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Biomedical subjects

J Burnham

Publications and source records attributed to J Burnham.

12 recordsLinked to original sources
PubMed2001

Age and TP53 mutation frequency in childhood malignant gliomas: results in a multi-institutional cohort.

Malignant astrocytoma is one of the most deadly primary central nervous system tumors. Although significant progress has been made in understanding the molecular pathways that lead to the development of these tumors in adults, comparatively little analysis has been done in childhood astrocytomas, which are less common and have a more favorable prognosis. Our previous studies of an institutional cohort of children with malignant gliomas suggested the existence of distinct molecular pathways of tumorigenesis in younger versus older children, based on the finding of a high frequency of TP53 mutations in tumors from children >3 years of age at diagnosis, compared with those from younger children. In the current study, the association between TP53 mutations and age was examined in greater detail using the multi-institutional group of children enrolled in Children's Cancer Group Study 945, the largest cohort of childhood high-grade gliomas analyzed to date. Seventy-seven tumors with centrally reviewed diagnoses of anaplastic astrocytoma or glioblastoma multiforme had sufficient archival histopathological material for microdissection-based genotyping. Sections were examined histologically, and topographic targets that contained malignant tissue were isolated by microdissection and subjected to PCR-based amplification and sequencing of TP53 exons 5-8. Twenty-six tumors (33.8%) had mutations in those exons. Mutations were observed in 2 of 17 tumors (11.8%) from children <3 years of age at diagnosis versus 24 of 60 tumors (40%) from older children, a difference that was statistically significant (P = 0.04), in agreement with our previous results. Whereas malignant gliomas in older children have a frequency of mutations comparable to tumors that arise in young adults, those from children <3 years old do not. The association between age and frequency of TP53 mutations among pediatric malignant gliomas indicates the probable existence of two distinct pathways of molecular tumorigenesis in younger versus older children.

Adolescent↗
PubMed1994

Development and validation of a scale for rating mood states of psychiatric inpatients.

OBJECTIVE: The authors assessed reliability and validity of a scale developed for use with inpatients on a mood disorders unit. The scale is used to rate a patient's mood along a quantitative continuum from -5, depressive stupor, through 0, euthymic, to 5, full mania. The scale lists behaviors that constitute criteria for each rating point. Mixed states and idiosyncratic behavior can also be assessed. METHODS: Assessment of the scale's reliability and validity was based on data for 53 psychiatric inpatients. The scale's reliability was assessed by comparing nurses' ratings. Validity was assessed by comparing nurses' ratings with patients' self-ratings using previously validated self-report instruments as well as a patient self-report version of the scale. RESULTS: Interrater reliability for the instrument was high (r = .84). Estimates of validity obtained using patient self-report measures ranged from .54 to .85. CONCLUSIONS: The psychometric properties of the scale are comparable to and in some cases are superior to those reported for instruments that include more items and that take longer to complete.

Adult↗
PubMed1993

Comparison of CINAHL, EMBASE, and MEDLINE databases for the nurse researcher.

The purpose of this research was to determine which of three databases, CINAHL, EMBASE or MEDLINE, should be accessed when researching nursing topics. The three databases were searched for citations on topics selected by three nurse researchers and the results were compared. For the search of nursing care literature on a medical condition, it was helpful to search both CINAHL and MEDLINE. CINAHL provided the majority of relevant articles for the second search, on computers and privacy, but inclusion of MEDLINE and EMBASE enhanced retrieval somewhat. The search on substance abuse in pregnancy, not restricted to nursing literature, retrieved better results when searching both MEDLINE and EMBASE. Due to the nature and distribution of the nursing literature, it is especially important for the searcher to understand and respond to the focus of the researcher.

Clinical Nursing Research↗
PubMed1987

Trichinella spiralis: behavior, structure, and biochemistry of larvae following exposure to components of the host enteric environment.

Four layers are present on the surface of infective larvae of Trichinella spiralis isolated from host muscle in pepsin-HCl. Trypsin treatment of pepsin-HCl isolated worms caused partial degradation and removal of large patches of the two outer surface layers. Following exposure to bile, only traces of the outer layers remained on the worms surface. These changes in the worm surface were accompanied by a shift from Type I behavior, typical of pepsin-HCl isolated larvae, to Type II behavior, (snakelike) following exposure to either trypsin or bile. Worm behavior was also temperature dependent. Type I behavior was typical of worms maintained at room temperature regardless of treatment, while Type II behavior displayed by worms held at 37 C was treatment dependent. The absorption of in vitro glucose or beta-methyl-D-glucoside was lowest in pepsin-HCl isolated first stage infective larvae, significantly higher in trypsin treated worms and greatest in worms following exposure to bile. Sugar uptake by worms isolated from the host small intestine after 1 hr of enteral infection was similar to that seen in worms isolated from host muscle in pepsin-HCl. Sugar uptake in vitro in worms 2 hr following enteral infection was similar to worms following exposure to bile. The highest levels of sugar absorption in vitro occurred in worms which had resided in the small intestine for 3 hr. The lowest rates of incorporation of label into worm tissues was seen in 1 hr enteral and pepsin-HCl isolated worms. Infective larvae treated with trypsin or bile incorporated significantly greater amounts of label than the two former groups. The highest levels of incorporation of label into worm tissues was seen in 3 hr enteral worms. These findings support the view that trypsin, bile, and temperature serve as environmental cues which lead to alteration of the parasite's behavioral and nutritional status.

Absorption↗
PubMed1986

Recurrent hepatitis B in liver allograft recipients. Differentiation between viral hepatitis B and rejection.

The histologic findings in the original liver obtained from 9 liver allograft patients with active B virus hepatitis were compared with 28 posttransplant pathology specimens. All specimens were studied with the use of light and immunohistochemical microscopy in conjunction with pertinent clinical data. Eight of the 9 patients had chronic active hepatitis B (HB) with cirrhosis, prior to transplant, one of which had coexistent hepatocellular carcinoma. The ninth patient had fulminant hepatic necrosis secondary to acute HB prior to transplantation. In all of the patients with chronic HB prior to transplantation who survived more than 2 months after transplantation recurrent infection of the graft developed despite perioperative HB immunoglobulin therapy. The patient with acute fulminant hepatitis B pretransplant has done well postoperatively and has evidence of HB virus immunity (positive anti-HBs) 15 months after transplantation. Examination of tissue specimens obtained during episodes of allograft dysfunction in these 9 patients indicate that pathologic alterations of active HB infection of the allograft are associated with a preferential lobular insult, whereas those occurring in rejection preferentially involve portal tract structures. Serologic data combined with biopsy histopathologic data are essential in distinguishing between the two quite different events.

Diagnosis, Differential↗
PubMed1985

Case study: developing product lines using ICD-9-CM codes.

In this marketing case study, Thomas Jefferson University Hospital used a product line approach to maximize the use of its resources. The method used, based on ICD-9-CM codes, fulfilled the demands of increased efficiency by encouraging customer-oriented thinking, enhancing communication with physicians and patients, and helping the institution to compete more effectively.

Diagnosis-Related Groups↗
PubMed1978

Squirrel monkey temporary threshold shift from 48-h exposures to low-frequency noise.

Five squirrel monkeys were exposed for 1, 2, 4, 8, 16, 24, and 48 h to a 375--750-Hz band noise at an overall SPL of 95 dB. The TTS4.5 growth pattern for the 750-Hz test frequency was biphasic and did not reach an asymptote after 48 h of exposure. For all exposures, the mean thresholds of the five monkeys returned to within 5 dB of the preexposure mean 20 h after exposure. Recovery curves from all exposures at the 750-Hz test frequency appeared biphasic. Increasing SPL from 95 to 105 dB increased TTS4.5 by 4 dB at 750 Hz for a 1-h exposure. Recovery from the 105-dB exposure followed the same pattern as recovery from the 95-DB exposure. When compared with data collected from human subjects under similar conditions, these experiments indicate that the growth and recovery of TTS in squirrel monkeys are sufficiently similar to growth and recovery in man to justify further comparative investigation.

Animals↗
PubMedDate not supplied

Medical information on the Internet.

Connecting to the Internet allows health care professionals to access medical information at computer sites worldwide, to search databases, communicate with peers, obtain continuing education, retrieve images and software, obtain drug information and access statistical data. Users can access sites with "virtual patients," search library catalogs, locate jobs and post resumes, and explore conference sites and topics. Rural health care professionals can have access to medical information equivalent to their urban peers. Information is usually available over the Internet much more rapidly than through traditional print methods.

Computer Communication Networks↗