Predictive factors of urinary retention following prostate brachytherapy

PURPOSE: To evaluate the incidence and duration of urinary retention requiring catheterization and the factors predictive for these end points. METHODS AND MATERIALS: Two hundred eighty-two patients treated with prostate brachytherapy alone were evaluated. Clinical and treatment-related factors examined included: age, baseline International Prostate Symptom Score (IPSS), presence of comorbidity, planning ultrasound target volume (PUTV), postimplant prostate CT scan volume, the CT:PUTV ratio, number of seeds inserted, number of needles used, use of neoadjuvant hormones, procedural physician, clinical stage, Gleason score, and pretreatment PSA. Dosimetric quality indicators were also examined. RESULTS: Urinary obstruction after prostate brachytherapy developed in 43 (15%) patients. The median duration of catheter insertion was 21 days (mean 49, range 1-365). Univariate analysis demonstrated that presence of diabetes, preimplant volume, postimplant volume, CT:PUTV ratio, number of needles, and dosimetric parameters were predictive for catheterization. However, in multivariate analysis, only the baseline IPSS, CT:PUTV ratio, and presence of diabetes were significant independent predictive factors for catheterization. CONCLUSION: Baseline IPSS was the most important predictive factor for postimplantation catheterization. The extent of postimplant edema, as reflected by the CT:PUTV ratio, predicted for need and duration of catheterization. The presence of diabetes was predictive for catheterization, but may relate to the absence of prophylactic steroids, and therefore requires further evaluation.     

Donor hepatitis C seropositivity: clinical correlates and effect on early graft and patient survival in adult cadaveric kidney transplantation

The impact of hepatitis C virus-positive donor kidneys on patient survival has not been analyzed in a national study. This study analyzed 20,111 adult (age, > or =16 yr) recipients having solitary cadaveric kidney transplants from adult donors with valid donor hepatitis C serologies from July 1, 1994, to June 30, 1998, in an historical cohort study (the 2000 United States Kidney Data System) of patient survival. Analysis was by the Cox proportional hazards models, which corrected for characteristics thought to affect outcomes. Of 484 kidneys positive for hepatitis C virus serology, 165 (34%) were given to recipients with confirmed negative hepatitis C serologies. Unadjusted 3-yr patient survival was 93% in all recipients of donor hepatitis C-negative kidneys versus 85% in all recipients of donor hepatitis C-positive kidneys (P = 0.01). Among hepatitis C-positive recipients, those who received hepatitis C-positive kidneys had worse survival than recipients of hepatitis C-negative kidneys. Among elderly hepatitis C-negative recipients, those who received hepatitis C-positive kidneys also had worse survival; in fact, all recipients of donor hepatitis C-positive kidneys had increased risk of mortality (P = 0.028). There were no significant interactions between donor hepatitis C positivity and either recipient hepatitis C positivity or older recipient age. The use of hepatitis C-positive kidneys in recipients who were hepatitis C-negative was fairly common and contrary to some current recommendations. Recipients of donor hepatitis C-positive kidneys were at independently increased risk of mortality, with no evidence that any subgroups were less affected.     

Treatment of experimental autoimmune encephalomyelitis with antisense oligonucleotides against the low affinity neurotrophin receptor

Upregulated expression of the low-affinity neurotrophin receptor (p75) in the central nervous system (CNS) during experimental autoimmune encephalomyelitis (EAE) has recently been demonstrated. To investigate whether p75 plays a role in disease pathogenesis, we adopted a gene therapy approach, utilizing antisense oligonucleotides to downregulate p75 expression during EAE. Phosphorothioate antisense oligonucleotides (AS), nonsense oligonucleotides (NS) or phosphate buffered saline (PBS) were injected daily for 18 days after immunization of SJL/J (H-2s)-mice with myelin proteolipid protein (PLP) peptide 139-151. In the AS group, there was a statistically significant reduction in both the mean maximal disease score (1.85 in the AS, 2.94 in the NS and 2.75 in the PBS-groups, respectively, P < 0.025) and in the cumulative disease incidence ( approximately 60% in the AS group and approximately 90% in the control groups). Histological and immunohistochemical analysis showed reduced inflammation and demyelination, as well as reduced p75 expression at the blood-brain barrier (BBB) in the AS-treated mice in comparison with both control groups. There was no difference, however, in p75 expression on neural cells within the CNS between the three groups of mice. We conclude that p75 could play a proactive role in the pathogenesis of EAE and may exert its effect at the level of the BBB.     

Motor execution is necessary to memorize disparity

Binocular saccades in response to briefly flashed, memorized disparate targets (different for the two eyes) become disconjugate following repeated trials. After 15 min of such training, the disconjugacy persists, even when the target to memorize is no longer disparate. This study examines the hypothesis that disparity memorization has a motor basis. We report here three experiments in which subjects were trained for 15-min periods. In experiment 1, subjects made no saccade after target presentation (static training); in experiment 2 subjects intended to make a saccade, but they actually made a saccade in only 10% or 20% of the trials; in experiment 3 subjects made anti-saccades. For all three experiments, the flashed target was disparate and the memory delay for each trial was 1 s. To examine the effects of learning for all three experiments, before and after training, we recorded memory-guided saccades to non-disparate targets (monocular viewing). Experiments 1 and 2 produced inconsistent (before/after training) changes in the disconjugacy of saccades. Thus, the disparity of potential saccade targets had no lasting effect on the disconjugacy of saccades if a saccade was not made. In contrast, the anti-saccades in experiment 3 developed a disconjugacy opposite to the disparity of the remembered target. These findings indicate that the execution of the saccade is necessary to memorize disparity of the target.     

Comparing the effects of nasal synchronized intermittent positive pressure ventilation (nSIPPV) and nasal continuous positive airway pressure (nCPAP) after extubation in very low birth weight infants

In this study we hypothesized that nasal synchronized intermittent positive pressure ventilation (nSIPPV) would provide more ventilatory support than nasal continuous positive airway pressure (nCPAP) in the immediate post-extubation period in very low birth weight (VLBW) infants. We tested this hypothesis by comparing the effects of these two ventilatory techniques on ventilation, gas exchange, and patient inspiratory effort in 11 preterm infants immediately after extubation. All neonates studied (BW: 1141+/-(SEM) 53 g; GA: 28.1+/-(SEM) 0.5 wks) had received mechanical ventilation because of respiratory distress at birth and were extubated by day 14 of life. Nasal SIPPV and nCPAP were applied in random order to each infant after extubation so that each was his/her own control. Both nCPAP and nSIPPV were delivered at end-expiratory pressures (PEEP) of 3 cm H2O. Inspiratory times (Ti) and peak inspiratory pressures set during nSIPPV were the same as those used at the time of extubation. Recordings lasted 45 min in each mode of ventilation. Tidal volume (Vt), minute volume (Ve), respiratory rate (RR), airway pressure (Paw), transcutaneous PO2 (TcPO2) and PCO2 (TcPCO2) as well as phasic esophageal pressure deflections (Pe), as an estimate of inspiratory effort, were measured. The measurements obtained during both modes of ventilation indicated significant differences between the two techniques. Indeed, application of nSIPPV was associated with a statistically significant increase in Vt and Ve. In addition, Pe decreased by 30% during nSIPPV (P<0.01). TcPCO2 was statistically significantly lower during nSIPPV than nCPAP, and RR as well. These data therefore suggest that nSIPPV may provide more ventilatory support than nCPAP in the post-extubation period with less patient inspiratory effort.     

In vitro interaction of quinidine with kaolin and pectin

The adsorption of quinidine onto kaolin was studied as a function of pH in aqueous solutions in which the ionic strength was adjusted to 0.1. The interaction of quinidine with pectin also was investigated in water and in phosphate buffer; the buffer pH and ionic strength were adjusted to 6.5 and 0.1, respectively. The in vitro results indicated that quinidine was adsorbed onto kaolin. At the highest concentration studied, the extent of adsorption increased from 3.64 mg of quinidine adsorbed/g of adsorbent at pH 2.4 to an average of 5.81 mg/g in the pH 5.5-7.5 range. In the presence of electrolytes, the interaction of quinidine with pectin was relatively small (3-13% bound) as compared to studies performed in water (66-90% bound). The data indicate that some quinidine may be adsorbed when this drug is administered concurrently with kaolin-pectin preparations.     

The effects of renal transplantation on peripheral blood dendritic cells

Recent advances allow accurate quantification of peripheral blood (PB) myeloid and plasmacytoid dendritic cell (DC) populations (mDC and pDC, respectively), although the response to renal transplantation (RT) remains unknown. Using flow cytometry, PBDC levels were quantified in patients with end stage renal disease (ESRD) undergoing RT. PBDC levels were significantly reduced in ESRD patients pre-RT compared to healthy controls, with further reduction noted immediately following a hemodialysis session. RT resulted in a dramatic decrease in both subsets, with a greater reduction of pDC levels. Both subset levels were significantly lower than in control patients undergoing abdominal surgery without RT. Subgroup analysis revealed significantly greater mDC reduction in RT recipients receiving anti-lymphocyte therapy, with preferential binding of antibody preparation to this subset. Samples from later time points revealed a gradual return of PBDC levels back to pre-transplant values concurrent with overall reduction of immunosuppression (IS). Finally, PBDC levels were significantly reduced in patients with BK virus nephropathy compared to recipients with stable graft function, despite lower overall IS. Our findings suggest that PBDC levels reflect the degree of IS in renal allograft recipients. Furthermore, PBDC monitoring may represent a novel strategy to predict important outcomes such as acute rejection, long-term graft loss and infectious complications.