Estimation of red cell flow microvessels: consequences of the Baker-Wayland spatial averaging model

The dual sensor cross-correlation method of H. Wayland and P.C. Johnson [1967), J. Appl. Physiol. 22, 333-337) has become a standard technique for determining the velocity of red blood cells (RBCs) in glass tubes and blood vessels. M. Baker and H. Wayland [1974), Microvasc. Res. 7, 131-143) found that under a variety of conditions the ratio of dual sensor velocity at the centerline of a glass tube to the blood velocity averaged over the lumen was close to 1.6. They provided an explanation of this factor based on spatial averaging of RBC velocity vertically through the tube as well as laterally across the face of the sensor. Their spatial averaging model could also account for the apparent blunting of RBC velocity profiles determined with the dual sensor technique. We used Baker and Wayland's spatial averaging model to calculate how the above velocity ratio depends on sensor size. A nonlinear relation between the velocity ratio and sensor size was found such that the velocity ratio varied from 1.6 to 1.33 as the ratio of sensor width to vessel or tube diameter was varied from 0 to 1. These results also hold for vessels or tubes of elliptic cross section. Some investigators have found that the velocity of red cells near the walls of blood vessels can be a substantial fraction of centerline velocity which suggests that RBC velocity distributions can be blunter than a Poiseuille distribution. We repeated the above calculation for blunted parabolic profiles and we found that the velocity ratio ranged from 1 for plug flow to 1.6 for Poiseuille flow. These calculations show that reliable estimates of RBC flow from dual sensor centerline velocity measurements require one to take into account the relative size of the sensor and blood vessel diameter as well as the bluntness of the RBC velocity distribution.     

A comparison of the Outcome Questionnaire‐45 and Outcome Questionnaire‐30 in classification and prediction of treatment outcome

Recent research has found that measuring, monitoring and providing therapists with feedback about their clients' treatment progress improves treatment outcome. This study assessed the level of agreement between two outcome measures used to measure and monitor treatment progress. The Outcome Questionnaire (OQ‐45) was compared with a shorter, derivative measure, the OQ‐30. Each measure has an associated feedback system, which provides therapists with feedback about their clients' treatment progress. The OQ‐45 and the OQ‐30 demonstrated high levels of agreement in measurement of client outcome. The OQ‐45 feedback system emerged as the most accurate and clinically useful method for providing therapists with feedback about their clients' predicted treatment outcomes. Copyright © 2006 John Wiley & Sons, Ltd.     

Circulating melanoma-associated antigens in ocular melanoma

A pilot study was performed to test for melanoma-associated antigens (MAAgs) in the sera of patients with localized uveal melanoma, using monoclonal antibodies (MoAbs). Both whole sera and polyethylene glycol (PEG) 2.5% serum precipitates from 18 patients with clinically localized uveal melanoma and two patients with localized invasive conjuctival melanoma were analyzed for two human cutaneous MAAgs by an enzyme-linked immunosorbent assay (ELISA). These antigens could not be identified when whole sera were used. However, after PEG precipitation, a MoAb specific for the p210 MAAg reacted with four of 20 patient samples and none of 17 controls. A second MoAb specific for the p97a MAAg reacted with one of 20 patients and none of 17 controls. These findings indicate the existence of antigens common to both uveal and cutaneous melanoma and suggest that the refinement of assays to screen sera with a battey of MoAbs may be of value in diagnosing and/or monitoring patients with uveal melanoma. Circulating immune complexes were detected in the sera of six patients but did not correlate with any clinical features or with the presence or absence of detectable MAAgs.     

Treatment characteristics of psychiatric programs that correlate with patient community adjustment

This large Veterans Administration cooperative study sought to identify the ward milieu characteristics of effective psychiatric programs. It was developed as a multivariable, correlational study that involved systematic observations of program characteristics and outcome effectiveness of wards as they operated in their usual manner. Seventy-nine wards in 18 hospitals provided 11,283 patients eligible for follow-up. Eleven treatment characteristics were found to be correlated to patients' community adjustment 3 months after discharge. These characteristics were classified into five general categories: Patient-staff interaction, patient activities, medication practices, ward physical environment, and nursing staff rotation. The major conclusions are: wards do differ in their effectiveness as measured by ratings of patient posthospital adjustment; and treatment characteristics make a difference in program effectiveness as measured by patients' posthospital adjustment.     

Severity of demyelination in vivo correlates with serum myelination inhibition activity in guinea pigs having a new form of experimental allergic encephalomyelitis

Guinea pigs received a suboptimal transfer of lymphocytes sensitized to myelin basic protein (BP) and were then immunized with guinea pig BP, BP plus chicken brain or chicken myelin, or chicken brain alone. Sera from these animals were tested for the presence of myelinotoxic antibodies, as detected by the myelination inhibition assay. Myelination inhibition activity correlated with the histologic severity of demyelination.     

Common Sheath Reimplantation Yields Excellent Results in the Treatment of Vesicoureteral Reflux in Duplicated Collecting Systems

Purpose

We evaluated our 10-year experience with the surgical treatment of vesicoureteral reflux in uncomplicated duplicated collecting systems.

Materials and Methods

Between 1984 and 1994, 54 refluxing renal units (8 bilateral) in 37 female and 9 male patients required surgery. Patient age ranged from 7 months to 17 years (average 4.9 at surgery). Postoperative followup (average 14.2 months) included voiding cystourethrography and renal sonography or excretory urography.

Results

Common sheath ureteral reimplantation via an intravesical approach was performed in 48 of the 54 refluxing renal units. Of the remaining 6 renal units detrussorrhaphy was performed in 4, and ureteroureterostomy combined with ureteral reimplantation and partial lower pole nephrectomy were done in 1 each. Two treated renal units had persistent postoperative vesicoureteral reflux, which resolved after subureteral polytetrafluoroethylene (Teflon) injection. No renal unit had postoperative hydronephrosis. Contralateral reflux was identified in 1 patient who underwent unilateral reimplantation. Our overall success rate was 96 percent for the surgical correction of vesicoureteral reflux in uncomplicated duplicated collecting systems. Common sheath reimplantation had a 98 percent success rate.

Conclusions

Although a duplicated collecting system increases the risk for surgical treatment, the presence of a duplication anomaly does not adversely affect surgical outcome. Modifications of procedures commonly performed in the surgical treatment of single system reflux to accommodate common sheath reimplantation have excellent surgical results with minimal morbidity.     

The retained penile prosthesis reservoir: a risk

Complications associated with penile prostheses include malfunction, infection, and patient dissatisfaction. We present a rare complication of a retained abdominal reservoir eroding into the bladder and causing irritative voiding symptoms several years after the removal of the penile components of a three-piece penile prosthesis.     

Cardiometabolic risk reduction in an intensive cardiovascular health program

Background and aimsInsulin and leptin are important markers of insulin resistance and vascular inflammation in metabolic and cardiovascular diseases. This study evaluated changes in circulating levels of insulin and leptin during a cardiovascular health program to improve our understanding of cardiometabolic risk reduction.Methods and resultsParticipants (n = 76) completed a prospective, nonrandomized program designed to stabilize or reverse progression of coronary artery disease through dietary changes, exercise, stress management, and group support. Controls (n = 76) were matched to participants based on age, gender, and disease status. Traditional cardiovascular risk factors were assessed at baseline, 12 weeks, and 52 weeks by standard methods. Dietary data were collected by 72-h recall and evaluated by Food Processor^® v8.4.0. Ultrasensitive insulin and leptin levels were measured by radioimmunoassay. Participants successfully reduced their total caloric intake from >2000 calories per day to ～1700 calories per day (p < 0.05 compared to controls), lowered daily fat intake by >60% (p < 0.001 compared to controls), and increased carbohydrate intake by >30% (p < 0.001). Repeated-measures ANOVA indicated significant beneficial changes (p < 0.001 compared to controls) in plasma insulin (?19%) and leptin (?33%) during the lifestyle program, as well as improvement in traditional cardiovascular risk factors. Response was similar between men and women for most risk factors and was not markedly influenced by medication use.ConclusionLifestyle changes focusing on diet, physical activity, and stress reduction can successfully modify both cardiovascular and metabolic risk factors, with the potential to mediate cardiometabolic risk through beneficial anti-inflammatory and anti-oxidative effects on the vasculature.     

Prostacyclin analogs stimulate receptor-mediated cAMP synthesis and ATP release from rabbit and human erythrocytes

Objectives: The purpose of this study was to establish that the prostacyclin (PGI₂) receptor (IP receptor) is present on rabbit and human erythrocytes and that its activation stimulates cyclic adenosine monophosphate (cAMP) synthesis and adenosine triphosphate (ATP) release. Methods: The effect of incubation of erythrocytes with the active PGI₂ analogs, iloprost or UT‐15C, on cAMP levels and ATP release was determined in the absence and presence of the IP receptor antagonist, CAY10441. Western analysis was used to determine the presence of the IP receptor on isolated membranes. To establish that effects of PGI₂ analogs were not due to prostaglandin E₂(PGE₂) receptor activation, the effect of PGE₂ on cAMP levels and ATP release was determined. Results: Rabbit and human erythrocytes possess IP receptors. Iloprost and UT‐15C stimulated increases in cAMP and ATP release that were prevented by the IP receptor antagonist, CAY10441. PGE₂ did not stimulate cAMP accumulation or ATP release and did not inhibit iloprost‐induced increases in cAMP. Conclusions: This study establishes that the IP receptor is present on rabbit and human erythrocytes and that its activation results in increases in cAMP and ATP release. These results suggest a novel mechanism by which PGI₂ and its active analogs, when administered pharmacologically, could produce vasodilation.