CONCLUSIONS: This collaborative study, conducted by members of the Cancer Information Service Research Consortium Team for Evaluation and Audit Methods and the Network Analysis Advisory Board, is part of a larger project that evaluates the impact of communication structure on innovation within the contractual network of the Cancer Information Service (CIS). This study examines four different technological innovations with respect to the characteristics of relative advantage, compatibility, observability, complexity, trialability, adaptability, riskiness, disadvantage, computer knowledge, and acceptance. METHODS: Data were gathered from self-report questionnaires completed in May 1995 by organizational members (n = 82) within the National Cancer Institute's CIS, a geographically dispersed federal government health information program. RESULTS: Paired comparison t tests found that organizational members rate contrasting dimensions of an innovation differentially, depending on the nature of the specific technology. For example, significantly lower levels of riskiness were reported for computerization for communication (e.g., e-mail) than for computerization for telephone service or outreach. In addition, computerization for office management had significantly lower levels of riskiness than computerization for telephone service or outreach. With respect to complexity, computerization for communication had significantly lower ratings than did outreach. In terms of observability and trialability, computerization for communication had significantly lower ratings than for telephone service. With respect to relative advantage, computerization for office management had significantly lower ratings than all other areas of computerization. In terms of computer knowledge, ratings were significantly higher for communication than for all other areas of computerization. No significant differences were found between contrasting innovations for adaptability or acceptance. CONCLUSIONS: Results suggest that organizational members rate contrasting dimensions of an innovation differentially, depending on the nature of the specific innovation. Managers can employ this information as a diagnostic tool to evaluate the fit of an innovation, anticipate problems arising as a result of innovation, and modify innovations to reflect the changes that stakeholders deem necessary. Computerization efforts such as this one are at the cutting edge of efforts to improve the dissemination of information to the public. These efforts can result in considerable improvements in public health.

Automation↗

PubMedDate not supplied

Toxoplasma serology in Zambian and Ugandan patients infected with the human immunodeficiency virus.

In the USA and Europe, toxoplasmosis is well recognized as an important cause of morbidity and mortality among immunocompromised individuals. Toxoplasma gondii has been shown to be a common opportunistic infection in patients infected with the human immunodeficiency virus (HIV) in the USA and Europe with published estimates ranging from 20% to 80%. The importance of Toxoplasma infection in East Africa has not yet been defined. The seroprevalence rates of toxoplasmosis in Zambian and Ugandan patients were determined using the dye test (DT) and the latex agglutination test (LAT). The geographical variation in seroprevalence rates noted in western countries was also found in these African countries, with Zambia showing significantly lower rates than Uganda. 34% of Ugandan (64/186) and 4% of Zambian (8/187) patients infected with HIV, compared with 27% of Ugandan (26/93) and 11% of Zambian (20/189) HIV-negative persons, had anti-Toxoplasma immunoglobulin G antibodies. With the LAT, 13% of the Ugandan and 7% of the Zambian sera gave a false positive result. The relevance of Toxoplasma serology in Africa is discussed.

Antibodies, Protozoan↗

PubMedDate not supplied

Protein turnover in rat placenta: effects of maternal fasting and maternal protein restriction.

Biochemical composition and variables of protein turnover were determined in rat placenta at 21 days gestation in control animals and in animals subjected to 72-h fasting and protein/calorie restriction (6 per cent protein) throughout gestation. Placental protein synthesis was determined following the injection of 'massive' amounts of 14C-phenylalanine intravenously to the pregnant rat. Protein content was reduced in placentas from rats that were fasted for 72 h and in those who were protein restricted throughout pregnancy. Placental RNA content was significantly reduced only in the protein-restricted animals. Fractional rates of protein synthesis were reduced in placentas from the protein-restricted animals (Ks = 17.9 +/- 0.8 per cent per day in controls versus 11.7 +/- 0.9 in protein restricted, P = 0.002), but not in fasted animals. Fractional protein breakdown was markedly enhanced in placentas following maternal fasting (Kd = 9.9 per cent per day in controls versus 26.0 per cent in fasted), but not affected by protein deprivation. These results mimic those previously reported for other fetal tissues under these experimental conditions.

Animals↗

PubMedDate not supplied

Mutation of highly conserved arginine residues disrupts the structure and function of annexin V.

BACKGROUND: Annexins are a family of structurally related proteins that bind to phospholipid membranes in a Ca(2+)-dependent manner. Annexins are characterized by highly conserved canonical domains of approximately 70 amino acids. Annexin V contains four such domains. Each of these domains has a highly conserved arginine (R). METHODS: To evaluate the role of the conserved arginines in the molecular structure of annexin V, negatively charged amino acids were substituted for arginines at positions R43, R115, R199, and R274 using site-directed mutagenesis. RESULTS: Mutants R199D and R274E were rapidly degraded when expressed in bacteria, and were not further characterized. R43E exhibited an electrophoretic mobility similar to the wild-type protein, while R115E migrated significantly in a slower fashion, suggesting a less compact conformation. R43E and R115E exhibited much greater susceptibility to proteolytic digestion than the wild type. While Ca(2+)-dependence for phospholipid binding was similar in both mutants (half-maximal 50-80 microM Ca2+), R43E and R115E exhibited a 6- and 2-fold decrease in phospholipid affinity, respectively. Consistent with the different phospholipid affinities of the annexins, a phospholipid-dependent clotting reaction, the activated partial thromboplastin time (aPTT), was significantly prolonged by the wild-type protein and mutants R115E and R115A. The aPTT was unaffected by R43E. CONCLUSIONS: Our data suggest that mutation of these highly conserved arginine residues in each of the four canonical domains of annexin have differential effects on the phospholipid binding, tertiary structure, and proteolytic susceptibility of annexin V. The site I mutation, R43E, produced a large decrease in phospholipid affinity associated with an increase in proteolytic susceptibility. The site II mutation, R115E, produced a small change in phospholipid binding but a significant modification of electrophoretic mobility. Our data suggest that highly conserved arginine residues are required to stabilize the tertiary structure of annexin V by establishing hydrogen bonds and ionic bridges.

Amino Acid Sequence↗

PubMedDate not supplied

Multi-level adaptive segmentation of multi-parameter MR brain images.

MR brain image segmentation into several tissue classes is of significant interest to visualize and quantify individual anatomical structures. Traditionally, the segmentation is performed manually in a clinical environment that is operator dependent and may be difficult to reproduce. Though several algorithms have been investigated in the literature for computerized automatic segmentation of MR brain images, they are usually targeted to classify image into a limited number of classes such as white matter, gray matter, cerebrospinal fluid and specific lesions. We present a novel model-based method for the automatic segmentation and classification of multi-parameter MR brain images into a larger number of tissue classes of interest. Our model employs 15 brain tissue classes instead of the commonly used set of four classes, which were of clinical interest to neuroradiologists for following-up with patients suffering from cerebrovascular deficiency (CVD) and/or stroke. The model approximates the spatial distribution of tissue classes by a Gauss Markov random field and uses the maximum likelihood method to estimate the class probabilities and transitional probabilities for each pixel of the image. Multi-parameter MR brain images with T(1), T(2), proton density, Gd+T(1), and perfusion imaging were used in segmentation and classification. In the development of the segmentation model, true class-membership of measured parameters was determined from manual segmentation of a set of normal and pathologic brain images by a team of neuroradiologists. The manual segmentation was performed using a human-computer interface specifically designed for pixel-by-pixel segmentation of brain images. The registration of corresponding images from different brains was accomplished using an elastic transformation. The presented segmentation method uses the multi-parameter model in adaptive segmentation of brain images on a pixel-by-pixel basis. The method was evaluated on a set of multi-parameter MR brain images of a twelve-year old patient 48h after suffering a stroke. The results of classification as compared to the manual segmentation of the same data show the efficacy and accuracy of the presented methods as well as its capability to create and learn new tissue classes.

Algorithms↗

PubMedDate not supplied

Identification of organic N-chloramines in vitro in stomach fluid from the rat after chlorination.

Amino acids were identified and quantified in the stomach fluid recovered from animals fasted 8, 24, and 48 h. After in vitro chlorination of stomach fluid, three chloramino acids, N-chloroglycine, either N-chloroleucine or N-chloroisoleucine, and N-chlorophenylalanine, were identified by GC/MS analysis of dansylated methyl ester derivatives. Formation of N-chlorovaline and N-chloroserine was suggested by their HPLC retention times, but their identification could not be confirmed by GC/MS data.

Animals↗

PubMedDate not supplied

Women's preferences for cancer-related information from specific types of mass media.

We examined women's preferences for specific types of cancer-related information from three different mass media: television, newspapers, and magazines. Statistical analyses revealed significant content differences across the three media. These results raise important issues for health marketing campaigns, suggesting that women prefer to receive specific information about cancer, prevention information, and information relating to dealing emotionally with cancer from certain types of mass media.

Adult↗

PubMedDate not supplied

Spontaneous clostridial empyema and pyopneumothorax.

Five patients developed pleural empyema due to Clostridium perfringens in the absence of penetration of the thorax; two of the patients presented with pyopneumothorax. Thirteen additional cases from the literature are reviewed. Predisposing factors to the development of pleural empyema appear to include aspiration pneumonia, pulmonary embolization and infarction, and bacteremia from other foci. Pleural disease and pulmonary tuberculosis may also predispose patients to pleural empyema. Treatment consists of drainage and antimicrobial chemotherapy.

Adult↗

PubMedDate not supplied

Radiology in the diagnosis of splenic abscess.

Radiologic findings in 20 patients with splenic abscesses were reviewed. Chest roentgenograms frequently showed abnormalities which were nonspecific and nondiagnostic. Results of barium sulfate studies were normal in 66.7% of patients tested. Gas beneath the left side of the diaphragm or within the splenic shadow was revealed by abdominal plain film or barium sulfate study in three patients. Focal splenic abnormalities were present in 50% of the patients who underwent 99mTc sulfur colloid scans; in 71.4% of patients who underwent 67Ga scans, increased uptake of isotope was seen in the left upper quadrant of the abdomen. In only one of six patients who underwent both 99mTc and 67Ga scans did results show corresponding abnormalities. Pathologic findings in the left upper quadrant of the abdomen were detected by ultrasonography in three of five patients. Angiography confirmed splenic abscess in one patient. Abnormal splenic lucencies were seen on computed tomography in four patients, although one repeat scan was interpreted as normal. Although no one technique consistently detected splenic abscesses and data from several studies are combined, computed tomography appears the best modality. The diagnosis of splenic abscess and the decision for surgical intervention should be based on clinical impressions, even in the absence of unequivocal radiologic findings.

Abscess↗

PubMedDate not supplied

Quantification of expired metabolites following potassium cyanide administration: a new method.

A sensitive and specific radiolabel method for measuring expired hydrogen cyanide (HCN) or carbon dioxide (CO2) derived from cyanide was developed. An ethanol collecting solution containing a 10(-2) M of cobalt chloride trapped 88% of the H14CN passed through the solution following acid volatilization of a known amount of K14CN. The range of linearity, r = 0.998, exceeded the 0.01 to 0.1 mumoles tested for measuring the pulmonary metabolites. The cobalt chloride collecting solution trapped less than 0.02% of the 10 to 100 mumoles of 14CO2 generated by acid hydrolysis of 14C-sodium bicarbonate (NaH14CO3). Introduction of a second collecting solution specific for CO2, composed of ethanol: ethanolamine (2:1, v/v), was used to collect the CO2 derived from cyanide. Following the subcutaneous (sc) administration of 4.6 mg/kg of potassium cyanide (KCN) and 4.5 microcuries (microCi) K14CN, 1 to 2% and 2 to 3% of the dose was expired as H14CN and 14CO2, respectively.

Animals↗

PubMedDate not supplied

Dietary vitamin D toxicity in a household of pot-bellied pigs (Sus scrofa).

Vitamin D intoxication developed in Vietnamese Pot-Bellied Pigs (Sus scrofa) fed 2 commercially available swine rations. Pronounced hypercalcemia and a history incompatible with other causes of hypercalcemia led to confirmation of this diagnosis by plasma vitamin D metabolite analysis in 2 affected animals as compared to a control animal. Feed sample analysis suggested the diet as the likely source of toxicity.

Animal Feed↗

PubMedDate not supplied

Government as medical ethicist.

Explore the source record for details and available documents.

Ethics, Medical↗