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Biomedical subjects

K A Murphy

Publications and source records attributed to K A Murphy.

14 recordsLinked to original sources
PubMed2005

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces matrix metalloproteinase (MMP) expression and invasion in A2058 melanoma cells.

There has been a 34% increase in melanoma related mortality in the United States from 1973 to 1992. Although few successful treatments for malignant melanoma exist, it is known that genetic susceptibility and environmental factors contribute to the initiation and progression of melanoma. Excessive UV exposure is considered the main etiological factor in melanoma initiation, however, epidemiological and experimental evidence suggests that exposure to environmental carcinogens contribute to melanoma. We propose that exposure to environmental chemicals that activate the aryl hydrocarbon receptor pathway contribute to melanoma progression, specifically through stimulation of the expression and activity of the matrix metalloproteinases (MMPs). Therefore, we investigated the effect of AhR activation on normal human melanocytes and several melanoma cell lines. The data presented here demonstrate that normal melanocytes and melanoma cells express the AhR and Arnt and are responsive to activation by TCDD. Furthermore, activation of this pathway in transformed melanoma cells (A2058) results in increased expression and activity of MMP-1, MMP-2 and MMP-9, as well as increased invasion using in vitro invasion assays. Furthermore, TCDD-induced expression of the MMP-1 promoter in melanoma cells appears to require different elements than those required in untransformed cells, indicating that this pathway may have multiple mechanisms for activation of MMP expression.

Aryl Hydrocarbon Hydroxylases↗
PubMed2000

Validity of residents' self-reported cardiovascular disease prevention activities: the Preventive Medicine Attitudes and Activities Questionnaire.

BACKGROUND: This article describes the development, reliability, and validity of three cardiovascular disease (CVD) prevention subscales-CVD prevention behaviors, perceived importance, and perceived effectiveness-of the Preventive Medicine Attitudes and Activities Questionnaire (PMAAQ). METHODS: The PMAAQ was administered three times to University of Minnesota family practice residents (178) over 2 years (91% response rate). Stability measures were calculated, and validity was demonstrated in four ways: content validity through an expert panel; calculation of internal consistency reliabilities; demonstration of divergent validity; and external validation via a separate chart review. RESULTS: High internal consistency reliabilities among the subscales were seen (Cronbach's alpha = 0.77 to 0.92). Divergent validity was verified by low intercorrelations among the subscales (r = -0.23 to 0.27). Two-month test-retest scores ranged from Cronbach's alpha = 0.47 to 0.64. Significant correlations were seen between the chart review scale and both the CVD behaviors subscale and the PMAAQ smoking scale (r = 0.25 and 0.36, respectively). CONCLUSIONS: Results indicate that the PMAAQ can validly and reliably measure residents' CVD prevention behaviors and provide insight into their preventive health care attitudes. Further, the independence among the subscales suggests that importance and effectiveness by themselves do not affect behavior and that other factors are likely to be important in influencing physician behavior change.

Adult↗
PubMed1999

A prehistoric example of polydactyly from the Iron Age site of Simbusenga, Zambia.

Human burials, dated AD 1100-1500, were examined from the Iron Age site of Simbusenga, located some 35 miles northwest of Victoria Falls in Zambia. Pedal polydactyly was discovered in the fragmentary remains of a young adult of indeterminate sex aged 14-25. The preaxial form of polydactyly is indicated with bilateral involvement of the first metatarsals. There is incomplete hypoplastic duplication of both first metatarsals with broad heads for the metatarsal-phalangeal joints. No digital malformations were found in the other seven individuals with feet and/or hands from the site. Several studies point to autosomal dominance for cases of isolated polydactyly, but inheritance and patterning of preaxial polydactyly are still incompletely understood. The condition is also found in conjunction with genetic malformation syndromes such as Acrocephalypolysyndactyly, Lambotte, Oro-facio-digital, and VATER. High frequencies of polydactyly are reported for African and African-American populations, but further analysis reveals that the bulk of previously reported cases of polydactyly are representative of the postaxial form as opposed to the preaxial expression seen here.

Adolescent↗
PubMed1998

Social work assessment at end of life: practice guidelines for suicide and the terminally ill.

As social workers, we are educated about the values of client self-determination as well as the affirmation of uniqueness in how the client experiences life and death. In terms of choices at the end of life, assisted suicide has begun to come out of the closet, so to speak, and as a result, the National Association of Social Worker's adopted a policy in 1993 which addresses this end of life option. Oregon passed Ballot Measure 16 in November of 1994 which allows for a terminally ill person to request drugs to end life. As the legalities of assisted suicide are decided by judges and courts, some terminally ill people will think about and decide to take their own lives rather than wait for the disease process to come to its own ending. There are very few practice guidelines available to social workers who work with the suicidal terminally ill. A traditional mental health model for evaluation of lethality cannot be imposed onto this population. A three-part model for assessment and evaluation of a suicidal request from a terminally ill person is proposed in this article.

Attitude to Death↗
PubMed1996

Ventricular outflow tract reconstructions with cryopreserved cardiac valve homografts. A single surgeon's 10-year experience.

OBJECTIVE: From January 1, 1985 through December 31, 1994, one surgeon implanted cryopreserved valved homografts into 149 patients--65 since December 1988. This latter series (II) was accomplished in a single hospital, facilitating patient follow-up with biannual echocardiograms. Analysis of these 65 patients is the primary focus of this report; the indications and early surgical results for the two parts of the series (I and II) are compared to assess the evolution of a single surgeon's use of homografts in a mixed pediatric and adult practice. METHODS: Fifty-one variables for each patient (series II) were entered into a computerized database and analyzed (multivariate and univariate) using SPSS 6.1 software (Statistical Products and Service Solutions, Chicago, IL). Cox proportional hazard model was used to identify the independent contribution of each variable for patient mortality and homograft failure. Cumulative survival estimates were made using Kaplan-Meier analysis. Homograft failure was defined as requirement for replacement or death. In series I, there were 41 left ventricular outflow tract (LVOT) reconstructions (31 adult) and 43 right ventricular outflow tract (RVOT) reconstructions (42 pediatric). In series II, there were 55 RVOT reconstructions (52 pediatric) and 10 LVOT reconstructions (7 adult). RESULTS: There were no technical surgical failures. Total surgical mortality rate was 6% (5/84) in series I (3 LVOT, 2 RVOT) and 15% (10/65) in series II (2 LVOT, 8 RVOT) (I vs. II NS; p = 0.11, two-tailed Fisher exact test). By the Cox analysis, only age < 2 years (p < 0.03) and cross-clamp time > 120 minutes (p < 0.05) were significant predictors for death. Age-based survival curves were compared in a sequential bivariate analyses (log rank test) and age < 2 years again was a significant predictor of decreased patient survival (p < 0.006). Actuarial freedom from patient death or reoperation for homograft failure was 82% +/- 7% at 1000 days and 77% +/- 10% at 2000 days. Three patients required re-replacement for homograft failure (5.4%); one of these patients died. The only significant predictor of homograft failure was postoperative endocarditis (p < 0.05). Homograft performance was evaluated by an extensive echocardiography protocol: in surviving patients and homografts, three valved conduits were judged to have severely impaired performance (stenosis or regurgitation), awaiting surgical replacement for a putative total homograft-related structural failures rate of 11% at 5 1/2 years. CONCLUSIONS: Comparisons of series I and II shows, in one surgeon's practice, an evolution away from use of cryopreserved homografts for LVOT reconstructions except when needed for destructive bacterial endocarditis or complex congenital anatomy. Homograft efficacy and durability were similar in RVOT and LVOT positions, with 78.5% of patients surviving at 5 1/2 years; in surviving patients, 89% of homografts have continued to function well. Homografts are not immune to prosthetic bacterial endocarditis, and its occurrence is associated with accelerated deterioration. Cryopreserved homograft valves are an imperfect but satisfactory biological material for specific ventricular outflow reconstructions.

Adolescent↗
PubMed1994

Inverse techniques in hyperthermia: a sensitivity study.

Numerical modeling methods and hyperthermia treatment temperature measurements have been used together to reconstruct steady-state tumor temperature distributions. However, model errors will exist which may in turn produce errors in the reconstructed temperature distributions. A series of computer experiments was conducted to study the sensitivity of reconstructed two-dimensional temperature distributions to perfusion distribution modeling errors. Temperature distributions were simulated using a finite element approximation of Pennes' bioheat transfer equation. Relevant variables such as tumor shape, perfusion distribution, and power deposition were modeled. An optimization method and the temperatures "measured" from the simulated temperature distributions were used to reconstruct the tumor temperature distribution. Using this procedure, the sensitivity of the reconstructed tumor temperature distribution to model-related errors, such as the perfusion function, was studied. It was found that: 1) if the problem is conduction dominated, large errors in the perfusion distribution produce only small errors in the reconstructed temperature distribution (maximum error < 1.0 degrees C), and 2) when the actual perfusion distribution contains a small random variation (+/- 15%) which is neglected by the model, the reconstructed temperature distribution will be in good agreement with the actual temperature distribution (maximum error < or = 0.3 degrees.

Algorithms↗
PubMed1993

Ophthalmic contact lens with internal fixation light for examination of the optic nerve head.

Stereoscopic slitlamp examination of the optic nerve head in one-eyed patients is difficult because there is currently no way to provide the patient with a fixation target. This situation is often aggravated in glaucoma patients by a miotic and fixed pupil. We have developed a funduscopic contact lens which incorporates a fixation target, allowing the patient to view the target with the eye being examined. The device has been successfully tested on normal volunteers.

Contact Lenses↗
PubMed1988

Caffeine poisoning treated by hemoperfusion.

A case of acute caffeine poisoning with resultant ventricular fibrillation and coma was treated by emergency hemoperfusion. Clinical symptomatology improved dramatically with resolution of arrhythmias and return to normal consciousness over a five-hour period.

Adult↗
PubMed1984

Prediction of chronicity in acute low back pain.

Forty-eight patients seeking treatment for low back pain were assessed in the acute stage to see if they exhibited characteristics that would predict response to medical treatment. It was hoped that, if there were personality and demographic differences between patients who did and those who did not respond to standard medical treatment, potential chronic pain patients could be identified and targeted for special treatment. Stepwise discriminant analysis yielded a prediction equation that correctly identified 41 of the 48 cases (85.4%). Acute patients who became chronic complained of pain over a wider area of the body; had deeper, more central pain; were highly anxious; and had a lower activity level. Although cross-validation studies are needed, identification of potentially chronic pain patients may be feasible, making appropriate early intervention possible.

Back Pain↗
PubMed1982

An improved micromethod for evaluating the phagocytic potential of granulocytes by the nitroblue tetrazolium (NBT) slide test.

A comparison of granulocyte preparations obtained with the original endotoxin-stimulated nitroblue tetrazolium (NBT) slide test and a modified NBT slide test developed in our laboratory was performed as blind study on paired peripheral blood samples from 25 normal, adult humans and 25 normal, adult BALB/c mice. Distinct qualitative differences between granulocyte preparations obtained with the two NBT methods were observed. The original NBT procedure yielded cell preparations which were poorly stained and morphologically altered. In contrast the modified procedure consistently resulted in human and murine cell preparations which were intensely stained and morphologically intact. A blinded comparison of the number of NBT-positive cells showed quantitative differences between the original and modified NBT slide tests. The average percentage of NBT-positive cells of the 25 normal human subjects was 79.81 +/- 17.40 with the original method and 90.83 +/- 7.71 with the modified method (p less than 0.0002). The average percentage of NBT-positive cells obtained on 25 normal BALB/c mice was 29.52 +/- 17.26 and 69.22 +/- 9.01 for the original and modified procedures, respectively (p less than 0.0001). The increased numbers of NBT-positive cells observed with the modified NBT procedure may have resulted from variation in the original method due to the misinterpretation of weakly stained and morphologically altered granulocyte preparations.

Adult↗
PubMed1981

Saturday night fever: a common-source outbreak of rubella among adults in Hawaii.

During the summer of 1977, an epidemic of rubella occurred among adults in Hawaii. The highest attack rate was in women 20-24 years old (226/100,000), with almost total sparing of young schoolchildren. A case-control investigation implicated a specific discotheque as a common place of exposure for persons with onset of disease during the epidemic peak (chi 2 = 12.9,p less than 0.001). A piano player/singer at the discotheque was the apparent source of the virus transmission. The large number of cases linked to this musician suggests that airborne transmission occurred while he was singing rather than by direct person-to-person contact. Rubella vaccine was given to 6523 women in public clinics held during the epidemic. Despite screening for pregnancy and birth control usage, 23 women (3.5/1000) became pregnant within three months after receiving the vaccine. Eleven of 12 women who reportedly contracted natural rubella while pregnant elected to terminate their pregnancies; the 12th had a normal appearing infant. The susceptibility rate for all adults tested for rubella hemagglutination inhibition antibody was 36.9%, a rate similar to the found in earlier surveys in Hawaii. The occurrence of this epidemic confirms the changing epidemiology of rubella with respect to age distribution and supports the view that vaccination of young children may not be sufficient to protect adult women from exposure to rubella, especially in areas where a high proportion of adults remain susceptible.

Adolescent↗
PubMedDate not supplied

Acetaminophen and ibuprofen: fever control and overdose.

Fever has been recognized as a sign of disease for centuries. Health care professionals and parents frequently search for new methods of pediatric fever control. Current research suggests that prostaglandins play an important role in fever production. As antipyretics, both acetaminophen and ibuprofen are effective in fever reduction by inhibiting prostaglandin synthesis. In this article, the pathophysiology of fever is discussed as a foundation for understanding fever management. The metabolic pathways of both agents are compared as they relate to fever control; the common side effects and nursing management for acute overdoses are discussed.

Acetaminophen↗