anatomically fixed stenosis, the calculated resistance was increased in association with reduction of the distal resistance. The stenotic resistance in the flexible rubber tubing changed in the same manner as that of the carotid artery, while the solid polyethylene tubing showed no significant stenotic resistance changes due to altering the distal resistance. These findings suggest that the stenotic resistance change of the artery correlates with the elasticity of the vessel wall and also indicate that resistance values were of little usefulness for evaluating the effects of vasodilating stimuli on the vessel segment with a significant stenosis.</p

Associations among baseline variables, treatment-related factors and health-related quality of life 2 years after breast cancer surgery

Provision of social support and rehabilitation for patients with physical, mental, and functional problems after cancer treatment is important for long-term health-related quality of life (HRQOL). Effective use of human and financial healthcare resources requires identification of patients requiring rehabilitation. The objectives of the current study were to clarify the patterns of physical and psychosocial recovery over time, to evaluate the associations among baseline variables, treatment-related factors and HRQOL at 6 months, 1, and 2 years after breast cancer surgery, and to identify the significant factors predicting HRQOL at each point. A multicenter longitudinal study was performed to evaluate physical conditions, anxiety, depression, and HRQOL at 1 month (baseline), 6 months, 1, and 2 years after surgery in 196 patients (mean age: 53.3 years old) with early breast cancer and no postoperative recurrence. Physical conditions were evaluated using a patient-reported symptom checklist. HRQOL was rated using the functional assessment of cancer treatment scalegeneral (FACT-G) and the breast cancer subscale (FACTB). Anxiety and depression were rated using the hospital anxiety and depression scale (HADS). More than 50% of patients had local problems of "tightness", "arm weakness." and "arm lymphedema", and systemic problems of "reduced energy, fatigue, and general weakness" postoperatively. The HRQOL score significantly improved 1 year after surgery, and scores for physical, emotional and functional well-being also increased with time, whereas the score for social well-being was the highest at baseline and decreased with time. Depression and anxiety significantly improved with time. Concomitant disease, marital status, and the presence of a partner, anxiety and depression at baseline, pathological lymph node involvement, and adjuvant intravenous chemotherapy were significant factors predicting FACT-G scores at 6 months, 1, and 2 years after surgery. Depression at baseline was a strong predictor of HRQOL up to 2 years after surgery. These results suggest that physical rehabilitation is required for tightness and lymphedema to improve long-term postoperative physical function. A further study of psychosocial interventions is required to improve depression and social well-being after breast cancer surgery

Factors influencing acute high-grade restenosis in emergency percutaneous transluminal coronary angioplasty for acute myocardial infarction.

We studied the factors which may induce acute high grade restenosis in emergency percutaneous transluminal coronary angioplasty (PTCA). PTCA was attempted in 50 patients with acute myocardial infarction, and the balloon catheter passed successfully across the occlusion site in 47 (94%) of the patients. These 47 patients were analyzed. &#34;Acute restenosis&#34; was defined as a lesion which was revascularized to less than 50% luminal reduction narrowed again to more than 75% luminal reduction 5 min after the balloon inflation. Univariate and multivariate analyses were used for determining factors which significantly influenced acute restenosis. The incidence of at least one restenosis episode was 45%. Multiple regression analysis selected 5 factors associated significantly with an increased rate of acute restenosis: 1) angiographic evidence of dissection, 2) lesion in the right coronary artery (RCA), 3) lack of or insufficient administration of thrombolytic agent preceding PTCA, 4) curved lesion and 5) relatively small balloon/artery diameter ratio. Acute restenosis correlated significantly with late reocclusion. This study indicates that it is important to administer a thrombolytic agent prior to emergency PTCA, and to use an adequately sized balloon to the artery when the acute restenosis occurs by using relatively smaller sized balloon. The present data also demonstrated that patients with RCA and a curved lesion have a relatively high risk of acute restenosis. This study indicates how patients with relatively high risk of acute restenosis may be identified.</p

Complement Activation Selectively Potentiates the Pathogenicity of the IgG2b and IgG3 Isotypes of a High Affinity Anti-Erythrocyte Autoantibody

By generating four IgG isotype-switch variants of the high affinity 34–3C anti-erythrocyte autoantibody, and comparing them to the IgG variants of the low affinity 4C8 anti-erythrocyte autoantibody that we have previously studied, we evaluated in this study how high affinity binding to erythrocytes influences the pathogenicity of each IgG isotype in relation to the respective contributions of Fcγ receptor (FcγR) and complement. The 34–3C autoantibody opsonizing extensively circulating erythrocytes efficiently activated complement in vivo (IgG2a = IgG2b > IgG3), except for the IgG1 isotype, while the 4C8 IgG autoantibody failed to activate complement. The pathogenicity of the 34–3C autoantibody of IgG2b and IgG3 isotypes was dramatically higher (>200-fold) than that of the corresponding isotypes of the 4C8 antibody. This enhanced activity was highly (IgG2b) or totally (IgG3) dependent on complement. In contrast, erythrocyte-binding affinities only played a minor role in in vivo hemolytic activities of the IgG1 and IgG2a isotypes of 34–3C and 4C8 antibodies, where complement was not or only partially involved, respectively. The remarkably different capacities of four different IgG isotypes of low and high affinity anti-erythrocyte autoantibodies to activate FcγR-bearing effector cells and complement in vivo demonstrate the role of autoantibody affinity maturation and of IgG isotype switching in autoantibody-mediated pathology