Increase of paradoxical excitement response during propofol-induced sedation in hazardous and harmful alcohol drinkers

BACKGROUND

Paradoxical excitement response during sedation consists of loss of affective control and abnormal movements. Chronic alcohol abuse has been proposed as a predisposing factor despite lack of supporting evidence. Because alcohol and propofol have a common site of action, we postulated that paradoxical excitement responses during propofol-induced sedation occur more frequently in hazardous and harmful alcohol drinkers than in social or non-drinkers.

METHODS

One hundred and ninety patients undergoing orthopaedic knee joint surgery were enrolled in this prospective and observational study. Subjects were divided into Group HD (hazardous and harmful drinkers) or Group NHD (no hazardous drinkers) according to the alcohol use disorder identification test (AUDIT). In study 1, propofol infusion was adjusted to achieve the bispectral index at 70-80 using target-controlled infusion. In study 2, the target concentration of propofol was fixed at 0.8 (study 2/Low) or 1.4 μg ml(-1) (study 2/High). Paradoxical excitement responses were categorized by intensity into mild, moderate, or severe.

RESULTS

The overall incidence of paradoxical excitement response was higher in Group HD than in Group NHD in study 1 (71.4% vs 43.8%; P=0.022) and study 2/High (70.0% vs 34.5%; P=0.006) but not in study 2/Low. The incidence of moderate-to-severe response was significantly higher in Group HD of study 1 (28.6% vs 3.1%; P=0.0005) and study 2/High (23.3% vs 3.4%; P=0.029) with no difference in study 2/Low. Severe excitement response occurred only in Group HD of study 1 and study 2/High.

CONCLUSIONS

Paradoxical excitement occurred more frequently and severely in hazardous and harmful alcohol drinkers than in social drinkers during propofol-induced moderate-to-deep sedation, but not during light sedation.

Contrast-enhanced computed tomography angiography and volume-rendered imaging for evaluation of cellophane banding in a dog with extrahepatic portosystemic shunt

A 4-year-old, 1.8 kg, male, castrated Maltese was presented for evaluation of urolithiasis. Urinary calculi were composed of ammonium biurate. Preprandial and postprandial bile acids were 44.2 and 187.3 μmol/ , respectively (reference ranges 0–10 and 0–20 μmol/ , respectively). Single-phase contrast-enhanced computed tomography angiography (CTA) with volume-rendered imaging (VRI) was obtained. VRI revealed a portocaval shunt originating just cranial to a tributary of the gastroduodenal vein and draining into the caudal vena cava at the level of the epiploic foramen. CTA revealed a 3.66 mm-diameter shunt measured at the level of the termination of the shunt and a 3.79 mm-diameter portal vein measured at the level between the origin of the shunt and the porta of the liver. Surgery was performed using cellophane banding without attenuation. Follow-up single-phase CTA with VRI was obtained 10 weeks after surgery. VRI revealed no evidence of portosystemic communication on the level of a cellophane band and caudal to the cellophane band. CTA demonstrated an increased portal vein diameter (3.79–5.27 mm) measured at the level between the origin of the shunt and the porta of the liver. Preprandial and postprandial bile acids were 25 and 12.5 μmol/ , respectively (aforementioned respective reference ranges), 3 months post-surgery. No problems were evident at 6 months.

Helicobacter pylori infection as an independent prognostic factor for locally advanced gastric cancer with curative resection

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Background: A few studies reported the association between helicobacter pylori (HP) infection and better overall survival (OS) in resected gastric cancer patients (pts). Methods: We investigated the HP infection status and its association with clinicopathologic characteristics in 210 locally advanced gastric cancer patients (stage IB: 18, II: 61, IIIA: 62, IIIB: 31, IV: 38) who underwent adjuvant chemotherapy (CTX) after curative resection (≥D2 dissection). HP infection status in hematoxlin and eosin stained peritumoral tissue was graded according to the updated Sydney System and categorized as HP(-) (normal or mild infection) and HP(+) (moderate or marked infection) (Am J Surg Pathol 20:1161, 1996). Twenty-two pts received 5-FU, doxorubicin (DOX) CTX (5- FU 500 mg/m2 weekly for 36 wks, DOX 40 mg/m2 q 3 weeks x 12) with or without OK432, while 188 pts underwent 5-FU, mitomycin-C (MMC), and polysaccharide-K (PSK) CTX (5-FU 500 mg/m2 weekly for 24 wks, MMC 8 mg/m2 q 6 wks x 4, PSK 3 g/day for 16 wks) (Br J Cancer 84:186, 2001, Hepatogastroenterol 54:290, 2007). Results: The median follow-up duration of survivors was 125 (107–155) months. HP (-) was significantly correlated with Bormann type IV, larger tumor size (>5.5cm),and stage IIIB. In univariate analysis, patients with HP(-) (104 pts) demonstrated significantly poor 10-year OS compared with those with HP (+) (106 pts) (15.9% vs. 87.7%, p<0.0001). HP(-) was associated with poor outcome in all stages except stage IB (p=0.075). In multivariate analysis, HP(-) was the most significant independent prognostic factor of poor OS (hazard ratio 9.646, 95% CI 5.407–17.206, p<0.0001) followed by advanced stage (p=0.032), Bormann type IV (p=0.037) and old age (p=0.015). Conclusions: HP infection status seems to have strong prognostic significance in locally advanced gastric cancer. HP (-) pts may need intensified adjuvant treatment and careful follow-up.

No significant financial relationships to disclose.

Expression of excision repair cross-complementation group 1 protein and outcome in patients with nasopharyngeal cancer

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Background: We evaluated the prognostic significance of thymidylate synthase (TS), and Excision Repair Cross-Complementation Group 1 protein (ERCC1) in patients (pts) with nasopharyngeal cancer (NPC) treated with concurrent chemoradiotherapy (CCRT). Methods: Pretreatment tumor biopsy specimens from 41 pts with locally advanced NPC were analyzed for TS and ERCC1 expression by immunohistochemistry. All patients were treated with 1 cycle of induction chemotherapy (5-fluorouracil 1,000 mg/m2/day and cisplatin 20 mg/m2/day, days 1–4) followed by CCRT starting on day 22. CCRT consisted of radiotherapy (70Gy/35 fractions for 7 weeks) with cisplatin 20mg/m2/day for 4 days on weeks 1, 4, 7 of radiotherapy. Results: Complete response and partial response were achieved in 34 pts (83%) and 6 pts (15%), respectively. Within median follow up duration of 101 months (26–147months) in survivors, 5-years overall survival (OS) of all pts was 50%. High expression of TS and ERCC1 was observed in 21 (51%) and 25 (60%) pts, respectively. High expression of ERCC1 was associated with WHO type 1 or 2 histology (p = 0.045). In univariate analysis, high expression of ERCC1 was associated with poor OS (5-year: 73% versus 35%; p = 0.005), while high expression of TS was not correlated with pts outcome (p = 0.867). In multivariate analysis, high expression of ERCC1 was a significant independent predictor of poor OS (p = 0.041) along with WHO type 1 or 2 histology (p = 0.004). Conclusions: High expression of ERCC1 protein may be useful for prediction of poor outcome in pts with NPC treated with CCRT.

No significant financial relationships to disclose.

Anomalous circular polarization of photoluminescence spectra of individual CdSe nanocrystals in an applied magnetic field

We study the low-temperature magnetophotoluminescence from individual CdSe nanocrystals. Nanocrystals having a small "bright" exciton fine structure splitting (Delta_{XY}<0.5 meV) exhibit a conventional left and right circularly polarized Zeeman photoluminescence doublet in applied magnetic fields. In contrast, nanocrystals with large Delta_{XY} (>1 meV) show an anomalous magnetophotoluminescence polarization, wherein the lower-energy peak becomes circularly polarized with increasing field, while the higher-energy peak remains linearly polarized. This unusual behavior arises from strong mixing between the absorbing and emitting bright exciton levels due to strong anisotropic exchange interactions.

Clinical outcomes of adjuvant treatments for invasive thymoma: Dose chemotherapy influence prognosis?

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Background: The aim of this study was to evaluate therapeutic outcomes and to validate prognostic factors, including adjuvant chemotherapy, in resected thymoma patients who received adjuvant treatment. Methods: One hundred thymoma patients who received post-surgical adjuvant therapy from 1995 to 2005 were retrospectively reviewed. 55 patients received only radiotherapy for the adjuvant therapy, while 45 patients received both radiotherapy and chemotherapy. The total radiation dose was 45–63 Gy, with a median dose of 50.4 Gy. The chemotherapy consisted of 6 cycles of doxorubicin, cisplatin, vincristine, and cyclophosphamide. Treatments were applied every 3–4 weeks. The median follow-up duration was 65 months (range, 5–200 months). Results: The 5-year overall survival (OS) and disease- free survival (DFS) rates were 75.7% (89.2% in stage II, 67.9% in stage III, and 52.1% in stage IVA) and 70.3% (83% in stage II, 62.4% in stage III, and 33.6% in stage IVA) respectively. According to multivariate analysis, the prognostic factors for OS were age, WHO histology, Masaoka stage, and recurrence, while pleural involvement and WHO histology had statistically significant impacts on DFS. Higher radiation dosage, positive resection margins, and adjuvant chemotherapy did not influence survival outcomes. The most common relapse site was the pleura (15 patients, 53.6%). The toxicity from chemotherapy and radiotherapy was manageable, with no deaths due to toxicity. Conclusion: The prognosis of invasive thymoma was poor despite adjuvant treatments with radiotherapy and chemotherapy. In addition to WHO histology, pleural involvement was the most important prognostic factor for recurrence. The pleura was the most common relapse site. Therefore, new modalities to reduce pleural recurrence are warranted.

No significant financial relationships to disclose.

cT3N0 rectal cancer: Potential overtreatment with preoperative chemoradiation (CRT) is warranted

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Background: Although CRT has emerged as the preferred treatment for T3 and/or lymph node (LN) positive rectal cancer, Sauer et al (NEJM 2004) demonstrated that 18% of patients deemed suitable for preop CRT via endorectal ultrasound (ERUS) were overstaged and therefore received unnecessary preoperative CRT. Since data also suggest that LN negative rectal cancer s/p TME may not need adjuvant therapy, it is reasonable to consider the omission of radiotherapy for the cT3N0 subset. We therefore determined the accuracy of pre-CRT ERUS/MRI staging in order to explore the validity of a non-radiation approach for cT3N0 disease. Methods: 188 ERUS/MRI staged T3N0 rectal cancer patients from 6 insitutions in the US, Europe and Asia received preoperative CRT (5-FU based and 45–52.5 Gy) followed by radical resection. Rates of pathologic complete response (pCR) and mesorectal LN involvement were determined. Results: Tumors were located a median of 5 centimeters from the anal verge. Sphincter-preserving surgery was performed in 135 (81%) patients. Overall pCR was 19%. Median number of LN sampled was 9 (range 0–38). Rate of positive LN was significantly associated with T-stage: pT0: 3%, pT1: 7%, pT2: 20%, pT3–4: 36%(p=0.001). 41 patients (22%) had pathologically positive mesorectal LN. There was no significant difference in rate of positive LN between those staged by ERUS and MRI(25% vs 16%, p=0.19). Conclusions: Accuracy of preoperative ERUS/MRI for identifying mid to distal T3N0 rectal cancer is limited, as 22% will have undetected mesorectal LN involvement despite CRT. Therefore, ERUS/MRI staged T3N0 patients should continue to receive preoperative CRT. Although 19% are overstaged and therefore overtreated, our data suggest that an even larger number would be understaged and require postoperative CRT, which is associated with inferior local control, higher toxicity, and poor functional outcome.

No significant financial relationships to disclose.

Inhibitory effects of the root cortex of Paeonia suffruticosa on interleukin-8 and macrophage chemoattractant protein-1 secretions in U937 cells

In an effort to elucidate the mechanism of the anti-inflammatory effect of mudanpi, the root cortex of Paeonia suffruticosa Andrews (Ranunculaceae), we determined the effects of the methanolic extract of mudanpi (MEM) on the secretions of interleukin (IL)-8, a major mediator of acute neutrophil-mediated inflammation, and macrophage chemoattractant protein (MCP)-1, a major mediator of chronic macrophage-mediated inflammation, in human monocytic U937 cells stimulated with phorbol myristate acetate (PMA). MEM significantly inhibited PMA-induced secretions of IL-8 and MCP-1 proteins in a dose-dependent manner. The inhibition of these chemokines by MEM was due to its suppression of IL-8 and MCP-1 genes. In addition, 1,2,3,4,6-penta-O-galloyl-beta-D-glucose, one of major constituents isolated from MEM, inhibited PMA-induced secretions of IL-8 and MCP-1 proteins by its suppression of IL-8 and MCP-1 genes. Thus, one possible anti-inflammatory mechanism of mudanpi, an anti-inflammatory Chinese crude drug, may be to inhibit the secretions of inflammatory chemokines.

Inhibition of TNF-alpha, IL-1beta, and IL-6 productions and NF-kappa B activation in lipopolysaccharide-activated RAW 264.7 macrophages by catalposide, an iridoid glycoside isolated from Catalpa ovata G. Don (Bignoniaceae)

Catalposide, the major iridoid glycoside isolated from the stem bark of Catalpa ovata G. Don (Bignoniaceae), was found to inhibit the productions of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6), and the activation of nuclear factor kappaB (NF-kappaB) in RAW 264.7 macrophages activated with lipopolysaccharide (LPS). Catalposide also inhibited the expressions of TNF-alpha, IL-1beta, and IL-6 genes and the nuclear translocation of p65 subunit of NF-kappaB in LPS-activated RAW 264.7 cells. Flow cytometric analysis revealed that catalposide suppressed the binding of FITC-conjugated LPS to CD14 on the surface of cells, probably resulting in the inhibitory effects on TNF-alpha, IL-1beta, and IL-6 productions and NF-kappaB activation. These findings suggest that catalposide could be an attractive candidate for adjunctive therapy in gram-negative bacterial infections.

Ultrathin single-crystalline silver nanowire arrays formed in an ambient solution phase

We report the synthesis of single-crystalline silver nanowires of atomic dimensions. The ultrathin silver wires with 0.4 nanometer width grow up to micrometer-scale length inside the pores of self-assembled calix[4]hydroquinone nanotubes by electro-/photochemical redox reaction in an ambient aqueous phase. The present subnanowires are very stable under ambient air and aqueous environments, unlike previously reported metal wires of approximately 1 nanometer diameter, which existed only transiently in ultrahigh vacuum. The wires exist as coherently oriented three-dimensional arrays of ultrahigh density and thus could be used as model systems for investigating one-dimensional phenomena and as nanoconnectors for designing nanoelectronic devices.

Single cell analysis of CAG repeat in brains of dentatorubral-pallidoluysian atrophy (DRPLA)

Somatic mosaicism of an expanded repeat is present in tissues of patients with triplet repeat diseases. Of the spinocerebellar ataxias associated with triplet repeat expansion, the most prominent heterogeneity of the expanded repeat is seen in dentatorubral-pallidoluysian atrophy (DRPLA). The common feature of this somatic mosaicism is the difference in the repeat numbers found in the cerebellum as compared to other tissues. The expanded allele in the cerebellum shows a smaller degree of expansion. We previously showed by microdissection analysis that the expanded allele in the granular layer in DRPLA cerebellum has less expansion than expanded alleles in the molecular layer and white matter. Whether this feature of lesser expansion in granule cells is common to other types of neurons is yet to be clarified. We used a newly developed excimer laser microdissection system to analyze somatic mosaicism in the brains of two patients, one with early- and another with late-onset DRPLA, and used single cell PCR to observe the cell-to-cell differences in repeat numbers. In the late onset patient, repeat expansion was more prominent in Purkinje cells than in granule cells, but less than that in the glial cells. In the early onset patient, repeat expansion in Purkinje cells was greater than in granule cells but did not differ from that in glial cells. These findings suggest that there is a difference in repeat expansion among neuronal subgroups and that the number of cell division cycles is not the only determinant of somatic mosaicism.

cAMP enhances Cx43 gap junction formation and function and reverses choline deficiency apoptosis

Previously, it had been shown that acute choline deficiency (CD) induced apoptosis in cultured rat liver epithelial cells, whereas cells that are adapted to survive in low-choline-containing medium acquire resistance to CD apoptosis and undergo malignant transformation. Thus, understanding the mechanisms of action of CD could increase our understanding of the role of choline, an essential nutrient, in the process of malignant transformation. The present experiments were designed to test the hypothesis that CD might function as a pro-apoptotic trigger by altering the localization of connexin 43 gap junction protein and gap junctional intercellular communication (GJIC). Established liver epithelial cells (WB cells; Hep3B cells) were maintained in a defined, serum-free medium control (70 microM choline) or choline deficient medium (CD, 5 microM choline) and the localization of connexin 43 protein (Cx43) was studied by immunocytochemistry and Western blotting. In nontumorigenic WB cells, CD apoptosis was associated with retention of Cx43 in the golgi/ER region of the cytoplasm and decreased GJIC as measured using a preloading fluorescent dye transfer method (calcein AM/DiIC(18)). Cells maintained in CD in the presence of 8-bromoadenosine 3':5'-cyclic monophosphate exhibited restoration of Cx43 at the plasma membrane and increased GJIC and inhibition of apoptosis. These studies show that CD apoptosis in nontumorigenic liver epithelial cells is associated with alterations to Cx43 and GJIC and that an uncoupling of Cx43 localization and GJIC is related to resistance to CD apoptosis in transformed liver epithelial cells.

Tolerancing of diffraction-limited Kirkpatrick-Baez synchrotron beamline optics for extreme-ultraviolet metrology

The recent interest in extreme-ultraviolet (EUV) lithography has led to the development of an array of at-wavelength metrologies implemented on synchrotron beamlines. These beamlines commonly use Kirkpatrick-Baez (K-B) systems consisting of two perpendicular, elliptically bent mirrors in series. To achieve high-efficiency focusing into a small spot, unprecedented fabrication and assembly tolerance is required of these systems. Here we present a detailed error-budget analysis and develop a set of specifications for diffraction-limited performance for the K-B optic operating on the EUV interferometry beamline at Lawrence Berkeley National Laboratory's Advanced Light Source. The specifications are based on code v modeling tools developed explicitly for these optical systems. Although developed for one particular system, the alignment sensitivities presented here are relevant to K-B system designs in general.

Effect of an extract of the root of Scutellaria baicalensis and its flavonoids on aflatoxin B1 oxidizing cytochrome P450 enzymes

The inhibition of aflatoxin B1 (AFB1) metabolism by a water extract of the root of Scutellaria baicalensis and its flavonoids was examined in liver microsomes. AFB1 is known to be metabolized to aflatoxin M1 (AFM1), aflatoxin Q1 (AFQ1), and AFB1-8,9-epoxide (AFBO). The water extract potently inhibited the production of AFM1 by cytochrome P450 (CYP)1A1/2 and slightly reduced AFBO formation by CYP1A1/2, CYP2B1, CYP2C11 and CYP3A1/2 in TCDD-treated rat liver microsomes. IC50 values for AFM1 and AFBO formation were 6.8 and 122.4 microg/ml, respectively. Wogonin showed the highest inhibitory activity towards AFM1 formation among the flavonoids isolated from the extract. On the other hand, the extract had no effects on the formation of AFBO and AFQ1 in human liver microsomes, and on the activities of CYP2B1, CYP2C11 and CYP3A1/2 which were detected by hydroxylation patterns of testosterone. These results demonstrated that the extract of the root of Scutellaria baicalensis has a specific inhibitory effect on CYP1A1/2 among CYP enzymes involved in AFB1 metabolism by rat and human microsomes.

In vitro selection of RNA against kanamycin B

Aminoglycosides are well-known antibiotics that function by interacting with ribosomal RNA in bacteria. In order to understand the molecular details between RNA and the drug, RNA aptamer was selected against kanamycin B. After 12 cycles of selection, RNA was cloned and sequenced. Among 9 clones, sequences of three clones were identical, suggesting the selected RNA was enriched. Among the cloned RNA molecules, the triplicated RNA was the maximum binding RNA. It showed a 180 nM affinity (KD) to the cognate aminoglycoside, as measured by a surface plasmon resonance, and a competition assay using a fluorescence anisotropy technique. The affinity of the maximum binding RNA to a similar aminoglycoside, tobramycin, was much stronger than 12 nM of KD. The binding site of the aminoglycoside in the maximum binding RNA was a stem loop located at the end of the 5' region. A stem loop structural motif, found in this study, was similar to those previously reported, even though the sequences of the RNA were totally different from the known sequences of the aminoglycoside binding site of other aptamers. The present study suggests that the aminoglycoside-binding region in RNA does not have a sequence specificity, but has a shape-specific bulged stem loop, even though it has a nanomolar affinity.

Extreme-ultraviolet lensless Fourier-transform holography

We demonstrate 100-nm-resolution holographic aerial image monitoring based on lensless Fourier-transform holography at extreme-UV (EUV) wavelengths, using synchrotron-based illumination. This method can be used to monitor the coherent imaging performance of EUV lithographic optical systems. The system has been implemented in the EUV phase-shifting point-diffraction interferometer recently developed at Lawrence Berkeley National Laboratory. Here we introduce the idea of the holographic aerial image-recording technique and present imaging performance characterization results for a 10x Schwarzschild objective, a prototype EUV lithographic optic. The results are compared with simulations, and good agreement is obtained. Various object patterns, including phase-shift-enhanced patterns, have been studied. Finally, the application of the holographic aerial image-recording technique to EUV multilayer mask-blank defect characterization is discussed.

Atomic and electronic structures of N-incorporated Si oxides

We present first-principles total-energy calculations on the N-incorporated Si oxides, regarded as a replacement for conventional SiO2 in device technology. We investigate the energetics, charge states, and electronic structures for various bond configurations around N. While they remain in the N-incorporated structures, the charge trap states, responsible for leakage current in SiO2, are effectively removed from the energy gap in the H-terminated structures. This shows that improvement in the electrical reliabilities of Si oxynitride films is originated not from N incorporation itself, but from the coexistence of N and H.

In vitro selection of the RNA aptamer against the Sialyl Lewis X and its inhibition of the cell adhesion

Sialyl Lewis X (sLeX) is a tetra-saccharide glycoconjugate of membrane proteins. It acts as a ligand for the selectin proteins during cell adhesion of inflammatory process. Aberrant overexpression of sLeX is also a characteristic of various cancer cells, especially for highly malignant ones. In this paper, the sLeX-specific RNA aptamer was selected using a random RNA library and its affinity and specificity were measured by Surface Plasmon Resonance technique. Affinity of the selected RNA was increased about 1000-fold as compared with the original RNA pool. RNA aptamer bound more specifically to its cognate sugar than to any other similar sugars. Inhibition of the cell adhesion was also shown by in vitro static assay of sLeX-expressing HL60 cells to the E- and P-selectins. It suggests that the high affinity carbohydrate specific RNA aptamer could be used as an alternative to the antibody.

Effects of nicotine on APP secretion and Abeta- or CT(105)-induced toxicity

Several lines of evidence indicated that overexpression or aberrant processing of amyloid precursor protein (APP) is causally related to Alzheimer's disease (AD). Amyloid precursor protein is principally cleaved within the amyloid beta protein domain to release a large soluble ectodomain (APPs), known to have a wide range of trophic functions. The central hypothesis guiding this review is that nicotine may play an important role in APP secretion and protection against toxicity induced by APP metabolic fragments (beta-amyloid [Abeta], carboxyl terminal [CT]). Findings from our experiments have shown that nicotine enhances the release of APPs, which has neurotrophic and neuroprotective activities in concentration-dependent (>50 micromol/L) and time-dependent (>2 hours) manners. In addition, pretreatment of nicotine (>10 micromol/L for 24 hours) partially prevented Abeta or CT(105)-induced cytotoxicity in primary cultured neuron cells, and the effects of nicotine-induced protection were inhibited by the pretreatment with a nicotine alpha-bungarotoxin. Nicotine (>10 micromol/L for 24 hours) partially inhibited CT(105)-induced cytotoxicity when PC12 cells was transfected with CT(105). From these results, we proposed that nicotine or nicotinic receptor agonist treatment might improve the cognitive functions not only by supplementation of cholinergic neurotransmission, but also by protecting Abeta- or CT(105)-induced neurotoxicity probably through the increased release of APPs and the activation of nicotinic receptors.

A novel epigenetic control operating on Vme1+ locus leads to variegated monoallelic expression

Vme1, located near an imprinted region containing Peg1/Mest, Copg2, and Mit1/Lb9 on mouse chromosome 6, was identified and characterized to be under novel epigenetic regulations mediating nonimprinted monoallelic expression. The gene was transcribed independently from at least four promoters and alternatively spliced. Variable expression of the gene was found among individuals and was not affected by genetic backgrounds, in contrast to a relatively consistent expression of unlinked Peg3 under different genetic backgrounds. Monoallelic expression of the gene was confirmed in several tissues of hybrid F1s between a domesticus and a molossinus subspecies. The nature of monoallelic expression was different from those of its neighboring genes with respect to the allelic preference for the expression. The observed variable expression and monoallelic expression propose a mechanism that operates to variegate the Vme1 transcription acting asynchronously on parental alleles. In addition, we observed that some biallelically expressed tissues exhibited allele-specific splicing such that expression from one parental allele yields elongated splice variants, whereas the other allele is spliced into a short version. This unusual finding suggests that an epigenotype of the promoter can determine the splicing fate of the transcript.