An ionic polymer bead-supported lipid system

In this paper, we report on the preparation of an ionic polymer bead-supported lipid system several hundred micrometers in diameter. The electrostatic attractive interactions between anionic lipids and cationic polymer beads served as a "molecular glue" to immobilize the lipids on the beads, and then the immobilized lipids prompted the spontaneous formation of lipid bilayer membranes. Confocal fluorescence microscopic techniques revealed that the lipid bilayer membranes were located along the outline of the beads. In addition, the integrity of the lipid bilayer membranes was microscopically confirmed by a low-molecular-weight dye (trypan blue) exclusion test.

Nucleus accumbens nitric oxide immunoreactive interneurons receive nitric oxide and ventral subicular afferents in rats

The nitric oxide generating neurons of the nucleus accumbens exert a powerful influence over striatal function, in addition, these nitrergic inputs are in a position to regulate the dopaminergic and glutamatergic inputs on striatal projection neurons. It was the aim of this study to establish the source of the glutamatergic drive to nitric oxide synthase interneurons of the nucleus accumbens. The nucleus accumbens nitric oxide-generating neurons receive asymmetrical, excitatory, presumably glutamatergic inputs. Possible sources of these inputs could be the limbic and cortical regions known to project to this area. To identify sources of the excitatory inputs to the nitric oxide synthase-containing interneurons of the nucleus accumbens in the rat we first examined the ultrastructural morphology of asymmetrical synaptic specializations contacting nitric oxide synthase-immunohistochemically labeled interneurons in the nucleus accumbens. Neurons were selected from different regions of the nucleus accumbens, drawn using camera lucida, processed for electron microscopic analysis, and the boutons contacting nitric oxide synthase-labeled dendrites were photographed and correlated to the drawings. Using vesicle size as the criterion the source was predicted to be either the prefrontal cortex or the ventral subiculum of the hippocampus. To examine this prediction, a further study used anterograde tracing from both the prefrontal cortex and the ventral subiculum, and nitric oxide synthase immunohistochemistry with correlated light and electron microscopy. Based on appositions by anterogradely labeled fibers, selected nitric oxide synthase-labeled neurons within the nucleus accumbens, were examined with electron microscopic analysis. With this technique we confirmed the prediction that subicular afferent boutons make synaptic contact with nitric oxide synthase interneurons, and demonstrated anatomically that nitric oxide synthase boutons make synaptic contact with the dendritic arbors of nitric oxide synthase interneurons. We suggest that the subicular input may excite the nitric oxide synthase neurons synaptically, while the nitric oxide synthase-nitric oxide synthase interactions underlie a nitric oxide signaling network which propagates hippocampal information, and expands the hippocampus's influence on 'gating' information flow across the nucleus accumbens.

PIGEA-14, a Novel Coiled-coil Protein Affecting the Intracellular Distribution of Polycystin-2

Employing a yeast two-hybrid screen with the COOH terminus of polycystin-2, one of the proteins mutated in patients with polycystic kidney disease, we were able to isolate a novel protein that we call PIGEA-14 (polycystin-2 interactor, Golgi- and endoplasmic reticulum-associated protein with a molecular mass of 14 kDa). Molecular modeling only predicts a coiled-coil motif, but no other functional domains, in PIGEA-14. In a subsequent two-hybrid screen using PIGEA-14 as a bait, we found GM130, a component of the cis-compartment of the Golgi apparatus. Co-expression of the PIGEA-14 and PKD2 cDNAs in LLC-PK(1) and HeLa cells resulted in a redistribution of PIGEA-14 and polycystin-2 to the trans-Golgi network, which suggests that PIGEA-14 plays an important role in regulating the intracellular location of polycystin-2 and possibly other intracellular proteins. Our results also indicate that the intracellular trafficking of polycystin-2 is regulated both at the level of the endo-plasmic reticulum and that of the trans-Golgi network.

Platelet-derived endothelial cell growth factor expression is an independent prognostic factor in colorectal cancer patients after curative surgery

AIMS

Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor that undergoes increased expression in colorectal carcinomas, but its prognostic value is a topic of debate. The aim of this study is to clarify the prognostic value of PD-ECGF expression in colorectal carcinomas.

METHODS

PD-ECGF expression was measured by enzyme-linked immunosorbent assay in frozen materials from 134 colorectal cancer patients who had received curative resections. Patients were divided into high expression and low expression groups based upon selected cut-off value. Correlations among PD-ECGF expression, clinicopathologic features, and disease-free interval were studied by univariate and multivariate analysis. To evaluate the origin of PD-ECGF, serial sections of the 134 tumours were stained for PD-ECGF and CD68.

RESULTS

PD-ECGF expression in the normal mucosa was 34.4+/-15.5 (Units/mg protein) and the cut-off value was 65.4 (mean+2SD). There were no significant correlations between clinicopathological features and PD-ECGF expression. The disease-free interval for the high PD-ECGF expression group was significantly longer than that of the low expression group (P=0.05). A multivariate Cox's regression analysis revealed that high PD-ECGF expression is an independent factor for better outcome. In immunohistochemical study, almost all tumour cells were negative for PD-ECGF, but stromal macrophages were predominantly positive for PD-ECGF.

CONCLUSIONS

The PD-ECGF expression originated from stromal macrophages was a predictor for favorable outcome after curative resections for colorectal cancer.

Modified CLIP using PIVKA-II for evaluating prognosis after hepatectomy for hepatocellular carcinoma

AIMS

The new staging system proposed by the Cancer of the Liver Italian Program (CLIP) for hepatocellular carcinoma (HCC) accounts for both liver dysfunction and tumour characteristics. The present study was designed to analyze UICC TNM stage, CLIP and modified CLIP in 91 patients who underwent hepatic resection for HCC.

METHODS

In the modified CLIP, scoring of AFP was replaced by that of protein induced by vitamin K absence or antagonist II (PIVKA-II; predictive value, > or = 400 mAU/ml).

RESULTS

After hepatic resection, 54 patients developed recurrent tumours. High PIVKA-II was a significant determinant of recurrence (p<0.05). However, a high score of the modified CLIP as well as those other staging systems did not correlate with tumour-recurrence rate. Univariate analysis showed that high TNM score, CLIP score and our modified CLIP score were significant predictors of poor prognosis. Multivariate Cox's analysis revealed that high PIVKA-II and high modified CLIP score were associated with higher risk for disease-free and overall survival as well as high TNM stage.

CONCLUSIONS

Compared with the original CLIP, our modified CLIP was a better predictor of prognosis of HCC patients who underwent hepatic resection.

Leptin as an adjunct of insulin therapy in insulin-deficient diabetes

AIMS/HYPOTHESIS

The purpose of this study was to assess the therapeutic implication of leptin in insulin-deficient diabetes.

METHODS

Insulin-deficient diabetes was induced by streptozotocin (STZ) in transgenic skinny mice overexpressing leptin. Plasma concentrations of glucose, insulin, and leptin were measured. The effects on body weight, food intake, and hypothalamic gene expressions were analyzed. After diabetes was induced, graded doses of insulin ranging from 0.4 to 51.2 mU.g(-1).day(-1) were injected. Co-administration of leptin and insulin was also carried out using osmotic pumps.

RESULTS

After STZ injection, both transgenic and non-transgenic littermates developed marked hyperglycaemia as a result of severe hypoinsulinaemia [termed diabetic transgenic skinny mice overexpressing leptin (diabetic TGM) and diabetic non-transgenic littermates (diabetic WT) respectively], although diabetic TGM were more sensitive to exogenously administered insulin than diabetic WT. Diabetic WT were hypoleptinaemic and hyperphagic relative to non-diabetic WT, whereas diabetic TGM, which remained hyperleptinaemic, were less hyperphagic than diabetic WT. After STZ injection, hypothalamic expressions of orexigenic and anorexigenic peptide mRNAs were up-regulated and down-regulated, respectively, in diabetic WT, whereas they were unchanged in diabetic TGM. Diabetic TGM became normoglycaemic, when treated with insulin at such doses that did not improve hyperglycaemia in diabetic WT. We found that a sub-threshold dose of insulin that does not affect glucose homeostasis is effective in improving the diabetes in normal mice rendered diabetic by STZ injection, when combined with leptin.

CONCLUSIONS/INTERPRETATION

This study suggests that leptin could be used as an adjunct of insulin therapy in insulin-deficient diabetes, thereby providing an insight into the therapeutic implication of leptin as an anti-diabetic agent.

Characterization of the small subgenomic RNA of Soybean dwarf virus

We have characterized a small subgenomic RNA of Japanese strains of Soybean dwarf virus (SbDV). Northern blot analyses of SbDV-infected plants showed that the small RNA contained the 3' terminal sequence of the genome and was detected in four typical Japanese SbDV strains, YS, YP, DS and DP. In the case of SbDV-DS, the RNA was 220 nucleotides in length and was transcribed from the 3' terminal region of the genome. This RNA appeared at a similar time to genomic RNA and a large sgRNA, and thereafter persisted in the infected plant. Since no conserved open reading frame (ORF) among the strains was postulated in the 3' terminal region, the small subgenomic RNA may have some regulatory roles in SbDV infections.

Chromosomal imbalances associated with acquired resistance to fluoropyrimidines in human colorectal cancer cells

The chromosomal aberrations underlying the development of resistance to fluoropyrimidines have not yet been identified. To characterise the genomic changes that induce the development of resistance to fluoropyrimidines, we used comparative genomic hybridisation (CGH) to analyse and compare the parent DLD-1 human colorectal cancer cell line and two cell lines, DLD-1/5-FU and DLD-1/FdUrd, which were resistant to 5-fluorouracil (5-FU) and 5-fluoro-2'-deoxyuridine (FdUrd), respectively. Both resistant cell lines showed a genetic aberration derived from the parental cell line DLD-1. Losses of 3p and 3q were also detected as additional genetic changes in the two resistant cell lines. Both resistant cell lines showed decreased orotate phosphoribosyltransferase (OPRT) activity, which is associated with the activity of the uridine monophosphate (UMP) synthase gene (3q13). These results suggested that the loss of 3q might be a genetic change responsible for the decreased OPRT activity and fluoropyrimidine cytotoxic response in cancer cells. Amplification of 18p11.2-p11.3 containing the thymidine synthase (TS) gene (18p11.32) was observed only in the DLD-1/FdUrd-resistant cell line, which overexpresses TS. These findings suggested that 18p amplification represents a genetic change associated with the overexpression of the TS protein. Our results indicate that chromosomal aberrations identified by CGH could explain, at least in part, acquired fluoropyrimidine resistance.

Urinary clusterin levels in the rat correlate with the severity of tubular damage and may help to differentiate between glomerular and tubular injuries

Clusterin is a secreted glycoprotein that is synthesized after several types of tubular injury. We therefore wondered whether the urinary excretion of clusterin could serve as a parameter to determine the severity of tubular damage. Using an affinity-purified rabbit antiserum raised against recombinant clusterin, we established an enzyme-linked immunosorbent assay to measure the urinary excretion of clusterin after bilateral renal ischemia, in the (cy/ +) rat model of autosomal-dominant polycystic kidney disease and in the FHH rat model of focal segmental glomerulosclerosis. After bilateral renal ischemia, the urinary excretion of clusterin paralleled the excretion of total protein and albumin and correlated with the extent of tubular damage. Male (cy/ +) rats, but not female (cy/ +) rats, excreted more clusterin than age-matched (+/ +) rats, a finding consistent with the more rapid course of the disease in males. FHH rats presented with pronounced proteinuria and albuminuria but did not excrete increased levels of clusterin. Urinary clusterin levels could therefore serve as a valuable marker for the severity of tubular damage. Furthermore, clusterin may also help to differentiate between tubular and glomerular forms of proteinuria.

Search for the KL-->pi 0 pi 0 e+e- decay in the KTeV experiment

The recent discovery of a large CP violating asymmetry in KL-->pi+pi-e+e- mode has prompted us to seach for the associated KL-->pi 0 pi 0 e+e- decay mode in the KTeV-E799 experiment at Fermilab. In 2.7 x 10(11) K(L) decays, one candidate event has been observed with an expected background of 0.3 event, resulting in an upper limit for the KL-->pi 0 pi 0 e+e- branching ratio of 6.6 x 10(-9) at the 90% C.L.

[A case of fulminant acute poststreptococcal glomerulonephritis showing mesangiolysis and crescent formation preceded by erysipelas]

A 66-year-old man with erysipelas was admitted with complaints of oliguria and massive proteinuria/hematuria. He was diagnosed as having acute poststreptococcal glomerulonephritis(APSGN) due to erysipelas infected by group A streptococcus pyogenes. On admission, his white cell count increased to 31,000, and CRP was 27.3 mg/dl. Serum urea nitrogen and creatinine were increased to 90.1 mg/dl and 4.5 mg/dl, respectively. He had diabetes mellitus(HbA1c 7.9%) and liver dysfunction(total bilirubin 3.5 mg/dl, AST 76 IU, ALT 41 IU) caused by alcoholic liver cirrhosis. Hypocomplementemia was found in addition to ASO 216 U/ml and ASK 10,240 x. After antibiotics treatment was initiated, inflammation of the erysipelas began to improve. Disseminated intravascular coagulation syndrome, probably due to sepsis, occurred on the 5th hospital day. He died of gastrointestinal bleeding on the 18th hospital day. Renal autopsy revealed 37% formation of fibrocellular crescents, and marked mesangiolysis was noted by light microscopy. Granular deposition of C3 and IgG was seen along the capillary walls on immunofluorescence study. Intramembranous deposits were scattered on electron microscopy. This case illustrates a fulminant type of APSGN, which was in part attributed to the presence of diabetes and alcoholic liver cirrhosis. Histological findings of crescent formation and marked mesangiolysis may account for the fulminant clinical course.

Radiative decay width measurements of neutral kaon excitations using the primakoff effect

We use K(L)'s in the 100-200 GeV energy range to produce 147 candidate events of the axial vector pair K1(1270)-K1(1400) in the nuclear Coulomb field of a Pb target and determine the radiative widths Gamma(K1(1400)-->K0+gamma)=280.8+/-23.2(stat)+/-40.4(syst) keV and Gamma(K1(1270)-->K0+gamma)=73.2+/-6.1(stat)+/-28.3(syst) keV. These first measurements appear to be lower than the quark-model predictions. We also place upper limits on the radiative widths for K(*)(1410) and K(*)(2)(1430) and find that the latter is vanishingly small in accord with SU(3) invariance in the naive quark model.

Measurement of the K(L) charge asymmetry

We present a measurement of the charge asymmetry delta(L) in the mode K(L)-->pi(+/-)e(-/+)nu based on 298 x 10(6) analyzed decays. We measure a value of delta(L) = [3322+/-58(stat)+/-47(syst)]x10(-6), in good agreement with previous measurements and 2.4 times more precise than the current best published result. The result is used to place more stringent limits on CPT and DeltaS = DeltaQ violation in the neutral kaon system.

Heart rate to arterial pressure impulse response during one lung ventilation

BACKGROUND

Although one lung ventilation (OLV) is commonly used, little is known about the modulation of the autonomic nervous system with OLV while under general anesthesia. As the frequency domain and time domain analyses are powerful analytic tools, we investigated their modulation during OLV.

METHODS

Patients undergoing thoracic surgery were classified into two groups: those who did (group A, n=8) and those who did not (group N, n=8) receive atropine. After a double lumen tube was placed endotracheally, mechanical ventilation of both lungs (BLV) was established at 18 min(-1) while under isoflurane anesthesia. Electrocardiogram, systolic arterial pressure (SAP), and inspiratory flow (Finsp) were digitally recorded as follows: awake before anesthesia; BLV after anesthesia; BLV after intravenous 10 microg kg(-1) of atropine (group A) or not (group N); left OLV; and right OLV. Power spectral analyses of heart rate (HR) and SAP were computed by determining low-(LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0.40 Hz) components, and impulse response analysis was executed among HR, SAP, and Finsp. Impulse responses were assessed by the maximum values in the time domain.

RESULTS

In frequency domain analysis, atropine depressed LF and LF/HF but not HF in HR variability, while no difference was observed between right OLV and left OLV. The heart rate to SAP impulse response was maintained at a significantly higher level in group A than in group N (905+/-360 vs. 425+/-375 mmHg beats(-1)min(-1)) at right OLV. A significant difference was also observed between left and right OLV within group N.

CONCLUSION

Impulse response analysis demonstrated that there is a greater effect on autonomic nervous system modulation during right OLV than in left OLV, which mainly results from a parasympathetic neural linkage origin.

Alterations of ubiquitin immunoreactivity in the hippocampal formation after perforant pathway lesion

Immunohistochemical techniques were employed to examine the changes in free ubiquitin within the hippocampus 1, 3, 7, 14, and 30 days after a unilateral perforant pathway lesion occurred in the rat brain. Immunoreactivity for ubiquitin was remarkably decreased in the cell body and proximal dendrites of neurons throughout the hippocampus ipsilateral to the lesion at 1 day post-lesion. At 3 days post-lesion, ubiquitin immunoreactivity was recovered in interneurons in the whole hippocampus as well as in mossy cells in the hilar region, although granule cells in the dentate gyrus and pyramidal cells in the CA1 subfield remained unlabeled, and pyramidal cells in the CA3 subfield demonstrated only weak immunoreactivity. In addition, we observed an increase in ubiquitin immunolabeling of the hilar neuropil ipsilateral to the lesion at 1 and 3 days post-lesion, and a decrease in immunolabeling in the inner portion of the molecular layer at 3 days post-lesion. All these alterations were transient, and by 7 days post-lesion, ubiquitin immunoreactivity was indistinguishable in the hippocampus ipsilateral to the lesion, compared to the controls. Immunoblot analysis also revealed a decrease in the amount of ubiquitin in the hippocampus ipsilateral to the lesion 1 and 3 days post-lesion. These data suggest that deafferentation of the perforant pathway results in transient reduction in free ubiquitin of the hippocampus, and that the ubiquitin system is involved in hippocampal plasticity following perforant lesions.

Molecular basis of autosomal-dominant polycystic kidney disease

Autosomal-dominant polycystic kidney disease (ADPKD) is one of the most common monogenetic diseases in humans. The discovery that mutations in the PKD1 and PKD2 genes are responsible for ADPKD has sparked extensive research efforts into the physiological and pathogenetic role of polycystin-1 and polycystin-2, the proteins encoded by these two genes. While polycystin-1 may mediate the contact among cells or between cells and the extracellular matrix, a lot of evidence suggests that polycystin-2 represents an endoplasmic reticulum-bound cation channel. Cyst development has been compared to the growth of benign tumors and this view is highlighted by the model that a somatic mutation in addition to the germline mutation is responsible for cystogenesis (two-hit model of cyst formation). Since in vitro polycystin-1 and polycystin-2 interact through their COOH termini, the two proteins possibly act in a common pathway, which controls the width of renal tubules. The loss of one protein may lead to a disruption of this pathway and to the uncontrolled expansion of tubules. Our increasing knowledge of the molecular events in ADPKD has also started to be useful in designing novel diagnostic and therapeutic strategies.

Hypoleptinemia, but not hypoinsulinemia, induces hyperphagia in streptozotocin-induced diabetic rats

To assess the dominance between hypoinsulinemia and hypoleptinemia as factors in the development of hyperphagia in streptozotocin (STZ)-induced diabetes mellitus (STZ-DM) rodents with respect to hormone-neuropeptide interactions, changes in gene expression of agouti gene-related protein (AGRP) in the arcuate nucleus of the hypothalamus were investigated using STZ-DM rats, fasting Zucker fa/fa rats and STZ-DM agouti (STZ-DM A(y)/a) mice. AGRP mRNA and neuropeptide Y mRNA were both significantly up-regulated in STZ-DM rats, which are associated with body weight loss, hyperglycemia, hypoinsulinemia and hypoleptinemia. We proceeded to analyze whether insulin or leptin played the greater role in the regulation of AGRP using Zucker fa/fa rats. The AGRP mRNA did not differ significantly between fasted fa/fa rats, which have both leptin-insensitivity and hypoinsulinemia, and fed Zuckers, which have leptin-insensitivity and hyperinsulinemia. We further found that up-regulation of AGRP expression was normalized by infusion of leptin into the third cerebroventricle (i3vt), but not by i3vt infusion of insulin, although up-regulation of AGRP was partially corrected by systemic insulin infusion. The latter finding supports hypoleptinemia as a key-modulator of STZ-DM-induced hyperphagia because systemic insulin infusion, at least partially, restored hypoleptinemia through its acceleration of fat deposition, as demonstrated by the partial recovery of lost body weight. After STZ-DM induction, A(y)/a mice whose melanocortin-4 receptor (MC4-R) was blocked by ectopic expression of agouti protein additionally accelerated hyperphagia and up-regulated AGRP mRNA, implying that the mechanism is triggered by a leptin deficit rather than by the main action of the message through MC4-R. Hypoleptinemia, but not hypoinsulinemia per se, thus develops hyperphagia in STZ-DM rodents. These results are very much in line with evidence that hypothalamic neuropeptides are potently regulated by leptin as downstream targets of its actions.

[Potential molecular targets for anti-obesity drugs--after the discovery of leptin]

The discovery of the adipose-derived hormone leptin has generated interest in the interaction between peripheral signals and brain targets involved in the regulation of feedings and energy balance. Potential anti-obesity drugs can be based on any intervention between the neuropeptide and its receptor that would alter the biological responses mediated by the neuronal network, in particular, food intake, metabolism and energy expenditure. Modulation of neurons in the arcuate nucleus by leptin results in reduced expression of neuropeptide Y and agouti-related protein, and increased expression of pro-opiomelanocortin (the precursor of a-melanocyte-stimulating hormone) and cocaine- and amphetamine- regulated transcript. Whether leptin finds its way into general usage as an anti-obesity drug, the use of modern methods to identify and target the components of leptin signaling pathway will form the basis for new pharmacological approaches to the treatment of obesity.

Comparison of complete nucleotide sequences of genomic RNAs of four Soybean dwarf virus strains that differ in their vector specificity and symptom production

Soybean dwarf virus (SbDV) is divided into four strains, namely YS, YP, DS and DP. YS and YP cause yellowing in soybeans, while DS and DP cause dwarfing. YS and DS are transmitted by Aulacorthum solani, while YP and DP are transmitted by Acyrthosiphon pisum. To clarify the taxonomic relationship between the four strains and to classify SbDV into an appropriate genus in the Luteoviridae, we determined the complete nucleotide sequences of genomic RNAs of four isolates belonging to each of the strains. The genomes of the four isolates had a chimeric form between Barley yellow dwarf virus-PAV and poleroviruses, and the genome organizations were similar to the Australian isolate SbDV Tas-1. In all of the non-coding regions and ORFs, nucleotide and deduced amino acid sequence identity between the same symptom-type strains was higher than that between the different symptom-type strains. However, in the N-terminal half of the readthrough domain (RTD) the deduced amino acid identity between the same aphid transmissibility-type strains was higher than that between the different aphid transmissibility-type strains. These data suggest that the N-terminal half of the RTD is closely related to the aphid transmission specificity, and that the present strains were generated from ancestral Y and D strains by mutations and strong selection pressures of efficient aphid transmission. Therefore, we propose that SbDV should be classified into a new genus in the family Luteoviridae and that the four strains described should be regarded as different strains of the same virus, rather than as distinct virus species.

First measurement of form factors of the decay Xi(0) --> Sigma(+)e(-)nu macro(e)

We present the first measurement of the form factor ratios g(1)/f(1) (direct axial vector to vector), g(2)/f(1) (second class current), and f(2)/f(1) (weak magnetism) for the decay Xi(0)-->Sigma(+)e(-)nu macro(e) using the KTeV (E799) beam line and detector at Fermilab. From the Sigma(+) polarization measured with the decay Sigma(+)-->p pi(0) and the e(-)-nu; correlation, we measure g(1)/f(1) to be 1.32+/-(0.21)(0.17)(stat)+/-0.05(syst), assuming the SU(3)(f) (flavor) values for g(2)/f(1) and f(2)/f(1). Our results are all consistent with exact SU(3)(f) symmetry.

Branching ratio measurement of the decay K(L) --> e(+)e(-)mu(+)mu(-)

We have collected a 43 event sample of the decay K(L)-->e(+)e(-)mu(+)mu(-) with negligible backgrounds and measured its branching ratio to be (2.62+/-0.40+/-0.17)x10(-9). We see no evidence for CP violation in this decay. In addition, we set the 90% confidence upper limit on the combined branching ratios for the lepton flavor violating decays K(L)-->e(+/-)e(+/-)mu(-/+)mu(-/+) at B(K(L)-->e(+/-)e(+/-)mu(-/+)mu(-/+))< or =1.23x10(-10), assuming a uniform phase space distribution.