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John Anderson

Publications and source records attributed to John Anderson.

At least 37 records · Page 2Linked to original sources
PubMed2005

Cholesterol emboli-induced renal failure and gastric ulcer after thrombolytic therapy.

Cholesterol embolization syndrome is a rare but devastating complication of thrombolysis. Clinical presentations are variable, which has resulted in labeling this syndrome as the great masquerader. Almost every organ in the body may be affected, but the syndrome commonly involves the kidney, skin, central nervous system, and gastrointestinal tract. Treatment is mainly supportive, with an emphasis on reducing the risk of recurrence. The case presented is a unique one of thrombolytic-induced cholesterol embolization syndrome causing renal failure, in which the diagnosis was supported by a biopsy of a gastric ulcer.

Aged↗
PubMed2005

Open access in primary care: results of a North Carolina pilot project.

OBJECTIVE: Appointment delays impede access to primary health care. By reducing appointment delays, open access (OA) scheduling may improve access to and the quality of primary health care. The objective of this pilot study was to assess the potential impact of OA on practice and patient outcomes by using pilot-study data from 4 North Carolina primary care practices. METHODS: We conducted an interrupted time-series pilot study of 4 North Carolina primary care practices (2 family medicine and 2 pediatric practices) participating in a quality-improvement (QI) collaborative from May 2001 to May 2002. The year-long collaborative comprised 25 practices and consisted of three 2-day meetings led by expert faculty, monthly data feedback, and monthly conference calls. Our main outcome measures were appointment delays, appointment no-shows, patient satisfaction, continuity of care, and staff satisfaction during the 12-month study period. RESULTS: Providers in all 4 practices successfully implemented OA. On average, providers reduced their delay to the third available preventive care appointment from 36 to 4 days. No-show rates declined (first quarter [Q1] rate: 16%; fourth quarter [Q4] rate: 11%; no-show reduction: 5% [95% confidence interval: 1%, 10%]), and overall patient satisfaction improved (Q1: 45% rated overall visit quality as excellent; Q4: 61% rated overall visit quality as excellent; change in satisfaction: 16% [95% confidence interval: 0.2%, 30%]). Continuity of care followed a similar pattern of improvement, but the change was not statistically significant. Staff satisfaction neither improved nor declined. CONCLUSIONS: This pilot study suggests that primary care practices can implement OA successfully by using QI-collaborative methods. These results provide preliminary evidence that OA may improve practice and patient outcomes in primary care. These analyses should be repeated in larger groups of practices with longer follow-up.

Appointments and Schedules↗
PubMed2005

Serologic surveillance for selected viral agents in captive and free-ranging populations of Arabian oryx (Oryx leucoryx) from Saudi Arabia and the United Arab Emirates.

A total of 294 sera collected between 1999 and 2001 from eight captive and one free-ranging herds of Arabian oryx (Oryx leucoryx) distributed in Saudi Arabia (SA) and the United Arab Emirates (UAE) were assayed for antibodies against 13 selected viral agents. Arabian oryx have been exposed to bluetongue virus (BTV), epizootic hemorrhagic disease virus (EHDV), rinderpest virus (RPV), bovine respiratory syncytial virus (BRSV), bovine adenovirus 3 (BAV-3), cervid herpesvirus-1, foot-and-mouth disease virus, equine herpesvirus 9, and bovine viral diarrhea virus. The high seroprevalence to BTV and EHDV in the UAE and SA indicates that Arabian oryx are likely to be susceptible to infection by these viruses and therefore could act as a source of virus to vectors during the infective stage of infection. Moreover, antibodies were detected against RPV and BRSV in sera from SA and against BAV-3 in sera from the UAE. No antibodies were found against bovine herpesvirus-1, caprine herpesvirus-1, enzootic bovine leucosis virus, and peste des petits ruminants virus. On the basis of these results, caution should be applied when considering translocation of Arabian oryx, and only those proven to be free of infectious agents that might present a risk to other species should be moved.

Animals↗
PubMed2005

Physician and patient based outcomes following surgical resection of Haglund's deformity.

Calcaneal ostectomy is the benchmark for definitive surgical treatment in patients with Haglund's syndrome, despite conflicting and unpredictable study results. The current study's hypothesis is that when adequate bone is resected and outcomes are evaluated using validated scores, calcaneal ostectomy can give reliable and predictable results. Thirty six consecutive patients (39 feet) underwent calcaneal ostectomy for Haglund's deformity between 1998 and 2002. All patients were evaluated with the AOFAS score and SF-36v2 questionnaire. The mean time to follow-up was 51 months. The mean AOFAS score following surgery was 86/100 points; the mean SF-36v2 score following surgery was 144/152. Six of the 36 patients interviewed, however, would not recommend the procedure to others, citing mainly prolonged recovery time. Calcaneal ostectomy achieves good-to-excellent results in the treatment of Haglund's deformity when appropriate amounts of bone are excised. However, patients must be made aware of the necessary time to recovery, between 6 months and 2 years.

Achilles Tendon↗
PubMed2004

Inhibiting primary effusion lymphoma by lentiviral vectors encoding short hairpin RNA.

We use lentiviral-delivered RNA interference (RNAi) to inhibit the growth of a model of primary effusion lymphoma (PEL) in vitro and in vivo. RNAi is a phenomenon allowing the sequence-specific targeting and silencing of exogenous and endogenous gene expression and is being applied to inhibit viral replication both in vitro and in vivo. We show that silencing of genes believed to be essential for the Kaposi sarcoma-associated herpesvirus (KSHV) latent life cycle (the oncogenic cluster) has a varied effect in PEL cell lines cultured in vitro, however, concomitant silencing of the viral cyclin (vcyclin) and viral FLICE (Fas-associating protein with death domain-like interleukin-1beta-converting enzyme) inhibitory protein (vFLIP) caused efficient apoptosis in all PEL lines tested. We demonstrate that in a murine model of PEL, lentiviral-mediated RNA interference both inhibits development of ascites and can act as a treatment for established ascites. We also show that the administered lentiviral vectors are essentially limited to the peritoneal cavity, which has advantages for safety and dosage in a therapeutic setting. This shows the use of lentiviral-mediated RNA interference in vivo as a potential therapeutic against a virally driven human cancer.

Animals↗
PubMed2004

Effect of interferon-alpha2b therapy on St. Louis viral meningoencephalitis: clinical and laboratory results of a pilot study.

The safety and potential efficacy of interferon (IFN)-alpha2b were determined for 15 patients during an outbreak of meningoencephalitis due to St. Louis encephalitis (SLE) virus. Clinical and laboratory results were compared with those of 17 untreated patients who were admitted to the same hospital during this nonrandomized preliminary trial. Quadriplegia, quadriparesis, or respiratory insufficiency persisted after the first week of hospitalization, for 11 of 17 untreated patients and for only 2 of 15 treated patients. These complications existed after the second week of hospitalization for 5 of the 17 untreated patients and for 1 of the 15 treated patients. Transient neutropenia and/or mild hepatitis occurred in 11 treated patients. Early initiation of IFN-alpha2b therapy may reduce the severity and duration of complications due to previously untreatable flavivirus meningoencephalitis. A prospective randomized controlled trial is warranted.

Adult↗
PubMed2004

Comparing the efficacy and safety of a novel monophasic waveform delivered by the passive implantable atrial defibrillator with biphasic waveforms in cardioversion of atrial fibrillation.

BACKGROUND: The passive implantable atrial defibrillator (PIAD) (with no battery or discharging capacitor and powered transcutaneously by radio-frequency energy) delivering a novel monophasic low-tilt waveform is more efficacious than the standard monophasic waveform at atrial defibrillation. Standard biphasic (STB) waveforms, however, are more efficacious and safer than monophasic waveforms. This study compared the efficacy and safety of the PIAD waveform with biphasic waveforms. METHODS AND RESULTS: Sustained atrial fibrillation (AF) was induced by rapid atrial pacing. Cardioversion was attempted via 2 atrial defibrillation leads. The efficacy of the PIAD was compared with 3 biphasic waveforms (standard, single rounded, and double rounded) at varying voltage settings in 10 pigs. After a synchronized shock, hemodynamic changes between the PIAD, standard biphasic, and monophasic waveforms were compared at 1.5 and 3.0 J in 12 pigs. Myocardial injury (biochemical and histological) after ten 5-J PIAD shocks was compared with a no-shock group in 14 pigs. The PIAD 100-V setting was significantly more efficacious than the STB (100/-50 V: 100% [1.88+/-0.02 J] versus 90% [0.89+/-0.0 J]; P=0.025). No arrhythmic, hemodynamic, or myocardial injury was observed with the PIAD waveform. CONCLUSIONS: Defibrillation with the PIAD is more efficacious than with the STB waveform and appears safe. This device could provide a more effective option for cardioversion.

Animals↗
PubMed2004

The Brn-3b transcription factor regulates the growth, behavior, and invasiveness of human neuroblastoma cells in vitro and in vivo.

Neuroblastomas are the second most common solid tumor in children but the molecular mechanisms underlying the initiation and progression of this disease are poorly understood. We previously showed that the Brn-3b transcription factor is highly expressed in actively proliferating neuroblastoma cells but is significantly decreased when these cells are induced to differentiate. In this study, we analyzed the effects of manipulating Brn-3b levels in the human neuroblastoma cell line, IMR-32 and showed that constitutive overexpression of Brn-3b consistently increased cellular growth and proliferation in monolayer as well as in an anchorage-independent manner compared with controls whereas stably decreasing Brn-3b can reduce the rate of growth of these cells. Cells with high Brn-3b also fail to respond to growth inhibitory retinoic acid, as they continue to proliferate. Moreover, Brn-3b levels significantly modified tumor growth in vivo with elevated Brn-3b resulting in faster tumor growth in xenograft models whereas decreasing Brn-3b resulted in slower growth compared with controls. Interestingly, elevated Brn-3b levels also enhances the invasive capacity of these neuroblastoma cells with significantly larger numbers of migrating cells observed in overexpressing clones compared with controls. Because invasion and metastasis influence morbidity and mortality in neuroblastoma and so significantly affect the course and outcome of neuroblastomas, this finding is very important. Our results therefore suggest that Brn-3b transcription factor contributes to proliferation of neuroblastoma cells in vivo and in vitro but may also influence progression and/or invasion during tumorigenesis. It is possible that decreasing Brn-3b levels may reverse some effects on growth and proliferation of these cells.

Cell Adhesion↗
PubMed2004

Trauma during pregnancy: an analysis of maternal and fetal outcomes in a large population.

OBJECTIVE: This study was undertaken to determine the occurrence rates, outcomes, risk factors, and timing of obstetric delivery for trauma sustained during pregnancy. STUDY DESIGN: This is a retrospective cohort study of women hospitalized for trauma in California (1991-1999). International Classification of Disease, ninth revision, Clinical Modification codes, and external causation codes for injury were identified. Maternal and fetal/neonatal outcomes were analyzed for women delivering at the trauma hospitalization (group 1), and women sustaining trauma prenatally (group 2), compared with nontrauma controls. Injury severity scores and injury types were used to stratify risk in relation to outcome. Statistical comparisons are expressed as odds ratios (ORs) with 95% CIs. RESULTS: A total of 10,316 deliveries fulfilling study criteria were identified in 4,833,286 total deliveries. Fractures, dislocations, sprains, and strains were the most common type of injury. Group 1 was associated with the worst outcomes: maternal death OR 69 (95% CI 42-115), fetal death OR 4.7 (95% CI 3.4-6.4), uterine rupture OR 43 (95% CI 19-97), and placental abruption OR 9.2 (95% CI 7.8-11). Group 2 also resulted in increased risks at delivery: placental abruption OR 1.6 (95% CI 1.3-1.9), preterm labor OR 2.7 (95% CI 2.5-2.9), maternal death OR 4.4 (95% CI 1.4-14). As injury severity scores increased, outcomes worsened, yet were statistically nonpredictive. The type of injury most commonly leading to maternal death was internal injury. The risk of fetal, neonatal, and infant death was strongly influenced by gestational age at the time of delivery. CONCLUSION: Women delivering at the trauma hospitalization (group 1) had the worst outcomes, regardless of the severity of the injury. Group 2 women (prenatal injury) had an increased risk of adverse outcomes at delivery, and therefore should be monitored closely during the subsequent course of the pregnancy. This study highlights the need to optimize education in trauma prevention during pregnancy.

Abortion, Spontaneous↗
PubMed2004

Steady-state and frequency-domain lifetime measurements of an activated molecular imprinted polymer imprinted to dipicolinic acid.

We recently demonstrated the synthesis and fluorescence activity associated with an optical detector incorporating a molecular imprinted polymer (MIP). Steady-state and time-resolved (lifetime) fluorescence measurements were used to characterize the binding activity associated with MIP microparticles imprinted to dipicolinic acid (DPA). DPA is a unique biomarker associated with the sporulation phase of endospore-forming bacteria. Vinylic monomers were polymerized in a dimethylformamide solution containing DPA as a template. The resulting MIP was then pulverized and sorted into small microscale particles. Tests were conducted on replicate samples of biologically active cultures representing both vegetative stationary phase and sporulation phase of Bacillus subtilis in standard media. Samplers were adapted incorporating the MIP particles within a dialyzer cartridge (500 MW). The permeability of the dialyzer membrane permitted diffusion of lighter molecular weight constituents from microbial media effluents to enter the dialyzer chamber and come in contact with the MIP. Results showed dramatic (10-fold over background) steady-state fluorescence changes (as a function of excitation, emission and intensity) for samples associated with high endospore biomass (DPA), and a frequency-domain lifetime of 5.3 ns for the MIP-DPA complex.

Bacillus subtilis↗
PubMed2004

Multiple choice questions revisited.

MCQs of the multiple true/false (MTF) variety were widely used in summative assessment 25 years ago. They could test a number of skills in addition to recall of factual knowledge, and were reliable, discriminatory, reproducible and cost-effective. However, there are now considerable doubts about their construct validity, mainly because of the varying responses of examinees to negative countermarking and the 'don't know' option, and the strategies they use when sitting examinations. Extended matching and one-from-five questions are now preferable, and negative countermarking is outmoded. MTF questions are still valuable in formative assessment and revision but are not recommended for summative examinations.

Education, Medical, Undergraduate↗
PubMed2004

Seven to 10 years followup of an anatomic hip prosthesis: an international study.

Hypothetically, hydroxyapatite-coated anatomic-shaped femoral stems and hemispheric acetabular cups should improve biologic fixation of the implant and strength transmission to the bone, improving unsatisfactory results of the first cementless hip prosthesis focused on the stress-shielding phenomenon at the femur and failure of the threaded acetabular cups. A consecutive series of 312 patients who had primary Anatomique Benoist Giraud hip prostheses unilaterally implanted were followed up. We analyzed the clinical and radiographic results and report the outcomes 7-10 years after implantation. Two hundred thirty-two patients were assessed at 7-10 years. The survival rate for the implant was 96.8%; 77.2% of patients had no pain, 72.4% maintained total mobility, and 62.9% were able to walk without restrictions. However, radiologic assessment shows that problems improved but did not disappear. More than 55% of femurs had signs of proximal stress-shielding develop. More important, substantial polyethylene wear was observed in at least 62% of the acetabular inserts at 7-10 years followup.

Adult↗
PubMed2004

Prospective evaluation of a first trimester screening program for Down syndrome and other chromosomal abnormalities using maternal age, nuchal translucency and biochemistry in an Australian population.

BACKGROUND: A combination of maternal age and ultrasound assessment of the nuchal translucency (NT) has been used in the first trimester to screen for chromosomal abnormality. In the United Kingdom, the addition of NT screening was shown to be beneficial. AIMS: To report the sensitivity of combined first trimester biochemistry and ultrasound screening for Down syndrome in an Australian private practice specialising in obstetric ultrasound. METHODS: A prospective study in a private obstetric ultrasound practice. Over 22 months, 2121 patients were screened and data was analysed for sensitivity (detection) and false positive rates for all chromosome abnormalities. RESULTS: There were 17 chromosomal abnormalities, five of which were Down syndrome. Using maternal age alone or age and biochemistry, four of the Down syndrome cases were detected for a 29 and 19% false positive rate, respectively. Using age and NT or age, NT and biochemistry, all the Down syndrome cases were detected, for a false positive rate of 5.7 and 7.2%, respectively. The difference in detection rates for Down syndrome or other chromosomal abnormalities, using the four screening methods, did not reach statistical significance. However, the false positive rates in screening methods without ultrasound to assess the NT was significantly higher (P < 0.01). CONCLUSIONS: A combination of maternal age, NT and maternal serum biochemistry gives a high detection rate for both trisomy 21 and other chromosomal abnormalities. Down syndrome screening using either maternal age alone or age in combination with first trimester biochemistry conferred screen positive rates significantly higher than when combined with NT.

Adolescent↗
PubMed2003

Novel passive implantable atrial defibrillator using transcutaneous radiofrequency energy transmission successfully cardioverts atrial fibrillation.

BACKGROUND: Conventional methods for cardioversion of atrial fibrillation (AF) to sinus rhythm have numerous difficulties. A novel method for cardioversion using the passive implantable atrial defibrillator (PIAD) was tested in acute animal models. This device does not have a battery or a capacitor to store energy and is activated by transferring RF energy across the skin from an external transmitter to the subcutaneously implanted defibrillator. On activation, a novel monophasic shock waveform with 5% tilt is delivered to the heart via 2 intracardiac defibrillation leads. METHODS AND RESULTS: Cardioversion attempts with the device were assessed in 2 phases: a feasibility and efficacy study and randomized comparison against standard waveforms. Defibrillation leads were placed transvenously into the distal coronary sinus and the right atrial appendage. These were connected to the subcutaneously implanted PIAD. Sustained AF was induced by rapid atrial pacing. The transmitter coil was placed on the skin overlying the defibrillator, and defibrillation synchronized to the R wave was attempted. The method was found to be efficacious at very low voltage and energy, with 100% cardioversion success observed for 10-ms 100-V shocks (mean energy, 1.54+/-0.02 J). The PIAD waveform had a higher cardioversion success rate than a truncated, 70% tilt monophasic exponential pulse (100 V, 100% versus 78.0+/-7.57%; P=0.001). There were no postshock complications. CONCLUSIONS: Considering these animal results, this method is promising for cardioverting AF in symptomatic patients.

Animals↗
PubMed2003

Straight talk. New approaches in healthcare. Managing medical research: strategies for success.

Medical research programs are under significant pressure both from declines in the growth rates of government funding as well as from increases in government oversight of the privacy and safety of human research subjects. To cope, forward-thinking healthcare institutions are applying the same no-nonsense business rules to their research programs that they apply to other programs and departments. Modern Healthcare and PricewaterhouseCoopers present Straight Talk. In the session on medical research, we discuss how and why the world of medical research is changing, and what health systems should do to manage research programs successfully. The session was held on March 4, 2003 at Modern Healthcare's Chicago headquarters. Charles S. Lauer, publisher of Modern Healthcare, was the moderator.

Academic Medical Centers↗
PubMed2003

Chromosomal imbalances in pleomorphic rhabdomyosarcomas and identification of the alveolar rhabdomyosarcoma-associated PAX3-FOXO1A fusion gene in one case.

Rhabdomyosarcomas (RMS) are soft tissue sarcomas resembling developing skeletal muscle, and pleomorphic rhabdomyosarcomas (PRMS) are a rare nonpediatric entity. Little molecular cytogenetic information exists for PRMS, and their relationship to other subtypes of rhabdomyosarcoma and other sarcomas is unclear. Chromosomal imbalances were determined in seven well-characterized cases of PRMS using comparative genomic hybridization. The smallest overlapping regions of gain were 1p22 approximately p33 (71%), 7p (43%), 18/18q (43%), and 20/20p (43%), and the regions of loss were 10q23 (71%), 15q21 approximately q22 (57%), 3p, 5q32 approximately qter, and 13 (all 43%). Four of the seven cases had amplicons involving the regions 1p21 approximately p31, 1q21 approximately q25, 3p12, 3q26 approximately qtel, 4q28 approximately q31, 8q21 approximately q23/8q, and 22q. These regions are distinct from those frequently associated with the alveolar subtype, whereas the embryonal subtype without anaplasia is rarely associated with amplification events other than gain/amplification of 8q material. The regions of imbalance appeared more similar to those reported for malignant fibrous histiocytomas (MFH) and osteosarcomas, consistent with the suggestion that PRMS can be considered part of the spectrum of MFH. In addition, one of the cases classified as PRMS showed evidence for the presence of a PAX3-FOXO1A fusion gene, which is characteristic of the alveolar subtype of RMS.

Aged↗