Importance of early appropriate intervention including antibiotics and wound care for device-related infection in patients with left ventricular assist device.

INTRODUCTION: A left ventricular assist device (LVAD) is essential for treating patients with advanced heart failure. However, LVAD-related infection is a significant cause of mortality and morbidity, with bloodstream infection (BSI) especially associated with high mortality. We investigated the incidence of infectious complications in patients who received an LVAD and evaluated the effects of early and appropriate intervention for LVAD-related infection. METHOD: We retrospectively reviewed 27 consecutive patients who underwent continuous-flow LVAD (CF-LVAD; n = 16) or pulsatile-flow LVAD (PF-LVAD; n = 11) implantation at the National Cerebral and Cardiovascular Center between April 2011 and March 2013. Incidences of LVAD-related infections, such as drive-line infection in patients with CF-LVAD, cannula infection in patients with PF-LVAD, and BSI in patients with both types, were examined (follow-up period, 342 ± 229 days). The mandatory antibiotic prophylaxis protocol at our institution includes teicoplanin (400 mg) 2 days before LVAD implantation and doripenem (1000 mg) within 1 hour of skin incision. In addition, the driveline exit sites undergo sterile cleansing with diluted hydrogen peroxide and placement of an antimicrobial occlusive dressing for wound care, with dressing changes performed 2-3 times per day. RESULTS: More than 90% of all patients suffered from a drive-line infection within 12 months after LVAD implantation. However, BSI developed in only 12.5% of CF-LVAD and 10% of PF-LVAD patients within 12 months (log-rank test; P = .875). CONCLUSIONS: LVAD-related infections, such as drive-line and cannula infections, were common, whereas the incidence of BSI was low in our LVAD-implanted patients. Our results highlight the importance of early and appropriate intervention including antibiotics and wound care for device-related infections for reducing the incidence of potentially fatal BSI.

Endovascular therapy for massive haemothorax caused by ruptured extracranial vertebral artery aneurysm with neurofibromatosis Type 1.

Extracranial vertebral artery aneurysm is uncommon, and the common cause is penetrating trauma. Rupture of extracranial vertebral artery aneurysm into the thoracic cavity is extremely rare and fatal due to haemorrhagic shock by massive haemothorax. We report an intrathoracic rupture of the extracranial vertebral artery aneurysm with neurofibromatosis Type 1, successfully treated by coil and liquid embolisation.

Preoperative portal vein embolization with a mixture of gelatin sponge and iodized oil: efficacy and safety.

PURPOSE: To evaluate whether portal vein embolization (PVE) using a mixture of gelatin sponge (GS) pieces and iodized oil is safe and effective in inducing hypertrophy of the future liver remnants (FLR). MATERIAL AND METHODS: PVE was performed in 14 patients (eight male and six female, mean age 65 years, range 35-81 years) diagnosed with malignant liver tumor before surgery, whose FLR volumes were judged too small to allow for safe resection. Liver volume change, biochemical data change, complications related to PVE, and postoperative complications were retrospectively evaluated. RESULTS: PVE was successful in all patients, and there were no procedural complications. Absolute FLR volume and FLR/total liver volume (TLV) ratio increased by 102 cm3 and 8% (mean values), respectively. Planned hepatectomies were cancelled in three patients due to extrahepatic metastasis or bile duct infection. Five of the 11 patients (45%) who underwent hepatectomies had major postoperative complications. However, complications due to hepatic failure were not seen. In 10 patients, except one whose outcome was fatal outcome, the mean hospitalization days with and without major complications were 73 and 33 days, respectively. CONCLUSION: PVE using a mixture of GS and iodized oil seems to be effective and safe in inducing hypertrophy of the FLR.

Endovascular therapy for abdominal pseudoaneurysms: analysis from technical and clinical aspects.

PURPOSE: To clarify the factors of outcomes by endovascular therapy for abdominal pseudoaneurysm (PSA) from both technical and clinical aspects. MATERIAL AND METHODS: Sixteen patients with PSAs underwent embolization. Embolic methods were classified into two groups: proximal and distal embolization (PDE) and proximal embolization alone (PE). The patients were classified into four groups by shock index. Pre-embolization hemoglobin (Hb) level and decrease in Hb level were evaluated. Outcomes were classified into two groups: successful recovery and failure despite successful PSA embolization. RESULTS: There were no statistical differences in success, recurrence, and complication rate, and outcomes between the two embolic methods. There was a statistically significant correlation between the grades of shock indices and outcomes (P<0.05). There was no statistical difference between the Hb levels and outcomes. CONCLUSION: Outcomes were not dependent on the embolic methods. Shock index reflecting clinical status may be a simple predictor of outcome. PSA should therefore be treated by optimal embolic methods as quickly as possible to avoid rupture.

Nuclear import of the U1A splicesome protein is mediated by importin alpha /beta and Ran in living mammalian cells.

U1A is a component of the uracil-rich small nuclear ribonucleoprotein. The molecular mechanism of nuclear import of U1A was investigated in vivo and in vitro. When recombinant deletion mutants of U1A are injected into the BHK21 cell cytoplasm, the nuclear localization signal (NLS) of U1A is found in the N-terminal half of the central domain (residues 100-144 in mouse U1A). In an in vitro assay, it was found that the U1A-NLS accumulated in only a portion of the nuclei in the absence of cytosolic extract. In contrast, the addition of importin alpha/beta and Ran induced the uniform nuclear accumulation of U1A-NLS in all cells. Furthermore, U1A was found to bind the C-terminal portion of importin alpha. In addition, the in vitro nuclear migration of full-length U1A was found to be exclusively dependent on importin alpha/beta and Ran. Moreover, in living cells, the full-length U1A accumulated in the nucleus in a Ran-dependent manner, and nuclear accumulation was inhibited by the importin beta binding domain of importin alpha. These results suggest that the nuclear import of U1A is mediated by at least two distinct pathways, an importin alpha/beta and Ran-dependent and an -independent pathway in permeabilized cells, and that the latter pathway may be suppressed in intact cells.

Slippage of nonsuperfluid helium films

We measured the mechanical response of 3He and 4He films on an oscillating substrate using an ultrasonic technique. Up to the coverage at which the fluid state appears at absolute zero, a part of the nonsuperfluid 3He and 4He films underwent slipping relative to the substrate at low temperatures. From the temperature dependence of the slippage, it was found that a thermally activated process plays an important role in the frictional force of this system.

Recycling of importin alpha from the nucleus is suppressed by loss of RCC1 function in living mammalian cells.

We previously reported that the nuclear import of substrates containing SV40 T antigen nuclear localization signal (NLS) was suppressed in a temperature-sensitive RCC1 mutant cell line, tsBN2, at nonpermissive temperature. Moreover, it was shown that import into wild type BHK21 cell-derived nuclei gradually decreased in heterokaryons between the tsBN2 and BHK21 cells, although the BHK21 nuclei retained wild type RCC1 and should contain RanGTP (Tachibana et al., 1994). In this study, it was found that in the heterokaryons cultured at non-permissive temperature, endogenous importin alpha was not detected immunocytochemically in the cytoplasm or BHK21 nuclei but only in the tsBN2 nuclei, suggesting that importin alpha cannot be exported from the RCC1-depleted nuclei. In fact, importin alpha microinjected into the nucleus of tsBN2 cells at non-permissive temperature remained in the nucleus. These results strongly support the hypothesis that the recycling of importin alpha from the nucleus requires nuclear RanGTP. Moreover, it was found that cytoplasmic injection of importin alpha restored the import of SV40 T-NLS substrates in the BHK21 nuclei but not the tsBN2 nuclei in the heterokaryons. This indicates that the decrease of importin alpha from the cytoplasm in the heterokaryons leads to a suppression of the efficiency of nuclear import of the T-NLS substrate and provides support for the view that nuclear RanGTP is essential for the nuclear entry of the substrates.

Urinary excretion of aquaporin-2 water channel differentiates psychogenic polydipsia from central diabetes insipidus.

The present study was undertaken to determine whether urinary excretion of aquaporin-2 (AQP-2) water channel under ad libitum water intake is of value to differentiate polyuria caused by psychogenic polydipsia from central diabetes insipidus. A 30-min urine collection was made at 0900 h in 3 groups of: 11 patients with central diabetes insipidus (22-68 yr old), 10 patients with psychogenic polydipsia (28-60 yr old), and 15 normal subjects (21-38 yr old). In the patients with central diabetes insipidus, the plasma arginine vasopressin level was low despite hyperosmolality, resulting in hypotonic urine. Urinary excretion of AQP-2 was 37 +/- 15 fmol/mg creatinine, a value one-fifth less than that in the normal subjects. In the patients with psychogenic polydipsia, plasma arginine vasopressin and urinary osmolality were as low as those in the patients with central diabetes insipidus. However, urinary excretion of AQP-2 of 187 +/- 45 fmol/mg creatinine was not decreased, and its excretion was equal to that in the normal subjects. These results indicate that urinary excretion of AQP-2, under ad libitum water drinking, participates in the differentiation of psychogenic polydipsia from central diabetes insipidus.

A monoclonal antibody to the COOH-terminal acidic portion of Ran inhibits both the recycling of Ran and nuclear protein import in living cells.

A small GTPase Ran is a key regulator for active nuclear transport. In immunoblotting analysis, a monoclonal antibody against recombinant human Ran, designated ARAN1, was found to recognize an epitope in the COOH-terminal domain of Ran. In a solution binding assay, ARAN1 recognized Ran when complexed with importin beta, transportin, and CAS, but not the Ran-GTP or the Ran-GDP alone, indicating that the COOH-terminal domain of Ran is exposed via its interaction with importin beta-related proteins. In addition, ARAN1 suppressed the binding of RanBP1 to the Ran-importin beta complex. When injected into the nucleus of BHK cells, ARAN1 was rapidly exported to the cytoplasm, indicating that the Ran-importin beta-related protein complex is exported as a complex from the nucleus to the cytoplasm in living cells. Moreover, ARAN1, when injected into the cultured cells induces the accumulation of endogenous Ran in the cytoplasm and prevents the nuclear import of SV-40 T-antigen nuclear localization signal substrates. From these findings, we propose that the binding of RanBP1 to the Ran-importin beta complex is required for the dissociation of the complex in the cytoplasm and that the released Ran is recycled to the nucleus, which is essential for the nuclear protein transport.

Up-regulation of nuclear protein import by nuclear localization signal sequences in living cells.

Using an in vivo assay system, nuclear import ability in individual cells was determined by examining the nuclear import rate. It was found that when a small (not excess) amount of SV40 T-NLS peptides was co-injected, the nuclear import rate of SV40 T-NLS-containing substrates apparently increased. This up-regulation was reproduced by the co-injection of peptides containing bipartite type NLS of CBP80, but not mutated non-functional NLS peptides, which suggests that these phenomena are specific for functional NLSs. It was further shown that although, in growth-arrested cells, the nuclear import rate was down-regulated compared to growing cells, the elevation of the functional import rate by co-injected NLS peptides reached the same level as in proliferating cells. This up-regulation was abolished by the addition of a protein kinase inhibitor, staurosporine. These results suggest that although potential nuclear import ability does not vary in each cell, the rate of nuclear import may be controlled by the amount of karyophilic proteins, which need to be carried into the nucleus from the cytoplasm, possibly via an NLS-dependent phosphorylation reaction.

Nucleocytoplasmic protein transport and recycling of Ran.

The active transport of proteins into and out of the nucleus is mediated by specific signals, the nuclear localization signal (NLS) and nuclear export signal (NES), respectively. The best characterized NLS is that of the SV40 large T antigen, which contains a cluster of basic amino acids. The NESs were first identified in the protein kinase inhibitor (PKI) and HIV Rev protein, which are rich in leucine residues. The SV40 T-NLS containing transport substrates are carried into the nucleus by an importin alpha/beta heterodimer. Importin alpha recognizes the NLS and acts as an adapter between the NLS and importin beta, whereas importin beta interacts with importin alpha bound to the NLS, and acts as a carrier of the NLS/importin alpha/beta trimer. It is generally thought that importin alpha and beta are part of a large protein family. The leucine rich NES-containing proteins are exported from the nucleus by one of the importin beta family molecules, CRM1/exportin 1. A Ras-like small GTPase Ran plays a crucial role in both import/export pathways and determines the directionality of nuclear transport. It has recently been demonstrated in living cells that Ran actually shuttles between the nucleus and the cytoplasm and that the recycling of Ran is essential for the nuclear transport. Furthermore, it has been shown that nuclear transport factor 2 (NTF2) mediates the nuclear import of RanGDP. This review largely focuses on the issue concerning the functional divergence of importin alpha family molecules and the role of Ran in nucleocytoplasmic protein transport.

Molecular cloning and functional analysis of cynomolgus monkey CYP1A2.

Complementary DNA fragments encoding cynomolgus monkey CYP1A2 were amplified by the reverse transcriptase-polymerase chain reaction (RT-PCR) method from the liver total RNA of a 3-methylcholanthrene (3-MC)-treated cynomolgus monkey. The nucleotide sequence determined was 1630 bp long and contained an open reading frame for a polypeptide of 516 residues. The nucleotide and the deduced amino acid sequences of cynomolgus monkey CYP1A2 showed 95.1 and 92.8% identities to those of human CYP1A2, respectively. The level of CYP1A2 mRNA in the liver of untreated cynomolgus monkey was very low. Treatment with 3-MC increased it. Still, it was one-fortieth that of CYP1A1. Cynomolgus monkey CYP1A2 expressed in recombinant yeasts activated 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-3,8dimethylimidazo[4,5-flquinoxaline (MeIQx) at efficient rates in the umu mutagenicity test. This cytochrome P450 (CYP) also activated 2-amino-l-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), but less efficiently. These results indicate that cynomolgus monkeys have a functionally active CYPIA2 gene, but its expression level is very low in the liver of untreated cynomolgus monkeys.

Marmoset CYP1A2: primary structure and constitutive expression in livers.

Complementary DNA of marmoset CYP1A2 was isolated by means of screening the cDNA library and reverse-transcriptase polymerase chain reaction. The deduced amino acid sequence of marmoset CYP1A2 consisted of 516 residues and showed 88.2 and 90.0% identities to corresponding forms in human and cynomolgus monkey, respectively. S1 nuclease protection assay demonstrated that CYP1A2 mRNA was expressed constitutively in the liver, but not in the lung, kidney and small intestine. The level of CYP1A2 mRNA in the liver was increased by treatment with 3-methylcholanthrene and polychlorinated biphenyls. Marmoset CYP1A2 expressed in recombinant yeast activated 2-amino-3-methylimidazo [4,5-f]quinoline (IQ) and 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx) efficiently, and also activated 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP), but at a relatively lower rate in the umu mutagenicity test. Marmoset CYP1A2 also showed ethoxyresorufin O-de-ethylase activity. Based on these results, we demonstrate that marmosets constitutively express CYP1A2 in the liver as in humans.

Exogenously injected nuclear import factor p10/NTF2 inhibits signal-mediated nuclear import and export of proteins in living cells.

p10/NTF2 is a cytosolic factor which is required for the translocation step in nuclear protein import in an in vitro assay with digitonin-permeabilized cells. To study the functional roles of p10/NTF2 on protein transport between the nucleus and cytoplasm in living cells, recombinant p10/NTF2 was micro-injected into cultured mammalian cells. Cytoplasmically injected p10/NTF2 strongly inhibited the nuclear import of co-injected NLS-containing substrates in a dose-dependent manner but had no effect on the diffusive import of small non-nuclear proteins. Moreover, when injected into the cell nucleus, p10/NTF2 inhibited the nuclear export of NES-containing substrates. The results suggest that the nuclear import factor p10/NTF2 may also be involved in the nuclear export of proteins and that the protein transport efficiency between the nucleus and cytoplasm may be regulated by the intracellular level of p10/NTF2.

[Magnetic resonance studies of dentato-rubro-pallido-luysian atrophy--correlation with clinical severity and age of onset].

Dentato-rubro-pallido-luysian atrophy (DRP-LA) is a rare autosomal dominant neurodegenerative disorder. Recently the genetic abnormality has become clear. We encountered four patients with DRPLA (including a 14-year-old boy and his father) in whom the final diagnosis was made by DNA analysis. In addition to performing conventional MRI, we quantified brain metabolites by proton MR spectroscopy. We also compared the expanded repeat size of CAG trinucleotide in a gene on the short arm of chromosome 12 to the MR findings which consisted of the findings of clinical severity and age of onset. The method reported by Nagafuchi et al. was used to determine the size of the CAG repeat on the focus chromosome. Repeat size was closely correlated with age at onset and disease severity. The MR studies were performed with a Magnetum H-15SP (Siemens, 1.5 Tesla) equipped with a C-P type head coil. Axial T2-WIs (TR = 2000 ms, TE = 90 ms) and T1-WIs (TR = 200 ms, TE = 15 ms) were measured. Atrophy of the brainstem, the tegmentum, and the cerebellum, and periventricular hyperintensity could be seen. The sequence for 1H-MRS was PRESS, voxel size was 8 ml, and regions of interest were placed on right basal ganglia and right parietal white matter. After compensating the observed signals, we obtained metabolite concentrations by using compensated water intensity as an internal standard. Despite the absence of abnormalities of the basal ganglia on MRI, NAA concentrations differed from patient to patient and were low in severe clinical cases. We propose that the CAG repeat size of the focus chromosome and NAA concentration quantified by 1H-MRS are closely correlated with clinical severity and age of onset. In conclusion, DNA analysis may be useful in early diagnosis and 1H-MRS can detect metabolic abnormalities non-invasively even when no markedly abnormal findings can be detected with other clinical modalities.

[Interference of antibody reaction with porcine pancreatic amylase in enzymatic assay of total calcium].

Unreliable results were obtained in an enzymatic assay of total calcium (Ca) in a patient's serum using porcine pancreatic amylase (PPA). Besides, the result was different from that obtained by the atomic absorption analysis. Fractionation of the patient's serum by ultrafiltration and Sephadex G-200 gel filtration revealed the presence of an interference substance with a large molecular size of more than 200kDa. This interference substance was absorbed on a Protein A column. Furthermore, an immune precipitate was observed between the patient's serum and PPA by Ouchterlony double immunodiffusion. An antibody against PPA may exist in the patient's serum and interfere with the enzymatic assay of Ca using PPA.

[A correlation between the function and the aspiration cytology in chronic thyroiditis (author's transl)].

The correlation between the function and the aspiration cytology in chronic thyroiditis was studied. In 184 cases of chronic thyroiditis (hyperthyroid state: 19 cases, euthyroid state: 113 cases, hypothyroid state: 52 cases) and 36 cases of hyperthyroidism, aspiration biopsy was performed by a fine needle of 22 gauge. The smears were stained with May-Grünwald-Giemsa and Papanicolaou's stain. In all specimens, the cytological investigations were done as for follicular epithelial cells, oxyphilic changes of follicular epithelial cells and non-epithelial cells, oxyphilic changes of follicular epithelial cells and non-epithelial cells per se. The relationships between the thyroid function and cytological pictures in chronic thyroiditis were studied. The following conclusions were obtained by this study: 1. Compared to hyperthyroidism, chronic thyroiditis has the following characteristic cytological picture: i) Hyperplasia of small follicular cells with many lymphoid cells ii) Oxyphilic changes in follicular cells, lymphoid cells, plasma cells and reticulum cells 2. As for the correlation between the cytological findings and the thyroid function or thyroid antibodies, the following conclusions were obtained: i) There is a negative correlation between the grade of the number of oxyphilic cells or lymphocytes and the titer of the microsome test (MCHA). (p less than 0.005)