Clinical and molecular analysis of combined hepatocellular-cholangiocarcinomas

BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC.     

New thioredoxin targets in the unicellular photosynthetic eukaryote Chlamydomonas reinhardtii

Proteomics were used to identify the proteins from the eukaryotic unicellular green alga Chlamydomonas reinhardtii that can be reduced by thioredoxin. These proteins were retained specifically on a thioredoxin affinity column made of a monocysteinic thioredoxin mutant able to form mixed disulfides with its targets. Of a total of 55 identified targets, 29 had been found previously in higher plants or Synechocystis, but 26 were new targets. Biochemical tests were performed on three of them, showing a thioredoxin-dependent activation of isocitrate lyase and isopropylmalate dehydrogenase and a thioredoxin-dependent deactivation of catalase that is redox insensitive in Arabidopsis. In addition, we identified a Ran protein, a previously uncharacterized nuclear target in a photosynthetic organism. The metabolic and evolutionary implications of these findings are discussed.     

Macrophage LRP1 contributes to the clearance of von Willebrand factor

The relationship between low-density lipoprotein receptor-related protein-1 (LRP1) and von Willebrand factor (VWF) has remained elusive for years. Indeed, despite a reported absence of interaction between both proteins, liver-specific deletion of LRP1 results in increased VWF levels. To investigate this discrepancy, we used mice with a macrophage-specific deficiency of LRP1 (macLRP1(-)) because we previously found that macrophages dominate VWF clearance. Basal VWF levels were increased in macLRP1(-) mice compared with control mice (1.6 ± 0.4 vs 1.0 ± 0.4 U/mL). Clearance experiments revealed that half-life of human VWF was significantly increased in macLRP1(-) mice. Ubiquitous blocking of LRP1 or additional lipoprotein receptors by overexpressing receptor-associated protein in macLRP1(-) mice did not result in further rise of VWF levels (0.1 ± 0.2 U/mL), in contrast to macLRP1(+) mice (rise in VWF, 0.8 ± 0.4 U/mL). This points to macLRP1 being the only lipoprotein receptor regulating VWF levels. When testing the mechanism(s) involved, we observed that VWF-coated beads adhered efficiently to LRP1 but only when exposed to shear forces exceeding 2.5 dyne/cm(2), implying the existence of shear stress-dependent interactions. Furthermore, a mechanism involving β2-integrins that binds both VWF and LRP1 also is implicated because inhibition of β2-integrins led to increased VWF levels in control (rise, 0.19 ± 0.16 U/mL) but not in macLRP1(-) mice (0.08 ± 0.15 U/mL).     

Alertness and psychomotor performance effects of the histamine-3 inverse agonist MK-0249 in obstructive sleep apnea patients on continuous positive airway pressure therapy with excessive daytime sleepiness: a randomized adaptive crossover study

Objectives

We aimed to evaluate the efficacy of the selective H3 receptor inverse agonist MK-0249 to treat excessive daytime sleepiness (EDS).

Methods

In this three-period, double-blind, crossover study, 125 patients (100 men, 25 women; mean age, 48.6 years) with obstructive sleep apnea receiving nasal continuous positive airway pressure therapy who had refractory EDS were randomized to 2 weeks each of daily MK-0249 (5, 8, 10, or 12 mg, adaptively assigned), modafinil 200 mg, and placebo. At baseline and after each treatment period, six maintenance of wakefulness tests (MWT) and Psychomotor Vigilance Tasks (PVT) were conducted at 2-h intervals, beginning 1 h postdose (∼09:00). The Epworth sleepiness scale (ESS), Clinical Global Impression of Severity (CGIS) and Digit Symbol Substitution Test (DSST) also were assessed. The primary end point was MWT sleep latency averaged over the first four time points (MWT-early).

Results

MWT-early mean change from baseline sleep latency at week 2 was 1.2 min for placebo, 2.1 min for MK-0249 (top two doses pooled; P > .05 vs placebo), and 5.9 min for modafinil (P ? .001 vs placebo). MK-0249 showed improvements vs placebo on secondary and exploratory end points of ESS, CGIS, PVT, and DSST. Insomnia adverse events (AEs) were greater for MK-0249 (combined doses, 17.5%) than for placebo (0.9%) or modafinil (1.8%).

Conclusion

MK-0249 did not significantly affect MWT sleep latency. However, the pattern of improvement on subjective ratings and psychomotor performance end points suggested that MK-0249 was associated with changes in aspects of cognition and performance not captured by the MWT.     

Physiologic and behavioral responses to stress,temperament, and incidence of infection and atopic disorders in the first year of life: a pilot study

The purpose of this pilot study was to explore relationships among physiologic and behavioral responses to a standardized stressor (routine immunization), parent-reported temperament, and numbers of infections and atopic disorders in the first year of life. Infants were studied during 2- (n = 30) and 4-month (n = 24) routine clinic visits. Behavioral data were coded from videotapes filmed for 90 seconds after immunizations. Salivary cortisol measured physiologic arousal; specimens were obtained before and after immunizations. Two-month-old infants with higher levels of cortisol required more time to calm after immunization. Relationships were found between the temperament characteristics of persistence and adaptability and infections at 12 months.     

Obesity and the risk for cardiovascular disease

Coronary heart disease (CHD) is the leading cause of mortality in the United States. Hypertension, diabetes mellitus, hypercholesterolemia, and smoking have all been directly related to CHD. Obesity is on the rise in the United States and has also been associated with CHD. This review clearly establishes obesity as an independent risk factor for CHD as demonstrated by the Framingham Heart Study, Nurses' Health Study, Buffalo Health Study, and the Cancer Prevention Study II. Morbid obesity was found to correlate with a significant risk of mortality from CHD, especially in young men. Prevention of obesity, and therefore reduction in risk from cardiovascular disease, is paramount in the management of obesity. New approaches to behavioral, medical, and surgical management of obesity are reviewed, including thalidomide, an antiangiogenic agent. A primary and secondary prevention model details a multidisciplinary approach to reducing risk in obesity.     

Detection ofPneumocystis carinii with direct fluorescence antibody and calcofluor white stain

Summary Direct fluorescence monoclonal antibody stain (DFA) was compared prospectively, with calcofluor white (CFW) stain for the diagnosis ofPneumocystis carinii in 163 respiratory specimens from 97 patients. The patient population included persons with HIV infection (58%), bone marrow transplant recipients (10%), immunosuppressed patients owing to chemotherapy (21%) and others (11%). Nineteen specimens including 12 sputa, six bronchoalveolar lavage fluids (BALs) and one induced sputum were positive by DFA. In contrast, only six sputa, and five BALs were positive by CFW. All specimens positive by CFW were also positive by DFA. Of 86 sputa that were negative by either method 29 were followed by more invasive sample collections. Three specimens were followed by induced sputum collection, 18 by BAL, six by lung biopsy, and two by pleural fluid aspiration. All the subsequent induced sputa, pleural fluids, and lung biopsies were negative by both methods. However, four of 18 subsequent BALs (22%) were positive by both methods, provided at least two CFW stained slides were examined per specimen. Except for expectorated sputum, it is concluded that CFW is a rapid and inexpensive test to detectP. carinii in most respiratory specimens.

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Nachweis vonPneumocystis carinii mit direkter Antikörper-Fluoreszenztechnik (DFA) und Calcofluor Weiß-Färbung

Zusammenfassung Im prospektiven Vergleich wurde die diagnostische Aussagekraft der direkten Antikörper-Fluoreszenz-Technik und der Calcofluor-Weiß (CFW)-Färbung zum Nachweis vonPneumocystis carinii in 163 Proben aus dem unteren Respirationstrakt von 97 Patienten geprüft. Die Gruppe setzte sich aus Patienten mit HIV-Infektion (58%), Knochenmarktransplantations-Empfängern (10%), nach Chemotherapie immunsupprimierten Patienten (21%) und anderen (11%) zusammen. Mit DFA-Technik waren 19 Proben positiv; darunter waren 12 Sputumproben, sechs bronchoalveoläre Lavage (BAL)-Flüssigkeiten und ein induziertes Sputum. Mit CFW-Färbung waren sechs Sputumproben und fünf BAL-Proben positiv. Alle mit CFW positiven Proben waren auch mit DFA positiv. Eine erneute Probenahme mit invasiveren Methoden erfolgte in 29 von 86 mit beiden Nachweis-Verfahren negativen Fällen. In drei Fällen wurde induziertes Sputum gewonnen, in 18 Fällen eine BAL, in sechs Fällen eine Lungenbiopsie und in zwei Fällen eine Pleurapunktion durchgeführt. Alle in der Folge gewonnenen induzierten Sputa, Pleuraflüssigkeiten und Lungenbiopsien waren mit beiden Methoden negativ. Doch in vier der 18 BAL-Flüssigkeiten (22%) wurdeP. carinii nachgewiesen, dabei waren mindestens zwei mit CFW gefärbte Ausstriche pro Probe untersucht worden. Mit Ausnahme von Spontansputum eignet sich die CFW-Färbung als einfaches und billiges Verfahren bei den meisten Proben aus den tiefen Atemwegen zum Nachweis vonP. carinii.