Risk Factors for and Management of Postpancreatectomy Hepatic Steatosis.

BACKGROUND: Relatively little is known about the risk factors and treatments for postpancreatectomy hepatic steatosis. METHODS: The records of patients who underwent pancreaticoduodenectomy or total pancreatectomy between 2005 and 2010 and were followed up by periodic imaging were reviewed retrospectively. Risk factors and treatment for postpancreatectomy hepatic steatosis were analyzed. RESULTS: A total of 253 patients were included in the analysis, including 137 males and 116 females, of median (5, 95 percentile) age 67 (47, 81) years. Of these 253 patients, 75 (29.6%) developed postpancreatectomy hepatic steatosis. Multivariable logistic regression analysis showed that female gender ( p = 0.005; odds ratio: 2.387; 95% confidence interval: 1.293-4.386), body mass index > 22.5 kg/m2 ( p = 0.007; odds ratio: 2.330; 95% confidence interval: 1.261-4.307), operative duration > 540 min ( p = 0.018; odds ratio: 2.286; 95% confidence interval: 1.153-4.533), and delayed gastric emptying ( p < 0.001; odds ratio: 4.598; 95% confidence interval: 1.979-10.678) were independent risk factors associated with postpancreatectomy hepatic steatosis. Treatment consisted of maintenance- or high-dose digestive enzyme replacement therapy. Of patients without obvious tumor recurrence after 6 months, 12 of 15 treated with high dose and only 6 of 35 treated with maintenance-dose digestive enzyme replacement therapy showed improvements in postpancreatectomy hepatic steatosis ( p = 0.006). CONCLUSION: Female gender, obesity, longer operative time, and occurrence of delayed gastric emptying are risk factors for postpancreatectomy hepatic steatosis. High-dose digestive enzyme replacement therapy may improve postpancreatectomy hepatic steatosis.

Femtosecond charge and molecular dynamics of I-containing organic molecules induced by intense X-ray free-electron laser pulses.

We studied the electronic and nuclear dynamics of I-containing organic molecules induced by intense hard X-ray pulses at the XFEL facility SACLA in Japan. The interaction with the intense XFEL pulse causes absorption of multiple X-ray photons by the iodine atom, which results in the creation of many electronic vacancies (positive charges) via the sequential electronic relaxation in the iodine, followed by intramolecular charge redistribution. In a previous study we investigated the subsequent fragmentation by Coulomb explosion of the simplest I-substituted hydrocarbon, iodomethane (CH3I). We carried out three-dimensional momentum correlation measurements of the atomic ions created via Coulomb explosion of the molecule and found that a classical Coulomb explosion model including charge evolution (CCE-CE model), which accounts for the concerted dynamics of nuclear motion and charge creation/charge redistribution, reproduces well the observed momentum correlation maps of fragment ions emitted after XFEL irradiation. Then we extended the study to 5-iodouracil (C4H3IN2O2, 5-IU), which is a more complex molecule of biological relevance, and confirmed that, in both CH3I and 5-IU, the charge build-up takes about 10 fs, while the charge is redistributed among atoms within only a few fs. We also adopted a self-consistent charge density-functional based tight-binding (SCC-DFTB) method to treat the fragmentations of highly charged 5-IU ions created by XFEL pulses. Our SCC-DFTB modeling reproduces well the experimental and CCE-CE results. We have also investigated the influence of the nuclear dynamics on the charge redistribution (charge transfer) using nonadiabatic quantum-mechanical molecular dynamics (NAQMD) simulation. The time scale of the charge transfer from the iodine atomic site to the uracil ring induced by nuclear motion turned out to be only ∼5 fs, indicating that, besides the molecular Auger decay in which molecular orbitals delocalized over the iodine site and the uracil ring are involved, the nuclear dynamics also play a role for ultrafast charge redistribution. The present study illustrates that the CCE-CE model as well as the SCC-DFTB method can be used for reconstructing the positions of atoms in motion, in combination with the momentum correlation measurement of the atomic ions created via XFEL-induced Coulomb explosion of molecules.

Sinistral portal hypertension after pancreaticoduodenectomy with splenic vein ligation.

BACKGROUND: Splenic vein ligation may result in sinistral (left-sided) portal hypertension and gastrointestinal haemorrhage. The aim of this study was to analyse the pathogenesis of sinistral portal hypertension following splenic vein ligation in pancreaticoduodenectomy. METHODS: Patients who underwent pancreaticoduodenectomy for pancreatic cancer between January 2005 and December 2012 were included in this retrospective study. The venous flow pattern from the spleen and splenic hypertrophy were examined after surgery. RESULTS: Of 103 patients who underwent pancreaticoduodenectomy with portal vein resection, 43 had splenic vein ligation. There were two predominant venous flow patterns from the spleen. In the varicose route (27 patients), flow from the spleen passed to colonic varices and/or other varicose veins. In the non-varicose route, flow from the spleen passed through a splenocolonic collateral (14 patients) or a spontaneous splenorenal shunt (2 patients). The varicose route was associated with significantly greater splenic hypertrophy than the non-varicose route (median splenic hypertrophy ratio 1·52 versus 0·94; P < 0·001). All patients with the varicose route had colonic varices, and none had a right colic marginal vein at the hepatic flexure. CONCLUSION: Pancreaticoduodenectomy with splenic vein ligation may lead to sinistral portal hypertension. To avoid the development of varices, it is important to preserve the right colic marginal vein. Reconstruction of the splenic vein should be considered if the right colic marginal vein is divided.

Liver transection using the LigaSure sealing system.

BACKGROUND: The aim of the present study was to evaluate the feasibility and efficacy of the LigaSure vessel sealing system on a large scale when used for liver resection. METHODS: We retrospectively analyzed the short-term outcomes of 277 patients undergoing hepatectomies with the use of the LigaSure system. RESULTS: There were two hospital deaths (0.7%), and the morbidity rate was 25.3%. Mean blood loss during liver transection was 352+/-422 ml, and the liver transection speed was 1.9+/-0.86 cm(2)/min. The number of ties required during liver transection was 13.2+/-13. The morbidity and mortality rate was similar when comparing patients with injured livers (chronic hepatitis or cirrhosis) and those with normal livers, but liver transection speed was faster in those with normal livers when compared with those with injured livers (2.00+/-0.88 vs. 1.57+/-0.63 cm(2)/min, p=0.001). CONCLUSIONS: The LigaSure system can be applied safely in patients undergoing liver resection, regardless of whether cirrhosis is present or not.

Role of host nutrition in symbiont regulation: impact of dietary nitrogen on proliferation of obligate and facultative bacterial endosymbionts of the pea aphid Acyrthosiphon pisum.

The impact of host nutrition on symbiont regulation in the pea aphid Acyrthosiphon pisum was investigated. The population density of the obligate symbiont Buchnera aphidicola positively correlated with dietary nitrogen levels. In contrast, the population density of the facultative symbiont Serratia symbiotica increased in aphids reared on low-nitrogen diets, indicating distinct regulatory mechanisms in the same insect host.

[Intralobar pulmonary sequestration with high level of serum CEA; report of a case].

We reported a case of intralobar pulmonary sequestration with a high level of the serum CEA. A 53-year-old woman whose chief complaint was cough was admitted to our hospital. Enhanced chest computed tomography (CT) revealed the mass in the left lower lung, lymph-nodes swelling, and the aberrant artery. Magnetic resonance angiography (MRA) conformed the aberrant artery from the descending aorta. The level of serum CEA elevated at 9.6 ng/ml. Left lower lobectomy was performed. A diagnosis of intralobar pulmonary sequestration (Pryce type II) was established in this case. Histopathologically, the peribronchial epithelial cells in pulmonary sequestration showed weak positive for anti-CEA monoclonal antibody. Postoperative course was uneventful and the serum CEA level was 3.5 ng/ml in the normal range at the postoperative 17th day.

The wide distribution of endornaviruses, large double-stranded RNA replicons with plasmid-like properties.

The International Committee on Taxonomy of Viruses (ICTV) recently accepted Endornavirus as a new genus of plant dsRNA virus. We have determined the partial nucleotide sequences of the RNA-dependent RNA polymerase regions from the large dsRNAs (about 14 kbp) isolated from barley (Hordeum vulgare), kidney bean (Phaseolus vulgaris), melon (Cucumis melo), bottle gourd (Lagenaria siceraria), Malabar spinach (Basella alba), seagrass (Zostera marina), and the fungus Helicobasidium mompa. Phylogenetic analyses of these seven dsRNAs indicate that these dsRNAs are new members of the genus Endornavirus that are widely distributed over the plant and fungal kingdoms.

[Pulmonary pleomorphic carcinoma].

Pleomorphic carcinoma is a rare primary pulmonary malignancy. We report 2 surgical cases of pulmonary pleomorphic carcinoma. The first case was a 71-year-old male. Chest computed tomography (CT) showed a rapidly growing tumor with irregular density. Transbronchial lung biopsy revealed the tumor to be malignant. Left lower lobectomy was performed. Pathological diagnosis was pleomorphic carcinoma (pT2N2M0, stage IIIA). He died 8 months after surgery due to brain metastasis and mediastinal lymph node metastasis. The second case was a 74-year-old male who complained of bloody sputum. Chest CT showed a tumor with cavity in the right middle lobe. Brushing cytology under bronchofiberscopy revealed atypical cell. Right middle lobectomy and partial resection of the right lower lobe were performed. Pathological diagnosis was also pleomorphic carcinoma (pT2N0M0, stage IB). He has no findings of recurrence nor metastasis 15 months after the operation.

[Mucoepidermoid carcinoma with high level of serous carcinoembryonic antigen; report of a case].

We reported a case of mucoepidermoid carcinoma with a high level of the serum CEA. A 38-year-old woman was admitted because of abnormal chest shadow. Bronchoscopy revealed polypoid tumor occluding the lumen of right B3 bronchus. Bronchoscopic biopsy suggested a diagnosis of tubular adenocarcinoma. Chest computed tomography (CT) confirmed the mass in the right upper lung field and the swelling of right bronchial lymph node. The CEA level of serum elevated at 12.4 ng/ml. A right upper and middle lobectomy with mediastinal lymph nodes dissection was performed on August 26, 2003. Histopathologically, the polypoid tumor was a low grade mucoepidermoid carcinoma with partially extrabronchial extension. However, no lymph nodes metastasis were noted. The cytoplasms of about 45% of tumor cells showed positive for anti-CEA monoclonal antibody. Pathological stage was IB (T2N0M0). Seventeen months has passed with no evidence of recurrence and the CEA level of serum was in the normal range.

Characterization of a facultative endosymbiotic bacterium of the pea aphid Acyrthosiphon pisum.

The pea aphid U-type symbiont (PAUS) was investigated to characterize its microbiological properties. Fluorescence in situ hybridization (FISH) and electron microscopy revealed that PAUS was a rod-shaped bacterium found in three different locations in the body of the pea aphid Acyrthosiphon pisum: sheath cells, secondary mycetocytes, and hemolymph. Artificial transfer experiments revealed that PAUS could establish stable infection and vertical transmission when introduced into uninfected pea aphids. When 28 aphid species collected in Japan were subjected to a diagnostic PCR assay, four species of the subfamily Aphidinae (Aphis citricola, Aphis nerii, Macrosiphum avenae, and Uroleucon giganteus) and a species of the subfamily Pemphiginae (Colopha kansugei) were identified to be PAUS-positive. The sporadic incidences of PAUS infection without reflecting the aphid phylogeny can be best explained by occasional horizontal transfers of the symbiont across aphid lineages.

[Chronic hemorrhagic pyothorax treated with preoperative internal thoracic and intercostal arterial embolization and perioperative non-invasive positive pressure ventilation].

We reported successful surgery for chronic hemorrhagic empyema with severe right heart insufficiency. The preoperative embolization of right internal thoracic artery and intercostals arteries was effective for the control of intraoperative bleeding. Non-invasive positive pressure ventilation (NIPPV) was useful for the perioperative respiratory management. A 62-year-old female with a history of right pneumonectomy and thoracoplasty for pulmonary tuberculosis was admitted because of dyspnea on effort on Dec 5th 2002. Her right heart insufficiency was worsened gradually. On May 20th 2003, we performed the transcatheter embolization of right internal thoracic and intercostals arteries for the control of intraoperative bleeding. The next day, the curettage and fenestration was performed for intraoperative cardiac dysfunction. The intraoperative bleeding was 1,596 ml and operative time was 2 hours 24 minutes. Due to CO2 narcosis, the ventilator under the intratracheal tube was needed for respiratory management in the postoperative course. The switching of the respiratory management with NIPPV from the intratracheal tube during 8 days, her respiratory and general conditions had been improved gradually. Because of methicillin-resistant Staphylococcus aureus (MRSA) infection of thoracic cavity, the radical thoracoplasty following the latissimus dorsi muscules flap and the omentopexy was performed. The operative course was uneventful and she needed overnight NIPPV without O2 inhalation and was discharged.

Aberrant HS1 molecule in a patient with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the activation of autoreactive B lymphocytes, which are supposed to carry aberrant signal transduction after the stimulation of B-cell receptor (BCR). To investigate abnormalities in BCR-mediated signaling pathway in lupus B lymphocytes, we analyzed HS1, a molecule downstream of BCR, in 80 Japanese SLE patients. We identified 37 amino acid deletion of HS1 in a 25-year-old female patient, and the aberrant HS1 lacked a part of a functional motif. Analysis of genomic DNA revealed that the aberrant HS1 was caused by exon skipping. Family study showed that the patient as well as her father and sister are heterozygous for the abnormality. WEHI-231 cell, a mouse B cell line, transfected with the aberrant HS1 displayed a significantly increased cell death upon cross-linking of BCR. Additionally, peripheral B lymphocytes from the patient exerted increased apoptosis after BCR stimulation compared to those from control SLE patients. These data suggest that the aberrant HS1 molecule may transmit an accelerated signal after BCR stimulation and may play a role in the activation of autoreactive B lymphocytes.

Association between blood pressure and insulin resistance in obese females during weight loss and weight rebound phenomenon.

The purpose of this study was to investigate the effect of weight loss on blood pressure and its related variables in moderately obese Japanese females, including an investigation of the rebound phenomenon. Study I examined the effects of weight loss on blood pressure in 138 moderately obese, nondiabetic females (BMI 29.3+/-0.3 kg/M2; age, 46.3+/-0.8 years) during a 3-month therapeutic dietary and exercise program. Study II investigated the effect of weight rebound on blood pressure over an additional 21 months of exercise in 48 subjects from Study I subjects. After 3 months, the BMI significantly decreased to 27.9+/-0.3 kg/m2. Abdominal total fat, visceral fat (V), and subcutaneous fat (S) also decreased significantly. In addition, the summation of insulin (sigmaIRI), plasma glucose (sigmaPG) and HOMA during 75 g oral glucose tolerance test also all significantly decreased. Significant decreases in both the SBP and DBP were observed after the 3 month weight reduction program. Multiple regression analysis revealed that the reduction in SBP was significantly and positively associated with the reduction in log sigmaIRI and the reduction in log 24h-urinary norepinephrine excretion at the end of Study I. The DBP showed a significantly positive association with the log sigmaIRI. With regard to the weight rebound phenomenon, Study II showed that the SBP, DBP and sigmaIRI all increased significantly, and a positive correlation was observed between the changes in the SBP and those in the log sigmaIRI. However, no such correlation was observed regarding the abdominal total fat and visceral fat during both periods. These results suggest that weight loss therefore caused the BP to decrease due to both an improvement in hyperinsulinemia and a decrease in the adrenergic activity which may be involved in the urinary catecholamine. As a result, hyperinsulinemia is thus considered to play an important role in the pathogenesis of blood pressure due to obesity not only during weight loss, but also during the weight rebound phenomenon.

Histamine regulates T-cell and antibody responses by differential expression of H1 and H2 receptors.

Many pathological processes, including those causing allergies and autoimmune diseases, are associated with the presence of specialized subsets of T helper cells (TH1 and TH2) at the site of inflammation. The diversity of TH1 and TH2 function is not predetermined but depends on signals that drive the cells towards either subset. Histamine, released from effector cells (mast cells and basophils) during inflammatory reactions can influence immune response. Here we report that histamine enhances TH1-type responses by triggering the histamine receptor type 1 (H1R), whereas both TH1- and TH2-type responses are negatively regulated by H2R through the activation of different biochemical intracellular signals. In mice, deletion of H1R results in suppression of interferon (IFN)-gamma and dominant secretion of TH2 cytokines (interleukin (IL)-4 and IL-13). Mutant mice lacking H2R showed upregulation of both TH1 and TH2 cytokines. Relevant to T-cell cytokine profiles, mice lacking H1R displayed increased specific antibody response with increased immunoglobulin-epsilon (IgE) and IgG1, IgG2b and IgG3 compared with mice lacking H2R. These findings account for an important regulatory mechanism in the control of inflammatory functions through effector-cell-derived histamine.

Spiroplasma symbiont of the pea aphid, Acyrthosiphon pisum (Insecta: Homoptera).

From a laboratory strain of the pea aphid, Acyrthosiphon pisum, we discovered a previously unknown facultative endosymbiotic bacterium. Molecular phylogenetic analysis based on 16S ribosomal DNA revealed that the bacterium is a member of the genus Spiroplasma. The Spiroplasma organism showed stable vertical transmission through successive generations of the host. Injection of hemolymph from infected insects into uninfected insects established a stable infection in the recipients. The Spiroplasma symbiont exhibited negative effects on growth, reproduction, and longevity of the host, particularly in older adults. Of 58 clonal strains of A. pisum established from natural populations in central Japan, 4 strains possessed the Spiroplasma organism.

RNA-dependent RNA polymerase activity associated with endogenous double-stranded RNA in rice.

RNA-dependent RNA polymerase (RdRp) activity was detected in the crude microsomal fraction of rice cultured cells that contain a 14 kbp double-stranded RNA (dsRNA). RdRp activity is maximal in the presence of all four nucleotide triphosphates and Mg2+ ion and is resistant to inhibitors of DNA-dependent RNA polymerases (actinomycin D and alpha-amanitin). RdRp activity increases approximately 2.5-fold in the presence of 0.5% deoxycholate. Treatment of purified microsomal fraction with proteinase K plus deoxycholate suggests that the RdRp enzyme complex with its own 14 kb RNA template is located in vesicles. The RdRp enzyme complex was solubilized with Nonidet P-40 and purified by glycerol gradient centrifugation, then exogenous RNA templates were added. Results indicate that exogenous dsRNA reduces RNA synthesis from the endogenous 14 kb RNA template.

Stable inversion method for a polarized-lidar: analysis and simulation.

A new inversion inhomogeneous atmosphere (IA) method that is more stable than Fernald's method for two-component (molecule and aerosol) scattering analysis of polarized Mie lidar signals is proposed and examined. The backscattering coefficient and the extinction-to-backscattering ratio (EBR) can be calculated for specified regions at which the depolarization ratio is less than that of molecule without further assumptions. The inversion procedure can be extended to both inward stepwise and outward stepwise integration algorithms. Simulation results indicate that a higher precision was achieved with the IA method than with Fernald's method in terms of error and random noise in estimating boundary value and EBR. Experimental results were also better with the IA method than with Fernald's method.

The secondary endosymbiotic bacterium of the pea aphid Acyrthosiphon pisum (Insecta: homoptera).

The secondary intracellular symbiotic bacterium (S-symbiont) of the pea aphid Acyrthosiphon pisum was investigated to determine its prevalence among strains, its phylogenetic position, its localization in the host insect, its ultrastructure, and the cytology of the endosymbiotic system. A total of 14 aphid strains were examined, and the S-symbiont was detected in 4 Japanese strains by diagnostic PCR. Two types of eubacterial 16S ribosomal DNA sequences were identified in disymbiotic strains; one of these types was obtained from the primary symbiont Buchnera sp., and the other was obtained from the S-symbiont. In situ hybridization and electron microscopy revealed that the S-symbiont was localized not only in the sheath cells but also in a novel type of cells, the secondary mycetocytes (S-mycetocytes), which have not been found previously in A. pisum. The size and shape of the S-symbiont cells were different when we compared the symbionts in the sheath cells and the symbionts in the S-mycetocytes, indicating that the S-symbiont is pleomorphic under different endosymbiotic conditions. Light microscopy, electron microscopy, and diagnostic PCR revealed unequivocally that the hemocoel is also a normal location for the S-symbiont. Occasional disordered localization of S-symbionts was also observed in adult aphids, suggesting that there has been imperfect host-symbiont coadaptation over the short history of coevolution of these organisms.

Abnormal functional and morphological regulation of the gastric mucosa in histamine H2 receptor-deficient mice.

To clarify the physiological roles of histamine H2 receptor (H2R), we have generated histamine H2R-deficient mice by gene targeting. Homozygous mutant mice were viable and fertile without apparent abnormalities and, unexpectedly, showed normal basal gastric pH. However, the H2R-deficient mice exhibited a marked hypertrophy with enlarged folds in gastric mucosa and an elevated serum gastrin level. Immunohistochemical analysis revealed increased numbers of parietal and enterochromaffin-like (ECL) cells. Despite this hypertrophy, parietal cells in mutant mice were significantly smaller than in wild-type mice and contained enlarged secretory canaliculi with a lower density of microvilli and few typical tubulovesicles in the narrow cytoplasm. Induction of gastric acid secretion by histamine or gastrin was completely abolished in the mutant mice, but carbachol still induced acid secretion. The present study clearly demonstrates that H2R-mediated signal(s) are required for cellular homeostasis of the gastric mucosa and normally formed secretory membranes in parietal cells. Moreover, impaired acid secretion due to the absence of H2R could be overcome by the signals from cholinergic receptors.

Phylogenetic analysis of some large double-stranded RNA replicons from plants suggests they evolved from a defective single-stranded RNA virus.

Sequences were recently obtained from four double-stranded (ds) RNAs from different plant species. These dsRNAs are not associated with particles and as they appeared not to be horizontally transmitted, they were thought to be a kind of RNA plasmid. Here we report that the RNA-dependent RNA polymerase (RdRp) and helicase domains encoded by these dsRNAs are related to those of viruses of the alpha-like virus supergroup. Recent work on the RdRp sequences of alpha-like viruses raised doubts about their relatedness, but our analyses confirm that almost all the viruses previously assigned to the supergroup are related. Alpha-like viruses have single-stranded (ss) RNA genomes and produce particles, and they are much more diverse than the dsRNAs. This difference in diversity suggests the ssRNA alpha-like virus form is older, and we speculate that the transformation to a dsRNA form began when an ancestral ssRNA virus lost its virion protein gene. The phylogeny of the dsRNAs indicates this transformation was not recent and features of the dsRNA genome structure and translation strategy suggest it is now irreversible. Our analyses also show some dsRNAs from distantly related plants are closely related, indicating they have not strictly co-speciated with their hosts. In view of the affinities of the dsRNAs, we believe they should be classified as viruses and we suggest they be recognized as members of a new virus genus (Endornavirus) and family (Endoviridae).