Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “OKLAHOMA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,585 records · Page 88Linked to original sources

Regional variation in the presence of canebrake toxin in Crotalus horridus venom.

Reverse-phase HPLC was used to isolate the PLA complex neurotoxin "canebrake toxin" from the venom of Crotalus horridus from northern Florida. Individual venoms from 107 specimens of C. horridus throughout its range were investigated for the presence of the toxin. The distribution of canebrake toxin was limited to two separate regions, including a region of Louisiana, Arkansas and Oklahoma, and a separate region from southeastern South Carolina through eastern Georgia to northern Florida. Four distinct venom types were found and designated Venoms A (neurotoxic), B (hemorrhagic), A + B (neurotoxic and hemorrhagic) and C (lacking in both neurotoxic and hemorrhagic activities).

Animals↗

Mini-implant anchorage for maxillary canine retraction: a pilot study.

INTRODUCTION: This clinical pilot study evaluated the stability, surrounding soft-tissue health, and patient comfort and acceptance of a mini-implant used as anchorage for maxillary permanent canine retraction. METHODS: The study was conducted in the Graduate Orthodontic Clinic of the University of Oklahoma College of Dentistry. The sample comprised 16 subjects who had maxillary first premolars extracted. In each patient, Ortho Implants (IMTEC, Ardmore, Okla) were placed laterally in the maxillary alveolar ridge between the roots of the permanent first molars and the second premolars by an oral surgeon. All retraction was accomplished on 0.017 x 0.025-in stainless steel archwires in 0.022-in slots by using nickel-titanium springs stretched from the implant head to the brackets on the canines. RESULTS: Placement protocol strongly affected the stability of the implants; 1 protocol resulted in the loss of 51% of the implants (19 of 39), and the second protocol resulted in 100% stability (10 of 10). The surrounding soft tissue remained healthy around stable implants and less healthy around implants that were unstable or lost. Patient comfort was excellent in all but 1 patient. Rates of canine retraction were calculated monthly and varied widely from +6.1 to -1.5 mm per month. Excessive crown tipping into the extraction spaces was observed in 4 of the 28 retracted canines and was related to the method of ligation of the canine to the archwire. CONCLUSIONS: Ortho Implants are adequate anchorage for maxillary canine retraction when properly placed.

Adolescent↗

Reducing medical service utilization by encouraging vaccines: randomized controlled trial.

BACKGROUND: Vaccination against influenza is associated with reductions in hospitalizations for heart disease, cerebrovascular disease, pneumonia, or influenza, and the risk of death from all causes during the influenza season. DESIGN: Randomized controlled trial. PARTICIPANTS: All members enrolled in the Blue Cross Blue Shield Association's Government Wide Service Benefit Program in the states of Oklahoma, Rhode Island, Kentucky, California, Arizona, Utah, and Colorado in October 2002. The sample size was 339,220 members. INTERVENTION: Two identical influenza/pneumonia direct mail marketing pieces that encouraged members to receive influenza and pneumococcal vaccinations. The study period was October 15, 2002 through March 15, 2003 when most influenza cases occur. Data were collected in July 2003 and analyzed during August 2003. MAIN OUTCOME MEASURES: Administrative claims based on influenza/pneumonia inpatient admissions and emergency department (ED) visits. RESULTS: The intervention group experienced a 2.62% (p=0.010) higher rate of influenza vaccinations; 4.61% (p=0.080) higher rate of pneumonia vaccinations; 9.67% (p=0.136) lower rate of influenza/pneumonia inpatient admissions; and 22.64% (p=0.002) lower rate of influenza/pneumonia ED visits compared to the control group. The benefit-cost ratio (return on investment) from this intervention was estimated to be US dollar 2.21 per dollar spent. CONCLUSIONS: Administrative claims data suggest that members respond to health plan mailings with an increase in influenza vaccination rates. Health plans can cost-effectively impact medical service utilization and vaccination rates by mailing information to their members.

Adolescent↗

Q & A. [interview].

Elaine and Gary Ostrander spent their youth in New Jersey and New York before heading to Nebraska for their teen years and eventually Washington State for High School and college, as their father moved around in library administration. Elaine was an undergraduate at the University of Washington, a graduate student at the Oregon Health Sciences University and a postdoc with James Wang at Harvard, studying DNA supercoiling. She next went to Berkeley, where she began the canine genome project, initiating the meiotic linkage map and working on human chromosome 21 at the Lawrence Berkeley National Labs. In 1993 she moved to the Fred Hutchinson Cancer Research Center where she is now a Member of the Divisions of Clinical Research and Human Biology. She is also an Affiliate Professor of Genome Sciences and Biology at the University of Washington, and heads the Program in Genetics at the Hutchinson Center. Gary completed his undergraduate degree in Biology at Seattle University, a M.S. degree at Illinois State University and a Ph.D at the University of Washington in Ocean and Fisheries Science. He went on to be a postdoc in the Department of Pathology at the University of Washington Medical School while being mentored by Senitroh Hakomori of the Fred Hutchinson Cancer Research Center and Eric Holmes of the Pacific Northwest Research Foundation. His work focused on using novel aspects of the biology of fishes to address fundamental questions about cancer. He subsequently held both faculty and administrative positions at Oklahoma State University. Since 1996, he has been at the Johns Hopkins University, where he currently holds academic appointments in the Departments of Biology and Comparative Medicine and is the Associate Provost for Research.

Biomedical Research↗

Lung lesions in SCID-bo and SCID-bg mice after intratracheal inoculation with wild-type or leucotoxin-deficient mutant strains of Mannheimia haemolytica serotype 1.

The purpose of this study was to investigate SCID-bg mice engrafted with bovine haematolymphoid tissues (SCID-bo) as a model for studying bovine Mannheimia haemolytica serotype 1- induced pneumonia, in which leucotoxin (LKT) plays a major role. In experiment A, SCID-bo and SCID-bg mice were inoculated intratracheally with either (1) phosphate-buffered saline (PBS), (2) M. haemolytica wild-type strain 89010807N ("LKT(+)WT"), (3) a M. haemolytica leucotoxin-deficient mutant of strain 89010807N ("LKT(-)mutant"), or (4) the M. haemolytica wild-type Oklahoma strain. Mice were killed for examination at intervals between 20 and 44h after inoculation. Lung lesions consisted of thickened alveolar septa and neutrophil and macrophage infiltrates in the bronchioles and alveoli. Lung lesion scores in the SCID-bo mice inoculated with LKT(+)WT or LKT(-) mutant were significantly (P<0.05) greater than those of the PBS control group, but the two bacterial strains produced results that did not differ significantly. M. haemolytica was isolated from lung, liver and spleen after inoculation but less frequently as time progressed. In experiment B, SCID-bg mice were inoculated intratracheally with live LKT(+)WT or formalin-killed LKT(+)WT and killed 24, 48 or 96 h later. Lung lesions were histologically similar to those observed in experiment A; however, there were no significant differences in the lung lesion scores between groups. It was concluded that the lesions seen in this study were probably not due to LKT, and that the SCID-bo mouse does not provide a good rodent model for bovine pneumonia.

Animals↗

Normal-eye Zernike coefficients and root-mean-square wavefront errors.

PURPOSE: To compare aberrometry measurements from multiple sites and compute mean Zernike coefficients and root-mean-square (RMS) values for the entire data pool to serve as a reference set for normal, healthy adult eyes. SETTING: Northeastern State University, Tahlequah, Oklahoma, USA. METHODS: Data were collected from 10 laboratories that measured higher-order aberrations (HOAs) in normal, healthy adult eyes using Shack-Hartmann aberrometry (2560 eyes of 1433 subjects). Signed Zernike coefficients were scaled to pupil diameters of 6.0 mm, 5.0 mm, 4.0 mm, and 3.0 mm and corrected to a common wavelength of 550 nm. The mean signed and absolute Zernike coefficients across data sets were compared. Then, the following were computed: overall mean values for signed and absolute Zernike coefficients; polar Zernike magnitudes and RMS values for coma-like aberrations (Z(3)(+/-1) and Z(5)(+/-1) combined); spherical-like aberrations (Z(4)(0) and Z(6)(0) combined); and 3rd-, 4th-, 5th-, and 6th-order, and higher-order aberrations (orders 3 to 6). RESULTS: The different data sets showed good agreement for Zernike coefficients values across most higher-order modes, with greater variability for Z(4)(0) and Z(3)(-1). The most prominent modes and their mean absolute values (6.0-mm pupil) were, respectively, Z(3)(-1) and 0.14 microm, Z(4)(0) and 0.13 microm, and Z(3)(-3) and 0.11 microm. The mean total higher-order RMS was 0.33 microm. CONCLUSIONS: There was a general consensus for the magnitude of HOAs expected in normal adult human eyes. At least 90% of the sample had aberrations less than double the mean values reported here. These values can serve as a set of reference norms.

Adult↗

A review of horse-related injuries in a rural Colorado hospital: implications for outreach education.

INTRODUCTION: The literature contains many studies on the types of injuries sustained in horseback riding incidents. Most advocate the use of equestrian helmets to prevent head trauma. However, information is limited on other specific prevention strategies. METHODS: A 4-year, retrospective, and prospective review of medical records pertaining to horse-related injuries in a southwestern Colorado hospital yielded a sample of 85 patients who had been injured while riding or tending to horses. In addition to the record review, patients were interviewed during ED discharge, inpatient treatment, or in a follow-up telephone call to determine the types, causes, and mechanisms of injuries, and the circumstances surrounding the incidents. Operators of 7 guest ranches and outfitters within a 30-mile radius of the hospital plus 3 ranches in Oklahoma and an additional ranch in Colorado were contacted with the study results and suggestions for injury prevention. RESULTS: Patients ranged in age from 2 to 77 years. Fifty-five percent were inexperienced or beginner riders, 10% were novice riders, and 35% were experienced riders. Seventy percent were injured during recreational pursuits. The average Injury Severity Score for all patients was 8.5, with an average length of stay of 72 hours. Injuries were related to rider inexperience, equipment problems, or unpredictable horse behavior. CONCLUSION: Thirty-eight percent of the horse-related injuries were preventable. All operators of the guest ranches and outfitters were receptive to hearing or reading the study information. It is hoped that raising awareness and providing suggestions related to the screening of riders, prevention of injuries, and safety measures may decrease the numbers of horse-related injuries.

Adolescent↗

Radiofrequency treatment of turbinate hypertrophy: a randomized, blinded, placebo-controlled clinical trial.

OBJECTIVES: We sought to evaluate the short-term efficacy of radiofrequency volumetric tissue reduction (RFVTR) in treating nasal obstruction in subjects with inferior turbinate hypertrophy. STUDY DESIGN AND SETTING: We conducted a prospective, randomized, single-blinded, placebo-controlled trial with crossover option, involving 32 patients and performed in a clinical office setting at the University of Oklahoma Medical Center. RESULTS: The outcomes were measured using 10-cm visual analog scales (VASs) before treatment and at 8 weeks and 6 months posttreatment. Improvement was shown in frequency of obstruction, severity of obstruction, and overall ability to breathe for both the placebo and RFVTR treatment arms at 8 weeks (P < 0.05). The amount of improvement, however, was significantly better in the treatment arm compared with placebo for the severity of obstruction and overall ability-to-breathe categories. At 6 months, the mean improvement scores were significantly better than the pretreatment scores for all 3 categories. CONCLUSIONS: RFVTR is an effective alternative for the treatment of patients with nasal obstruction due to inferior turbinate hypertrophy. SIGNIFICANCE: This is the first randomized trial that demonstrates that RFVTR is significantly better than placebo in treating nasal obstruction due to inferior turbinate hypertrophy.

Adult↗

A longitudinal study of employment and skill acquisition among individuals with developmental disabilities.

Recent legislation, especially the Americans with Disabilities Act in 1990, generated the closure of institutions for people with disabilities and inclusion into community residences and employment. It has been well documented that individuals with developmental disabilities often experience difficulties with employment including both obtaining and maintaining jobs, and many researchers have looked for ways to make employment more successful [McConkey, R. & Mezza F. (2001). Employment aspirations of people with learning disabilities attending day centers. Journal of Learning Disabilities, 5(4), 309-318; Stevens, G. (2002). Employers' perceptions and practice in the employability of disabled people: a survey of companies in south east UK. Disability and Society, 17(7), 779-796; Capella, M., Roessler, R., & Hemmeria, K. (2002). Work-related skills awareness in high-school students with disabilities. Journal of Applied Rehabilitation Counseling, 33(2), 17-23; Ingraham, K., Rahimi, M., Tsang, H., Chan, F., & Oulvey, E. (2001). Work support groups in state vocational rehabilitation agency settings: a case study. Psychiatric Rehabilitation Skills, 5(1), 6-21; Gosling, V. & Cotterill, L. (2000). An employment project as a route to social inclusion for people with learning difficulties? Disability and Society, 15(7), 1001-1018; Neitupski, J. & Hamre-Nietupski, S. (2000). A systematic process for carving supported employment positions for people with severe disabilities. Journal of Developmental and Physical Disabilities, 12(2), 103-119]. While research has accumulated that has examined predictors of successful employment, this research assessed longitudinal outcomes of employment. Data were obtained from an existing data set of all known persons receiving services from the Developmental Disabilities Division of the Oklahoma Department of Human Services (N=2760). Results indicated that as people moved to employment, scores on adaptive skills increased, that as people moved from employment, adaptive skills decreased, and that as employment status remained constant, adaptive skills also remained unchanged. No consistent impact was found on challenging behaviors. Type of employment (sheltered, supported, and competitive) was then examined, and the same pattern of changes in adaptive skills was found; i.e., changes in employment to more/less competitive was accompanied by more/less adaptive skills. This suggests that employment itself, especially work in the competitive workforce, may be a significant source of enhancing adaptive skills for people with developmental disabilities and, thus, greatly adding to the success of community living.

Adult↗

Obtaining sensitive information from a wary population: a comparison of telephone and face-to-face surveys of welfare recipients in the United States.

Recent studies reveal the benefits of technological developments such as audio computer assisted self-interviewing (A-CASI) in interview methodology, especially for surveys of sensitive behavior and information. However, we believe that the selection of mode of administration depends not only on the technology available and the behavior of interest, but also on the specific population under study. We therefore assess survey mode effects on reported rates of alcohol and drug use among welfare recipients, an especially important group for scholars and public health agencies. The sample consisted of adult recipients of Temporary Assistance to Needy Families (TANF) in Oklahoma, January 2001. Adjusting for demographic characteristics, employment, and education, we employ odds ratios to compare 30-day, 1 year, and lifetime prevalence estimates from telephone and face-to-face surveys. Telephone methodology yields similar or higher estimates for lifetime prevalence of alcohol, marijuana, and hard drug use and abuse, though lower estimates of recent use. We discuss our findings in relation to underfunded public health agencies that must efficiently assess and respond to local levels of drug abuse and we conclude that mode selection may depend upon the population under study.

Adolescent↗

Bovine viral diarrhoea virus (BVDV) subgenotypes in diagnostic laboratory accessions: distribution of BVDV1a, 1b, and 2a subgenotypes.

The prevalence of bovine viral diarrhoea virus (BVDV) biotypes and subgenotypes was determined from 131 BVDV positive samples from a diagnostic laboratory. The majority of the isolates were from Oklahoma; however, other states including Kansas, Texas, and Arkansas were represented. These BVDV samples were from submissions of 76 live animals and 55 necropsy samples. There were 131 BVDV samples represented by 117 noncytopathic (NCP), 11 cytopathic (CP) and 3 cases with mixed NCP and CP biotypes. The NCP isolates were more common (P < 0.05) than the CP and NCP/CP combination. The BVDV samples were segregated into three subgenotypes by differential PCR and sequencing of a viral genomic region, 5'-untranslated region (5'-UTR). There were more BVDV1b subgenotypes 60/131 (45.8%) than BVDV1a, 37/131 (28.2%) or BVDV2a, 34/131 (26.0%) (P < 0.05). The organ system involvement included the major categories such as respiratory, digestive, mixed/multiple organs, abortions, and persistent infections (PI). All three BVDV subgenotypes were found in persistently infected (PI) cattle and respiratory diseases, both major requests for BVDV diagnosis. Only one of the 131 viruses was genetically similar to the strains present in U.S. vaccines.

Animals↗

Clinical field efficacy and safety of pyrantel pamoate paste (19.13% w/w pyrantel base) against Anoplocephala spp. in naturally infected horses.

Clinical field trials were conducted at five geographical locations in the USA (Oklahoma, Wisconsin, Tennessee, Virginia and Idaho) to evaluate the efficacy and safety of pyrantel pamoate paste (19.13%, w/w, pyrantel base) administered at the recommended dosage of 13.2 mg pyrantel base/kg (6.0 mg pyrantel base/lb) body weight (b.w.) against tapeworm infections of Anoplocephala spp. in naturally infected horses. Horses at each study site were allocated by restricted randomization based on the cestode status (positive or negative) of pre-treatment fecal egg counts to complete sets of four animals each or incomplete sets of fewer than four animals. Within sets comprising of two to four horses, one animal was randomly allocated to receive placebo vehicle paste and the remaining horse(s) received pyrantel pamoate paste administered orally at a minimum dosage of 13.2 mg pyrantel base/kg b.w. on Test Day (TD) 0. Single animal sets received pyrantel pamoate paste. Fecal samples of horses were collected and examined for equine tapeworm (Anoplocephala spp.) eggs a minimum of four times (once or thrice between TD -28 and -14, twice between TD -14 and -7, and once on TD 0) prior to treatment on TD 0. Fecal samples of horses that were positive for cestode infection pre-treatment were examined for cestode eggs on TD 7, 8, 9, 14, 15 and 16. Cestode-negative pre-treatment horses were not sampled again after treatment. A total of 241 horses (141 mares, 16 stallions and 84 geldings; 6 months-30 yrs of age; 173-646 kg; 13 recognized breeds and various crossbreds) were evaluated. The prevalence of Anoplocephala spp. determined by pre-treatment fecal examination ranged from 38.3% in Idaho to 68.1% in Tennessee with an overall prevalence of 52.3%. Ninety cestode-positive and 88 cestode-negative horses were treated with pyrantel pamoate paste, 36 cestode-positive and 27 cestode-negative horses were treated with placebo vehicle paste. Overall, 178 horses were treated with pyrantel pamoate paste, and 63 horses were treated with placebo paste. Of the 178 horses treated with pyrantel pamoate paste, no drug related, adverse clinical or neurological health events were observed. No doses of pyrantel pamoate paste were refused or lost during dosing. At each post-treatment time sampling interval, significantly fewer cestode eggs (P < 0.0115) were passed by cestode-positive horses treated with pyrantel pamoate paste compared to cestode-positive horses that received placebo paste. Efficacy of the pyrantel pamoate paste treatment ranged from 92 to 96% from TD 7 to TD 16 with an overall efficacy of 95%. The results of these trials demonstrated that pyrantel pamoate paste (19.13%, w/w, pyrantel base) administered orally at a dosage of 13.2 mg pyrantel base/kg b.w. is highly efficacious (95%) against Anoplocephala spp. and safe for use in horses with no adverse clinical or neurological health events observed under field use conditions.

Administration, Oral↗

Preoperative predictors of positive margins after loop electrosurgical excisional procedure-Cone.

OBJECTIVE: A LEEP-Cone may not be necessary for all patients with traditional cone indications. This study defines populations where a single pass technique with the LEEP is appropriate. METHODS: We retrospectively reviewed patients undergoing LEEP-Cone procedures performed at the University of Oklahoma Health Science Center from February of 1994 to July of 2002. Patients include those for LEEP-Cone with traditional excisional indications and those who underwent LEEP-Cone at the operating physician's discretion. Statistical analysis was used to compare preoperative factors with the resultant pathologic results. RESULTS: A total of 248 women underwent LEEP-Cone. 50.0% (33/66) of the patients with positive margins on the first pass had dysplasia or worse (CIN I-III or CA) in the second pass (top hat), compared to 6.6% (12/182) of the patients with a negative first pass (P < 0.0001). Univariate analysis found CIN III on histology and parity to be predictive of dysplasia in the top hat and two-step discrepancy to predict absence of dysplasia. On multivariate analysis, two-step discrepancy and parity remained predictive. Age >35 was the greatest percentile predictor of dysplasia in the top hat, and 91.5% of women <21 had normal top hat pathology. CONCLUSION: The retrospective data reported regarding LEEP-Cones reveal increased parity to predict dysplasia in the top hat and two-step discrepancy as a poor predictor of dysplasia in the top hat. Women under 21 years of age should have a single pass LEEP technique. The "top hat" is more appropriate as parity and age increase.

Adult↗

Designing services for the elderly.

Even after careful planning and a successful launch, even the best geriatric care program can not always expect smooth sailing, according to industry executives. Allen Mathies, president and chief executive officer at Huntington Memorial Hospital, cited a paradoxical side effect stemming from the success of his hospital's geriatric outreach programs. "On the one hand, by moving patients through a continuum of outpatients services, our program has helped to reduce the extraordinary costs associated with acute care hospitalization," he said. "On the other hand, those patients who are hospitalized tend to be more acutely ill. They use tremendous resources, but at a fixed reimbursement. There is a lack of recognition of our real costs by the payer." Why, then, do Huntington Memorial Hospital, Baptist Medical Center of Oklahoma, Morton F. Plant Hospital, Northwestern Memorial Hospital and other hospitals intend to continue their efforts on behalf of their communities' aging populations? The answer is that, reimbursement problems notwithstanding, benefits can be derived from making a commitment to geriatric care. "We have 19,000 people enrolled in our elder care program," Hupfeld said. "That's a powerful force. They vote. They lobby on our behalf. They support the hospital philanthropically. If you do a good job of reaching the older adults in your community, you'll find they are a powerful marketing force. They can do a lot for your image when it comes to reaching other market segments."

Aged↗

Prevalence and correlates of mitral regurgitation in a population-based sample (the Strong Heart Study).

Evidence suggesting that mitral regurgitation (MR) may be induced by appetite suppressant medications heightens the importance of understanding the prevalence and correlates of MR, especially its relation to obesity, in population-based samples. MR was assessed by color Doppler echocardiography in 3,486 American Indian participants in the Strong Heart Study. Mild (1+) MR was present in 19.2%, moderate (2+) MR in 1.6%, moderately severe (3+) in 0.3%, and severe (4+) in 0.2% of participants. In univariate analyses, MR was unrelated to gender, diabetes, or lipid levels, but was more frequent in North/South Dakota (28.3%) than in Oklahoma (21.6%) or Arizona (14.3%) (p <0.001). MR was related to lower body mass index (BMI) (p <0.001), older age (p <0.001), higher systolic blood pressure (p = 0.003), higher serum creatinine (p <0.001), and higher urine albumin/creatinine ratio (p <0.001). In multivariate analyses, the presence and severity of MR were independently associated with higher serum creatinine, lower BMI, mitral stenosis, prior myocardial infarction, female gender, mitral valve prolapse and, variably, older age. In conclusion, MR, mostly mild, is detected by color Doppler echocardiography in >20% of middle-aged and older adults. MR is independently associated with female gender, lower BMI, older age, and renal dysfunction, as well as with prior myocardial infarction, mitral stenosis, and mitral valve prolapse. It is not related to dyslipidemia or diabetes.

Aged↗

Major electrocardiographic abnormalities among American Indians aged 45 to 74 years (the Strong Heart Study).

As part of the Strong Heart Study assessment of prevalent cardiovascular disease in middle-aged to elderly American Indians, the prevalence of major Minnesota code electrocardiographic (ECG) abnormalities was assessed in 4,531 participants aged 45 to 74 years (59% women) in selected tribal communities in Arizona, South and North Dakota, and Oklahoma. The overall prevalence of major ECG abnormalities was lowest in Arizona participants, (e.g., definite ECG myocardial infarction in 0.3% vs 1.8% in the other centers), although nearly two thirds of them had diabetes. One or more major ECG abnormality occurred in progressively more women (10.4% to 21.2%) and men (13.3% to 32%) (both p < 0.0001) from 45- to 54- to 55- to 64- and 65- to 74-year age groups, with the latter prevalence rates exceeding those in predominately white age peers in the Cardiovascular Health Study. Diabetes in women, but not in men, and hypertension in both genders showed positive associations with prevalence rates of major ECG abnormalities compatible with coronary artery disease or hypertensive cardiac hypertrophy. Hypercholesterolemia was not associated with ECG abnormalities except for definite myocardial infarction in women. In conclusion, major ECG abnormalities are common in middle-aged to elderly American Indians ,consistent with recent documentation of higher cardiovascular mortality in this population than in similar aged U.S. whites.

Adult↗

The Ross operation: a 12-year experience.

BACKGROUND: The Ross operation, originally introduced as a scalloped subcoronary implant with an 80% survival and 85% freedom from reoperation, has recently been modified to a root replacement which is now the most utilized implant technique. The mid and late results of this operative technique and comparison of intra-aortic implants and root replacement in a single institution are reported. METHODS: The records of 328 patients who had a Ross operation at the University of Oklahoma (August 1986 to July 1998) were reviewed to assess operative technique and patient-related factors on survival, autograft valve function, homograft valve function, valve-related complications, and need for reoperation. RESULTS: Operative survival was 95.4% with an actuarial survival of 89% +/- 5% at 8 years. Freedom from replacement of the pulmonary autograft was 94% +/- 3% at 8 years, freedom from reoperation on the pulmonary homograft was 90% +/- 4% at 8 years, and freedom from autograft valve reoperation or dysfunction (3+ autograft valve insufficiency) was 83% +/- 6% at 9 years. The incidence of autograft valve reoperation and late autograft valve dysfunction was decreased by root replacement. Annulus reduction and fixation improved early results in patients with aortic insufficiency and annulus dilatation. CONCLUSIONS: Early results have been excellent, as the development of late autograft valve dysfunction or dilatation has been rare. The excellent hemodynamic results with a limited incidence of reoperation and replacement of the autograft valve justify its continued use.

Actuarial Analysis↗

Geographic variations, cloning, and functional analyses of the venom acidic phospholipases A2 of Crotalus viridis viridis.

Geographic venom samples of Crotalus viridis viridis were obtained from South Dakota, Wyoming, Colorado, Oklahoma, Texas, New Mexico, and Arizona. From these samples, the phospholipases A(2) (PLA(2)s) were purified and their N-terminal sequences, precise masses, and in vitro enzymatic activities were determined. We purified two to four distinct acidic PLA(2)s from each sample; some of them displayed different inhibition specificities toward mammalian platelets. One of the acidic PLA(2)s induced edema, but had no anti-platelet activity. There was also a common basic PLA(2) myotoxin in all the samples. We have cloned five acidic PLA(2)s and several hybrid-like nonexpressing PLA(2)s. Molecular masses and N-terminal sequences of the purified PLA(2)s were matched with those deduced from the cDNA sequences, and the complete amino acid sequences of five novel acidic PLA(2)s were thus solved. They share 78% or greater sequence identity, and a cladogram based on the sequences of many venom acidic PLA(2)s of New World pit vipers revealed at least two subtypes. The results contribute to a better understanding of the ecogenetic adaptation of rattlesnakes and the structure-activity relationships and evolution of the acidic PLA(2)s in pit viper venom.

Amino Acid Sequence↗