Hilar cholangiocarcinoma: thin-section spiral CT findings with cholangiographic correlation

Hilar cholangiocarcinoma, a highly lethal tumor, is difficult to diagnose with conventional computed tomography (CT) because of its small size. Spiral CT allows more effective evaluation of these small lesions and better demonstrates the status of the hepatic arterial or portal venous circulation. Among 27 patients with hilar cholangiocarcinoma (infiltrative in 21, exophytic in two, polypoid in one, diffuse in three), thin-section spiral CT allowed identification of each tumor as an area of focal wall thickening that obliterated the lumen. Seventeen of the infiltrative tumors (81%) showed high attenuation. Identification of the level of biliary obstruction was possible in 63% of the patients (17 of 27). The level of obstruction was underestimated in six patients and overestimated in four. Spiral CT is a valuable method for diagnosis of hilar cholangiocarcinoma; however, spiral CT is less accurate in evaluation of intraductal tumor extent because of the limited z-axis resolution.     

Increased restenosis in diabetes mellitus after coronary interventions is due to exaggerated intimal hyperplasia. A serial intravascular ultrasound study

Hepatic hydrothorax is a rare complication of portal hypertension. Conservative therapy may be successful but refractory hepatic hydrothorax is not uncommon. Management of refractory hydrothorax is usually ineffective and can result in a worsened clinical status. Transjugular intrahepatic portosystemic shunts (TIPS) lower portal pressure and have been used in the treatment of refractory ascites. The aim of this study was to determine the efficacy of TIPS in the treatment of symptomatic refractory hepatic hydrothorax. A TIPS was placed in 24 consecutive cirrhotic patients with symptomatic refractory hepatic hydrothorax. Five patients (20.8%) were Child's/Pugh class B and 19 (79.2%) were class C. All had undergone multiple thoracenteses and were hypoalbuminemic. Mean follow-up was 7.2 months (range, 0.25-49 months). Fourteen (58.3%) of 24 patients had complete relief of symptoms after shunt placement and did not require further thoracentesis. Five (20.8%) additional patients required fewer thoracenteses. Five (20.8%) patients developed worsening liver function and died within 45 days. In eight (66.7%) of 12 patients with > or = 60 days of follow-up, the serum albumin increased by a mean of 1.2 g/dL (range, 0.1-2.2 g/dL). The Child's-Pugh score improved in 7 (58.3%) of these 12 patients and two patients improved from class C to class A. These two patients no longer require liver transplantation. This study shows that TIPS can be effective in the management of symptomatic, refractory hepatic hydrothorax. Clinical and laboratory improvement may be seen and liver transplantation may become unnecessary.     

Duration of homologous porcine reproductive and respiratory syndrome virus immunity in pregnant swine

The clinical consequences of single or multiple exposure of pregnant gilts to porcine reproductive and respiratory syndrome virus (PRRSV) at various stages of gestation were determined. Thirty-three pregnant gilts were allotted to 6 experimental groups (5 to 7 gilts/group). Gilts of groups 1 to 5 were exposed to strain NADC-8 of PRRSV at the following times: group 1, gestation day (GD) 1; group 2, GDs 1 and 90; group 3, GD 30; group 4, GDs 30 and 90; group 5, GD 90. Virus exposure was by either intrauterine (GD 1) or oronasal (GDs 30 and 90) inoculation. Gilts of group 6 were kept as nonexposed controls. Gilts were either necropsied on or about GD 111 (groups 1 to 5) or were allowed to farrow (group 6). The detection of PRRSV in serum of fetuses and piglets (within 12 hof birth) was considered evidence of transplacental infection. Transplacental infection and virus-induced death were and were not confirmed for groups 3, 4, and 5 and for groups 1, 2, and 6, respectively. Collectively, the results indicated that intrauterine exposure to PRRSV at GD 1 was without clinical effect (groups 1 and 2) and provided protection against subsequent exposure to the same strain of virus at GD 90 (group 2). The highest incidence of transplacental infection and fetal death followed a single exposure to PRRSV at GD 90 (group 5).     

Cloning and functional expression of a human liver organic cation transporter

OBJECTIVE: The triglyceride-lowering effects of omega-3 fats and HDL cholesterol-raising effects of exercise may be appropriate management for dyslipidemia in NIDDM. However, fish oil may impair glycemic control in NIDDM. The present study examined the effects of moderate aerobic exercise and the incorporation of fish into a low-fat (30% total energy) diet on serum lipids and glycemic control in dyslipidemic NIDDM patients. RESEARCH DESIGN AND METHODS: In a controlled, 8-week intervention, 55 sedentary NIDDM subjects with serum triglycerides > 1.8 mmol/l and/or HDL cholesterol < 1.0 mmol/l were randomly assigned to a low-fat diet (30% daily energy intake) with or without one fish meal daily (3.6 g omega-3/day) and further randomized to a moderate (55-65% VO2max) or light (heart rate < 100 bpm) exercise program. An oral glucose tolerance test (75 g), fasting serum glucose, insulin, lipids, and GHb were measured before and after intervention. Self-monitoring of blood glucose was performed throughout. RESULTS: In the 49 subjects who completed the study, moderate exercise improved aerobic fitness (VO2max) by 12% (from 1.87 to 2.07 l/min, P = 0.0001). Fish consumption reduced triglycerides (0.80 mmol/l, P = 0.03) and HDL3 cholesterol (0.05 mmol/l, P = 0.02) and increased HDL2 cholesterol (0.06 mmol/l, P = 0.01). After adjustment for age, sex, and changes in body weight, fish diets were associated with increases in GHb (0.50%, P = 0.05) and self-monitored glucose (0.57 mmol/l, P = 0.0002), which were prevented by moderate exercise. CONCLUSIONS: A reduced fat diet incorporating one daily fish meal reduces serum triglycerides and increases HDL2 cholesterol in dyslipidemic NIDDM patients. Associated deterioration in glycemic control can be prevented by a concomitant program of moderate exercise.     

A case of paraquat poisoning and subsequent fatality presenting to an emergency department

Paraquat (1,1'-dimethyl-4,4'-dipyridylium) is an herbicide associated with both accidental and intentional ingestion, leading to severe and often fatal toxicity. Prognosis is largely dependent on the amount of paraquat absorbed. Rapid identification of the symptoms of paraquat toxicity (burns or ulceration at the site of ingestion or injection, acute respiratory distress, and renal failure) can facilitate early treatment intervention to limit absorption. We report a case of a 71-year-old man with a suicidal ingestion of paraquat 2 days prior to presentation. Serum paraquat levels, time elapsed since ingestion, and clinical symptoms all indicated poor prognosis. The patient developed severe respiratory distress and progressive renal failure, and died 6 days after admission to the hospital.     

The roles of conserved carboxylate residues in IMP dehydrogenase and identification of a transition state analog

IMP dehydrogenase (IMPDH) catalyzes the oxidation of IMP to XMP with the concomitant reduction of NAD+; the enzyme is activated by K+. This reaction is the rate-limiting step in de novo guanine nucleotide biosynthesis. In order to identify functionally important residues in IMPDH, including those involved in substrate and K+ binding, we have mutated 11 conserved Asp and Glu residues to Ala in Escherichia coli IMPDH. The values of kcat, Km, and Ki for GMP, XMP, mizoribine 5'-monophosphate (MMP), and beta-methylene-tiazofurin adenine dinucleotide (TAD) were determined. Five of these mutations caused a significant change (>/=10-fold) in one of these parameters. The Asp248 --> Ala mutation caused 100-fold decrease in the value of kcat and a 25-fold increase in the value of Kii for TAD; these observations suggest that Asp248 is in the NAD+ binding site. The Asp338 --> Ala mutation caused a 600-fold decrease in the value of kcat, but only a 5-10-fold increase in the values of Km for IMP and Kis for IMP analogs, suggesting that Asp338 may be involved in acid-base catalysis as well as IMP binding. The remaining three residues, Asp13, Asp50, and Glu469, appear to be involved in K+ activation; these residues may be ligands at one or more K+ binding sites. Interestingly, changes in the values of Ki for MMP correlate with changes in kcat/KmKm of IMPDH, while no such correlation is observed for GMP, XMP, and TAD. This observation indicates that MMP is a transition state analog for the IMPDH reaction.     

Epidemiology of falls among the elderly community dwellers in Singapore

AIM: Falling is a serious medical problem for elderly persons. This study was done to look at prevalence and risk factors for falls in community dwelling elderly in Singapore. METHOD: A random sample of 3,000 persons aged 60 years and above was chosen from a database based on the 1990 population census. Letters were sent out to 2,582 subjects who had local and complete addresses. In the letter, they were informed about the purpose of the survey, and invited to participate in a questionnaire and clinical health screening at an appointed date at a polyclinic. Participants were reminded the day before their appointment by telephone, and a new appointment could be given at the subject's convenience. RESULTS: We found a prevalence rate of falls of 17.2%. Two-thirds of these had single falls, while one-third had recurrent falls, defined as having more than one fall within the previous one year. The following factors were found to be significantly associated with increase falling in the elderly: age > or = 75 years (O.R. = 1.82, 95% C.I. 0.95-3.50), female sex (O.R. = 2.5, 95% C.I. 1.40-4.48), Malay race (O.R. = 2.66, 95% C.I. 1.21-5.86), poor vision (O.R. = 1.7, 95% C.I. 0.99-2.90), Barthel's score of less than 20 (O.R. = 1.76, 95% C.I. 0.94-3.28), those taking 2 or more drugs daily (O.R. = 2.1, 95% C.I. 1.22-3.72) and the presence of hypertension (O.R. = 1.78, 95% C.I. 1.06-3.01). Fall rate is also twice as high in women as in men. At the same time, we found that women in the group we studied also tend to exercise less than the men. Fallers also had significantly more mobility and activities of daily living (ADL) disabilities (reflected by a lower Barthel's score) and this is consistent with other results. The only factor that reduced the risk of falling was regular exercise (O.R. = 1.64, 95% C.I. 0.93-2.93). CONCLUSION: In our study, we found differences between the group with single and recurrent falls. In the group with single falls, the fall tend to occur outdoors (O.R. = 2.97, 95% C.I. 1.03-8.60) and during the day (O.R. = 3.47, 95% C.I. 1.20-10.0), tend to be accidental (O.R. = 3.16, 95% C.I. 1.05-9.50) and tend to seek medical attention (O.R. = 3.68, 95% C.I. 1.23-11.0). Overall, 32 persons (46.4%) seek medical treatment after their falls, and of these, 65.6% were women. Risk factors for falls should be screened for all elderly.     

Contributions of the left and right cerebral hemispheres to line bisection

Thirty-one right-hemisphere lesioned (RHL) patients, 11 left-hemisphere lesioned patients (LHL) and 10 normal controls (NC) bisected lines in three spatial location and four directional cuing conditions. The error direction and error size were analyzed as separate and combined variables. Seventy-seven percent of RHL patients and 45% of LHL patients made abnormally large errors in line bisection. Right-hemisphere lesioned patients were more sensitive to spatial location and directional cuing than NC subjects. In contrast, LHL patients were less sensitive to either condition than NCs. The error direction and error size emerged as dissociable components of line bisection. Right-hemisphere lesioned patients and NC subjects bisected lines consistently to one side of the true center. Left-hemisphere lesioned patients bisected lines equally often on both sides of the true center. Both RHL and LHL patients made larger absolute bisection errors than NC subjects, but the RHL patient's errors were larger than those of the LHL patients. We propose that the greater sensitivity of RHL patients to spatial location and directional cues and the directional consistency of their bisection errors represent contributions of the intact left cerebral hemisphere to line bisection. In contrast, the LHL patient's unrestrained ability to orient to both ends of the line reflects a contribution of the intact right cerebral hemisphere to line bisection. The failure of both groups to accurately bisect lines reflects a common visuospatial processing deficit that is more pronounced following RHLs than LHLs.     

The Spallator and APEX Nuclear Fuel Cycle a New Option for Nuclear Power

A new nuclear fuel cycle is described which provides a long term supply of nuclear fuel for the thermal LWR nuclear power reactors and eliminates the need for long-term storage of radioactive waste. Fissile fuel is produced by the Spallator which depends on the production of spallation neutrons by the interaction of high energy (1 to 2 GeV) protons on a heavy metal target. The neutrons are absorbed in a surrounding natural uranium or thorium blanket in which fissile Pu-239 or U-233 is produced. Advances in linear accelerator technology makes it possible to design and construct a high beam current continuous wave proton linac for production purposes. The target is similar to a sub-critical reactor and produces heat which is converted to electricity for supplying the linac. The Spallator is a self-sufficient fuel producer, which can compete with the fast breeder. The APEX fuel cycle depends on recycling the transuranics and long-lived fission products while extracting the stable and short-lived fission products when reprocessing the fuel. Transmutation and decay within the fuel cycle and decay of the short-lived fission products external to the fuel cycle eliminates the need for long-term geological age storage of fission product waste.     

Relationship between soluble CD14, lipopolysaccharide binding protein, and the alveolar inflammatory response in patients with acute respiratory distress syndrome

The effects of bacterial endotoxin (lipopolysaccharide, LPS) are amplified by lipopolysaccharide binding protein (LBP) and CD14, resulting in cellular activation at very low concentrations of LPS. To investigate the importance of this pathway in acute lung injury, we measured LPS, LBP, and soluble CD14 (sCD14) in the bronchoalveolar lavage fluid (BAL) of 82 patients with acute respiratory distress syndrome (ARDS). LBP and sCD14 increased markedly in BAL of patients with ARDS. sCD14 and LBP each were strongly related to BAL total protein and polymorphonuclear neutrophil (PMN) concentration, whereas LPS concentration was not. Multivariate analyses showed sCD14 to be strongly related to BAL total protein, even after controlling for LPS and LBP concentrations. sCD14 was strongly and independently related to PMN concentration, after controlling for BAL LPS, LBP, and interleukin-8 (IL-8). The BAL LPS concentration was not strongly related to either BAL total protein or BAL PMN. The BAL sCD14 and LBP values were similar in all subgroups of patients with ARDS, and were not related to survival. The serum LBP and sCD14 were elevated in ARDS, but were not related to BAL total protein, LBP, sCD14, PMN, or clinical outcome. Thus, LBP and sCD14 reach high concentrations in the lungs of patients with ARDS, and BAL sCD14 is strongly related to two major indices of lung inflammation: total protein and PMN concentration. CD14-dependent mechanisms may contribute to lung inflammation in ARDS.