Transfection of wild-type deoxycytidine kinase (dck) cDNA into an AraC- and DAC-resistant rat leukemic cell line of clonal origin fully restores drug sensitivity

The AraC-resistant rat leukemic cell line RO/1-A has been shown to have a typical deoxycytidine kinase (DCK)-deficient phenotype and cannot metabolize the antileukemic drugs cytarabine (AraC) and decitabine (DAC). To investigate the relative contribution of mutations in the dck gene to the development of in vitro-induced AraC-resistance, a neomycin selectable plasmid construct harboring the wild-type dck coding region was transfected into RO/1-A. Polymerase chain reaction analysis confirmed the presence of vector DNA in the target cells (RO/1-ADCK) that were stably transfected and monitored over a period of 14 weeks. Northern and Western blot analysis showed restoration of dck mRNA and protein expression. Initial rate measurements of DCK activity showed that Km values for dck were only slightly altered as a result of transfection, whereas strongly increased Vmax values were observed, resulting in a 12-fold increased phosphorylation efficiency for both dC and AraC, compared with the AraC-sensitive parental cell line RO/1 from which the RO/1-A was originally derived. In vitro sensitivity to AraC- and DAC-mediated cytotoxicity was fully restored in RO/1-ADCK. The data pinpoint acquired DCK deficiency caused by mutations of the dck gene as the major cause of AraC resistance in this model.     

Extrapancreatic spread of acute pancreatitis: new observations with real-time US

Real-time ultrasonography (US) was compared with abdominal computed tomography (CT) in 40 patients with moderate to severe acute pancreatitis. Emphasis was placed on the ability of US to disclose peripancreatic involvement of the anterior pararenal spaces, lesser sac, and transverse mesocolon. When a realtime US scanning technique emphasizing semierect patient positioning and coronal views was used, 20 of 26 lesions in the anterior pararenal space (77%) and 14 of 14 abnormalities in the lesser sac (100%) were visualized. Abnormalities in the transverse mesocolon, however, were poorly detected on US scans. Ten patients (25%) in the study had extrapancreatic abnormalities missed by US. CT remains the imaging method of choice in patients with clinically moderate to severe pancreatitis. In patients with mild pancreatitis, the real-time US technique we describe improved extra-pancreatic visualization compared with previous studies using static scanners. A new US observation of perivascular spread of acute pancreatitis around the splenic and portal veins is described.     

Stenosis of individual pulmonary veins: radiologic findings

Congenital stenosis of individual pulmonary veins is uncommon. Of the 49 cases reported, four were seen at the IWK Hospital for Children and are reported here. Plain radiographs show a shift of the heart toward the side of major involvement, Kerley B lines, fluid in the fissures, and interstitial edema of the affected lobes. These findings, while subtle, should nevertheless suggest stenosis. Technetium-99m macro-aggregate lung perfusion scans show absence of or diminished perfusion of the affected lobes. The diagnosis can usually be confirmed with angiography. Congenital stenosis of individual pulmonary veins should be considered in children with repeated pulmonary infections, dyspnea, failure to thrive, hemoptysis, or unexplained pulmonary hypertension.     

Chronic osteomyelitis examined by CT

CT examination of 25 patients who had acute exacerbations of chronic osteomyelitis allowed for the correct identification of single or multiple sequestra in 14 surgical patients. Plain radiographs were equivocal for sequestra in seven of these patients, because the sequestra were too small or because diffuse bony sclerosis was present. CT also demonstrated a foreign body and five soft tissue abscesses not suspected on the basis of plain radiographs. CT studies, which helped guide the operative approach, were also useful in treating those patients whose plain radiographs were positive for sequestra. We review the potential role of CT in evaluating patients with chronic osteomyelitis.     

Proton imaging for medical applications

In order to demonstrate the potential advantages of proton imaging for medical use, a 205-MeV proton beam was developed using the Argonne National Laboratory Booster I synchrotron. Data were taken using a narrow scanning beam and an electronic detector system. The dose reduction and an improved mass resulution over the radiographs. The images also show significant differences in the proton stopping power of different tissues, thus demonstrating considerable potential in soft-tissue imaging. The development of a proton tomographic scan system is also briefly discussed.     

HEALTH AWARENESS VERSUS ECONOMIC AFFLUENCE AS DETERMINANTS OF HEALTH STATUS : A COMMUNITY BASED EPIDEMIOLOGICAL ANALYSIS

A community-based cross-sectional analytic epidemiological study was undertaken to compare the health status of school children from two villages and to see the association of the school children''s health status with the level of health awareness among parents and teachers. The two villages had only one major difference, i.e., one had an agriculture-based economy and was more affluent than the other village. The study, however, revealed that the overall morbidity and nutritional deficiencies were significantly less (p < 0.01) and immunization status significantly better (p < 0.01) among school children of the less affluent village, possibly because level of health awareness was significantly higher among parents and teachers of this village as compared to the more affluent one (p < 0.01). The importance of health education has been reinforced by this study.KEY WORDS: Health status, Health planning, Health education