A study of confidential unit exclusion

The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse.     

Suppression of diamine oxidase activity enhances postresection ileal proliferation in the rat

To assess the influence of diamine oxidase activity on the adaptive process of the small bowel after resection, we administered aminoguanidine, a potent diamine oxidase inhibitor, to rats for 10 days after either small bowel transection (n = 5) or 80% jejunoileal resection (n = 7). Five or more additional animals from each group received saline as controls. Ileal mucosal homogenates from the resection group receiving aminoguanidine, when compared with those from resection controls, showed no diamine oxidase activity with increased putrescine content and ornithine decarboxylase activity. Mucosal proliferation, as measured by mucosal mass, protein content, and deoxyribonucleic acid content, was greater in the resected animals receiving aminoguanidine when compared with that of resection controls. Sucrase activity per gram of mucosa was almost identical in both resection groups. These results show that the suppression of diamine oxidase during the postresection adaptive period results in enhanced mucosal proliferation with no effect on mucosal functional differentiation. Diamine oxidase may play a regulatory role in adaptive intestinal proliferation.     

Pharmacokinetic Interaction between Ritonavir and Indinavir in Healthy Volunteers

The pharmacokinetic interaction between indinavir and ritonavir was evaluated in five groups of healthy adult volunteers to explore the potential for twice-daily (b.i.d.) dosing of this combination. All subjects received 800 mg of indinavir every 8 h (q8h) on day 2. In addition, subjects in group I received one dose of 800 mg of indinavir on day 1 and 800 mg of indinavir q8h on day 17. Subjects in Groups II and IV each received one dose of 600 mg of indinavir on days 1 and 17, and subjects in groups III and V each received one dose of 400 mg of indinavir on days 1 and 17. During days 3 to 17, ritonavir placebo or ritonavir at 200, 300, 300, or 400 mg q12h was given to groups I, II, III, IV, and V, respectively. Ritonavir at steady state probably inhibited the cytochrome P-450 3A metabolism of indinavir and substantially increased plasma indinavir concentrations, with the area under the plasma concentration-time curve (AUC) increasing up to 475% and the peak concentration in serum (C_max) increasing up to 110%. The C_max/trough concentration ratio decreased from 50 in standard q8h regimens to less than 14 when indinavir was administered with ritonavir. For a constant indinavir dose, an increase in the ritonavir dose yielded similar indinavir AUCs, C_maxs, and concentrations at 12 h (C₁₂s). For a constant ritonavir dose, an increase in the indinavir dose resulted in approximately proportional increases in the indinavir AUC, less than proportional increases in C_max, and slightly more than proportional increases in C₁₂. Ritonavir reduced between-subject variability in the indinavir AUC and trough concentrations and did not affect indinavir renal clearance. With the altered pharmacokinetic profile, indinavir likely could be given as a b.i.d. combination regimen with ritonavir. This could potentially improve patient compliance and thereby reduce treatment failures.     

Pulsed-field gel electrophoresis genotyping of Taylorella equigenitalis isolates collected in the United States from 1978 to 2010

Taylorella equigenitalis is the etiologic agent of contagious equine metritis (CEM), a venereal disease of horses. A total of 82 strains of T. equigenitalis isolated in the United States were analyzed by pulsed-field gel electrophoresis (PFGE) after digestion of genomic DNA with restriction enzyme ApaI. Twenty-eight of those strains isolated from horses in the 2009 U.S. outbreak (CEM09) were further analyzed with NotI and NaeI enzymes. When ApaI alone was used for analysis, the 82 isolates clustered into 15 different genotypes that clearly defined groups of horses with known epidemiological connections. The PFGE profiles of the CEM09 isolates were indistinguishable after digestion with ApaI, NotI, and NaeI and did not match those of isolates from previous U.S. outbreaks in 1978 and 2006 or of any other isolate from the National Veterinary Services Laboratories (NVSL) culture library. Coupled with the fact that the CEM09 isolates are epidemiologically related, these results suggest a common source for the outbreak not linked to previous occurrences of CEM in the United States.     

Mast cells are an essential hematopoietic component for polyp development

It is generally agreed that most colon cancers develop from adenomatous polyps, and it is this fact on which screening strategies are based. Although there is overwhelming evidence to link intrinsic genetic lesions with the formation of these preneoplastic lesions, recent data suggest that the tumor stromal environment also plays an essential role in this disease. In particular, it has been suggested that CD34(+) immature myeloid precursor cells are required for tumor development and invasion. Here we have used mice conditional for the stabilization of beta-catenin or defective for the adenomatous polyposis coli (APC) gene to reinvestigated the identity and importance of tumor-infiltrating hematopoietic cells in polyposis. We show that, from the onset, polyps are infiltrated with proinflammatory mast cells (MC) and their precursors. Depletion of MC either pharmacologically or through the generation of chimeric mice with genetic lesions in MC development leads to a profound remission of existing polyps. Our data suggest that MC are an essential hematopoietic component for preneoplastic polyp development and are a novel target for therapeutic intervention.     

Rhinovirus-associated hospitalizations in young children

BACKGROUND: Rhinoviruses frequently cause the common cold but have not been considered important causes of acute respiratory hospitalizations in children. METHODS: A population-based surveillance study was performed among children <5 years of age who were hospitalized with respiratory symptoms or fever and who resided within counties encompassing Nashville, Tennessee, or Rochester, New York, from October 2000 through September 2001. Data collected included questionnaires, nasal and throat swabs for viral culture and polymerase chain reaction testing, and chart review. Rates of rhinovirus-associated hospitalizations were calculated. RESULTS: Of 592 children enrolled, 156 (26%) were rhinovirus positive, representing 4.8 (95% confidence interval [CI], 4.3-5.2) rhinovirus-associated hospitalizations/1000 children. Age-specific rates per 1000 children were 17.6 (95% CI, 14.9-20.6) for 0-5-month-olds, 6.0 (95% CI, 5.0-7.0) for 6-23-month-olds, and 2.0 (95% CI, 1.6, 2.4) for 24-59-month-olds (P<.01). Children with a history of wheezing/asthma had significantly more rhinovirus-associated hospitalizations than those without a history (25.3/1000 children [95% CI, 21.6-29.5/1000 children] vs. 3.1/1000 children [95% CI, 2.7-3.5/1000 children]). CONCLUSIONS: Rhinoviruses were associated with nearly 5 hospitalizations/1000 children <5 years of age and were highest in children with a history of wheezing/asthma.     

Evaluation of tetramethylrhodamine and black hole quencher 1 labeled probes and five commercial amplification mixes in TaqMan real-time RT-PCR assays for respiratory pathogens

Tetramethylrhodamine (TAMRA^®) and black hole quencher 1 (BHQ1^®) quenched probes and five one-step RT-PCR kits were evaluated in TaqMan^® real-time RT-PCR assays for detection of respiratory pathogens. The intra-assay variability of the BHQ1^® probes were 1.2–2.8-fold lower than those of the TAMRA^® probes. All kits amplified the specific targets, but differed in their sensitivity by up to 3 orders of magnitude. The AgPath-ID™ kit provided the best overall performance for all assay targets.